MXPA99008151A - Method for producing semi-rigid compact or cellular shaped bodies with a pur base and the stabilization thereof;shaped bodies produced according to said method and the use thereof - Google Patents

Abstract

The invention relates to a method for producing polyester-polyurethane masses and the stabilization of said masses against hydrolytic ageing phenomena by means of a combination of agents consisting of compounds containing carboddimide with lactone derivatives. The invention also relates to shaped bodies produced from said masses and the use thereof for semi-rigid, compact and/or cellular shaped bodies.

Description

PROCEDURE FOR THE MANUFACTURE OF MOLDED BODIES COMPACT OR CELLULAR, SEMI-RIGID, BASED ON PUR AND ITS STABILIZATION, MOLDED BODIES MANUFACTURED WITH HIM AS WELL AS USE.

The invention relates to a process for the manufacture of polyester-polyurethane compositions as well as to their stabilization against phenomena of hydrolytic aging by means of a combination of active substances from compounds containing carbodiimide with lactone derivatives, to the bodies moldings made with it, as well as its use for compact and / or cellular semirigid molded parts.

Frequently, semi-rigid elastic polyurethane pieces are manufactured, in compact or cellular execution, that is, with light sponge, on the basis of polyester-polyurethane compositions. To improve the resistance of these materials in a humid environment, that is, under conditions of hydrolytic action, the addition of carbodiimides (Kunststoff Handbuch, volume VII, Polyurethane 1994 of DR G. Oertel, Cari-Hanser) has been proven for a long time. - Verlag, München), but in what other classes of substances also show activity REF .: 031119 for example 2-phenyliminoxazolidine or hydroxyethyl urea (FR-PS 1 450 919, US-PS 20 3 795 638).

However, this incorporation into the carbodiimide material is unsatisfactory when preparing relatively soft molded bodies of a hardness < 90 Shore A, and that they are also constructed in a chemically very linear manner and contain possibly high activator or catalyst contents for the acceleration of the PUR formation reaction. In this case, the elevation of a carbodiimide fraction, even above the generally usual and recommended content of about 2% by weight in the polyurethane mass, no longer leads to a persistent stability of the molded part against hydrolytic attack .

It has now been found that the stabilizing effect of the carbodiimides in the case of the simultaneous presence of lactones can be significantly increased. As the lactones used show no effect in the absence of carbodiimides, a combination effect appears. Furthermore, it is surprising that the combination of active substances found acts more stabilizingly than with a single carbodiimide content, even at several times the content.

The object of the invention is therefore a process for the manufacture of molded parts of foamed PUR, compact, transparent, as well as cellular according to the process of polyaddition of polyisocyanate, with a hardness of 40 to 90 Shore A by means of the reaction of a) organic and / or modified organic polyisocyanates b) at least one high molecular weight compound with at least two reactive hydrogens, as well as c) low molecular weight chain and / or cross-linking agents in the presence of d) catalysts and e) the mixture of carbodiimide and lactone active substances according to the invention as well as f) adjuvants and additives, characterized in that component e) is contained in the reaction composition with 0.50 to 20% by weight of a lactone or a mixture of lactones as well as 0.2 to 4.0% by weight of a carbodiimide or a mixture of carbodiimides.

Of the molded bodies manufactured according to the invention and their starting components a) to f), the following should be stated in detail: a) Polyisocyanates aliphatic, cycloaliphatic, araliphatic and preferably aromatic isocyanates come into question as organic polyisocyanates (a).

In particular, mention may be made, by way of example, of alkylene diisocyanates having 4 to 12 carbon atoms in the alkylene radical, such as 1,22-dodecan diisocyanate, 2-ethyl-tetramethylene diisocyanate-1,4,4-methyl-pentamethylene-diisocyanate-1,5, tetra-ethylene-diisocyanate-1,4, and preferably hexamethylene-diisocyanate-1, 6; cycloaliphatic diisocyanates, such as cyclohexane-1, 3-, and 1,4-diisocyanate, as well as the desired mixtures of these isomers, l-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate), 2,4 - and 2, 6-hexahydro toluylene diisocyanate as well as the corresponding mixtures of isomers, 4,4'-, 2,2'- and 2,4'-di-cyclohexylmethane diisocyanate, such as for example 1,4-xylylene diisocyanate and mixtures of isomers of xylylene diisocyanate and preferably di- and polyisocyanates, such as, for example, 2,4- and 2,6-toluylene diisocyanate and the corresponding mixtures of isomers; 1, 5-naphthylene diisocyanate (NDI), 4,4'-, 2,4'- and 2, 2'-diphenylmethane diisocyanate (MDI) and the corresponding mixtures of isomers, mixtures of 4,4'-and 2 , 4'-diphenylmethane-diisocyanates, polyphenyl-polymethylene-polyisocyanates, mixtures of 4,4'-2,4'- and 2, 2'-diphenylmethane-diisocyanates and polyphenyl-polymethylene-polyisocyanates (crude MDI) and mixtures of crude MDI and toluylene diisocyanates . The di- and polyisocyanates can be used separately or in the form of mixtures.

Often, so-called modified polyvalent isocyanates are also used, that is, products that are obtained by chemical conversion of organic di- and / or polyisocyanates. Mention may be made, by way of example, of the di- and / or polyisocyanates containing ester groups, urea, biuret, allophanate, carbodiimide, isocyanurate, uretdione, uretonimine and / or urethane. In particular, exemplary organic polyisocyanates, preferably aromatic, containing urethane groups, having an NCO content of 33.6 to 15% by weight, preferably 31 to 21% by weight, based on to the total weight, for example with diols, triols, dialkylene glycols, trialkylene glycols or polyoxyalkylene glycols of small molecule with molecular weights of up to 6000, 4,4'-diphenylmethane-diisocyanate modified, mixtures of 4,4'- and 2,4 '-diphenylmethane diisocyanates or 2,4'- or 2,6'-toluylene diisocyanate, mention may be made, by way of example, of di- or polyoxyalkylene glycols, which may be used separately or as mixtures: diethylene -, dipropylene-, polyoxyethylene-, polyoxypropylene- and polyoxypropylene-polyoxyethylene glycols. Also suitable are the prepolymers containing NCO groups with NCO contents of 25 to 3.5% by weight, preferably 23 to 13% by weight, based on the total weight, obtained from the polyether- and / or preferably polyester-polyols described below and 4,4'-diphenylmethane-diisocyanate, mixtures of 4,4'- and 2,4'-diphenylmethane diisocyanate or 2,4'- and / or 2,6'-toluylene- diisocyanates, as well as NDI or crude MDI. Liquid polyisocyanates containing carbodiimide groups and / or isocyanurate rings having an NCO content of from 33.6 to 15% by weight, preferably from 31 to 21% by weight, based on total weight, for example based on in 4,4'-, 2,4'- and / or 2, 2'-diphenylmethane diisocyanate and / or 2,4'- and / or 2,6'-toluylene diisocyanate.

The modified polyisocyanates can be mixed, if appropriate, with one another or with unmodified organic polyisocyanates, such as, for example, 2,4'-, 4,4'-diphenylmethane diisocyanate, crude MDI and / or 2,6'-toluylene. -diisocyanate. For example, mixtures of diphenylmethane diisocyanates and / or toluene diisocyanates and / or crude MDI modified with urethane groups and, if appropriate, diphenylmethane diisocyanates and / or toluene diisocyanates and / or unmodified crude MDI are suitable.

The organic polyisocyanates have been especially suitable and are thus preferably used for the production of the polyurethane moldings according to the invention: Polyisocyanates with aromatically bound isocyanate groups of an average NCO functionality of 2 to 3. Especially isocyanates preferred are polyisocyanates or mixtures of liquid polyisocyanates at ambient temperature, of the diphenylmethane series, that is, liquid mixtures at room temperature of 4,4 '-diphenylmethane-diisacyanate with 2,4'-diphenylmethane diisocyanates, liquid derivatives at room temperature environment of these isocyanates modified with carbodiimide or with uretonimine and reaction products of these isocyanates with liquid polyols at room temperature. These semi-pre-polymers are transformation products with an NCO / OH equivalent ratio of 2.2: 1 to 20: 1. " Suitable high molecular weight polyhydroxy compounds (b) are those having a functionality of 2 to 8 and an average molecular weight of 400 to 12 000. Polyols selected from the group of polyethers are especially suitable. - polyols, polyester polyols, polythioether polyols, polyesteramides containing hydroxyl groups, polyacetals containing hydroxyl groups, aliphatic polycarbonates containing hydroxyl groups and polymodified polyether polyols or mixtures of at least two of the polyols mentioned. Polyester polyols and / or polyether polyols find application in particular.

Suitable polyester-polyols can be obtained, for example, from organic dicarboxylic acids having 2 to 12 carbon atoms, preferably aliphatic dicarboxylic acids having 4 to 6 carbon atoms and polyvalent alcohols, preferably diols, with 2 to 12 carbon atoms, preferably 2; to 6 carbon atoms. The dicarboxylic acids contemplated by way of example are: succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decandicarboxylic acid, maleic acid, fumaric acid, phthalic acid, iso-phthalic acid and terephthalic acid. The dicarboxylic acids can be used in this case both separately and also in mixtures with one another. Instead of the free dicarboxylic acids, it is also possible to use the corresponding dicarboxylic acid derivatives, such as, for example, the mono- or di-esters of dicarboxylic acids with alcohols having 1 to 4 carbon atoms or anhydrides of dicarboxylic acids. Preference is given to using dicarboxylic acid mixtures of succinic, glutaric and adipic acid in quantities of, for example, 20 to 35:35 to 50:20, up to 32 parts by weight, and especially adipic acid. Examples of divalent and polyvalent alcohols, in particular diols and alkylene glycols, are: ethanediol, diethylene glycol, 1,2- or 1,3-propanediol, dipropylene glycol, methyl-1,3-propanediol, 1,4-butanediol, 1,5 -pentanediol, 1,6-hexanediol, neopentyl-glycol, 1, 10 -decanodol, glycerin, trimethylolpropane and pentaerythritol. Preference is given to using: ethanediol, diethylene glycol, 1-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane or mixtures of at least two of the diols mentioned, in particular mixtures of ethanediol, 1,5-butanediol, 1,6- hexanediol, glycerin and / or trimethylolpropane. Polyester-polyols can also be used from lactones, for example e-caprolactone or hydroxycarboxylic acids, for example γ-hydroxycaproic acid.

For the production of polyester polyols, the polycarboxylic acids and / or polyvalent alcohols and derivatives, for example aromatic and preferably aliphatic, can be polycondensed in the absence of catalysts or, preferably, in the presence of esterification catalysts, conveniently an atmosphere of inert gases, such as nitrogen, carbon monoxide, helium, argon, among others, in a melt at temperatures of 150 ° C to 200 ° C, preferably 180 to 220 ° C. if the case were at reduced pressure to the desired acid number, which is advantageously less than 10, preferably lower than 1.

According to a preferred embodiment, the esterification mixture is polycondensed at the temperatures mentioned above up to an acid number of 80 to 30, preferably 40 to 30, under normal pressure and then at a pressure of less than 500 mbar, preferably from 50 to 150 mbar. Suitable catalysts for the esterification are, for example, catalysts of iron, cadmium, cobalt, lead, zinc, antimony, magnesium, titanium and tin, in the form of metals, metal oxides or metal salts. However, the polycondensation can also be carried out in the liquid phase in the presence of diluents or entrainers, such as, for example, benzene, toluene, xylene or chlorobenzene, for the azeotropic distillation of the condensation water.

For the production of the polyester polyols, the polycarboxylic organic acids and / or their polyvalent alcohols and derivatives are polycondensed, preferably in a molar ratio of 1: 1 to 1.8, preferably 1: 1.05 to 1.2.

The polyester polyols obtained preferably have a functionality of 2 to 3, in particular 2 to 2.6, and an average molecular weight of 600 to 6,000, preferably 1,000 to 4,000.

Suitable polyether polyols are those which are obtained according to known processes, for example by means of anionic polymerization with alkali hydroxides, such as sodium or potassium hydroxide, or alkali alcoholates, such as sodium methylate, sodium or potassium ethylate or potassium propylate, as catalysts and under the addition of at least one initiation molecule, containing from 2 to 8, preferably 2 or 3, reactive hydrogen atoms attached, or by cationic polymerization with Lewis acids, such as antimony pentachloride, boron fluoride etherate among others or smectite clay as catalysts from one or more alkylene oxides with 2 to 4 carbon atoms in the alkylene moiety.

Suitable alkylene oxides are, for example, tetrahydrofuran, 1,3-propylene oxide, 1,2- or 2,3-butylene oxide, styrene oxide and preferably ethylene oxide and 1,2-propylene oxide. The alkylene oxides can be used separately, alternatingly one after the other or as mixtures. Suitable initiating molecules include, for example, water, organic dicarboxylic acids, such as succinic acid, adipic acid, phthalic acid and terephthalic acid, N-mono-, N, N- and N, N'-dialkyl substituted, aliphatic diamines. and aromatic, with 1 to 4 carbon atoms in the rest of. alkyl, as, if necessary, ethylenediamine, 1,3-propylenediamine, 1,3- or 1,4-butylenediamine, 1,2-, 1,3-, 1,4-, 1,5- and 1 , 6-hexamethylenediamine, phenylenediamine, 2,3-, 2,4-, and 2,6-toluylenediamine and 4,4'-, 2,4'- and 2, 2'-diamino-diphenylmethane, mono- and dialkyl- replaced. Suitable starter molecules are: alkanolamines, for example ethanolamine, N-alkyl-alkanolamines, for example N-methyl- and N-ethyl-ethanolamine, dialkanolanes, such as diethanolamine, N-alkyl dialkanolamines, for example N -methyl- and N-ethyl-diethanolamine and trialkanolamines, such as for example triethanolamine and ammonia. Preference is given to using polyhydric alcohols, in particular divalent and / or trivalent alcohols and / or dialkylene glycols, such as ethanediol, 1,2- and 1,3-propanediol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol. , glycerin, trimethylolpropane, pentaerythritol, sorbitol or sucrose or mixtures of at least two polyvalent alcohols and, if appropriate, additional water.

The polyether polyols, preferably polyoxypropylene and polyoxypropylene polyoxyethylene polyols, advantageously have a functionality of 2 to 8, average molecular weights of 800 to 12 000, preferably of 1 000 to 6 000, and conveniently a content of alkali ions of less than 10 ppm. Polyether polyols modified by polymers are also suitable as polyether polyols, preferably graft polyether polyols, especially those based on styrene or acrylonitrile which are obtained by in situ polymerization of acrylonitrile, styrene or preferably mixtures of styrene and acrylonitrile, for example in a weight ratio of 90:10 to 10:90, preferably 70:30 to 30:70, in a manner convenient to the polyether polyols mentioned above analogously to the data of the German patents 11 11. 394, 12 22 669 (US 3 304 273, 3 383 351, 3 523 093), 11 52 536 (GB 10 40 452) and 11 52 537 (GB 987 617), as well as polyether-polyol dispersions, which contain as a dispersed phase, usually in an amount of from 1 to 50% by weight, preferably from 2 to 25% by weight: for example inorganic fillers, polyureas, polyhydrazides, polyurethanes containing tere-amino-linked groups and / or melamines and which are described for example in EP-A-0 1 1 752 (CA 1 166 403), EP-B-01 1 752 (US 4 304708), US-A-4 374 209 and DE-A 32 31 497 .

The polyether polyols can be used, in the same way as polyester polyols, separately or in the form of mixtures. They can also be mixed with the polymer modified polyether polyols or polyester polyols as well as with the polyesteramides, polyacetals and / or polycarbonates containing hydroxyl groups.

Suitable polyacetals containing hydroxyl groups are, for example, compounds which can be prepared from glycols, such as diethylene glycol, triethylene glycol, 4,4'-dihydroethoxy-diphenyl-dimethyl-methane, hexanediol and formaldehyde. Also by means of polymerization of cyclic acetals suitable polyacetals can be obtained.

Suitable polycarbonates which show hydroxyl groups are those of the known art which can be obtained by the reaction of diols such as 1,3-propanediol, 1,4-butanediol and / or 1,6-hexanediol, diethylene glycol, trioxyethylene glycol or tetraoxyethylene glycol with diarylcarbonates, for example diphenylcarbonate or phosgene.

Among the polyesteramides containing hydroxyl groups are, for example, essentially linear condensates obtained from polyvalent, saturated and / or unsaturated carboxylic acids or their polyvalent, saturated and / or unsaturated anhydrides and amino alcohols or mixtures of alcohols and aminoalcohols and / or polyamines .

The molded bodies based on polyurethane can be manufactured without or with the joint application of chain extension and / or crosslinking agents (c). However, for the modification of the mechanical properties, for example the hardness, the addition of chain extension agents, crosslinking agents or, if appropriate, also mixtures thereof can be proven to be advantageous. As chain-extending and / or cross-linking agents, for example, small-molecule polyhydric alcohols, preferably diols and / or triols, with average molecular weights of less than 480, preferably from 60 to 300, are used. for example, water, aliphatic, cycloaliphatic and / or araliphatic diols with 2 to 14, preferably 2 to 6 carbon atoms, such as for example propanediol-1,3, methyl-propanediol-1,3, decanediol-1, 10, o-, m-, p-dihydroxy-cyclohexane, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, bis- (2-hydroxyethyl) -bisphenol A and bis- (2-hydroxyethyl) -hydroquinone and preferably ethanediol, butanediol-1 , 4, hexanediol-1, 6, triols, such as 1,2,4-, 1,3,5-trihydroxy-cyclohexane, trimethylol-ethane, glycerin, trimethyl-propane and triethanolamine as well as alkylene polyoxides containing hydroxyl groups, for example with average molecular weights of up to 2 500, preferably from 130 to 850, bases two in ethylene oxide and / or 1, 2-propylene and the starter molecules mentioned above with respect to obtaining the polyester-polyole.

Suitable chain extension agents are also N, N'-dialkyl-substituted aromatic diamines which, if appropriate, can also be substituted in the aromatic radical by means of alkyl groups with 1 to 20, preferably 1 to 4. carbon atoms in the N-alkyl moiety, such as, for example, N, N'-diethyl, N, N'-di-sec-pentyl, N, N '-de-sec-hexyl-, N, N'-di -sec-decyl- and N, N '-dicyclohexyl-, p- or m-phenylenediamine, N, N'-dimethyl-, N, N'-diethyl-, N, N'-diisopropyl-, N, N'- di-sec-butyl-, and N, N '-dicyclohexyl-4,4'-diamino-diphenylmethane and N, N' -di-sec-butylbenzine.

As long as the compounds of the components (c) are used together, they can be used in the form of mixtures or separately, advantageously in amounts of 1 to 20 parts by weight, preferably 1.5 to 14 parts by weight, referred to 100 parts by weight of the high molecular weight compound (b).

As catalysts (d) for the manufacture of compact or cellular semirigid molded bodies, compounds which accelerate strongly the reaction of the compounds containing hydroxyl groups of component (b) and, if appropriate (c) with the organic polyisocyanates (a), if the case were modified. Strongly basic amines are considered. Mention is made, by way of example, of amidines, such as 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine, diazobicycloundecane, tertiary amines, such as triethylamine, tributylamine, dimethylbenzylamine, N-methyl, N-ethylmorpholine, N, N, N ', N'-tetramethylethylenediamine, pentamethyl diethylenetriamine, tetramethyl diaminoethyl ether, bis- (dimethylaminopropyl) urea, dimethylpiperazine, 1,2-dimethylimidazole, 1-aza-bicyclo- (3, 3, 0) -octane, especially also compounds of alkanolamine, such as triethanolamine, triisopropylamine, .N-methyl-, N-ethyldiethanolamine and preferably 1,4-diazabicyclo- (2, 2, 2) -octane and their mixtures with the aforementioned basic amines.

Also suitable are organometallic compounds, preferably organic tin compounds, such as tin (II) salts of organic carboxylic acids and dialkyltin salts (IV) of organic carboxylic acids. The organometallic compounds are used alone or preferably in combination with the strongly basic amines mentioned above.

The manufacture of the molded bodies uses a mixture of a carbodiimide or carbodiimides and a lactone or lactone derivatives, as a stabilizing aid that significantly delays the aging phenomena of the molded body of PUR, caused by hydrolysis.

The carbodiimide of diisopropylphenylisocyanate (STABAXOL 1 ® from Rheinchemie) has proved particularly suitable, but also other carbodiimides as reaction products of monofunctional isocyanates as well as carbodiimide polymers as reaction products of di- and multifunctional isocyanates show the properties according to the invention.

Suitable lactone derivatives are y-valerolactone, d-decalactone and d-dodecalactone, especially e-caprolactone and especially y-butyrolactone, as well as mixtures of the aforementioned lactones. The fractions of the mixture according to the invention in the reaction composition of the PUR are from 0.5 to 20% by weight of the lactone components and from 0.8 to 10%. by weight of the carbodiimide components, preferably from 0.8 to 10% by weight of the lactone components and from 0.5 to 2.5% by weight of the carbodiimide components. f) For the production of the moldings according to the invention, adjuvants and additives (f) can also be used together if necessary.

Examples of adjuvants and additives which may be mentioned are blowing and expanding agents, surface-active substances, foam stabilizers, cell regulators, sliding agents, fillers, coloring substances, pigments, antistatics and substances with fungistatic effect. and bacteriostatic.

As an agent. of foaming and expansion, water is preferably used, which reacts with the organic polyisocyanates (a), modified if necessary, with the formation of carbon dioxide and urea groups. The water is usually used in application amounts of from 0.03 to 3% by weight, preferably from 0.05 to 1.5% by weight in the reaction composition of the PUR. As fluffing agents which can be used together, if appropriate, they can be used instead of or preferably in combination with water, also low-boiling liquids, which under the influence of the exothermic polyaddition reaction, are they evaporate and advantageously have a boiling point at normal pressure in the range from -40 to 100 ° C, preferably from 0 ° to 60 ° C or gases.

The liquids and gases of the type mentioned above, suitable as foaming agents can for example be selected from the group of alkanes, dialkyl ethers, dialkylene ethers, ketones, esters of carboxylic acids, fluoroalkanes, chlorofluoroalkanes as well as noble gases, nitrogen and carbon dioxide More detailed data on the other customary additives and adjuvants mentioned above can be taken from the literature, for example from Kunststoffhandbuch, Polyurethane, Volume VII, Cari-Hanser-Verlag, München, Vienna, Ia, 2a, and 3rd, edition 1966, 1983 and 1994.

For the preparation of the molded articles, polyisocyanates (a) organic, if appropriate modified, polyhydroxylated compounds (b) of high molecular weight and, where appropriate, chain extension agents and / or crosslinking agents ( c) of low molecular weight, in such quantities, that the ratio of equivalents of. the NCO groups of the polyisocyanates (a) with respect to the sum of the reactive hydrogen atoms of the rest of the components, is from 1: 0.3 to 1: 2, preferably from 1: 0.4 to 1: 1.7 and in particular from 1 : 0.9 to 1: 1.1.

The shaped bodies can be manufactured according to known methods, for example according to the prepolymer process, the semi-polymer process or the "one-shot" process with the aid of the high-pressure or preferably the low-pressure technique. The production of molded bodies is conveniently carried out in closed, temperable molds, for example, metal molds, for example made of aluminum, cast iron or steel, or molds of resins of polyester or epoxide, reinforced with fiber. Some formulations of low viscosity, good flowability and therefore, with improved processability properties, can also be processed with the aid of the injection molding and reaction technique (RIM technique) to form moldings.

These methods of procedure are described, for example, by Dr. H. Piechota and Dr. H. Rohr in "lntegralschaumstoffe", Cari-Hanser Verlag, München, Wien 1975; DJ Prepelka and JL Wharton in Journal of Cellular Plastics, March / April 1975, pages 87 to 98, U. Knipp in Journal of Cellular Plastics, March / April 1973, pages 76 to 84 and in Kunststotthandbuch, volume 7, Polyurethane, 2a, edition, 1983, pages 333 and following.

In the process according to the invention, components (a) to (f) are preferably reacted according to the "one-shot" method in closed molds. Here several reaction components are used, preferably 2 or 3, in which case the polyisocyanate components (a) generally form one, and the other starting components (b) to (f), one or more of the other components of the reaction.

Component (e) according to the invention can be metered, however, also separately or in combination with component (a) or (b) or (c) as well as (f), in the case that it is virtually anhydrous (< 0.05% in weight) It has proven to be particularly advantageous to work according to the two-component process and to combine the two components (b) to (f) in component (B) and to use the organic polyisocyanates, the modified polyisocyanates or the mixtures of the polyisocyanates mentioned, as component (A).

The starting components are mixed at a temperature of 15 to 100 ° C, preferably 25 to 55 ° C and are brought to the open or closed mold under normal pressure or at elevated pressure. The mixing can be carried out by mechanical means by means of an agitator or a stirring screw or at high pressure in the so-called countercurrent injection process. The temperature of the mold is conveniently from 10 to 140 ° C and preferably from 20 to 80 ° C.

After a dwell time of 0.5 to 10 minutes, preferably from 1 to 6 minutes, molded bodies are generally obtained which are sufficiently solidified, which are directly demoulded or which can then be directly coated with one or more PUR reaction compositions. more, so that molded pieces of multilayer PUR are obtained in many cases just by changing the mold cover.

The amount of the reaction mixture according to the invention, which is introduced into the mold, is advantageously dimensioned so that the molded bodies obtained based on polyurethane have a bulk density of 150 to 1 400 kg / m 3, with a hardness of 20. at 90 Shore A, but preferably from 200 to 700 kg / m3 with 30 to 80 Shore A as well as 900 to 1 250 kg / m3 with 50 to 80 Shore A.

Polyurethane plastics of this type represent particularly valuable starting materials for technical articles usually exposed to the weather and exposed to moisture, such as rollers or spring elements, or also shoe soles in a variant of execution in one or several layers.

Examples In the examples indicated, isocyanate-containing prepolymers of the following composition were used: 1) Prepolymer (Ai) 56. 5% by weight of 4,4'-MDI 6.5% by weight of 4,4'-MDI modified with carbodiimide 37.0% by weight of poly (ethylene-adipate butylene) 10H..55 The resulting NCO content is 19.3% 2) Prepolymer (A2) 56. 5% by weight of 4,4'- MDI 6.0% by weight of 4,4'-MDI modified with carbodiimide 37.4% by weight of block of polyoxypropyleneoxyethylene-copolyetherdiol 10H: 28 The resulting NCO content is 19.2%. 3) Prepolymer (A3) 56. 3% by weight of 4,4'- MDI 6.2% by weight of 4,4'-MDI modified with carbodiimide 23.6% by weight of poly (ethylene-butyl adipate) 10H: 55 13.9% by weight of polyoxypropylene-oxyethylene block - 10H copolyether diol: 28. The resulting NCO content is 19.0%.

The following materials are used as polyol components: 4) Polyester polyol (Bi) linear poly (ethylene adipate) 10H: 55 5) Polyester polyol (B2) linear poly (ethylene adipate) 10H: 37 6) Polyether polyol (B3) a linear polyoxypropylene oxyethylene-copolyether diol block 10H: 28 7) Polyether polyol (B ") a linear polyoxypropylene oxyethylene copolyether diol block initiated with trimethylol propane 10H: 35 Example 1 The prepolymer (Ai) is made with a mixture (Ci) consisting of: 91. 2% by weight of polio (BL) 1.5% by weight of Stabaxol I (Rheinchemie brand) 5.5% by weight of 1,4-butanediol and 1.8% by weight of diazabicyclooctane The temperatures of the materials are in each case 45 ° C, the mixing ratio of the components (Ci) to (Ai) is 100: 47.0 parts by weight. By means of the use of a low-pressure processing machine, for example a PSA 95 from the firm Klóckner Ferromatik Desma GmbH, compact PUR moldings are obtained, which have reacted in the range of 3 minutes with a density of 1 200 kg / m3 and a hardness of 68 Shore A. For the test of the resistance to aging by humidity, the tensile test according to DIN 53 504 i is measured. A. both before and after wet storage according to DIN 53 508 i. A., that is, 7 d at 70 ° C and 95% relative humidity. The tensile strength in this case decreases from 21.0 MPa to 3.0 MPa.

Example 2 The prepolymer (Ai) is prepared analogously to Example 1, with a mixture (C2) consisting of 86. 2% by weight of polyol (Bx) 1.5% by weight of Stabaxol 1 (Rheinchemie brand) 5.5% by weight of 1,4-butanediol and 5.0% by weight of y-butyrolactone 1.8% by weight of diazabicyclooctane The mixing ratio of the components (C a (Ai) is located at 100: 46.5. The mechanical test shows only a drop in tensile strength from 20.5 MPa to 12.8 MPa.

Example 3 The prepolymer (A2) is made with the mixture of polyols (Ci) of Example 1 at a mixing ratio of 100 parts of (Ci) to 48.4 parts of (A2). The tensile strength of the solid PUR drops after storage analogously to Example 1, from 12.7 MPa to 1.8 MPa.

Example 4 The prepolymer (A2) is made with the mixture of polyols (C2) of Example 1 at a mixing ratio of 100 parts of (C2) to 48.0 parts of (A2). The tensile strength of the solid PUR drops after storage analogously to Example 1, from 11.8 MPa to 6.8 MPa.

Example 5 The prepolymer (Ai) is made with a mixture (C3) consisting of 81. 0 I by weight of polyol (B3) 12.1% by weight of polyol (B4) 1.2% by weight of Stabaxol I 4.3% by weight of ethanediol 1.4% by weight of diazabicyclooctane The temperature of the materials is 40 ° C for the component (Ai), 30 ° C for the component (C) The mixing ratio of the components (C3) to (A :) is 100: 41 parts by weight .

The tensile strength of the resulting solid PUR is 12.4 MPa, after aging analogously to Example 1, of 3.2 MPa.

Example 6 The prepolymer (Ai) is prepared analogously to Example 5, with a mixture i d) consisting of 75. 5% by weight of polyo (B3) 12.1% by weight of polyol (B4) 1.2% by weight of Stabaxol I 4.3% by weight of ethanediol 1.4% by weight of diaza-bicyclooctane 5.5 by weight of y-butyrolactone The mixing ratio of (C4) to (? ± -) is 100: 40 loaves by weight. The tensile strength of the resulting solid PUR is 11.1 MPa, after aging analogously to Example 1, of 6.1 MPa.

Example 7 The prepolymer (A3) is made with a mixture (C5) consisting of 91. 50% by weight of polio (B;) 1.2% by weight of Stabaxol 1 5.75% by weight of 1,4-butanediol 0.35% by weight of ethanediol 1.10% by weight of diazabicyclooctane The temperature of the materials is 30 ° C for the component (A3), 30 ° C for the component (C5). The mixing ratio of (Cs) to (A3) is 100: 43.5. The tensile strength of the resulting solid PUR is 22. 4 MPa, after aging in a manner analogous to Example 1, of 4.1 MPa.

Example 8 The prepolymer (A3) is made with a mixture (Ce) consisting of 85.10% by weight of polyol (B2) 1.3% by weight of Stabaxol I 5.75% by weight of 1,4-butanediol 0.35% by weight of ethanediol 6.40% by weight of y-butyrolactone 1.10% by weight of diazabicyclooctane The temperature of the materials is 30 ° C for the component (A3), 55 ° C for the component (C). The mixing ratio of (Ce) to (A3) is 100: 43.0. The tensile strength of the resulting solid PUR is 21. 8 MPa, after aging analogously to Example 1, of 11.1 MPs.

Example 9 The prepolymer (Ai) is made with a mixture (Ci) consisting of 89. 00% by weight of polio (Bi) 8.65% by weight of ethanediol 0.35% by weight of water 1.2% by weight of Stabaxol 0.80% by weight of diazabicyclooctane The temperature of the materials is 40 ° C for the component (Ai), of 45 ° C for the component (C7). The mixing ratio of (C7) to (Ai) is 100: 86 parts by weight. The resulting PUR, with a free foam density of 310 kg / m3, is manufactured at densities of molded parts of 550 kg / m3. The tensile strength of the foamed PUR material is 8.2 MPa, after aging analogously to Example 1, of 6.1 MPa.

Example 10 The prepolymer (Ai) is prepared analogously to Example 9 with a mixture (Ca) consisting of 84. 30% by weight of polyol (Bi) 8.65% by weight of ethanediol 0.35% by weight of water 1.20% by weight of Stabaxol 4.70% by weight of y-butyrolactone 0.80% by weight of diazabicyclooctane The mixing ratio of (C8) to (Ai). is 100: 87 parts by weight. The resulting PUR, with a free foam density of 320 kg / m3, is manufactured at densities of molded parts of 550 kg / m3. The tensile strength of the foamed PUR material is 7.9 MPa, after aging analogously to Example 1, of 7.1 MPa.

It is noted that, in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is that which is clear from the manufacture of the objects to which it relates. Having described the invention as above, the content of the following is claimed as property.

Claims (6)

1. Process for the manufacture of semirigid, compact or cellular bodies based on polyurethane characterized by the reaction of a) organic and / or organic polyisocyanates modified with b) one or more polyhydroxyl compounds of high molecular weight c) chain extension agents and / or crosslinking, d) reaction accelerators or catalysts, e) a mixture of active substances from a carbodiimide derivative and a lactone derivative f) if appropriate, other adjuvants and additives, characterized because the component a) and / or b) contains a polyol ester component cleavable by hydrolysis, and because the addition of the combination of active substances e) to the reaction mixture is carried out, by the chosen lactone of 0.5 to 20.0% by weight, preferably from 0.2 to 10.0% by weight, and by the chosen derivative containing carbodiimide groups, from 0.2 to 4.0 I by weight, preferably from 0.5 to 2.5% by weight.

2. Polyurethane reaction compositions containing polyester groups as semirigid, compact or cellular molded bodies, manufactured according to claim 1, characterized in that for stabilization against the phenomena of hydrolytic aging, they contain a combination of active substances from a carbodiimide-containing compound and a lactone derivative. .

3. Molded bodies manufactured according to claim 1, characterized in that the carbodiimide diisopropyl-phenyl-isocyanate and -butyrolactone are used as the lactone as a combination of active substances.

4. Molded bodies manufactured according to claim 1, characterized in that the carbodiimide of diisopropyl-phenyl-isocyanate and e-caprolactone are used as the lactone as a combination of active substances.

5. Molded bodies manufactured according to claim 1, characterized in that their density is 150 to 1 400 kg / m3.

6. Use of the molded bodies based on polyurethane according to one of claims 2 to 5 as technical articles, which are usually exposed to the weather, and also as shoe material or shoe soles.