WO2023209082A1

WO2023209082A1 - Combinations of an organic polymer and calcium silicate hydrate for producing mineral water-proofing membranes

Info

Publication number: WO2023209082A1
Application number: PCT/EP2023/061098
Authority: WO
Inventors: Christian Schmidtke; Ekkehard Jahns; Klaus Seip; Christoph Hesse; Michael DIETZSCH; Viktoria Kraus; Astrid Weber
Original assignee: Basf Se
Priority date: 2022-04-29
Filing date: 2023-04-27
Publication date: 2023-11-02

Abstract

The present invention relates to the use of combinations of an organic polymer P and calcium silicate hydrate CSH for producing mineral water-proofing membranes which comprise at least one mineral binder, in particular a cementitious binder. The present invention also relates to compositions for producing mineral water-proofing membranes containing and methods for producing mineral water-proofing membranes The combination comprises: a) an organic polymer P as a component A in the form of an aqueous polymer dispersion or in the form of a polymer powder, where the organic polymer P is a vinylacetate-ethylene copolymer, where the organic polymer P has a glass transition temperature Tg of at most +10°C, in particular in the range of -30 to +5°C, especially in the range of -20 to +0°C, as determined by the differential scanning calorimetry (DSC) method according to ISO 11357-2:2013, and b) a component B comprising particles of a calcium silicate hydrate containing calcium and silicon in a molar ratio Ca/Si in the range of 0.1 to 2.2, in particular in the range of 0.5 to 2.2 and especially in the range of 1.5 to 2.2. A second aspect of the invention relates to compositions for producing mineral water-proofing membranes which comprises a combination of the components A and B as defined herein and a powdery composition C comprising c.1 at least one mineral binder, in particular a mineral binder comprising a cement of the cement group CEM I according to EN 197, more particularly a cement classified as CEM I 42.5(R) or CEM I 52.5(R) or a mixture thereof; and c.2 at least one powdery filler. A third aspect of the invention relates to a method for producing mineral waterproofing membranes which comprises incorporating a combination of the components A and B as defined herein and water into a powdery composition C comprising a mineral binder c.1 as defined herein and at least one powdery filler c.2 as described herein to obtain a slurry and applying the slurry to a surface, where a mineral waterproofing membrane is required.

Description

Combinations of an organic polymer and calcium silicate hydrate for producing mineral water-proofing membranes

The present invention relates to the use of combinations of an organic polymer P and calcium silicate hydrate CSH for producing mineral water-proofing membranes which comprise at least one mineral binder, in particular a cementitious binder. The present invention also relates to compositions for producing mineral water-proofing membranes containing and methods for producing mineral water-proofing membranes

TECHNICAL BACKGROUND

In construction, mineral water-proofing membranes are used for example in water drains, such as sewage or rainwater drains and lines, or as water barrier under tiles in wet rooms (e.g. bathrooms), swimming pools or water tanks. They are typically based on a mineral binder, in particular a hydraulically setting mineral binder, and an organic polymer as a co-binder. The polymeric co-binder improves the mechanical properties of the the mineral water-proofing membranes, such as their flexural tensile strength, substrate adhesion, flexibility and crack resistance. For this, the mineral components of the mineral water-proofing membranes, including the mineral binder and optionally fillers, are admixed with one or more polymers in the form of aqueous polydispersions or of the polymer powders obtainable from these dispersions. A disadvantage of these polymers is that they generally exhibit a retardant effect on the setting behavior of the water-proofing slurries for producing the mineral waterproofing membranes.

Besides good mechanical properties, fast drying and rapid setting and a high "early strength" are important properties of the slurries for producing mineral waterproofing membranes, in particular those based on cementitious binders (hereinafter cementitious waterproofing membranes). Moreover, the water-uptake of the mineral waterproofing membranes should be low when being in contact with water for prolonged time, because a high water-uptake leads to a water-swollen covering, which may result in leakage, decreased mechanical strength and crack formation.

It is known as that the setting of mortars and concrete can be achieved by conventional accelerators, such as calcium formate, calcium chloride or lithium carbonate. These ac- celarators are included into the components of the mortar or concrete compositions. A problematic property of conventional accelerators is that they result in poor corrosion resistance or suffer from the development of efflorescence. A further disadvantage is the relatively large amount in which the known accelerators are used. In order to obtain an even more rapid setting behavior and even higher early strengths in conjunction with constant ultimate strengths for concrete or mortar compositions finely divided calcium silicate hydrates (CSH) in the form of powders or aqueous dispersions are presently in use. Such finely divided calcium silicate hydrates, and their preparation, are described, for example, in WO 2010/026155, WO 2011/026720, WO 2011/026723, WO 2012/143205, WO 2014/114784 and WO 2018/154012.

A disadvantage of calcium silicate hydrates is that their accelerating effect on the setting of the mortars and concretes as adversely affected by polymers, in particular if the polymers are present in large amounts as in compositions for waterproofing membranes. Moreover, calcium silicate hydrate may be incompatible with aqueous polymer dispersions and thus cause instability of the aqueous polymer dispersions.

WO 2013/117465 describes aqueous dispersions containing a finely divided calcium silicate hydrate and polymer P in the form of an aqueous polymer dispersion, where the polymer P is an all-acrylate polymer or a styrene acrylate polymer containing small amounts of a hydroxyalkyl(meth)acrylate or a (meth) acrylamide. While the dispersions show good stability and provide acceptable tensile adhesion, the setting behavior is adversely affected. Moreover, the presence of CSH may result in an increased water-up- take.

US 2012/0077906 describes a compositions for providing water-tight roof coatings which contain one or more polymers, in particular vinylacetate-ethylene copolmers, a cement and one or more fillers and which have a polymer cement ratio of at least 1.8:1. The compositions have a comparativlely high water-uptake.

SUMMARY OF THE INVENTION

It is the object of the present invention to provide compositions for mineral water-tight applications, in particular for producing mineral waterproofing membranes, which besides good mechanical properties and good bond strength, are fast drying and rapid setting and provide a high "early strength". Moreover, a low water-uptake of the covering after setting is highly desiable.

The object is achieved by incorporating a combination of the components A and B as defined herein, a) an organic polymer P as a component A in the form of an aqueous polymer dispersion or in the form of a polymer powder, where the organic polymer P is a vi- nylacetate-ethylene copolymer, where the organic polymer P has a glass transition temperature Tg of at most +10°C, in particular in the range of -30 to +5°C, especially in the range of -20 to +0°C, as determined by the differential scanning calorimetry (DSC) method according to ISO 11357-2:2013, and b) a component B comprising particles of a calcium silicate hydrate containing calcium and silicon in a molar ratio Ca/Si in the range of 0.1 to 2.2, in particular in the range of 0.5 to 2.2 and especially in the range of 1 .5 to 2.2; in compositions for producing mineral waterproofing membranes, i.e. in waterproofing membranes which comprise at least one mineral binder.

Therefore, a first aspect of the invention thus relates to the use of the combination of components A and B in in compositions for producing waterproofing membranes, which comprise at least one mineral binder.

A second aspect of the invention relates to compositions for producing mineral waterproofing membranes which comprises a combination of the components A and B as defined herein and a powdery composition C comprising c.1 at least one mineral binder, in particular a mineral binder comprising a cement of the cement group CEM I according to EN 197, more particularly a cement classified as CEM I 42.5(R) or CEM I 52.5(R) or a mixture thereof; and c.2 at least one powdery filler.

A third aspect of the invention relates to a method for producing mineral waterproofing membranes which comprises incorporating a combination of the components A and B as defined herein and water into a powdery composition C comprising a mineral binder c.1 as defined herein and at least one powdery filler c.2 as described herein to obtain a slurry and applying the slurry to a surface, where a mineral waterproofing membrane is required.

A fourth aspect of the invention relates to powdery composition consisting of a) an organic polymer P as a component A in the form of an aqueous polymer dispersion or in the form of a polymer powder, where the organic polymer P is a vi- nylacetate-ethylene copolymer, where the organic polymer has a glass transition temperature Tg of at most +10°C, in particular in the range of -30 to +5°C, especially in the range of -20 to +0°C, as determined by the differential scanning calorimetry (DSC) method according to ISO 11357-2:2013, b) a component B comprising particles of a calcium silicate hydrate containing calcium and silicon in a molar ratio Ca/Si in the range of 0.1 to 2.2, in particular in the range of 0.5 to 2.2 and especially in the range of 1 .5 to 2.2; and d) up to 30% by weight of further ingredients, based on the total weight of the composition; wherein the weight ratio of the organic polymer of component A to the total amount of CSH in component B is in the range of 800:1 to 10:1 , preferably in the range of 200:1 to 10:1 , in particular in the range of 150:1 to 20:1 and especially in the range of 100:1 to 30:1.

The invention is associated with several benefits. The combination of the components A and B can be easily incorporated into compositions for producing mineral waterproofing membranes. The combination of the components A and B provide for mineral waterproofing membranes, which besides good mechanical properties, such as high flexural tensile strength, flexibility and crack resistance, and good bond strength or substrate adhesion, are fast drying and rapid setting and provide a high "early strength". Moreover, they provide a low water-uptake of the covering after setting of the composition which forms the mineral waterproofing membrane.

DETAILED DESCRIPTION OF THE INVENTION

Here and in the following, the definitions of the components A, B, C and D and the preferences regarding the embodiments of components A, B, C and D and also the relative amounts of the components apply to all aspects of the invention in the same way.

Here and in the following mineral binders are understood as meaning inorganic compounds which, after being brought into contact with water, solidify in a stone-like manner over time when left to themselves in the air under atmospheric conditions or partly also under water. Such mineral binders are also termed hydraulic binders. Hydraulic binders include but are not limited to calcined lime, gypsum, blastfurnace slag, fly ash, silica fume, metakaolin, natural pozzolans or burnt oil shale, cements (see for example EN 197-1) such as Portland cements, white cements, thurament, celite, alumina cements, swelling cements, blastfurnace cements and combinations thereof.

If not stated otherwise, the terms “powder” and “powdery compositions” refer to free flowing compositions of particles wherein at least 90% by weight of the particles have a particle size of at most 500 pm, in particular of at most 400 pm, especially of at most 300 pm. The particle size given here refers to the D90 value. Particle sizes, such as D10, D50 and D90 values and particle size distributions of powders and powdery materials can be determined using a wide variety of measurement methods known per se to the person skilled in the art, for example via sieve analyses according to DIN 66165- 2:2016-08, sedimentation or light scattering, e.g. laser diffraction in accordance with DIN ISO 13321 :2004-10. In the present case, given particle sizes of the components of the powdery compositions C are either such as indicated by the commercial producer or as determined using sieve analyses according to DIN 66165-2:2016-08.

Here and in the following the content of calcium silicate hydrate in the component B and in the powder composition (C-S-H content) can be calculated by determining the solids content of the respective powder or suspensions through evaporation of the volatile water part followed by substraction of the amount of organic part (e.g. dispersing agents, spray-drying aids etc.), followed by substraction of the mass of ions besides the calcium and silicate ions that were introduced during synthesis.

The prefix C_n-C_m refers to the number of carbon atoms a molecule or radical may have. For example, C_n-C_m-alkyl refers to the group of linear or branched alkyl radicals having from n to m carbon atoms.

The term C1-C4 alkyl refers to linear or branched alkyl radicals which have 1 , 2, 3 or 4 carbon atoms, examples thereof being methyl, ethyl, n-propyl, 2-propyl, 1 -butyl, 2-butyl, 2-methyl-1 -propyl (isobutyl) and 2-methyl-2-propyl (tert.-butyl).

Here and in a following, an organic polymer is termed water soluble if the organic polymer at 20 C and atmospheric pressure has a solubility in water of at least 10 gram per liter (g/L), in particular at least 20g/L and especially at least 50 g/L.

As a component A, the combination and compositions of the method comprise a vinyl acetate-ethylene copolymer in the form of a powder or an aqueous polymer dispersion.

The term “vinyl acetate-ethylene copolymer” is well understood as a copolymer of vinyl acetate and ethylene and optionally one or more further comonomers, wherein the polymerized units of vinyl acetate and ethylene form the majority, i.e. at least 50% by weight or at least 55% by weight or at least 60% by weight, of all repeating units in the vinyl acetate-ethylene copolymer. The total amount of repeating units stemming from vinylacetate and ethylene may be as high as 100% by weight, based on the total weight of the monomers forming the vinyl acetate-ethylene copolymer.

In particular, the monomers forming the vinyl acetate-ethylene copolymer comprise 30 to 95% by weight of vinyl acetate and 5 to 70 wt % of ethylene, preferably 40 to 90% by weight of vinyl acetate and 10 to 60 wt % of ethylene, especially 50 to 90% by weight of vinyl acetate and 10 to 50 wt % of ethylene, based in each case on the total weight of the monomers forming the vinyl acetate-ethylene copolymer. The monomers forming the vinyl acetate-ethylene copolymer may optionally comprise one or more further comonomers in an amount of up to 50% by weight, preferably up to 45% by weight and especially up to 40% by weight.

Suitable further comonomers are those monoethylenically unsaturated neutral monomers having a solubility in deionized water at 25°C and 1 bar of at most 40 g/L. Example of such monomers are

- vinyl esters having 3 to 12 carbon atoms in the carboxylic acid radical, such as vinyl propionate, vinyl laurate, vinyl esters of alpha-branched carboxylic acids having 8 to 11 carbon atoms such as VeoVaOEH, VeoVa®9 or VeoVa®10 (tradenames of Resolution); methacrylic esters or acrylic esters of unbranched or branched alcohols having

1 to 15 carbon atoms, such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate, norbornyl acrylate.

- vinyl halides such as vinyl chloride.

The relative amount of such further neutral monomers, if present, is typically in the range of 1 to 50% by weight, in particular 5 to 45% by weight or 5 to 40% by weight, based on the total amount of monomers forming the vinyl acetate-ethylene copolymer.

Suitable further comonomers inlcude auxiliary monomers. Suitable auxiliary monomers include monoethylenically unsaturated monocarboxylic and dicarboxylic acids, preferably acrylic acid, methacrylic acid, fumaric acid, and maleic acid; ethylenically unsaturated carboxamides and carbonitriles, preferably acrylamide and acrylonitrile; monoesters and diesters of fumaric acid and maleic acid such as the diethyl and diisopropyl esters, and also maleic anhydride, ethylenically unsaturated sulfonic acids and/or their salts, preferably vinyl- sulfonic acid, 2-acrylamido-2-methyl-propanesulfonic acid. precrosslinking comonomers such as polyethylenically unsaturated comonomers, as for example divinyl adipate, diallyl maleate, allyl methacrylate or triallyl cyan urate, postcrosslinking comonomers, as for example acrylamidoglycolic acid (AGA), methylacrylamidoglycolic acid methyl ester (MAGME), N-methylolacrylamide (NMA), N-methylolmethacrylamide (NMMA), N-methylolallylcarbamate, alkyl ethers such as the isobutoxy ether or esters of N-methylolacrylamide or of N- methylolmethacrylamide and of N-methylolallylcarbamate. - Also suitable are monomers with hydroxyl groups, such as, for example, methacrylic hydroxyalkyl esters and acrylic hydroxyalkyl esters such as hydroxyethyl, hydroxypropyl or hydroxybutyl acrylate or methacrylate, and also

1 ,3-dicarbonyl compounds such as acetoacetoxyethyl acrylate, acetoacetoxypropyl methacrylate, acetoacetoxyethyl methacrylate, ancetoacetoxybutyl methacrylate, 2,3-di(acetoacetoxy)propyl methacrylate, and allyl acetoacetate; monoethylenically unsaturated comonomers with epoxide functionality such as glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, vinyl glycidyl ether. Further examples of suitable further comonomers are comonomers with silicon functionality, such as acryloyloxypropyltri(alkoxy)- and methacryloyloxypro- pyltri(alkoxy)-silanes, vinyltrialkoxysilanes and vinylmethyldialkoxysilanes, preferably with alkyl and/or alkoxy groups having in each case 1 to 2 carbon atoms, as for example vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloyloxy- propyltrimethoxysilane.

The relative amount of such auxiliary monomers, if present, is typically in the range of 0.1 to 20% by weight, in particular 0.2 to 10% by weight or 0.5 to 5% by weight, based on the total amount of monomers forming the vinyl acetate-ethylene copolymer.

Particularly preferred polymers P are copolymers of 40 to 95% by weight of vinyl acetate with 5 to 60% by weight of ethylene, in particular copolymers of 50 to 90% by weight of vinyl acetate with 10 to 50% by weight of ethylene; copolymers of 40 to 90% by weight of vinyl acetate with 5 to 50% by weight of ethylene and 5% to 50% by weight of one or more further comonomers from the group consisting of vinyl esters having 1 to 12 C atoms in the carboxylic acid radical such as vinyl propionate, vinyl laurate, vinyl esters of alpha-branched carboxylic acids having 9 to 13 C atoms such as VeoVa9, VeoVal O, VeoVal 1 ; copolymers of 40 to 90% by weight of vinyl acetate with 5 to 45% by weight of ethylene and 5% to 45% by weight of (meth)acrylic esters of unbranched or branched alcohols having 1 to 15 C atoms, more particularly n-butyl acrylate or 2-ethylhexyl acrylate; and copolymers with 40% to 90% by weight of vinyl acetate, 5 to 40% by weight of ethylene, 1 to 30% by weight of vinyl laurate or vinyl esters of an alphabranched carboxylic acid having 9 to 11 C atoms, and also 1 to 30% by weight of (meth)acrylic esters of unbranched or branched alcohols having 1 to 15 C atoms, more particularly n-butyl acrylate or 2-ethylhexyl acrylate; copolymers of 40 to 90% by weight of vinyl acetate with 5 to 55% by weight of ethylene and 5% to 45% by weight of by weight of vinyl chloride; where the aforementioned copolymers may further contain the aforementioned auxiliary monomers in the aforementioned amounts, and the amounts in % by weight add up in each case to 100% by weight

The type and relative amounts of the monomers forming the vinyl acetate-ethylene copolymer are generally chosen in a way that the vinyl acetate-ethylene copolymer has a glass transition temperature Tg of at most +10°C, of at most +5°C and especially of at most 0°C, e.g. in the range of -40 to +10°C, in particular in the range of -30 to +5°C, especially in the range of -20 to +0°C. The glass transition temperature Tg of the polymers can be determined in a known way of DSC (Differential Scanning Calorimetry, DIN EN ISO 11357-1/2, preferably with sample preparation according to ISO 16805:2003). The glass transition temperature Tg can also be calculated from the monomer composition forming the vinyl acetate-ethylene copolymer. This calculated temperature is also referred to as theoretical glass transition temperatures Tg* which is usually calculated from the monomer composition by the Fox equation:

1 /Tg* = x_a/Tg_a + x /Tg + .... x_n/Tg_n,

In this equation, x_a, x_b x_n are the mass fractions of the monomers a, b n, and Tg_a, Tg_b Tg_n are the actual glass transition temperatures in Kelvin of the homopolymers synthesized from only one of the monomers a, b n at a time. The Fox equation is described by T. G. Fox in Bull. Am. Phys. Soc. 1956, 1 , page 123 and as well as in Ullmann's Encyclopadie der technischen Chemie [Ullmann's Encyclopedia of Industrial Chemistry], vol. 19, p. 18, 4th ed., Verlag Chemie, Weinheim, 1980. The actual Tg values for the homopolymers of most monomers are known and listed, for example, in Ullmann’s Encyclopadie der technischen Chemie [Ullmann's Encyclopedia of Industrial Chemistry], 5th ed., vol. A21 , p. 169, Verlag Chemie, Weinheim, 1992. Further sources of glass transition temperatures of homopolymers are, for example, J. Brandrup, E. H. Immergut, Polymer Handbook, 1st Ed., J. Wiley, New York 1966, 2nd Ed. J. Wiley, New York 1975, 3rd Ed. J. Wiley, New York 1989 and 4th Ed. J. Wiley, New York 2004.

The vinyl acetate-ethylene copolymers are commercially available or they can be prepared in a known way, preferably by radically initiated emulsion polymerization in water. This technique has been exhaustively described in the art, and is therefore well known to the skilled person [cf., e.g., Encyclopedia of Polymer Science and Engineering, vol. 8, pages 659 to 677, John Wiley & Sons, Inc., 1987; D. C. Blackley, Emulsion Polymerisation, pages 155 to 465, Applied Science Publishers, Ltd., Essex, 1975;

D. C. Blackley, Polymer Latices, 2nd edition, vol. 1 , pages 33 to 415, Chapman & Hall, 1997; H. Warson, The Applications of Synthetic Resin Emulsions, pages 49 to 244, Ernest Benn, Ltd., London, 1972; J. Piirma, Emulsion Polymerisation, pages 1 to 287, Academic Press, 1982; F. Holscher, Dispersionen synthetischer Hochpolymerer, pages 1 to 160, Springer-Verlag, Berlin, 1969, and patent specification DE-A 4003422 and US 2012/0077906. The radically initiated aqueous emulsion polymerization is normally accomplished by dispersing the ethylenically unsaturated monomers in aqueous medium, generally with accompanying use of dispersing assistants, such as emulsifiers and/or protective colloids, and polymerizing them by means of at least one water-soluble radical polymerization initiator. In the aqueous polymer dispersions obtained, the residual amounts of unreacted ethylenically unsaturated monomers are frequently lowered by chemical and/or physical techniques that are likewise known to the skilled person [see, for example, EP-A 771328, DE-A 19624299, DE-A 19621027, DE-A 19741184, DE-A 19741187, DE-A 19805122, DE-A 19828183, DE-A 19839199, DE-A 19840586, and 19847115]; the polymer solids content is adjusted to a desired level by dilution or concentration; or the aqueous polymer dispersion is admixed with further customary adjuvants, such as bactericidal, foam-modifying or viscosity-modifying additives, for example.

The monomers forming the vinyl acetate-ethylene copolymer are usually polymerized in the presence of protective colloid or in the presence of emulsifier, or in the presence of a combination of protective colloid and emulsifier.

Customary protective colloids for stabilizing the polymerization batch include, for example, partially or fully hydrolyzed polyvinyl alcohols; polyvinylpyrrolidones; polyvinyl acetals; polysaccharides in water-soluble form such as starches, celluloses or their derivatives, such as carboxymethyl, methyl, hydroxyethyl or hydroxypropyl derivatives; proteins such as casein or caseinate, soy protein, gelatin; lignosulfonates; synthetic polymers such as poly(meth)acrylic acid, copolymers of (meth)acrylates with carboxyl-functional comonomer units, poly(meth)acrylamide, polyvinylsulfonic acids and their water- soluble copolymers; melamine-formaldehyde sulfonates, naphthalene-formaldehyde sulfonates, styrene-maleic acid and vinyl ether-maleic acid copolymers.

Preference is given to celluloses or derivatives thereof, or partially hydrolyzed polyvinyl alcohols having an 80 to 95 mol % degree of hydrolysis and a Hoeppler viscosity in 4% aqueous solution of 1 to 40 mPas, especially 3 to 30 mPas (Hoeppler method at 20° C., DIN 53015). Particular preference is given to partially hydrolyzed polyvinyl alcohols each having a preferably 80 to 95 mol %, more preferably 85 to 90 mol % and most preferably 87 to 89 mol % degree of hydrolysis and which have a low molecular weight and a Hoeppler viscosity of in each case preferably 1 to 5 mPas and more preferably 2 to 4 mPas as determined to DIN 53015, Hoeppler method, at 20° C, in 4% aqueous solution.

It is also possible to use partially hydrolyzed high molecular weight polyvinyl alcohols having a hydrolysis degree of preferably 80 to 95 mol % and a Hoeppler viscosity, in 4% aqueous solution, of preferably >5 to 40 mPas, more preferably 8 to 40 mPas (DIN 53015 Hoeppler method at 20° C) in admixture with the partially hydrolyzed low molecular weight polyvinyl alcohols. It is also possible to use fully hydrolyzed high molecular weight polyvinyl alcohols having a hydrolysis degree of preferably 96 to 100 mol %, especially 98 to 100 mol %, and a Hoeppler visocosity, in 4% aqueous solution, of preferably 10 to 56 mPas (DIN 53015 Hoeppler method at 20° C) in admixture with the partially hydrolyzed low molecular weight polyvinyl alcohols. The partially hydrolyzed high molecular weight polyvinyl alcohols and/or the fully hydrolyzed high molecular weight polyvinyl alcohols are each employed here in an amount of 0.1 to 4 wt %, all based on the total weight of the comonomers.

Preference is also given to modified polyvinyl alcohols, hereinafter also referred to as X-PVOH, having a hydrolysis degree of 80 to 99.9 mol %, preferably 85 to 95 mol %, and a Hoeppler viscosity, in 4% by weight aqueous solution, of 1 to 30 mPas as determined to DIN 53015 at 20° C. Examples thereof are polyvinyl alcohols bearing functional groups, such as acetoacetyl groups. Preference is also given to the so-called E- PVOH polyvinyl alcohols, which contain ethylene units and are known, for example, by the trade name of EXCEVAL®. E-PVOHs are partially or preferably fully hydrolyzed copolymers of vinyl acetate and ethylene. Preferred E-PVOHs have an ethylene content of 0.1 to 12 mol %, preferably 1 to 7 mol %, more preferably 2 to 6 mol % and especially 2 to 4 mol %. The mass-average degree of polymerization is in the range from 500 to 5000, preferably in the range from 2000 to 4500 and more preferably in the range from 3000 to 4000. The hydrolysis degree is generally greater than 92 mol %, preferably in the range from 94.5 to 99.9 mol % and more preferably in the range from 98.1 to 99.5 mol %.

The protective colloids are commercially available and are obtainable using methods known to a person skilled in the art. It is also possible to use mixtures of said protective colloids. The polymerization is preferably carried out in the presence of altogether 2 to 10% by weight of protective colloid, more preferably altogether 5 to 10% by weight, all based on the total weight of the comonomers.

Instead or in combination with the protective colloids the polymerization can be carried out in the presence of emulsifiers, which are in particular non-ionic emulsifiers. Ionic, preferably anionic, emulsifiers can also be used. Combinations of nonionic emulsifiers with anionic emulsifiers are also usable. The emulsifier quantity is generally in the range from 0.1 to 5.0% by weight, based on the total weight of the comonomers.

Suitable nonionic emulsifiers include, for example, acyl, alkyl, oleyl and alkylaryl ethoxylates. These products are commercially available as Genapol® or Lutensol® for example. They subsume ethoxylated mono-, di- and trialkylphenols, preferably with an ethoxylation degree of 3 to 50 ethylene oxide units and C4-C12 alkyl moieties; and also ethoxylated fatty alcohols, preferably with an ethoxylation degree of 3 to 80 ethylene oxide units and C8-C20 alkyl moieties. Suitable nonionic emulsifiers further include C13 to C15 oxo alcohol ethoxylates having an ethoxylation degree of 3 to 30 ethylene oxide units, C16-C18 fatty alcohol ethoxylates with an ethoxylation degree of 11 to 80 ethylene oxide units, C10 oxo process alcohol ethoxylates with an ethoxylation degree of 3 to 11 ethylene oxide units, C13 oxo process alcohol ethoxylates with an ethoxylation degree of 3 to 20 ethylene oxide units, polyoxyethylene sorbitan monooleate with 20 ethylene oxide groups, copolymers of ethylene oxide and propylene oxide with a minimum ethylene oxide content of 10 wt %, polyethylene oxide ethers of oleyl alcohol with an ethoxylation degree of 4 to 20 ethylene oxide units, and also the polyethylene oxide ethers of nonylphenol with an ethoxylation degree of 4 to 20 ethylene oxide units. Particular preference is green to C12-C14 fatty alcohol ethoxylates with an ethoxylation degree of 3 to 30 ethylene oxide units.

Examples of suitable anionic emulsifiers include the sodium, potassium and ammonium salts of linear aliphatic carboxylic acids having 12 to 20 carbon atoms; sodium hydroxyoctadecanesulfonate; the sodium, potassium and ammonium salts of hydroxyl fatty acids having 12 to 20 carbon atoms and their sulfonation and/or acetylation products; the sodium, potassium and ammonium salts of alkyl sulfates, including as triethanolamine salts, and one sodium, potassium and ammonium salts of alkylsulfonates having 10 to 20 carbon atoms each and of alkylarylsulfonates having 12 to 20 carbon atoms; dimethyldialkylammonium chloride having 8 to 18 carbon atoms in the alkyl moiety and sulfonation products thereof; the sodium, potassium and ammonium salts of sulfosuccinic esters with aliphatic saturated monohydric alcohols having 4 to 16 carbon atoms and of sulfosuccinic 4-ester with polyethylene glycol ethers of monohybric aliphatic alcohols having 10 to 12 carbon atoms, especially their disodium salts; the sodium, potassium and ammonium salts of sulfosuccinic 4-ester with polyethylene glycol nonylphenyl ether, especially its disodium salt; the sodium, potassium and ammonium salts of biscyclohexyl sulfosuccinate, especially its sodium salt; lignosulfonic acid and also its calcium, magnesium, sodium and ammonium salts; resin acids and also hydrogenated and dehydrogenated resin acids and also their alkali metal salts. The polymerization temperature is usually in the range of 40°C to 120°C, preferably in the range of 60°C to 90°C. Preference is given to working under pressure, in general in the range of 5 to 120 bar. The polymerization may be initiated using the initiators customary for emulsion polymerization, such as hydroperoxide or tert-butyl hydroperoxide, or using redox initiator combinations, with reducing agents, such as (iso)ascorbic acid or Na hydroxymethanesulfinate (Bruggolite FF). Substances with a regulating action can be used during the polymerization in order to control the molecular weight.

The polymerization is generally in each case carried out to a conversion of >95 wt %, preferably up to a conversion of from 95 to 99 wt %, for the monomers which are liquid under polymerization conditions.

The thus obtainable aqueous dispersions of the vinyl acetate-ethylene copolymer each have a solids content of 30 to 75 wt %, preferably of 50 to 65 wt %. Suitable aqueous dispersions of vinyl acetate-ethylene copolymers are also commercially available; Vinnapas* dispersions from Wacker Chemie AG for example.

The polymers of composition B are insoluble in water and are present in the form of disperse polymer particles within the aqueous coating compositions.

The average diameter of the polymers (polymer particles) present in the aqueous dispersion vinyl acetate-ethylene copolymer is generally in the range from 50 to 1500 nm, frequently in the range from 70 to 1200 nm, e.g. from 100 to 1200 nm. By average particle diameter this specification means the Z average particle diameter as determined by dynamic light scattering (also termed quasielastic light scattering) of an aqueous polymer dispersion diluted with deionized water to 0.001 to 0.5% by weight at 22°C by means of a HPPS from Malvern Instruments, England. What is reported is the cumulant Z average diameter calculated from the measured autocorrelation function (ISO Standard 13321).

The combination further contains a component B which comprises a calcium silicate hydrate in the form of particles, hereinafter abbreviated CSH or C-S-H, respectively. Principally any compositions containing CSH commonly used as accelerator for hydraulically setting binders are suitable. Suitable compositions comprising particles of CSH which can be used as component B are described, for example, in WO 02/070425, WO 2010/026155, WO 2011/026720, WO 2011/026723, WO 2012/025567, WO 2012/143205, WO 2014/114784, WO 2018/154012 and WO 2021/185718. According to the invention, the C-S-H contained in the component B comprises calcium and silicon in a molar ratio Ca/Si in the range of 0.1 to 2.2, in particular in the range of 0.5 to 2.2 and especially in the range of 1 .5 to 2.2. The component B is typically a powder or a suspension of particles comprising the C-S-H.

The calcium-silicate-hydrate may contain elements other than Ca and Si, e. g. elements from the group of transition metals, aluminum, alkali metals and alkaline earth metals, such as magnesium. A skilled person will immediately understand that the elements are present in their oxidic form.

The calcium-silicate-hydrate can be preferably described with regard to its elemental composition by the following empirical formula: a CaO SiO₂ b AI₂O₃ c H₂O d X₂O e WO

In this formula X refers to an alkali metal ion, in particular sodium or potassium, and W refers to an alkaline earth metal. The variables a, b, c, d and e refer to the relative molar proportions of the units with respect to SiC>2 and are preferably in the following ranges:

0.5 < a < 2.2 preferably 1.5 < a < 2.0

0 < b < 1 preferably 0 < b < 0.1

1 < c < 6 preferably 1 < c < 6.0

0 < d < 1 preferably 0 < d < 0.2

0 < e < 2 preferably 0 < e < 0.1.

The particles of the C-S-H can e.g. be characterized by electron microscopy (TEM/SEM) and the molar ratios of the respective elements can be determined using EDX elemental analysis in an electron microscope like TEM or SEM.

In the combination of the invention, and likewise in the products and processes of the second, third and fourth aspects of the invention, the weight ratio of the amount of organic polymer P of component A to the amount of calcium silicate hydrate in component B is generally in the range of 800:1 to 10:1 , frequently in the range of 800:1 to 20:1 , in particular in the range of 500:1 to 10:1 or in the range of or 500:1 to 20:1 , more particularly in the range of 200:1 to 10:1 or in the range of 200:1 to 20:1 and especially in the range of 150:1 to 20:1 or in the range of 150:1 to 30:1 or in the range of 100:1 to 30:1. The CSH may be a stabilized aqueous dispersion of CSH particles or a powder of CSH particles. The CSH may contain up to 50% by weight of the solid constituents of organic matter including e. g. salts of sulfonic acids, such as amidosulfonic acid, organic polymer dispersants, monosaccharides, fruit acids and salts thereof, such as glucose, galactose, citric acid, gluconic acid or tartaric acid or salts thereof. The total amount of such stabilizing agents will typically not exceed 70% by weight of the total amount of solid matter in the component B and is typically in the range of 5 to 70% by weight. In particular, the mass ratio of calcium silicate hydrate and organic matter is usually at least 1 : 1 and frequently in the range of 1 :1 to 19:1.

The CSH is typically obtained by pozzolanic reaction of calcium hydroxide and silicic acid or SiC>2 which can be summarized in abbreviated notation of cement chemist as follows: CS + SH - CSH or by reaction of soluble salts such as calcium nitrate or water glass (e.g. sodium silicate).

Calcium-silicate-hydrate (also named as C-S-H) can be obtained preferably by reaction of a calcium compound with a silicate compound, preferably in the presence of a polycarboxylate ether (PCE). Such products containing calcium-silicate-hydrate are for example described in WO 2010/026155 A1 , EP 14198721 , WO 2014/114784 or WO 2014/114782.

C-S-H may be provided, e.g., as low-density C-S-H, C-S-H gel, or C-S-H seeds. Preferably, the seed size of the C-S-H is small and can also be adjusted for example by milling of C-S-H. C-S-H seeds having an average diameter of less the 10 pm, preferably less than 2 pm, and in particular of less than 1 pm are preferred. The particle size, referred to, is determined by laser diffraction and data analysis according to Mie-theory according ISO13320:2009.

The component B may be provided in solid form or in liquid form. When provided as solid, the component B is preferably in powder from containing the C-S-H particles. A suitable liquid form of the component B may be an aqueous solution or gel or an aqueous suspension of the C-S-H particles.

The water content of the component B in powder form is preferably from 0.1 weight % to 5.5 weight % with respect to the total weight of the powder sample. Said water content is measured by putting a sample into a drying chamber at 80 °C until the weight of the sample becomes constant. The difference in weight of the sample before and after the drying treatment is the weight of water contained in the sample. The water content (%) is calculated as the weight of water contained in the sample divided with the weight of the sample.

The component B may preferably be provided as an aqueous suspension. The water content of the aqueous suspension is preferably from 10 to 95% by weight, preferably from 40 to 90% by weight, more preferably from 50 to 85% by weight, in each case the percentage is given with respect to the total weight of the aqueous suspension sample. The water content is determined in an analogous way as described in the before standing text by use of a drying chamber.

The solid content of the liquid form is usually in the range of from 1 to 60% by weight, preferred from 5 to 50% by weight, more preferred from 7 to 40% by weight, based on the total weight of the liquid form. The solid content of the liquid form can be determined by drying to constant weight at 150 °C in a drying oven, with the weight difference found being regarded as the proportion of water (including bound water of solids in the suspension). When applied in liquid form, the hardening accelerator A is preferably an aqueous suspension.

Usually, a suspension containing the calcium-silicate-hydrate in finely dispersed form is obtained from the reaction of the calcium compound with the silicate compound. The suspension effectively accelerates the hardening process of hydraulic binders, in particular of ordinary Portland Cement. The suspension can be dried in a conventional manner, for example by spray drying or drum drying to give a powder.

Typically the calcium-silicate-hydrate in the composition is present in the form of one or more more of the following crystalline forms: foshagite, hillebrandite, xonotlite, nekoite, clinotobermorite , 9A-tobermorite (riversiderite), 11 A-tobermorite, 14 A-tobermorite (plombierite), jennite, metajennite, calcium chondrodite, afwillite, O-C2SH, dellaite, jaf- feite, rosenhahnite, killalaite and/or suolunite. More preferably the calcium-silicate-hydrate in the composition, preferably aqueous hardening accelerator suspension, is xonotlite, 9A - tobermorite (riversiderite), 11 A - tobermorite, 14 A - tobermorite (plombierite), jennite, metajennite, afwillite and/or jaffeite.

In one embodiment of the present invention, the component B is provided in liquid form, wherein the average particle size d(50) of the CSH particles is smaller than 5 pm, preferably smaller than 2 pm, more preferably smaller than 1 pm, and in particular smaller than 500 nm, the particle size being measured by light scattering with a Master- Sizer® 3000 from the company Malvern according to DIN ISO13320:2009. In a preferred embodiment of the present invention, the component B is provided in liquid form, wherein the average particle size d(50) of the CSH particles is smaller than 2 pm, more preferably smaller than 1 pm, and in particular smaller than 500 nm, the particle size being measured by light scattering with a MasterSizer® 3000 from the company Malvern according to DIN ISO13320:2009.

In one embodiment of the present invention, the C-S-H is provided in the form of powder particles having a diameter of less than 150 pm, wherein said powder particles comprise calcium-silicate-hydrate primary particles having a diameter of less than 200 nm, or in the form of particles having a particle size distribution characterized by a d(50) value of < 200 nm.

Without wishing to being bound by any theory, it is believed that small size particles of calcium-silicate-hydrate are especially effective as hardening accelerator.

In one embodiment of the present invention, the component B comprises a calcium-silicate-hydrate, which is obtainable in the form of a suspension by a process a) comprising the reaction of a water-soluble calcium compound with a water-soluble silicate compound, the reaction of the water-soluble calcium compound with the water-soluble silicate compound being carried out in the presence of an aqueous solution which contains at least one polymeric dispersant, which contains anionic and/or anionogenic groups and polyether side chains, preferably poly alkylene glycol side chains, or by a process P) comprising the reaction of a calcium compound, preferably a calcium salt, most preferably a water-soluble calcium salt, with a silicon dioxide containing component under alkaline conditions, wherein the reaction is carried out in the presence of an aqueous solution of at least one polymeric dispersant, which contains anionic and/or anionogenic groups and polyether side chains, preferably polyalkylene glycol side chains. Examples for the processes a) and ) are given in the international patent application published as WO 2010/026155 A1 .

To obtain the calcium- silicate-hydrate as a powder product, the suspension obtainable from said processes a) or P) is dried in a further step in a conventional manner, for example by spray drying.

In one embodiment of the present invention, the component B comprises a calcium-silicate-hydrate, which is obtainable in the form of a suspension by a process a-1 ) in which the water-soluble calcium compound is selected from calcium hydroxide and/or calcium oxide and the water-soluble silicate compound is selected from an alkali metal silicate with the formula m SiO₂ ■ n M₂O, wherein M is Li, Na, K or NH4 or mixtures thereof, m and n are molar numbers and the ratio of m:n is from about 2.0 to about 4, provided that in the case the component B being a powder product, the product in the form of a suspension obtainable from said process a-1 ) is dried in a further step in order to obtain the powder product. Generally, the calcium hydroxide can also be produced from a calcium hydroxide forming compound, e.g. from calcium carbide which upon contact with water will release acetylene and calcium hydroxide. Examples for the processes a), a-1 ), and ) are given in the international patent application published as WO 2010/026155 A1.

In one other embodiment of the present invention, the component B comprises semiordered C-S-H with a crystallite size of less than 15 nm and at least one polymeric dispersant. Such a material is obtainable for example by a process y ) by wet milling of C-S-H produced under hydrothermal conditions and where the milling was performed in presence of a water-soluble dispersant. Examples for the composition containing semiordered C-S-H and a polymeric dispersant are given in the international patent application published as WO 2018/154012 A1 .

The mineral constituent of the CSH is typically essentially free of cement clinker and/or ettringite. Here, “essentially free” means less than 10% by weight or less than 5% by weight, preferably less than 1 % by weight and in particular 0% by weight, in each case based on the total weight of the mineral constituents of the CSH.

In one embodiment of the present invention, the component B comprises a calcium-sili- cate-hydrate, which is a suspension or which is a powder product and in which before the drying step to obtain the powder product in the case a) at least one polymeric dispersant, which has anionic and/or anionogenic groups and polyether side chains, preferably poly alkylene glycol side chains, is added to the product in the form of a suspension obtained from the process a), P), y ), or a-1 ) or in the case b) at least one sulfonic acid compound of the formula (I)

in which

A¹ is NH₂, NHMe, NMe₂, N(CH₂-CH₂-OH)₂, CH₃, C₂H₅, CH₂-CH₂-OH, phenyl, or p- CHs-phenyl, and

Kⁿ⁺ is an alkali metal cation or a cation selected from the group of Ca²⁺, Mg²⁺, Sr²⁺, Ba²⁺, Zn²⁺, Fe²⁺, Fe³⁺, Al³⁺, Mn²⁺ and Cu²⁺ and n is the valency of the cation; was added to the product in the form of a suspension obtained from the process a), P), y ), or a-1 ).

The valency of the cation means in particular its number of cationic charges, like for example if Kⁿ⁺ is Mg²⁺ then the valency of the magnesium ion is 2 (n=2). Preferably A¹ is NH2, CH3 and/or phenyl. Preferably Kⁿ⁺ is Ca²⁺.

In the case a) the at least one polymeric dispersant, which has anionic and/or aniono- genic groups and polyether side chains, preferably poly alkylene glycol side chains, serves as a drying aid added to the suspensions obtained by the processes a), ) or a - 1 ) before drying said suspensions. Examples of the case a) are given in the international patent application published as WO 2012/143205.

In the case b) the sulfonic acid compound of the formula (I) serves as a drying aid added to the suspensions obtained by the processes a), P), y ), or a-1 ) before drying said suspensions.

In addition to the CSH, the component B may contain stabilizing agents, which particularly comprise one or more organic polymeric dispersants. The polymeric dispersants are typically water-soluble, i. e. they are selected from organic polymer which at 20 C and atmospheric pressure have a solubility in water of at least 10 gram per liter, in particular at least 20 gram per liter and especially at least 50 gram per liter. The polymer dispersant typically comprise structural units having anionic or anionogenic groups and/or structural units having polyether side chains. In particular the dispersant comprises at least one polymer obtained by polymerizing at least one monomer having at least one anionic or anionogenic group and at least one monomer comprising at least one polyether side chain.

Preference is given to polymer dispersants containing relatively polyether long side chains with a molecular weight of in each case at least 200 g/mol, more preferably at least 400 g/mol in varying distances on the main chain. Lengths of these side chains are often identical, but may also differ greatly from one another, for instance, in the case polyether macromonomers containing side chains of different lengths are copolymerized. Polymers of these kinds are obtainable, for example, by radical polymerization of acid monomers and polyether macromonomers. An alternative route to comb polymers of this kind is the esterification and/or amidation of poly(meth)acrylic acid and similar (co)polymers, such as acrylic acid/maleic acid copolymers, for example, with suitable monohydroxy-functional or monoamino-functional polyalkylene glycols, respectively, preferably alkyl polyethylene glycols. Comb polymers obtainable by esterification and/or amidation of poly(meth)acrylic acid are described for example in EP 1138697B1.

The average molecular weight Mw of said water-soluble polymer dispersants is 5,000 g/mol to 200,000 g/mol, preferably 10,000 g/mol to 80,000 g/mol, in particular 20,000 g/mol to 70,000 g/mol, as determined by gel permeation chromatography (GPC). The average molecular weight of the polymers was analyzed by means of GPC (column combinations: OH-Pak SB-G, OH-Pak SB 804 HQ and OH-Pak SB 802.5 HQ from Shodex, Japan; eluent: 80 vol% aqueous solution of HCO2NH4 (0.05 mol/l) and 20 vol% acetonitrile; injection volume 100 pl; flow rate 0.5 ml/min). Calibration for the purpose of determining the average molar mass was carried out with linear polyethylene oxide) standards and polyethylene glycol standards.

The polymeric dispersant preferably meets the requirements of industrial standard EN 934-2 (February 2002).

The relative amount of CSH to the stabilizing agent is typically in the range of 20:1 to 1 :1.5, in particular in the range of 10:1 to 1 :1 , especially in the range of 5:1 to 1 :1.

In one embodiment, the polymeric dispersant has at least one structural unit of the general formulae (la), (lb), (Ic) and/or (Id), where the structural units (la), (lb), (Ic) and (Id) are able to be identical or different within a single polymer molecule and also between various polymer molecules:

in which

R¹ is H or an unbranched or branched C1-C4 alkyl group, CH2COOH or CH2CO-X- R², preferably H or CH3;

X is NH-(C_nH2n), O(C_nH2n) with n = 1 , 2, 3 or 4, where the nitrogen atom or the oxygen atom is bonded to the CO group, or is a chemical bond, preferably X is chemical bond or O(C_nH2n); R² is OM, PO3M2, or O-PO3M2, with the proviso that X is a chemical bond if R² is OM;

in which

R³ is H or an unbranched or branched C1-C4 alkyl group, preferably H or CH3; n is 0, 1 , 2, 3 or 4, preferably 0 or 1 ;

R⁴ is PO3M2, or O-PO3M2;

in which

R⁵ is H or an unbranched or branched C1-C4 alkyl group, preferably H;

Z is O or NR⁷, preferably O;

R⁷ is H, (CnH_2n)-OH, (CnH₂n)-PO₃M2, (CnH₂n)-OPO₃M2, (C₆H4)-PO₃M2, or (C₆H4)-OPO₃M2, and n is 1 , 2, 3 or 4, preferably 1 , 2 or 3;

in which

R⁶ is H or an unbranched or branched C1-C4 alkyl group, preferably H;

Q is NR⁷ or O, preferably O;

R⁷ is H, (CnH_2n)-OH, (CnH₂n)-PO₃M2, (CnH₂n)-OPO₃M2, (C₆H4)-PO₃M2, or (C₆H4)-OPO₃M2, n is 1 , 2, 3 or 4, preferably 1 , 2 or 3; and each M independently of any other is H or a cation equivalent.

In one embodiment of the present invention, the comb polymer comprises as units having a polyether side chain at least one structural unit of the general formulae (Ila), (lib), (He) and/or (lid):

in which

R¹⁰, R¹¹ and R¹² independently of one another are H or an unbranched or branched C1-C4 alkyl group;

Z is O or S;

E is an unbranched or branched Ci-Ce alkylene group, a cyclohexylene group, CH2-C6H10, 1 ,2-phenylene, 1 ,3-phenylene or 1 ,4-phenylene;

G is O, NH or CO-NH; or

E and G together are a chemical bond;

A is C_XH2X with x = 2, 3, 4 or 5, preferably 2 or 3, or is CH2CH(C6Hs); n is 0, 1 , 2, 3, 4 or 5, preferably 0, 1 or 2; a is an integer from 2 to 350, preferably 5 to 150;

R¹³ is H, an unbranched or branched C1-C4 alkyl group, CO-NH2 and/or COCH3;

in which

R¹⁶, R¹⁷ and R¹⁸ independently of one another are H or an unbranched or branched C1-C4 alkyl group;

E is an unbranched or branched Ci-C₆ alkylene group, a cyclohexylene group, CH2-C6H10, 1 ,2-phenylene, 1 ,3-phenylene, or 1 ,4-phenylene, or is a chemical bond;

A is C_XH2X with x = 2, 3, 4 or 5, preferably 2 or 3, or is CH2CH(C6Hs); n is 0, 1 , 2, 3, 4 and/or 5, preferably 0, 1 or 2;

L is C_XH2X with x = 2, 3, 4 or 5, preferably 2 or 3, or is CH2-CH(C6Hs); a is an integer from 2 to 350, preferably 5 to 150; d is an integer from 1 to 350, preferably 5 to 150;

R¹⁹ is H or an unbranched or branched C1-C4 alkyl group;

R²⁰ is H or an unbranched C1-C4 alkyl group;

in which

R²¹, R²² and R²³ independently of one another are H or an unbranched or branched C1-C4 alkyl group;

W is O, NR²⁵, or is N;

Y is 1 if W = O or N R²⁵, and is 2 if W = N ;

A is C_XH2X with x = 2, 3, 4 or 5, preferably 2 or 3, or is CH2CH(C6Hs); a is an integer from 2 to 350, preferably 5 to 150;

R²⁴ is H or an unbranched or branched C1-C4 alkyl group; and

R²⁵ is H or an unbranched or branched C1-C4 alkyl group;

in which

R⁶ is H or an unbranched or branched C1-C4 alkyl group;

Q is NR¹⁰, N or O;

Y is 1 if W = O or NR¹⁰ and is 2 if W = N;

R¹⁰ is H or an unbranched or branched C1-C4 alkyl group; and

A is C_XH2X with x = 2, 3, 4 or 5, preferably 2 or 3, or is CH2C(C6Hs)H;

R²⁴ is H or an unbranched or branched C1-C4 alkyl group;

M is H or a cation equivalent; and a is an integer from 2 to 350, preferably 5 to 150.

In one embodiment of the present invention, the comb polymer comprises a polyether side chain comprising: (a) at least one structural unit of the formula (Ila) in which R¹⁰ and R¹² are H, R¹¹ is H or CH3, E and G together are a chemical bond, A is C_xH2x with x = 2 and/or 3, a is

3 to 150, and R¹³ is H or an unbranched or branched C1-C4 alkyl group; and/or

(b) at least one structural unit of the formula (lib) in which R¹⁶ and R¹⁸ are H, R¹⁷ is H or CH3, E is an unbranched or branched Ci-Ce alkylene group, A is C_xH2x with x =

2 and/or 3, L is C_xH2x with x = 2 and/or 3, a is an integer from 2 to 150, d is an integer from 1 to 150, R¹⁹ is H or an unbranched or branched C1-C4 alkyl group, and R²⁰ is H or an unbranched or branched C1-C4 alkyl group; and/or

(c) at least one structural unit of the formula (He) in which R²¹ and R²³ are H, R²² is H or CH3, A is C_XH2X with x = 2 and/or 3, a is an integer from 2 to 150, and R²⁴ is H or an unbranched or branched C1-C4 alkyl group; and/or

(d) at least one structural unit of the formula (lid) in which R⁶ is H, Q is O, R⁷ is (C_nH2n)-O-(AO)_a-R⁹, n is 2 and/or 3, A is C_xH2x with x = 2 and/or 3, a is an integer from 1 to 150 and R⁹ is H or an unbranched or branched C1-C4 alkyl group.

In one embodiment of the present invention, the comb polymer comprises at least one structural unit of the formula (Ila) and/or (He).

In one embodiment of the present invention, the comb polymer comprises units of the formulae (I) and (II).

In one embodiment of the present invention, the comb polymer comprises structural units of the formulae (la) and (Ila).

In one embodiment of the present invention, the comb polymer comprises structural units of the formulae (la) and (He).

In one embodiment of the present invention, the comb polymer comprises structural units of the formulae (Ic) and (Ha).

In one embodiment of the present invention, the comb polymer comprises structural units of the formulae (la), (Ic) and (Ha).

In one embodiment of the present invention, the comb polymer comprises (i) anionic or anionogenic structural units derived from acrylic acid, methacrylic acid, maleic acid, hydroxyethyl acrylate phosphoric acid ester, and/or hydroxyethyl methacrylate phosphoric acid ester, hydroxyethyl acrylate phosphoric acid diester, and/or hydroxyethyl methacrylate phosphoric acid diester, and (ii) polyether side chain structural units derived from C1-C4 alkyl-polyethylene glycol acrylic acid ester, polyethylene glycol acrylic acid ester, C1-C4 alkyl-polyethylene glycol methacrylic acid ester, polyethylene glycol methacrylic acid ester, C1-C4 alkyl-polyethylene glycol acrylic acid ester, polyethylene glycol acrylic acid ester, vinyl oxy-C2-C4 alkylene-polyethylene glycol, vinyl oxy-C2-C4 alkylene-poly- ethylene glycol C1-C4 alkyl ether, allyloxypolyethylene glycol, allyloxypolyethylene glycol C1-C4 alkyl ether, methallyloxy-polyethylene glycol, methallyloxy-polyethylene glycol C1-C4 alkyl ether, isoprenyloxy-polyethylene glycol and/or isoprenyloxy-polyethylene glycol C1-C4 alkyl ether.

In one embodiment of the present invention, the comb polymer comprises structural units (i) and (ii) derived from hydroxyethyl acrylate phosphoric acid ester and/or hydroxyethyl methacrylate phosphoric acid ester and (ii) C1-C4 alkyl-polyethylene glycol acrylic acid ester and/or C1-C4 alkyl-polyethylene glycol methacrylic acid ester; or acrylic acid and/or methacrylic acid and (ii) C1-C4 alkyl-polyethylene glycol acrylic acid ester and/or C1-C4 alkyl-polyethylene glycol methacrylic acid ester; or acrylic acid, methacrylic acid and/or maleic acid and (ii) vinyloxy-C2-C4 alkylenepolyethylene glycol, allyloxy-polyethylene glycol, methallyloxy-polyethylene glycol and/or isoprenyloxy-polyethylene glycol.

In this connection, the comb polymer preferably comprises structural units (i) and (ii) derived from hydroxyethyl methacrylate phosphoric acid ester and (ii) C1-C4 alkyl-polyethylene glycol methacrylic acid ester or polyethylene glycol methacrylic acid ester; or methacrylic acid and (ii) C1-C4 alkyl-polyethylene glycol methacrylic acid ester or polyethylene glycol methacrylic acid ester; or acrylic acid and maleic acid and (ii) vinyloxy-C2-C4 alkylene-polyethylene glycol or acrylic acid and maleic acid and (ii) isoprenyloxy-polyethylene glycol or acrylic acid and (ii) vinyloxy-C2-C4 alkylene-polyethylene glycol or acrylic acid and (ii) isoprenyloxy-polyethylene glycol or acrylic acid and (ii) methallyloxy-polyethylene glycol or maleic acid and (ii) isoprenyloxy-polyethylene glycol or maleic acid and (ii) allyloxy-polyethylene glycol or maleic acid and (ii) methallyloxy-polyethylene glycol.

In one embodiment of the present invention, the molar ratio of the structural units (I) : (II) is 1 :4 to 15:1 , more particularly 1 :1 to 10:1.

In one embodiment of the present invention, the comb polymer is a phosphorylated polycondensation product comprising structural units (III) and (IV):

in which T is a substituted or unsubstituted phenyl or naphthyl radical or a substituted or unsubstituted heteroaromatic radical having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O and S; n is 1 or 2;

B is N, NH or O, with the proviso that n is 2 if B is N and with the proviso that n is 1 if B is NH or O;

A is an unbranched or branched alkylene with 2 to 5 carbon atoms or CH₂CH(C₆H₅); a is an integer from 1 to 300;

R²⁵ is H, a branched or unbranched Ci to Cw alkyl radical, Cs to Cs cycloalkyl radical, aryl radical, or heteroaryl radical having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O and S; where the structural unit (IV) is selected from the structural units (IVa) and (IVb):

in which

D is a substituted or unsubstituted phenyl or naphthyl radical or a substituted or unsubstituted heteroaromatic radical having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O and S;

E is N, NH or O, with the proviso that m is 2 if E is N and with the proviso that m is 1 if E is NH or O;

A is an unbranched or branched alkylene with 2 to 5 carbon atoms or CH₂CH(C₆H₅); b is an integer from 0 to 300;

M independently at each occurrence is H or a cation equivalent;

in which

V is a substituted or unsubstituted phenyl or naphthyl radical and is optionally substituted by 1 or two radicals selected from R⁸, OH, OR⁸, (CO)R⁸, COOM, COOR⁸, SO3R⁸ and NO₂;

R⁷ is COOM, OCH₂COOM, SO₃M or OPO₃M₂; M is H or a cation equivalent; and

R⁸ is C1-C4 alkyl, phenyl, naphthyl, phenyl-Ci-C4 alkyl or C1-C4 alkylphenyl.

In this connection, in formula III, T is preferably a substituted or unsubstituted phenyl radical or naphthyl radical, A is C_xH2x with x = 2 and/or 3, a is an integer from 1 to 150, and R²⁵ is H, or a branched or unbranched Ci to C10 alkyl radical.

In this connection, in formula IVa, D is preferably a substituted or unsubstituted phenyl radical or naphthyl radical, E is NH or O, A is C_xH2x with x = 2 and/or 3, and b is an integer from 1 to 150.

In this connection, T and/or D are preferably phenyl or naphthyl which is substituted by 1 or 2 C1-C4 alkyl, hydroxyl or 2 C1-C4 alkoxy groups.

In this connection V is preferably phenyl or naphthyl which is substituted by 1 or 2 C1-C4 alkyl, OH, OCH₃ or COOM, and R⁷ is COOM or OCH₂COOM.

In this connection, the polycondensation product comprises a further structural unit (V) of the formula

(V)

in which

R⁵ and R⁶ may be identical or different and are H, CH3, COOH or a substituted or unsubstituted phenyl or naphthyl group or are a substituted or unsubstituted heteroaromatic group having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O and S.

In one embodiment of the present invention, R⁵ and R⁶ may be identical or different and are H, CH3, or COOH, more particularly H, or one of the radicals R⁵ and R⁶ is H and the other is CH3.

In one embodiment of the present invention, the molar weight of the polyether side chains is >200 g/mol, preferably >300 g/mol and <6000 g/mol, preferably <5000 g/mol. In one embodiment of the present invention, the molecular weight of the polyether side chains is in the range from 200-6000 g/mol, more particularly 500-5000 g/mol and more preferably 1000-5000 g/mol. In one embodiment of the present invention, where the charge density of the comb polymer is in the range from 0.5 meq/g -5 meq/g polymer, preferably 0.6 meq/g - 3 meq/g polymer.

In a further embodiment, the water-soluble polymer is a copolymer comprising sulfo group containing units and/or sulfonate group-containing units and carboxylic acid and/or carboxylate group- containing units. In an embodiment, the sulfo or sulfonate group containing units are units derived from vinylsulfonic acid, methallylsulfonic acid, 4-vinylphenylsulfonic acid or are sulfonic acid-containing structural units of formula

wherein

R¹ represents hydrogen or methyl

R², R³ and R⁴ independently of each other represent hydrogen, straight or branched Ci-Ce-alkyl or Ce-Ci4-aryl,

M represents hydrogen, a metal cation, preferably a monovalent or divalent metal cation, or an ammonium cation a represents 1 or 1 /valency of the cation, preferably Vi or 1 .

Preferred sulfo group containing units are derived from monomers selected from vinylsulfonic acid, methallylsulfonic acid, and 2-acrylamido-2-methylpropylsulfonic acid (AMPS) with AMPS being particularly preferred.

The carboxylic acid or carboxylate containing units are preferably derived from monomers selected from acrylic acid, methacrylic acid, 2-ethylacrylic acid, vinyl acetic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and in particular acrylic acid and methacrylic acid.

The sulfo group containing copolymer in general has a molecular weight M_w in the range from 1000 g/mol to 50,000 g/mol, preferably 1500 g/mol to 30,000 g/mol, as determined by aqueous gel permeation chromatography. In an embodiment, the molar ratio between the sulfo group containing units and carboxylic acids containing units is, in general, in the range from 5:1 to 1 :5, preferably 4:1 to 1 :4.

Preferably the (co)polymer dispersant having carboxylic acid groups and/or carboxylate groups and sulfonic acid groups and/or sulfonate groups has a main polymer chain of carbon atoms and the ratio of the sum of the number of carboxylic acid groups and/or carboxylate groups and sulfonic acid groups and/or sulfonate groups to the number of carbon atoms in the main polymer chain is in the range from 0.1 to 0.6, preferably from 0.2 to 0.55. Preferably said (co)polymer dispersant is obtainable from a free-radical (co)polymerisation and the carboxylic acid groups and/or carboxylate groups are derived from monocarboxylic acid monomers. Preferred is a (co)polymer, which can be obtained from a free-radical (co)polymerisation and the carboxylic acid groups and/or carboxylate groups are derived from the monomers acrylic acid and/or methacrylic acid and the sulfonic acid groups and/or sulfonate groups are derived from 2-acrylamido-2- methylpropanesulfonic acid. Preferably the weight average molecular weight M_w of the (co)polymer(s) is from 8,000 g/mol to 200,000 g/mol, preferably from 10,000 to 50,000 g/mol. The weight ratio of the (co)polymer or (co)polymers to the calcium silicate hydrate is preferably from 1/100 to 4/1 , more preferably from 1/10 to 2/1 , most preferably from 1/5 to 1/1.

In one embodiment of the present invention, the water-soluble polymer dispersant is selected from copolymers, comprising the structural units of formula (la) and (Ila), in particular copolymers, comprising structural units derived from acrylic and/or methacrylic acid and ethoxylated hydroxyalkylvinylether, such as ethoxylated hydroxybutyl- vinylether; copolymers, comprising the structural units of formula (la), (Id) und (Ila), in particular copolymers, comprising structural units derived from acrylic acid and/or methacrylic acid, maleic acid, and ethoxylated hydroxyalkylvinylether, such as ethoxylated hydroxybutyl-vinylether; copolymers, comprising the structural units of formula (la) und (He), in particular copolymers, comprising structural units derived from acrylic and/or methacrylic acid and esters of the acrylic and/or methacrylic acid with polyethylenglykol or polyethylenglykol, being endcapped with Ci-Ci2-alkyl; polycondensation produkts, comprising the structural units of formula (III), (IVa) and (V), in particular condensation products of ethoxylated phenol, phenoxy-C2-Ce- alkanolphosphate and formaldehyde; homopolymers, comprising sulfo- and/or sulfonate groups-containing units or carbon acid- and/or carboxylate groups-containing units; copolymers, comprising sulfo- and/or sulfonate groups-containing units and carbon acid- and/or carboxylate groups-containing units; and/or polyacrylic acid; and salts thereof and combinations of two or more of these water-soluble polymers.

For the purpose of the invention, it was found beneficial if the combination further comprises at least one salt of a sulfonic acid. Examples of such compounds include salts of Ci-C4-alkylsulfonic acid, such as salts of methane sulfonic acid and salts of the monoamides of sulfonic acid, such as the salts of amidosulfonic acid, the salts of N-Ci- C4-alkylamiodsulfonic acid and the salts of N,N-di-Ci-C4-alkylamiodsulfonic acid. Suitable salts are in particular the alkalimetal salts and the earth alkali metal salts, in particular, the sodium, potassium and calcium salts. In particular the salt of the sulfonic acid is a salt of amidosulfonic acid (H2N-SO3H), in particular the calcium salt thereof. The amount of the salt of a sulfonic acid is typically in the range of 0.01 to 5% by weight, in particular 0.05 to 2% by weight, based on the total weight of the polymer P of component A and the CSH of component B.

For the purpose of the invention, it was found beneficial if the combination does not comprise more than 5% by weight, in particular less than 2% by weight, based on the weight of the organic polymer P, of water-soluble polymers having carboxylic acid groups and/or sulfonic acid groups, because it was found by the inventors that these polymers may cause a retardation of the setting. Typical polymers having such a retardation effect include water-soluble polymers comprising more than 40% by weight of ethylenically unsaturated monomers bearing a carboxyl group or a sulfonic acid group and polycondensation products of aryl sulfonic acids with formaldehyde, such as polycondensation products of napthalene sulfonic acid or phenolsulfonic acid with formaldehyde.

From their production processes, the polymer P of component A is typically obtained as an aqueous polymer dispersion of the polymer P. Likewise, the calcium silicate hydrate of component B is typically obtained as an aqueous suspension of CSH particles.

For the use of the present invention, the components A and B may be used according to the following options (i) to (v):

(i) as separate formulations of an aqueous dispersion of the polymer P and the component B in the form of an aqueous suspension or solution of the CSH particles,

(ii) as an aqueous formulation containing both the polymer P and the component B in admixture; (iii) as a combination of a polymer powder of the polymer P and the component B in the form of aqueous suspension of the CSH particles;

(iv) as a combination of an aqueous polymer dispersion of the polymer P and the component B in the form of powder of the CSH particles;

(v) as a powder containing both the components A and B. Such a powder can be obtained by mixing a powder obtained from an aqueous dispersion of the polymer P and the component B in the form of a powder or by co-spray drying of an aqueous dispersion of the polymer P and the component B in the form of an aqueous suspension or solution.

Amongst the options (i) to (v), preference is given to the options (ii), (iii), (iv) and (v), with particular preference given to option (v).

Powders containing the components A or the component B can be obtained by spraydrying the aqueous dispersions of the polymer P and the aqueous suspensions of the CSH particles, respectively. Spray drying can be carried by analogy to a well known spray drying procedures, optionally the presence of spray drying agents.

For example, spray drying of the aqueous polymer dispersion of the vinylacetate-eth- ylene copolymer of the component A is typically carried out in the presence of a polymeric spray drying agent, such as polycarboxylic acids, arylsulfonic acid formaldehyde condensation products, cellulose, degraded starch or polyvinyl alcohols. The amount of spray drying agent is typically in the range of 1 to 20% by weight, based on the vi- nylacetate-ethylene copolymer in the polymer dispersion. Preference is given to spray drying aids selected from the group consisting of cellulose, degraded starch and partially or fully hydrolyzed polyvinyl alcohols. Even more preference is given to partially or fully hydrolyzed polyvinyl alcohols, in particular those having a degree of hydrolysis of at least 95% and/or a Hoeppler viscosity of in each case of preferably in the range 1 to 50 mPas and more preferably 2 to 20 mPas as determined to DIN 53015, Hoeppler method, at 20° C, in 4% aqueous solution.

The thus obtained polymer powder may be formulated with anti-blocking agents, in particular selected from inorganic anti-blocking agents, such as limestone powder, kaolin powder or talcum powder. The amount of these antiblocking agent is typically in the range of 2 to 20% by weight, based on the total weight of the polymer powder.

For spray drying of the aqueous suspensions of the CSH particles typically a suspension is used which contains a polymeric dispersant as described above. It has been found beneficial, if spray drying is carried out in the presence of a further stabilization agent, which is preferably selected from the salts of amidosulfonic acid, monosaccharides, fruit acids and salts thereof as well as combinations thereof. In Further stabilization agents are typically used in an amount of 1 to 100% by weight, in particular 2 to 50% by weight, based on the total weight of the calcium-silicate hydrate present in the suspension. In particular, the further stabilization agent comprises a salt of amidosulfonic acid, e. g. an alkalimetal salt, such as sodium or potassium amidosulfonate, or an earth alkali metal salt, such as calcium amidosulfonate (= Ca(SC>3NH2)2).

In particular, it is preferred to provide a powder containing both the components A and B and optionally a spray drying agent, as described in the context of the spray drying of the polymer dispersion, optionally polymeric dispersant as described in the context of the aqueous dispersions of the CSH particles, and optionally a further stabilization agent, which is preferably selected from the salts of amidosulfonic acid, monosaccharides, fruit acids and salts thereof as well as combinations thereof.

Therefore, a particular fourth aspect of the invention relates to powdery compositions containing both the components A and B. In particular, the forth aspect of the invention relates to powdery compositions, consisting of a) the organic polymer P of component A b) the component B containing the calcium silicate hydrate particles, preferably in combination with the polymeric dispersant as described in the context of the aqueous suspensions of the CSH particles, d) optionally up to 30% by weight, in particular 1 to 30% by weight, based on the total dry matter of the powdery composition, of further ingredients, which are in particular selected from spray drying agent, as described in the context of the spray drying of the polymer dispersion, preferably non-ionic polymers having a plurality of hydroxyl groups, in particular a polyvinyl alcohol, and optionally a further stabilization agent, which is preferably selected from the salts of amidosulfonic acid, monosaccharides, fruit acids and salts thereof as well as combinations thereof; wherein the weight ratio of the organic polymer of component A to the amount of CSH in component B is in the range of 800:1 to 10:1 , frequently in the range of 800:1 to 20:1 , in particular in the range of 500:1 to 10:1 or in the range of or 500:1 to 20:1 , more particularly in the range of 200:1 to 10:1 or in the range of 200:1 to 20:1 and especially in the range of 150:1 to 20:1 or in the range of 150:1 to 30:1 or in the range of 100:1 to 30:1 and where the weight ratio of the organic polymer of component A to the total amount of dry matter of component B is preferably in the range of 400:1 to 5:1 , frequently in the range of 400:1 to 10:1 , in particular in the range of 250:1 to 5:1 or in the range of or 250:1 to 10:1 , more particularly in the range of 100:1 to 5:1 or in the range of 100:1 to 10:1 and especially in the range of 75:1 to 10:1 or in the range of 75:1 to 15:1 or in the range of 50: 1 to 15: 1 .

In particular, the fourth aspect of the invention relates to powdery compositions containing a) 65 to 98.8% by weight, in particular 72 to 98% by weight, based on the total dry matter of the powdery composition, of at least one organic polymer P; b) 0.2 to 10% by weight, in particular 0.5 to 8.0% by weight, based on the total dry matter of the powdery composition, of the dry matter of component B or 0.1 to 5.0 % by weight, in particular 0.25 to 4.0% by weight, based on the total dry matter of the powdery composition, of total amount of CSH contained in the component B; e) 1 to 30% by weight, in particular 2 to 25% by weight, based on the total dry matter of the powdery composition, of further ingredients, which are in particular selected from spray drying agent, as described in the context of the spray drying of the polymer dispersion, preferably non-ionic polymers having a plurality of hydroxyl groups, in particular a polyvinyl alcohol, and optionally one or more further stabilization agents, which are preferably selected from the salts of amidosulfonic acid, monosaccharides, fruit acids and salts thereof as well as combinations thereof; wherein the weight ratio of the organic polymer of component A to the total amount CSH in component B is preferably in the range of 200:1 to 13:1 , in particular in the range of 150:1 to 20:1 and especially in the range of 100:1 to 30:1 and where the weight ratio of the organic polymer of component A to the total amount of dry matter of component B is preferably in the range of 100:1 to 6.5:1 , in particular in the range of 75:1 to 10:1 and especially in the range of 50:1 to 15:1.

In particular, the powdery composition according to the fourth aspect of the invention further comprises at least one further ingreadient (d.1 ), (d.2) and (d.3) or any combination of said further ingredients (d.1 ), (d.2) and (d.3):

The ingredient (d.1) is selected from one or non-ionic water soluble polymers having a plurality of hydroxyyl groups. Examples of such non-ioninc water soluble polymers include, but are not limited to cellulose, degraded starch or polyvinyl alcohols and combinations thereof. Particular preference is given to polyvinylalcohols, which may be partially or completely saponified. Suitable polyvinylalcohols are those mentioned as protective colloids for the preparation of the aqueous dispersions of the vinylacetateethylene copolymers. Even more preference is given to partially or fully hydrolyzed polyvinyl alcohols having a degree of hydrolysis of at least 90% and/or a Hoeppler viscosity of in each case of preferably in the range 1 to 50 mPas and more preferably 2 to 20 mPas as determined to DIN 53015, Hoeppler method, at 20° C, in 4% aqueous solution. The amount of the non-ionic water soluble polymer having a plurality of hydroxyyl groups is typically in the range of 1 to 20% by weight, based on the total weight of the powdery composition.

The ingredient (d.2) is selected from one or more compounds OC, which are selected from monosaccharides, fruit acids and salts thereof, such as glucose, galactose, citric acid, gluconic acid or tartaric acid or salts thereof. The amount of the organic compound OC is typically in the range of 0.01 to 5% by weight, in particular 0.05 to 2% by weight, the powdery composition.

The ingredient (d.3) is selected from one or more salts of a sulfonic acid. Examples of such compounds (d.3) include salts of Ci-C₄-alkylsulfonic acid, such as salts of methane sulfonic acid and salts of the monoamides of sulfonic acid, such as the salts of amidosulfonic acid, the salts of N-Ci-C4-alkylamiodsulfonic acid and the salts of N,N- di-Ci-C4-alkylamiodsulfonic acid. Suitable salts are in particular the alkalimetal salts and the earth alkali metal salts, in particular, the sodium, potassium and calcium salts. In particular the salt of the sulfonic acid is a salt of amidosulfonic acid (H2N-SO3H), in particular the calcium salt thereof. The amount of the salt of a sulfonic acid is typically in the range of 0.01 to 5% by weight, in particular 0.05 to 2% by weight, based on the total weight of the powdery composition.

In particular, the powdery composition according to the fourth aspect of the invention does not comprise more than 5% by weight, in particular less than 2% by weight, based on the weight of the organic polymer P, of water-soluble polymers having carboxylic acid groups and/or sulfonic acid groups, e. g. water-soluble polymers comprising more than 40% by weight of ethylenically unsaturated monomers bearing a carboxyl group or a sulfonic acid group and polycondensation products of aryl sulfonic acids with formaldehyde, such as polycondensation products of napthalene sulfonic acid or phenolsulfonic acid with formaldehyde.

Preferably, the powder composition of the fourth aspect of the invention is prepared by joint spray drying of an aqueous polymer dispersion of the organic polymer P and an aqueous suspension of the component B. The optional one or more further ingredients D, may be incorporated into the powder composition during spray drying or admixed to the powder composition after joint spray drying of the aqueous polymer dispersion of the organic polymer P and an aqueous suspension of the component B. Preferably, joint spray drying is carried out in the presence of a spray drying assistant selected from non-ionic water soluble polymers having a plurality of hydroxyl groups. Examples of such non-ionic water soluble polymers include, but are not limited to cellulose, degraded starch or polyvinyl alcohols and combinations thereof. Particular preference is given to polyvinyl alcohols as described in the context of component (d.1).

The powder composition of the fourth aspect of the invention can also be prepared by mixing powders of the polymer P and powdery component B.

For producing the mineral waterproofing membranes the combination of the component A and the component B is combined with the further components which form the mineral waterproofing membrane and water to produce a slurry which can be applied to the surface for which a mineral waterproofing membrane is required. If the combination of the invention already contains water, e. g. if the polymer P is provided as an aqueous polymer dispersion optionally containing the component B, no additional water or only small amounts of water may be required to obtain the slurry.

These further components include, but are not limited to c.1 at least one mineral binder and c.2 one or more fillers and optionally further ingredients, such as accelerators.

Typically, these further components are present as powders, wherein at least 90% by weight of the particles of the respective powder have a particle size of at most 500 pm, in particular of at most 400 pm, especially of at most 300 pm.

The mineral binder is typically a hydraulic binder or latent hydraulic binder or a combination of different hydraulic binders, in particular portland cement, slag, granulated blast furnace slag, calcium sulfate, fly ash, silica flour, metakaolin, natural pozzolanas, calcined oil shale, calcium sulfoaluminate cements and/or calcium aluminate cements. Frequently, the mineral binder comprises at least on cement selected from cements classified according to EN 197-1 :2011 as CEM I or CEM II, particular a portland cement (cement of class CEM I, also termed OPC) and especially a portland cement classified as CEM I 52.5 N, CEM I 42.5 R or CEM I 52.5 R. The mineral binder may also be a combination of different hydraulic binders, e.g. a combination of portland cement, such as CEM I 52.5 N, CEM I 42.5 R or CEM I 52.5 R, and a least one of calcium aluminate cement and calcium sulfate, or a combination of portland cement, such as CEM I 52.5 N, CEM I 42.5 R or CEM I 52.5 R and a pozzolanic material such as natural pozzolan or calcined natural pozzolan optionally in combination with limestone, or a combination of portland cement with fly ash. The overall amount of the mineral binder (c.1) is preferably in the range of 10 to 45% by weight, in particular from 10 to 40% by weight, based on the total weight of the dry matter of the composition used for producing the mineral waterproofing membrane. Preferably, the relative amounts of the polymer P to the mineral binder is such that the ratio of polymer P to mineral binder is preferably in the range of 1 :3 to 2:1 .

The powdery filler (c.2) as used in the composition for producing the mineral waterproofing membrane may be any of the usual construction fillers, including mineral fillers such as rock powder and sand; recycle aggregates produced from the recycling of concrete, which is itself chiefly manufactured from mineral fillers. Mineral fillers such as powdery dolomite, granites, gravel, sandstone, limestone, basalt and the like can also be used as fillers. The present powdery filler may also include one or more organic, such as ground rubber or bitumen. The present powdery filler includes also mixtures of two or more of the above-listed fillers.

The overall amount of the powdery filler (c.2) is preferably in the range of 15 to 70% by weight, in particular from 20 to 50% by weight, based on the total weight of the dry matter of the composition used for producing the mineral waterproofing membrane.

In one embodiment, the sand is a combination of medium sand and fine sand. Fine sand in terms of the present invention is defined in accordance with DIN 4022:1987 and is sand with an equivalent diameter of 0.063-0.2 mm. Medium sand in terms of the present invention is defined in accordance with DIN 4022:1987 and is sand with an equivalent diameter of 0.2-0.63 mm. Medium sand and fine sand are preferably present in a weight ratio of from 2:1 to 1 :5, more preferably from 1 :1 to 1 :3, in particular from 1 :1.5 to 1 :3.

In a preferred embodiment, the composition for producing the mineral waterproofing membrane comprises an organic powdery recycling material, such as powdered rubber. The powdered rubber is a recycle material obtained, for example from comminuting discarded tires and the like. The powdered rubber not only reduces the amount of natural mineral aggregates, such as sand, thus allowing to preserve their pristine natural resources, but also contributes to the flexibility and elasticity and thus crack resistance of the set system. The organic powdery recycling material has preferably a particle size of at most 500 pm and typically of at least 50 pm. The organic powdery recycling material, if present, is preferably present in an amount of from 5 to 50% by weight, in particular from 10 to 40% by weight, based on the total weight of the fillers. Its amount with respect to the dry matter of the composition for producing the mineral waterproofing membrane, if present, is typically in the range of 2 to 30% by weight, in particular 5 to 25% by weight, based on the total weight of the dry matter of the composition for producing the mineral waterproofing membrane.

Typically, the components c.1 and c.2 are provided as a powdery composition C into which the components A and B of the combination of the invention and optionally water are incorporated, whereby a slurry is obtained which can be applied to the surface to which the mineral waterproofing membrane shall be applied. Upon drying and setting of the mineral binder the mineral waterproofing membrane is formed.

According to a first group of embodiments, the combination of the components A and B can be incorporated as powders containing either component A or component B or as a powder containing both components A and B into the powdery composition C which contains the mineral binder and the filler and to obtain a powdery composition. Such a composition is a so-called 1 K composition as it contains all necessary ingredients for producing the mineral waterproofing membrane. For producing the mineral waterproofing membrane said powdery composition is mixed with an amount of water necessary for hardening the mineral binder, whereby a slurry is obtained which is then applied to the surface, where the mineral waterproofing membrane is desired.

According to a second group of embodiments, a liquid formulation containing the polymer P as an aqueous polymer dispersion and further containing the component P as an aqueous suspension of calcium silicate hydrate particles and optionally a suitable organic polymer dispersant as described above is provided as a first formulation of a two-kits-of-parts formulation. As a separate formulation the powdery composition C is provided which contains the mineral binder and the filler as described above and optionally further additives. When the liquid formulation and optionally further water are incorporated into the powdery composition C, a slurry is obtained which is then applied to the surface, where the mineral waterproofing membrane is desired.

According to a third group of embodiments, an aqueous polymer dispersion of the polymer P is provided as a first part of a two-kits-of-parts formulation. As a separate formulation the powdery composition C is provided which contains the mineral binder and the filler as described above, the component B in the form of a powder as described above and optionally further additives. When the aqueous polymer dispersion and optionally further water are incorporated into this powdery composition C, a slurry is obtained which is then applied to the surface, where the mineral waterproofing membrane is desired. According to a fourth group of embodiments, an aqueous suspension of the CSH is provided as a first part of a two-kits-of-parts formulation. As a separate formulation the powdery composition C is provided which contains the mineral binder and the filler as described above, the component A in the form of a powder as described above and optionally further additives. When the aqueous polymer dispersion and optionally further water are incorporated into this powdery composition C, a slurry is obtained which is then applied to the surface, where the mineral waterproofing membrane is desired.

According to a fifth group of embodiments the combination of the components A and B is provided as a powder containing both components A and B as a first part of a two- kits-of-parts formulation. As a separate formulation the powdery composition C is provided which contains the mineral binder and the filler as described above and optionally further additives. When the first part of the two-kits of parts formulation and water are incorporated into this powdery composition C, a slurry is obtained which is then applied to the surface, where the mineral waterproofing membrane is desired.

The composition C can also comprise further additives which are typically used in the field of mineral waterproofing membranes, for example other curing accelerators, dispersants, plasticizers, water reducers, setting retarders, antifoams, retarders, shrinkage-reducing agents, freezing protection agents and/or antiefflorescence agents.

Suitable other curing accelerators are alkanolamines, preferably triisopropanolamine and/or tetrahydroxyethylethylenediamine (THEED). The alkanolamines are preferably used in an added amount of from 0.01 to 2.5% by weight, based on the weight of the hydraulic binder. When amines, in particular triisopropanolamine and tetrahydroxyethylethylenediamine, are used, synergistic effects can be found in respect of the early strength development of hydraulic binder systems, in particular cement-like systems.

Further curing accelerators are, for example, calcium hydroxide, calcium chloride, calcium formate, calcium nitrate, inorganic carbonates (e.g. sodium carbonate, potassium carbonate) and lithium carabonate. Preference is given to using calcium formate, calcium hydroxide, lithium carbonate and calcium nitrate in an amount of from 0.1 to 4% by mass based on the hydraulic binder.

Suitable setting retarders are citric acid, tartaric acid, gluconic acid, phosphonic acid, aminotrimethylenephosphonic acid, ethylenediaminotetra(methylenephosphonic) acid, diethylenetriaminopenta(methylenephosphonic) acid, in each case including the respective salts of the acids, pyrophosphates, pentaborates, metaborates and/or sugars (e.g. glucose, molasses). The advantage of the addition of setting retarders is that the open time can be controlled and in particular may be able to be extended. The setting retarders are preferably used in an amount of from 0.01 % by weight to 0.5% by weight, based on the weight of the mineral binder.

The following examples shall further illustrate the invention

Hereinafter the following abbreviations are used:

C-S-H calcium silicate hydrate

MM FT minimum film forming temperature

Mw molecular weight, weight average n.d. not determined

OPC ordinary portland cement

PVOH polyvinyl alcohol

RDP redispersible polymer powder

SDA spray drying aid s.c. solids content wt.-% % by weight

For the examples and comparative examples, the following starting materials were used:

Spray drying aids:

Spray drying aid 1 (SDA-1 ): Commercially available partially saponified polyvinyl alcohol (PVOH), which is manufactured by Kuraray and is available under the trade name Poval® 4-88.

Spray drying aid 2 (SDA-2): A polyacid based on the monomers methacrylic acid and 2-methyl-2-propene-1 -sulfonic acid. This polyacid has a molecular weight of Mw about 1400 g/mol and was synthesized as described in US 2020/0207671 A1 page 10, paragraph 0234 to paragraph 0235.

Spray drying aid 3 (SDA-3): A phenol sulfonic acid-formaldehyde condensation product with a molecular weight Mw of about 8000 g/mol was synthesized as described in WO 98/03576 A1 page 14, line 42 to page 15, line 12.

Aqueous polymer dispersions Polymer dispersion 1 (PD-1 ): Aqueous polymer dispersion of a copolymer of vinyl acetate and ethylene which is stabilized by polyvinyl alcohol as protective colloid. The dispersion has a solids content of 53% by weight. The polymer has a minimum film forming temperature (MF FT) of ~ 0°C, a glass transition temperature of below 0°C and a predominant particle size of 900 nm. An example is the polymer dispersion VINNAPAS® 550 ED from Wacker.

Polymer dispersion 2 (PD-2): Aqueous polymer dispersion of a terpolymer of vinyl acetate, ethylene, and vinyl ester. The dispersion is stabilized by surfactants and has a solids content of 59% by weight. The polymer has a minimum film forming temperature (MFFT) of ~ 0°C, a glass transition temperature of -12°C, and a predominant particle size of 300 nm. An example is the polymer dispersion VINNAPAS® 760 ED from Wacker.

Polymer dispersion 3 (PD-3): A styrene-acrylate polymer dispersion was produced by emulsion polymerization as described in WO 2013/117465 A1 : Example “Polymeri- satdispersion D” on page 19-20. The dispersion has a solids content of 57% by weight, a glass transition temperature of -13°C, and a particle size of 230 nm.

Calcium-silicate-hydrate (C-S-H) nanocrystals in suspension or powdered form:

Aqueous suspension of a stabilized calcium silicate hydrate (C-S-H-1 ):

The C-S-H suspension was prepared by wet grinding of hydrothermal calcium-silicate- hydrate according to US 2020/0231499 A1 , example S11 in table 4 on page 14.

The calculated C-S-H content of the suspension was 9.0% by weight. The molar ratio Ca/Si of the C-S-H particles was 1.77.

Powder of a stabilized calcium silicate hydrate (CSH-2):

The C-S-H suspension C-S-H-1 , which had been prepared according to

US 2020/0231499 A1 , example S11 , was dried according to the protocol of example 2 of US 2015/0344368 in the presence of sodium amidosulfonate in an amount given for entry TH1-q in table 2 of US 2015/0344368, page 16. Instead of suspension H1 the suspension of C-S-H-1 was used. The final molar Ca/Si ratio of the C-S-H particles was 1 .85. The calculated C-S-H content of the powder was 50.7% by weight.

Aqueous suspension of a stabilized calcium silicate hydrate (C-S-H-3): The C-S-H suspension CSH-3 was synthesized according to US 2015/0344368, example H2 page 17. The calculated C-S-H content was 8.3% by weight. The molar ratio Ca/Si of the C-S-H particles was 1.44.

General procedure for spray-drying of polymer dispersions

A) Preparation of the spray-dying feed:

For making the dispersions to be spray-dried the respective aqueous polymer dispersion was mixed with the respective aqueous solution of the spray-drying aid while stirring. The type and amounts of the polymer dispersion and the respective spray-drying aid used are shown in Table 1 . Additional water was used to adjust the concentration of the dispersion to be dried to 44 wt.-% relating to the solids content in the spray feed.

In case of co-spray-drying with a C-S-H-suspension, before the dilution step, 1-2 wt.-% (related on the latex content) C-S-H and 0.357-0.714 wt.-% (related on the latex content) calcium amidosulfonate were added to the dispersion.

B) Spray drying of the dispersion:

Spray-drying was conducted by means of a commercially available, laboratory-scale spray dryer (Niro Atomizer from Niro) using nitrogen as drying gas. The aqueous dispersion to be dried was sprayed through a two-fluid nozzle. The inlet temperature of the dryer gas was 130 to 140°C; its outlet temperature was 60 to 70°C. A first antiblocking agent (1 % by weight of hydrophobic silica powder, based on the total of all components of the final product) was fed into the drying chamber through an additional nozzle.

After removing the obtained powder from the spray dryer, it was mixed with 5-11 % by weight (based on the total of all components of the final product) of a second antiblocking agent, which were selected from commercially available anti-blocking agents, namely talc, limestone powder, or kaolin.

Determination of the re-dispersibility of the RDP:

The composition composed of a dispersion with spray-drying aid (SDA) specified in Table 1 was used to produce films and their re-dispersion was tested. For this purpose, the liquid dispersion (5 g of solids) in 10-15 mL of water was admixed with the described amount of the respective SDA and dried at room temperature for two days. About 0.5 g of the film was taken up in 10 mL of distilled water while stirring (200 rpm) at room temperature. On rapid re-dispersion within a few minutes, it was found that these dispersion systems also have excellent spray-dry ability and a re-dispersible powder (RDP) is obtained. Redispersion was assessed as follows:

• Complete redispersion within a few minutes: very good

• Virtually complete redispersion within a few minutes: good

• Incomplete redispersion (parts of the film still apparent): moderate

• Large parts of the film insoluble or no redispersion: poor

Table 1: Re-dispersibility of the different combinations of polymer dispersions and SDA as film and as RDP (reference examples).

* s.c. = solids content

** n.d. = not determined *** The percentages relate to additional polyvinyl alcohol, which was added before the spray-drying. The proportion of polyvinyl alcohol that was already present during the emulsion polymerization is not listed and also the saponification degree is unknown.

As it can be seen from the Table 1 , the polymer dispersions PD1 and PD2 based on a vinyl acetate-ethylene copolymer yielded re-dispersible films i powders in combination with polyvinyl alcohol (PVOH) as SDA (samples: combination 1 , combination 4, RDP1 , and RDP2). Contrary, the combination of the polymer dispersion PD3 based on a sty- rene-acrylate polymer with polyvinyl alcohol (PVOH) as SDA was not suitable and neither re-dispersible films nor re-dispersible dispersion powders were obtained.

Re-dispersible dispersion powders (Reference Examples)

Powder RDP-1

The re-dispersible dispersion powder (RDP-1) was a commercially polymer powder based on a copolymer of vinyl acetate and ethylene (VAE) and stabilized by polyvinyl alcohol as protective colloid. The copolymer has a minimum film forming temperature (MFFT) of about 0°C and a glass transition temperature of -5°C. The latex content of the powder is about 75% by weight, the remainder being essentially about 10-12 wt.-% of polyvinyl alcohol, 4-5 wt.-% kaolin and 9-11 wt.-% of limestone. An example is the polymer powder ETONIS® 3500 ED from Wacker.

Powder RDP-2:

The re-dispersible dispersion powder (RDP-2) is a commercially polymer powder based on a terpolymer of vinyl acetate, ethylene, and vinyl ester. The polymer has a minimum film forming temperature (MFFT) of ~ 0°C, a glass transition temperature of below 0°C and is stabilized by polyvinyl alcohol as protective colloid. The latex content of the powder is ~ 81% by weight the remainder being essentially about 10 wt.-% of polyvinyl alcohol 8-9 wt.-% kaolin. An example is the polymer powder VINNAPAS® 7055 E from Wacker.

Powder RDP-3

The polymer dispersion PD-3 was spray-dried according to the general procedure with 7 wt.-% spray-drying aid SDA-2 (based on the latex amount) as described above. The latex content of the powder is about 84% by weight.

Powder RD P-4

The polymer dispersion PD-3 was spray-dried according to the general procedure with 10 wt.-% spray-drying aid SDA-3 (based on the latex amount) as described above. The latex content of the powder is about 82% by weight.

Co-spray-drying of dispersions with C-S-H suspensions (according to the invention)

Combi-powder 1

The polymer dispersion PD-1 was mixed with 10 wt.-% spray-drying aid SDA-1 (PVOH), 1 wt.-% C-S-H-1 , and 0.357 wt.-% calcium amidosulfonate. All percentages relate on the latex content. The resulting suspension was diluted to 44 wt.-% relating to the solids content in the spray feed and was then spray-dried. Then, the resulting powder was mixed with 10 wt.-% of kaolin, based on the initially obtained powder, as antiblocking agent. The latex content of the powder was about 81 % by weight.

Combi-powder 2

The polymer dispersion PD-1 was mixed with 10 wt.-% spray-drying aid SDA-1 (PVOH), 2 wt.-% C-S-H1 , and 0.714 wt.-% calcium amidosulfonate. All percentages relate on the latex content. The resulting suspension was diluted to 44 wt.-% relating to the solids content in the spray feed and then spray-dried. Then, the resulting powder was mixed with 10 wt.-% of kaolin, based on the initially obtained powder, as antiblocking agent. The latex content of the powder was about 80% by weight.

Combi-powder 3 (not according to the invention)

The polymer dispersion PD-3 was mixed with 7 wt.-% spray-drying aid SDA-2 (polyacid), 1 wt.-% C-S-H1 , and 0.357 wt.-% calcium amidosulfonate. All percentages relate on the latex content. The resulting suspension was diluted to 44 wt.-% relating to the solids content in the spray feed and then spray-dried. Then, the resulting powder was mixed with 10 wt.-% of kaolin, based on the initially obtained powder, as anti-blocking agent. The latex content of the powder was about 83% by weight.

Unfortunately, the acid polymer dissolved the C-S-H nanoparticle suspension which caused a gel formation before spray-drying. The resulting powder was not re-dispersi- ble and could not be used for application within a waterproofing membrane.

Combi-powder 4 (not according to the invention)

The polymer dispersion PD-3 was mixed with 7 wt.-% spray-drying aid SDA-2 (polyacid)), 2 wt.-% C-S-H 1 , and 0.714 wt.-% calcium amidosulfonate. All percentages relate on the latex content. The resulting suspension was diluted to 44 wt.-% relating to the solids content in the spray feed and then spray-dried. Then, the resulting powder was mixed with 10 wt.-% of kaolin, based on the initially obtained powder, as antiblocking agent. The latex content of the powder was about 82% by weight.

The resulting powder was not re-dispersible and cannot be used for application within a waterproofing membrane.

Combi-powder 5 (not according to the invention)

The polymer dispersion PD-3 was mixed with 10 wt.-% spray-drying aid SDA-3 (a polymeric phenol sulfonic acid-formaldehyde condensate), 2 wt.-% C-S-H 1 , and 0.714 wt.- % calcium amidosulfonate (all percentages relate on the latex content). The resulting suspension was diluted to 44 wt.-% relating to the solids content in the spray feed and then spray-dried. Then, the resulting powder was mixed with 10 wt.-% of kaolin, based on the initially obtained powder, as anti-blocking agent. The latex content of the powder was about 80% by weight.

Application Tests

The influence of calcium-silicate-hydrate (C-S-H) nanocrystals in suspension or as powders on the hardening and drying of waterproofing membranes was investigated. Therefore, a dry powder was produced by mixing the ingredients according to Table 2.

Table 2: Building material composition (dry compound).

Application Examples:

700 g of the dry powder described in table 2 were mixed with the corresponding amount of the polymer dispersion or the RDP, respectively, as given in table 3 and water such that the resulting dispersion-modified slurry had a polymer dispersion I cement ratio (p/c) of 1 .087 and a water I cement ratio (w/c) of 1 .087. If the mixture was accelerated by C-S-H, the accelerator was also present during mixing in the following quantities: 1% or 2% solids content C-S-H (based on the latex solids content).

The addition of the hardening accelerator accelerates the hardening (defined in H. F. W. Taylor (1997): Cement Chemistry, 2nd edition, p. 212ft). The acceleration of the hydration is reflected by an increase of heat released by the hydration process compared to a normal sample without accelerator. For monitoring the acceleration of the hardening the cumulated heat of hydration released by the hydration process compared to a normal sample without accelerator was determined. Cumulated heat is given in joules per gram of cement that is released in an interval of 30 minutes to 5 hours or in an interval of 30 minutes to 10 hours after start of hydration (addition of water). For this, the slurry was filled in a PP beaker and placed in a calorimeter under isothermic conditions at a temperature of 20°C.

The references represent the heat flow without adding an additive according to the in- vention. The results are summarized in table 3:

Table 3: Cumulated heat of hydration of the dispersion-modified slurries mixtures with and without the C-S-H accelerators

1 ) % accelerator solids based on the polymer P solids content 2) accelerator was included in the spray-drying process (co-spray-drying)

As it can be seen from table 3, the acceleration of the cement hydration is stronger for polymer powders based on vinylacetate-ethylene copolymers as indicated by a higher cumulated heat of hydration (see examples 1-12) than for powders based on styreneacrylate copolymers (see comparative examples C1-C12). For the mixture of styrene acrylate RDP and C-S-H nanocrystals in suspension or as powdered form, the cement hydration cannot be accelerated appreciably.

For the co-spray-drying of C-S-H with polymer dispersion and SDA, the acceleration of the cement hydration is stronger for dispersions based on vinylacetate-ethylene copolymers as indicated by a higher cumulated heat of hydration (see examples 13 and 14). For the co-spray-drying of C-S-H with styrene acrylate RDP and SDA, the resulting combi-powders were not re-dispersible, or the cement hydration cannot be accelerated appreciably (see comparative examples C13, C14, and C15).

The dispersion-modified mineral building material mixture was used to produce a wet thin film (height: 1 .25 mm, width 12.0 cm, and length 20 to 25 cm) on a Teflon foil. The appearance of the dried building material was examined. All films, with the exception of those which were not re-dispersible (comparative examples C13 and C14), were homogeneous (no separation), mostly smooth, and had no cracks.

Furthermore, the water uptake of the dried film was evaluated by placing a part of the film (width: 8.5 cm x length: 18 cm) into a lockable plastic box with 100 g water. The water was changed every week. After three weeks, the film was dabbed with a paper towel and the weight was measured and divided by the initial weight. The percentage of weight gain due to water uptake was collected. The results are summarized in Table 4.

) Comparative examples ) Weight gain due to water uptake after water storage

Claims

1 . The use of a combination of: a) an organic polymer P as a component A in the form of an aqueous polymer dispersion or in the form of a polymer powder, where the organic polymer P is a vinylacetate-ethylene copolymer, where the organic polymer P has a glass transition temperature Tg of at most +10°C, in particular in the range of -30 to +5°C, especially in the range of -20 to +0°C, as determined by the differential scanning calorimetry (DSC) method according to ISO 11357- 2:2013, and b) a component B comprising particles of a calcium silicate hydrate containing calcium and silicon in a molar ratio Ca/Si of 0.1 to 2.2; in compositions for producing mineral waterproofing membranes which comprise at least one mineral binder.

2. The use of claim 1 wherein the weight ratio of the organic polymer P to the amount of calcium silicate hydrate in component B is in the range of 800:1 to 10:1.

3. The use of any one of the preceding claims wherein the combination is in the form of a powder composition containing the components A and B.

4. The use of claim 3 wherein the powder composition is obtained by joint spraydrying of an aqueous polymer dispersion of the organic polymer P and an aqueous suspension of the component B.

5. The composition of any one of the preceding claims, where the calcium silicate hydrate is of the following empirical formula a CaO- SiO₂ b AI₂O₃ c H₂O d X₂O e WO where

X is an alkali metal,

W is an alkaline earth metal different from Ca, a represents the molar proportion of CaO and is in the range of 0.5 to 2.0, b represents the molar proportion of AI₂O₃ and is in the range of 0 to 1 , c represents the molar proportion of hydration water H₂O and is in the range of 1 to 6, d represents the molar proportion of X₂O and is in the range of 0 to 1 , e represents the molar proportion of WO and is in the range of 0 to 1 , The composition of any one of the preceding claims, where the component B further comprises a polymer dispersant comprising structural units having anionic or anionogenic groups and structural units having polyether side chains, where the dispersant in particular comprises at least one polymer obtained by polymerizing at least one monomer having at least one anionic or anionogenic group and at least one monomer comprising at least one polyether side chain. The use of any one of the preceding claims wherein the combination further comprises a polyvinyl alcohol. The use of any one of the preceding claims wherein the combination does not comprise more than 2% by weight, based on the weight of the organic polymer P, of water-soluble polymers having carboxylic acid groups and/or sulfonic acid groups. The use of any one of the preceding claims wherein the combination is used in such an amount that the organic polymer P is present in the composition for producing the waterproofing membrane in amount in the range of 15 to 40% by weight, based on the total weight of dry matter of the composition for producing the waterproofing membrane and calculated as polymer P. The use of any one of the preceding claims wherein the combination is used in such an amount that the organic polymer P is present in the composition for producing the waterproofing membrane in amount such that the weight ratio of the polymer P to the mineral binder is in the range of 1 :3 to 2.0:1 . The use of any one of the preceding claims wherein the mineral binder in the composition for producing the waterproofing membrane comprises a cement of the cement group CEM I according to EN 197, in particular a cement classified as CEM I 42.5(R) or CEM I 52.5(R) or a mixture thereof. A composition for producing a mineral waterproofing membrane which comprises a combination of the components A and B as defined in any one of claims 1 to 10, and a powdery composition C comprising c.1 at least one mineral binder, in particular a cement of the cement group CEM I according to EN 197, more particularly a cement classified as CEM I 42.5(R) or CEM I 52.5(R) or a mixture thereof; and c.2 at least one powdery filler. A method for producing a mineral waterproofing membrane which comprises incorporating a combination of the components A and B as defined in any one of claims 1 to 10 and water into a powdery composition C comprising c.1 at least one mineral binder, where the mineral binder in particular comprises a cement of the cement group CEM I according to EN 197, more particularly a cement classified as CEM I 42.5(R) or CEM I 52.5(R) or a mixture thereof; and c.2 at least one powdery filler; to obtain a slurry and applying the slurry to a surface, where a water-tight covering is required. The composition or method of any one of claims 12 or 13 wherein the amount of the mineral binder is in the range of 10 to 40% by weight, based on the total weight of the dry matter of the composition used for producing the mineral waterproofing membrane. The composition or method of any one of claims 12 to 14 wherein the relative amount of the organic polymer P in the composition for producing the mineral waterproofing membrane is in the range of 15 to 40% by weight, based on the total weight of solid components of the mineral water-tight covering and calculated as polymer. The composition of any one of claims 12, 14 or 15 wherein the composition for producing the mineral waterproofing membrane is formulated

(i) as a two kits of part formulation comprising a first powdery composition containing the component A and the component B as a first part of the formulation and the powder composition C as a separately formulated second part of the formulation;

(ii) as a two kits of part formulation comprising a first liquid formulation part, which comprises the polymer dispersion of the polymer P and the component B and the powder composition C as a separately formulated second part of the formulation;

(iii) as a two kits of part formulation comprising the component A as an aqueous polymer dispersion or as a powder as a first part of the formulation and a powdery composition containing the constituents of composition C and the component B as a separately formulated second part of the formulation; (iv) as a two kits of part formulation comprising the component B as an aqueous suspension as a first part of the formulation and a powdery composition containing the constituents of composition C and the component A as a separately formulated second part of the formulation; or

(v) as a 1 K powdery formulation which is a mixture of the powdery components A and B and the powdery composition C. A powdery composition consisting of a) an organic polymer P as a component A in the form of an aqueous polymer dispersion or in the form of a polymer powder, where the organic polymer P is a vinylacetate-ethylene copolymer, where the organic polymer has a glass transition temperature Tg of at most +10°C, in particular in the range of -30 to +5°C, especially in the range of -20 to +0°C, as determined by the differential scanning calorimetry (DSC) method according to ISO 11357- 2:2013, b) a component B comprising particles of a calcium silicate hydrate containing calcium and silicon in a molar ratio Ca/Si of 0.1 to 2.2; and d) up to 30% by weight of further ingredients, based on the total weight of the composition; wherein the weight ratio of the organic polymer P of component A to the amount of calcium silicate hydrate in component B is in the range of 800:1 to 10:1. The powdery composition of claim 17 which is characterized by at least one of the following features (a) to (e) or any combination of said features (a) to (f):

(a) the powder composition is obtained by joint spray drying of an aqueous polymer dispersion of the polymer of component A and an aqueous suspension of the component B and optionally further ingredients;

(b) the powdery composition further comprises a water-soluble polymer having a plurality of hydroxyl groups, in particular polyvinyl alcohol;

(c) the powdery composition does not comprise more than 2% by weight, based on the weight of the component A, of water-soluble polymers having carboxylic acid groups and/or sulfonic acid groups;

(d) the powdery composition further comprises at least one organic compound OC, which is selected from monosaccharides, fruit acids and salts thereof, such as glucose, galactose, citric acid, gluconic acid or tartaric acid or salts thereof;

(e) the powdery composition further comprises at least one of a sulfonic acid, in particular a salt of amidosulfonic acid; (f) the weight ratio of the organic polymer P of component A to the amount of calcium silicate hydrate in component B is in the range of 200:1 to 10:1 , in particular in the range of 150:1 to 20:1 or in the range of 100:1 to 30:1.