MXPA00009591A - Process for coating substrates having polar surfaces with polyurethane latexes - Google Patents

Abstract

Claimed is a substrate having a polar surface and, adherent thereto, a polyurethane polymer which was applied as a latex. The latexes of the present invention are chain extended in water with aminoethyl ethanolamine and are prepared and applied in the substantial absence of organic solvents. The prepolymers used to prepare the latexes are substantially free of ionic groups on the polymer backbone.

Description

PROCESS TO COVER SUBSTRATES THAT HAVE POLAR SURFACES WITH POLYURETHANE LATEX This invention relates to polyurethane latex, to processes for preparing them, to polymers prepared therewith, and to substrates coated therewith. This invention relates particularly to the coating of substrates having polar surfaces with polyurethane latex. It is known that latex polymers are useful in many applications such as paints, sealants, and films. Polyurethane latexes are less widely used due to the inherent difficulties in preparing stable aqueous polyurethane latexes. For example, the formulation components of the polyurethane, such as polusocyanates, can be reactive with water. The polyurethane prepollomers useful in forming the latexes are often liquids of no low viscosity at ambient conditions. These and other properties can cause the polyurethane latexes to be unstable, that is, to form a dispersion that is separated from the continuous aqueous phase of the latex, which is often not desirable in an industrial jurisdiction.

Recently, there have been many advances in the art to prepare stable polyurethane latex, free of organic solvents. For example, U.S. Patent Application Number 09/03 / 9,976, filed March 16, 1998, describes the preparation of those polyurethane latexes. U.S. Patent Application Number 09 / 039,978, filed March 16, 1998, describes the preparation of carpets using polyurethane latex. As these latex become more available and widely used, it will be desirable to improve their performance, particularly with respect to physical properties. It would be desirable in the art to coat substrates with polyurethane latex, be able to coat substrates having polar surfaces with a urethane poly latex having good adhesion thereto. It would be particularly desirable if the polyurethane latex having good adhesion on polar surfaces, were an aqueous polyurethane latex, free of organic solvents. In one aspect the present invention is an article of manufacture comprising a substrate having a polar surface and, adhered thereto, a polyurethane polymer prepared from a latex wherein: (A) the polyurethane latex is prepared at starting from a polyurethane prepolymer having a polymer base structure, substantially free of ionic groups, and prepared from a prepolymer formulation including polyols that they have an average content of ethylene oxide of less than 80 weight percent, (B) the prepolymer is chain extended with a chain extender of aminoethyl ethanolamine (AEEA), and (C) the prepolymer and latex are prepared in the substantial absence of an organic solvent. In another aspect, the present invention is a process for preparing a latex coated substrate, which comprises applying a polyurethane latex to a polar surface of a substrate having a polar surface wherein: (A) the polyurethane latex is prepared at starting from a polyurethane prepolymer having a base structure of the polymer, substantially free of ionic groups, and prepared from a prepolymer formulation including polyols having an average ethylene oxide content of less than 80 weight percent , (B) the prepolymer is chain extended with a chain extender of ammoethyl ethanolamine, and (C) the prepolymer and latex are prepared in Ta substantial absence of an organic solvent. In yet another aspect, the present invention is a polyurethane latex which can be used to prepare a polyurethane polymer having improved adhesion properties, comprising a polyurethane latex wherein: (A) the polyurethane latex is prepared from of a polyurethane prepolymer having a polymer base structure, substantially free of ionic groups, and prepared from of a prepolymer formulation including polyols having an average ethylene oxide content of less than 80 weight percent, (B) the prepolymer is chain extended with a chain extender of aminoethyl ethanolamine, and (C) Prepolymer and latex are prepared in the substantial absence of an organic solvent. To prepare the embodiments of the present invention, a polyurethane latex is formed. For the purposes of the present invention, the term "polyurethane" is defined to include compounds known in the art for preparing polymers, but for clarity, these terms are defined as follows. A "polyurethane" is a polymer that has a structure similar to that of a polymer prepared by reacting a polusocyanate and a polyalcohol. A "polyurea" is a polymer that has a structure similar to that of a polymer prepared by reacting a polusocyanate with a polyamm. It is also recognized in the art to prepare polyurethanes, that any material may have some bonds apart from the so-called primary bond. For example, a polyurethane prepared using a base polyol, but also an amine chain extender, would have some urea bonds but would still be a polyurethane. In the same way, a polyurea prepared using a polyamine base, but also using a glycol chain extender, would have some urethane bonds, but still it would be a polyurea, but in the present it could be referred to as a polyurethane. The polymers of the present invention are prepared by applying a latex to a substrate. The latex can be applied by means of painting or spraying. For the purposes of the present invention, painting is defined as the application of a material, such as a polyurethane latex, to a brush or other applicator, and then depositing the polyurethane latex on a substrate, or, alternatively, the The material can be kneaded or amalgamated on a substrate, and then spread on the substrate using a brush or other spreader element. Also for the purposes of the present invention, spraying is defined as the application of a material, such as a polyurethane latex, by atomizing the material and ejecting the atomized material on the substrate.

Another process useful with the present invention, to apply a polyurethane latex to a substrate, is immersion. In an immersion process, a substrate is lowered into a latex tank, and then removed. The latex retained on the substrate may be allowed to dry as it is, or may be spread further to make a more even application. It is possible to cover parts of the substrate to avoid having the polyurethane latex on the entire surface of the submerged substrate. Still another process to apply a latex to substrate, useful with the present invention, is the application by means of a transfer process. In a transfer process, a polyurethane latex is applied to a material that has very little ability to adhere to the polymer that forms after dehydration. This "transfer" material is contacted with another substrate that has a higher adhesive affinity for the polymer. The transfer material is removed, and the polymer is retained in the substrate. Although the above processes are preferred for applying a latex to a substrate, any known process COJG ™ O useful for one of ordinary skill in the art for applying a polyurethane latex to a substrate can be used with the present invention. The polyurethane latexes of the present invention have improved adhesion to polar surfaces. For purposes of the present invention, a polar surface is one that has a critical wetting surface tension (C? T) greater than 33 dynes / centimeter (3.3 10 ~ 4 N / centimeter). Preferably the critical wetting surface tension is 33 to 2,000 dynes / centimeter (3.3 x 10"" to 2 x 10"2 N / centimeter), more preferably 35 to 1,800 dynes / centimeter (3.5 x 10" 4 a 1.8 x 10 ~ 2 N / centimeter). Examples of materials that have polar surfaces include, but are not limited to: steel, polyethylene terephthalate, polyvinyl chloride, polyurethane, nylon-6, polyvinylidene chloride, and polycarbonate. Examples of materials having non-polar substrates include polyethylene, polypropylene, and polytetrafluoroethylene. After being applied, the polyurethane latex of the present invention is dried to produce a polymer. Any means for drying the polyurethane latex can be used, which those of ordinary skill in the art know to be useful. For example, the polyurethane latex coating can be air dried under ambient conditions, or it can be dried at elevated temperatures, optionally in reduced humidity or with forced air. The two considerations for selecting the drying conditions for the present invention are 1) not to exceed the temperature tolerance of the polyurethane polymer or the support, and 2) river to remove the water from the latex so fast that the film is interrupted due to the formation of bubbles, unless you want a bubble finish. Any drying conditions, optionally with auxiliary drying aids, such as forced air, can be used with the present invention that those of ordinary skill in the art for coating substrates with polyurethane latex know that they are useful. In the process of the present invention, a formulation of polyurethane prepolymer and a surfactant are emulsified with water. The surfactant can be present in an amount from 0.1 percent to 3.5 percent percent of the latex solids content. The surfactant may be ionic or non-ionic. If it is nonionic, the surfactant is preferably an ethoxylated alcohol, an ethoxylated fatty acid, a sorbitan derivative, a lanolin derivative, an ethoxylated nonylphenol, or an alkoxylated polysiloxane. Preferably, the surfactant is an ionic surfactant that does not react significantly with the isocyanate groups, and more preferably the surfactant is an ammonium surfactant. Suitable classes of surfactants include, but are not restricted to sulfates of ethoxylated phenols such as poly (ox? -l, 2-ethanediol) alpha- (non? Lfen? L) omega-hydroxyl ammonium salt. ?-sulfate; alkali metal fatty acid salts such as alkali metal oleates and stearates; alkali metal lauryl sulfates, quaternary ammonium surfactants; alkali metal alkylbenzenesulfonates, such as branched and linear sodium dodecylbenzenesulfonates; ammonium fluorocarbon surfactants such as alkali metal perfluoroalkylsulfonates; trialkylamide salts of dodecylbenzene sulphonic acid; ammonium salts of dodecyl-benzenesulfonic acid; trialkallamm sulfate sulfate; ammonium laupl sulfates; tnalkylamine lautelsulfates; ammonium laupl sulfonates; alkali metal lauryl sulfonates; lauryl, tpalcanolamma sulfonates; trialkyl amma lauryl sulphonates; laur dimethylamine oxide; alkali metal salt of di (sulfonamide acid) of dodecyldifene oxide; salts of tp- di (sulfonic acid) alkanolamm of dodecyldi-femide oxide; ammonium salts of di (sulfonic acid) of dodecyldiferous oxide; alkylphenol polyethoxylate; copolymers of polyoxyethylene / polyoxypropylene block; polyoxyethylene / polyoxybutylene block copolymers; and alkali metal soaps or modified resins. Particularly preferred surfactants are the trialkanolamine salt of dodecylbenzenesulfonic acid, triethanolamine salt of dodecylbenzenesulfonic acid, sodium salt of dodecylbenzenesulfonic acid, and tpetanolamyl lauryl sulfate. The polyurethane latexes of the present invention are prepared using any polyurethane formulation that can be used to prepare a polymer that is stable as an aqueous latex, without the use of an organic solvent. Included in this group are polyurethane formulations which include a polusocyanate component and an isocyanate reactive component, also known as an active hydrogen containing material or polyol. The term "polyurethane" is not limited to those polymers that include only polyurethane bonds. Those of ordinary skill in preparing polyurethanes well understand that polyurethanes also include polymers containing allophanate, biuret, carbodumide, oxazolimide, isocyanurate, uretidmdione, urea, and other linkages in addition to urethane. Similarly, polyureas can also have those bonds.

A polyurethane prepolymer useful with the present invention can be an isocyanate-terminated prepolymer. The polymer of a latex formed by the combination of a prepolymer with a chain extender and water, can be an isocyanate terminated polymer, a polymer terminated in active hydrogen, or the reaction product of a mixture of a polusocyanate and a reactive component of polusocyanate and a chain extender in almost stoic acid concentrations. The prepolymer can be formed by the reaction of the components of a prepolymer formulation that includes a polusocyanate component and an active hydrogen component. The latex is formed by the reaction of a prepolymer and a chain extender in a continuous aqueous phase. The prepolymer can be formulated, optionally, to react where the water of the continuous aqueous phase is a minor chain extender. The polusocyanate component of the prepolymer formulations of the present invention can be conveniently selected from organic polusocyanates, modified polyisocyanates, isocyanate-based prepolymers, and mixtures thereof. These may include aliphatic and cycloaliphatic isocyanates, but especially multifunctional aromatic isocyanates are preferred. The preferred polusocyanates are 2,4-, and 2,6-toluenedoctane and the corresponding isomeric mixtures; 4,4'-, 2,4'- and 2, 2 '-difeml-methan- dusocyanate and the corresponding isomeric mixtures; mixtures of 4,4'-, 2,4'- and 2-2 '-difenilmetan-dnsocyanates and polyphexpolymethylene polydimethylene-PMDI; and mixtures of PMDI and toluene dusocyanates. Also useful for preparing the polyurethanes of the present invention are the aliphatic and cycloaliphatic isocyanate compounds such as 1,6-hexamethylene dusocyanate; l-? soc? anato-3, 5, 5-tpmet? l-l-3-? soc? anatomet? l-cyclohexane; 2,4-, and 2, 6-hexah? Drotoluend? Soc? Anato, as well as the corresponding isomeric mixtures; 4,4'- 2,2'-, and 2,4'-dicyclohexylmethane-dnsocyanate, as well as the corresponding isomeric mixtures. 1,3-tetramethyl-lexolene 1,3-stearate can also be used with the present invention. For the polnsocyanate component of the formulations of the present invention, so-called modified multifunctional isocyanates, ie, products that are obtained through the chemical reactions of the dusocyanates and / or polusocyanates above, are also commonly used. The specimens are polusocyanates containing esters, ureas, biurets, allophanates, and preferably carbodnmides and / or uretommmas, the isocyanurate and / or urethane group containing dusocyanates or polusocyanates, and polyisocyanates containing carbodnide groups may also be used. urethamine and / or isocyanurate rings, having isocyanate group (NCO) contents of from 10 to 40 percent by weight; more preferably from 20 to 35 weight percent. These they include, for example, polusocyanates based on 4,4'-, 2,4'- and / or 2, 2'-d? femlmetand? soc? anato and the corresponding isomeric mixtures, 2,4- and / or 2, 6-toluene soc-anate and the corresponding isomeric mixtures; mixtures of diflectametandiisocyanates and PMDI, and mixtures of toluendusocyanates and PMDI and / or diflemlmetandiisocyanates. Suitable prepolymers to be used as the polnsocyanate component of the prepolymer formulations of the present invention are prepolymers having NCO contents of from 2 to 40 percent by weight, more preferably from 4 to 30 percent by weight. These prepolymers are prepared by a reaction of the di- and / or polusocyanates with materials including lower molecular weight diols, triols, but they can also be prepared with multivalent active hydrogen compounds such as di- and tp-ammas and di- and tp-thiols. Individual examples are aromatic polusocyanates containing urethane groups, preferably having NCO contents of from 5 to 40 weight percent, more preferably from about 20 to 35 weight percent, obtained by the reaction of dusocyanates and / or polusocyanates with, for example, lower molecular weight diols, triols, oxyalkylene glycols, dioxyalkylene glycols, or polyoxyalkylene glycols having molecular weights up to 800. These polyols can be used individually, or in mixtures as glycols of di- and /or polyoxyalkylene. For example, diethylene glycols, dipropylene glycols, polyoxyethylene glycols, ethylene glycols, propylene glycols, butylene glycols, polyoxypropylene glycols, and polyoxypropylene polyoxyethylene glycols can be used. Polyester polyols may also be used, as well as alkyl diols such as butanediol. Other useful diols include bishydroxyethyl- or bishydroxypropyl-bisphenol A, cyclohexane dimethanol, and even bishydroxyethyl hydroquinone. Particularly useful as the polusocyanate component of the prepolymer formulations of the present invention are: (i) polusocyanates having an NCO content of from 8 to 40 weight percent, containing carboduride groups and / or urethane groups, with , 4'-diffene ethanediisocyanate, or a mixture of 4,4'- and 2,4'-diflemlmethanediisocyanates; (n) prepolymers containing NCO groups, having an NCO content of from 2 to 35 weight percent, based on the weight of the prepolymer, prepared by the reaction of polyols, having a functionality of preferably 1.75 to 4, and a molecular weight of from 800 to 15,000 with 4,4'-diphemene-diisocyanate, or with a mixture of 4,4'- and 2,4'-diphenylmethane-diacyanates and mixtures of (i) and (n); and (m) 2,4- and 2,6-toluenedoctane and the corresponding isomeric mixtures. It can also be used, and PMDI is preferred in any of its forms. In this case, this one it preferably has an equivalent weight between about 125 and about 300, more preferably 130 to 175, and an average functionality of more than about 1.5. An average functionality of from 1.75 to 3.5 is more preferred. The viscosity of the polusocyanate component is preferably 25 to 5,000 centipoise (cPs) (0.025 to 5 Pa * s), but values of 100 to 1,000 cPs are preferred at 25 ° C (0.1 to 1 Pa * s) per the ease of processing. Similar viscosities are preferred where alternative polusocyanate components are selected. But, preferably, the polnsocyanate component of the formulations of the present invention is selected from the group consisting of the MDI prepolymer, PMDI, and MDI, a PMDI prepolymer, or modified MDI and mixtures thereof. The prepolymer formulations of the present invention include a polyol component. Materials containing polyfunctional active hydrogen, useful with the present invention, may include materials other than those already described hereinbefore. The activated hydrogen-terminated prepolymers, useful with the present invention, include active hydrogen attachments of the polusocyanates and the polusocyanate-terminated prepolymers described hereinbefore. The active hydrogen-containing compounds that are most commonly used in polyurethane production are those compounds that they have when minus two hydroxyl groups or amine groups. These compounds are referred to herein as polyols. Representatives of suitable polyols are generally known, and are described in publications such as High Polymers, Volume XVI, "Polyurethanes, Chemistry and Technology" by Saunders and Frisch, Interscience Publishers, New York, Volume I, pages 32-42, 44- 54 (1962), and Volume II, pages 5-6, 198-199 (1964); Organic Polymer Chemistry by K.J. ? aunders, Chapman and Hall, London, pages 323-325 (1973); and Developments in Polyurethanes, Volume I, J.M. Burst, editors, Applied Science Publishers, pages 1-76 (1978). However, any compound containing active hydrogen can be used with the present invention. Examples of those materials include those selected from the following kinds of compositions, alone or in combination; (a) alkylene oxide adducts of polyhydroxyalkanes; (b) alkylene oxide adducts of non-reducing sugars and sugar derivatives; (c) alkylene oxide adducts of phosphorus and polyphosphorous acids; and (d) alkylene oxide adducts of polyphenols. The polyols of these types are referred to herein as "base polyols". Examples of alkylene oxide adducts of polyphenol oxide adducts. The polyols of these types are referred to herein as "base polyols". Examples of alkylene oxide adducts of polyhydroxyalkanes, useful herein, are adducts of ethylene glycol, propylene glycol, 1, 3-d? H? Drox? Propane, 1, 4-d? H? Drox? Butane, and 1, 6-d? H? Drox? Hexa-no, glycerol, 1, 2, -tr? H? drox? butane, 1, 2, 6-tr? h? drox? hexane, 1, 1, 1-tmetmet? loletane, 1, 1, 1-tmetmet? lolpropane, pentaerythritol, polycaprolactone, xylitol, arabitol, sorbitol, and tol. In the present case, the adducts of propylene oxide and adducts of ethylene oxide and of propylene oxide capped with dihydroxy- and trihydroxyalkanes are preferred as alkylene oxide adducts of polyhydroxyalkanes. Other useful alkylene oxide adducts include adducts of ethylene diamine, glycerin, piperazm, water, ammonia, 1, 2, 3, 4-tetrahydroxetane, fructose, and sucrose. Also preferred are poly (oxypropylene) glycols, triols, tetroles and hexols, and any of these that are capped with ethylene oxide. These polyols also include poly (ox? Prop? Lenox? Et? Len) pol? Es. The oxyethylene content should preferably comprise less than about 80 weight percent of the total weight of the polyol, and more preferably less than about 40 weight percent. The ethylene oxide, when used, may be incorporated in any manner along the polymer chain, for example, as internal blocks, terminal blocks, or randomly distributed blocks, or any combination thereof. Another class of polyols that can be used with the present invention are "copolymer polyols", which are base polyols containing stably dispersed polymers, such as acrylomethyl-styrene copolymers.

The production of these copolymer polyols can be from reaction mixtures comprising a variety of other materials, including, for example, catalysts such as azobisisobutyropomethyl; copolymer polyol stabilizers; and chain transfer agents such as isopropanol. Polyester polyols can be used to prepare the polyurethane latexes of the present invention. Polyester polyols are generally characterized by repeating ester units which may be aromatic or aliphatic, and by the presence of primary or secondary terminal hydroxyl groups, but with the present invention any polyester which ends in at least 2 hydrogen groups may be used active. For example, the reaction product of the transesterification of glycols with polyethylene terephthalate can be used to prepare the latexes of the present invention. Polyamines, amine terminated polyethers, polymercaptans and other isocyanate-reactive compounds are also suitable in the present invention. Polusocyanate polyaddition (PIPA) active hydrogen-containing compounds can be used with the present invention. PIPA compounds are typically the reaction products of TDI and tpetanolamine. In, for example, United States Patent Number 4,374,209, issued for Rowlands, a process for preparing PIPA compounds can be found. Additionally, it is necessary that the latex formulation includes a chain extender. A greater amount of the latex chain extender in the latex formulations of the present invention is the AEEA. Minor amounts of other latex chain extenders may also be used. With the present invention, any chain extender can be used that those of ordinary skill in the art to prepare polyurethanes know to be useful, such as the minor latex chain extender. These latex chain extenders typically have a molecular weight of about 30 to 500, and have at least two groups containing active hydrogen. Polyamines are the most preferred chain extenders. Other materials, particularly water, can function to extend the length of the latex chain, and also the latex chain extenders for the purposes of the present invention. It is particularly preferred that the latex chain extender be selected from the group consisting of amine terminated polyethers such as, for example, Jeffamine D-400 from Huntsman Chemical Company, aminoethylpiperazine, 2-methylpiperazine, 1,5-diamine 3-methyl-pentane, isophoronamine, ethylenediamine, diethylenetriamine, triethylenetetramine, triethylenepentamine, ethanolamine, lysine in any of its stereoisomeric forms and salts of the same, hexanodia ina, hydrazma, and piperazma. In the practice of the present invention, the latex chain extender is frequently used as a chain extender solution in water. Although the minor portion of a latex chain extender of the present invention may be water, it is preferably a diamine different from AEEA. To the extent that a latex chain extender other than water is used in the formulations of the present invention, it is preferably used in an amount such that the active chain extender active hydrogens are less than about 90 percent of the isocyanate equivalents represented by the NCO content of the prepolymer. Even more preferably, the chain extender is present in an amount such that the active hydrogene equivalents of the chain extender are 80 to 90 percent of the isocyanate equivalents represented by the NCO content of the prepolymer. In any latex formulation of the present invention, at least 10 mole percent, but preferably at least 51 mole percent of the latex chain extender, excluding water, is AEEA. More preferably, at least 75 mole percent of the latex chain extender, excluding water, is AEEA. Including water, at least 10 percent molar, but preferably 25 percent molar latex chain extenders the present invention is AEEA. In order to calculate the amount of water acting as a latex chain extender with the present invention, the number of isocyanate equivalents of the prepolymer is determined, and from that number the total number of active hydrogen equivalents of AEEA is subtracted. and any other latex chain extender used. The rest is the number of water equivalents that act as a latex chain extender. The latexes of the present invention are not internally stabilized by the incorporation of ionic groups within the base structure of the polymer. For example, there are no sulfonate or carboxylate ions dangling from the base structure of the prepolymers of the present invention. In addition, the surfactants useful with the present invention are selected for the purpose of being substantially unreactive with the prepolymers of the present invention, when used as external stabilizers for the latexes of the present invention. In addition to the compounds containing polyisocyanates and active hydrogen, the polyurethane formulation useful for preparing the polyurethane latexes of the present invention may include additional materials called additives. For example, formulations useful with the present invention can include fillers, thixotropic agents, materials called additives. For example, Formulations useful with the present invention may include fillers, thixotropic agents, surfactants, catalysts, dispersion aids and crosslinkers. With the present invention, any additive which one of ordinary skill in the art for preparing polyurethane latexes may find useful can be used. The additives are preferably added to either the polyisocyanate or the polyol component of the prepolymer formulation, more preferably they are added to the polyol component, but may be added in any manner useful to form a polyurethane latex. The combinations, emulsions, and dispersions of the present invention are all prepared by combining the liquid components of a prepolymer formulation, and a continuous aqueous phase in the substantial absence of an organic solvent, such as toluene or acetone. The resulting latexes can be prepared by any process, or batch or continuous known to those of ordinary skill in the art to prepare latexes that are useful for preparing such latexes. Preferably, the latexes of the present invention are prepared by a continuous method. In addition, preferably, the latexes of the present invention are prepared by a phase inversion or a high internal phase portion process. A variety of devices and mechanical mixing equipment is commercially available to achieve the mixed necessary to prepare the latexes of the present invention. The mixing effectiveness can be measured by means of the average volume particle size of the resulting emulsion. An average volume particle size of less than about 5 μm is an indication that adequate mixing has been achieved. More preferably, an average volume particle size of less than about 2.0 μm is desired for the practice of this invention. U.S. Patent No. 5,539,021 to Pate, discloses a means for mixing a polyurethane latex, useful with the present invention, but any means can be used to mix the components of the prepolymer formulation of the present invention, which produce a latex having a particle size of less than about 5 μm. The latexes of the present invention can be prepared with additives included in the latex prepolymer formulations, or in the latexes themselves. Any useful additive in a latex formulation or a polyurethane latex prepolymer formulation can be used with the present invention. For example, the latexes of the present invention can be prepared with flame retardant material. In one embodiment of the present invention, the latexes of the present invention include an inorganic filler. In another embodiment of the present invention, the latexes of the present invention are prepared with a monol as an additive in the formulation of latex prepolymer. The latexes of the present invention have many applications, where it is desirable to increase the adhesion of a latex polymer to a polar surface. Exemplary applications include: pressure sensitive adhesives (PSAs), carpet linings, upholstery linings, plaste agents, conventional adhesives, coatings, non-woven binders, and textile coatings. The latexes of the present invention can be used in any of those applications, where the use of AEEA as a chain extender is not prohibited.

The following examples are provided to illustrate the present invention. The examples are not intended to limit the scope of the present invention, and should not be construed in this manner. The amounts are in parts by weight, or percentages by weight, unless otherwise indicated. The materials that were used in the examples are as defined below: The polyol is a propylene oxide (PO) capped with 12.5 percent ethylene oxide (EO), which has an equivalent weight of 1,000 g / eq. Monol 1 is a polyoxyethylene monol with a molecular weight of 950, initiated from methanol. Monol 2 is 50 percent of an ethylene oxide of molecular weight of 1800, 50 percent of heteromonol of oxide of propylene. The polyisocyanate 1 is a 50 percent mixture of 2,4'-MDI, and 50 percent of 4,4'-MDI. The polyisocyanate 2 is a mixture of 80:20 by weight of 1,4-toluene diisocyanate and 2,6-toluene diisocyanate. The polyisocyanate 3 is a 98 weight percent 4,4'-MDI. Surfactant 1 is a 20 percent solution of sodium dodecylbenzenesulfonic acid surfactant in water-, sold under the registered trade designation RHODACAL DS-10, which is a registered trade designation of Rhone Poulenc Surfactant 2 is 40 percent triethanolamine lauryl sulfate in water, sold as DESULF TLS-40, which is a registered trade designation of DEFOREST ENTERPRISES. Surfactant 3 is a 40 percent active dodecyl sodium sulfonate, sold as BIOTERGE AS-40, which is a registered trade designation of the Stepan Company. Surfactant 4 is a 22 percent solution of sodium n-dodecyl benzenesulfonic acid surfactant in water, sold under the registered trade designation POLYSTEP A-15, which is a registered trade designation of 'la Stepan Company The Physical Properties test was done in accordance with ASTM D-1708, unless stated otherwise.

EXAMPLE 1 A prepolymer was prepared by mixing 308.1 grams of Polyol, 12.0 grams of Monol 1, 8.1 grams of diethylene glycol, 199.8 grams of Polyisocyanate 1, and heating at 70 ° C for 15 hours. A polyurethane latex was prepared by weighing 50 grams of the prepolymer in an 8 oz glass bottle (2.4 x 10"4 cubic meters), which had an internal diameter of 5.6 centimeters The prepolymer was cooled to 9 ° C with a water bath The bottle was held in place and an INDCO mixing blade * was inserted (4.3 centimeters in diameter) inside the prepolymer, so that the liquid barely covered the blade. (* INDCO is a registered trade designation of INDCO, INC.) Then 60 grams of water were fed into the prepolymer at a rate of 12 grams / minute for 5.0 minutes A timer was started and stirring started at a speed of 3000 revolutions per minute At 30 seconds within the water supply, a surfactant (4.9 grams of surfactant 1) was introduced for a period of 5 seconds After a complete addition of water, 22.8 grams of a 15 percent AEEA solution in water was added via syringe, then the latex was poured out with 40 percent solids. Inside a plastic laboratory beaker of three landfills, tightly covered with aluminum foil, and allowed to stir gently overnight with a magnetic stirrer. The next day the latex was filtered through a coarse paint filter, emptied onto polypropylene, and allowed to dry under ambient conditions overnight. The resulting film was heated at 90 ° C for 1 hour, resulting in a film with the following tensile properties: final tensile strength of 2960 psi (20408 KN / M2), elongation of 698 percent, Young's modulus of 689 psi (4750 KN / M2). The latex filtered with 40 percent solids had an average particle size of 1.3 μm. The latex was then emptied onto nylon-6 by means of pipetting on a 0.25 inch x 11 inch x 1.5 inch nylon-6 substrate (0.635 centimeters x 28 centimeters x 3.81 centimeters). This was allowed to dry overnight, and then cured at 90 ° C for 1 hour. A one inch (2.54 cm) wide strip of film was marked in the center of the substrate, a cut was made along the marks, and the unused film was peeled from the sides of the substrate. The resulting one inch strip was then peeled off, using a 90 degree peel test in which the sample was moved in conjunction with the peel velocity by means of a moving attachment in an effort deformation device. The speed of detachment was 2 inches (5.2 centimeters) per minute. Average peel strength was used for five specimens, such as average peel strength. The average polymer breakdown strength in nylon-6 was 8.3 pounds / linear inch (1.7 kilograms / linear centimeter).

COMPARATIVE EXAMPLE 2 A prepolymer and a polyurethane latex were prepared and tested substantially identically to those prepared in Example 1, except that they were used 18. 45 grams of a 15 percent solution of piperazine in water, instead of 22.8 grams of a 15 percent AEEA solution, such as the latex chain extender. The physical properties were 3971 psi (27379 KN / M2) of ultimate tensile strength, elongation of 575 percent, Young's modulus of 1376 psi (9487 KN / M2). The latex filtered with 40 percent solids had an average particle size of 0.48 μm. The peel strength of the polymer in nylon-6 was 2.2 pounds / linear inch (0.39 kilograms / linear centimeter).

EXAMPLE 3 A prepolymer was prepared by mixing 7. 5 grams of dimethylolpropiomeric acid (finely ground using a mortar and a mortar grinder), 187.5 grams of Polyol, and 15 grams of Monol 1, in a round bottom flask, and heated at 80 ° C with stirring for 20 minutes. 90 grams of Polyisocyanate 2 was added, and the stirring was continued at 80 ° C for 17 hours. A polyurethane latex was prepared by weighing 50 grams of the prepolymer in an 8-ounce glass bottle (2.4 x 10 ~ 4 cubic meters), which had an internal diameter of 5.6 centimeters. The prepolymer was cooled to 9 ° C with a water bath. The bottle was held in place and an INDCO mixing blade (4.3 centimeters in diameter) was inserted into the prepolymer, so that the liquid barely covered the blade. A chronometer was started and agitation started at a speed of 3000 revolutions per minute. A solution of 1.04 grams of triethanolamine in 10 grams of water was added to the prepolymer, over a period of 30 seconds. At 30 seconds within the water feed, a surfactant (1.23 grams of Surfactant 1) was introduced for a period of 5 seconds, by means of a syringe. Then 50 grams of water was fed into the prepolymer, at a rate of 12 grams / minute for 4.16 minutes. After the complete addition of the water, 17.5 grams of a 15 percent AEEA solution in water was added via syringe. Then the latex with 41 percent solids was poured into a plastic laboratory beaker of three landfills, tightly covered with aluminum foil, and allowed to stir gently overnight with a magnetic stirrer. The next day the latex was filtered through a coarse paint filter, emptied onto polypropylene, and allowed to dry under ambient conditions overnight. The resulting film was heated at 90 ° C for 1 hour, resulting in a strong continuous film.

EXAMPLE 4 A prepolymer was prepared by mixing 5 grams of dimethylolpropiomeric acid (finely ground using a mortar and pestle), 60 grams of Polyol, and 5 grams of Monol 1, in a round bottom flask, and it was heated at 80 ° C with stirring for 20 minutes. 30 grams of Polyisocyanate 2 was added, and the stirring was continued at 80 ° C for 17 hours. A polyurethane latex was prepared by weighing 50 grams of the prepolymer in an 8-ounce glass bottle (2.4 x 10"4 cubic meters), which had an internal diameter of 5.6 centimeters. The prepolymer was cooled to 9 ° C with A water bath The bottle was held in place and an INDCO mixing blade (4.3 centimeters in diameter) was inserted into the prepolymer, so that the liquid barely covered the blade, a timer was started and the stirring started speed of 3000 revolutions per minute. A solution of 2.09 grams of triethanolamine in 10 grams of water was added to the prepolymer, for a period of 30 seconds. At 30 seconds within the water feed, a surfactant (1.23 grams of Surfactant 1) was introduced for a period of 5 seconds, by means of a syringe. Then 45 grams of water was fed into the prepolymer, at a rate of 12 grams / minute for 3.75 minutes. After complete addition of the water, 26.6 grams of a 15 percent AEEA solution in water was added via syringe. The resulting 40 percent solids latex was then poured into a three-layer plastic laboratory beaker, tightly covered with aluminum foil, and allowed to stir gently overnight with a magnetic stirrer. The next day the latex was filtered through a coarse paint filter, and emptied onto polypropylene, and allowed to dry under ambient conditions overnight. The physical properties were 773 psi (KN / M2) of ultimate tensile strength, 400 percent elongation, Young's modulus of 1236 psi (KN / M2). The peel strength of the polymer in nylon-6 was 11.1 pounds / linear inch (2.0 kilograms / linear centimeter).

EXAMPLE 5 A prepolymer was prepared by mixing 308.1 grams of Polyol, 12.0 grams of Monol 1, 8.1 grams of diethylene glycol, 199.8 grams of Polyisocyanate 1, and heating at 70 ° C for 15 hours. A polyurethane latex was prepared by weighing 50 grams of the prepolymer in an 8 oz glass bottle (2.4 x 10 ~ 4 cubic meters), which had an internal diameter of . 6 centimeters The bottle was held in place and an INDCO mixing blade (4.3 centimeters in diameter) was inserted into the prepolymer, so that the liquid barely covered the blade. Then 33.5 grams of water was fed into the prepolymer at a rate of 13.8 grams / minute for 2.42 minutes. A chronometer was started and agitation started at a speed of 3000 revolutions per minute. At 30 seconds within the water supply, a surfactant (3.5 grams of Surfactant 1) was introduced for a period of 5 seconds, by means of a syringe. After the complete addition of water, 34.2 grams of a 10 percent AEEA solution in water was added via syringe. The resulting 45 percent solids latex was then poured into a plastic laboratory beaker at three landfills, tightly covered with aluminum foil, and allowed to stir gently overnight with a magnetic stirrer. The next day the latex through a coarse paint filter, and emptied onto polypropylene, and allowed to dry under ambient conditions overnight. The resulting film was heated at 90 ° C for 1 hour, resulting in a film with the following tensile properties: final tensile strength of 2752 psi (18974 KN / M2), elongation of 723 percent, Young's modulus of 590 psi (4068 KN / M2). The latex filtered with 40 percent solids had an average particle size of 0.52 μm. The latex was then emptied onto nylon-6 by means of pipetting on a 0.25 inch x 11 inch x 1.5 inch nylon-6 substrate (0.635 centimeters x 28 centimeters x 3.81 centimeters). This was allowed to dry overnight, and then cured at 90 ° C for 1 hour. A one inch (2.54 cm) wide strip of film was marked in the center of the substrate, a cut was made along the marks, and the unused film was peeled from the sides of the substrate. The resulting one inch strip (2.54 centimeters) was then peeled off, using a 90 degree peel test in which the sample was moved in conjunction with the peel velocity by means of a moving attachment in an effort deformation device. The release rate was 2 inches (5.1 centimeters) per minute. The average peel strength was used for five specimens such as resistance to average loosening. The average polymer release resistance in nylon-6 was 5.3 pounds / linear inch (0.95 kilograms / linear centimeter). In the same way, the peel strength for latex in 304 stainless steel was tested, and was 0.30 pound / linear inch (0.054 kilogram / linear centimeter). The peel strength for polyethylene terephthalate was also tested, and was 1.9 pounds / linear inch (0.34 kilograms / linear centimeter).

COMPARATIVE EXAMPLE 6 A prepolymer and a polyurethane latex were prepared and substantially tested in an identical manner to Example 5, except that 38.0 grams were used instead of 33.5 grams of water; 3.4 grams were used instead of 3.5 grams of Surfactant 2; and 28.3 grams of a 10 percent solution of piperazine was used, instead of 34.2 grams of a 10 percent solution of AEEA. The resulting film had the following stress properties: ultimate stress resistance of 3318 psi (22877 KN / M2), elongation of 519 percent, Young's modulus of 1312 psi (9046 KN / M2). The latex filtered with 45 percent solids had an average particle size of 0.70 μm. The average polymer breakdown strength in nylon-6 was 0.12 lbs / linear inch (1.7 kilograms / linear centimeter). In the same way, the release resistance for latex in 304 stainless steel was tested, and was 0.1 pound / linear inch (0.02 kilogram / linear centimeter). The peel strength for polyethylene terephthalate was also tested, and was 0.3 pound / linear inch (0.05 kilogram / linear centimeter).

EXAMPLE 7 A polyurethane prepolymer, useful for preparing a PSA, was prepared by mixing 66 parts of Polyol; 15 parts of Monol 2; and 19 parts of Polyisocyanate 3, and heated at 70 ° C for 15 hours. A polyurethane latex was prepared by placing 50 parts of the polyurethane prepolymer in a laboratory beaker, and was stirred at high shear. Then approximately 10 parts of water were added to the prepolymer. After 10 parts of water, 1.08 parts of Surfactant 4 were added. Over a period of 5 minutes, an additional 79.8 parts of water were added. After the addition of water, 6.0 parts of a 10 percent solution of AEEA in water was added, resulting in a polyurethane that was chain extended to approximately 30 percent, based on the level of isocyanate start. Adhesive properties were measured by first coating a mylar film of three thousandths of an inch (0.08 millimeters), by spraying the latex on the mylar film, and then drying the mylar film at 160 ° F for 15 minutes. Adherence was measured by a curve adherence method, where the coated mylar film was curved on the handles of an Instron ™ test machine with the adhesive on the outside of the curve. The curve was brought into contact with a polished steel panel (PSTC, 304 stainless steel, certified by the Pressure Sensitive Tape Board) with no force beyond its own weight, and the rigidity of the curve. The curve was then immediately removed at 300 mm / minute. The adherence value of the curve was reported as the peak load to take off in the Table. Peel strength was determined by using the PSTC-2 method. This was a detachment of 90 ° to 300 millimeters / minute. The peel strength was reported as the average value on a striping length of 15 centimeters from the tape. The results were presented in the Table.

EXAMPLE 8 A PSA was prepared and tested substantially in identical manner to Example 7, except for the following. After the 10 parts of water and 1.08 parts of surfactant were added, 74.2 parts of water were added during the operation. minutes After the addition of the water, 12.1 parts of a 10 percent solution of AEEA in water was added, resulting in a polyurethane that was chain extended to approximately 60 percent, based on the level of initiation of the isocyanate. The results of the physical properties test are presented in the Table.

COMPARATIVE EXAMPLE 9 A PSA was prepared and tested substantially in identical manner to Example 7, except for the following. After the 10 parts of water and 1.08 parts of surfactant were added, 80.5 parts of water were added for 5 minutes. After the addition of the water, 5.0 parts of a 10 percent solution of piperazine in water was added, resulting in a polyurethane that was chain extended to approximately 30 percent, based on the level of initiation of the isocyanate. The results of the physical properties test are presented in the Table.

COMPARATIVE EXAMPLE 10 A PSA was prepared and tested substantially in identical manner to Example 7, except for the following. After the 10 parts of water and 1.08 parts of surfactant were added, 76.0 parts of water were added for 5 minutes. After the addition of water, 10.0 were added parts of a 10 percent solution of piperazine in water, resulting in a polyurethane that was chain extended to approximately 60 percent, based on the level of initiation of the isocyanate. The results of the physical properties test are presented in the Table.

COMPARATIVE EXAMPLE 11 A substantial PSA was prepared and tested in an identical manner to Example 7, except for the following. After the 10 parts of water and 1.08 parts of surfactant were added, 82.5 parts of water were added for 5 minutes. After the addition of the water, 3.5 parts of a 10 percent solution of ethylenediamine in water was added, resulting in a polyurethane that was chain extended at about 30 percent, based on the level of initiation of the isocyanate. The results of the physical properties test are presented in the Table.

COMPARATIVE EXAMPLE 12 A PSA was prepared and tested substantially in identical manner to Example 7, except for the following. After the 10 parts of water and 1.08 parts of surfactant were added, 78.8 parts of water were added for 5 minutes. After the addition of the water, 7.0 parts of a 10 percent solution of ethylenediamine was added to the water, resulting in a polyurethane that was chain extended to approximately 60 percent, based on the level of initiation of the isocyanate. The results of the physical properties test are presented in the Table.

Table EXAMPLE 13 A latex was prepared to be used as a carpet liner, by first preparing a prepolymer by weighing it inside a glass bottle: 2.0 parts of Monol 1, 63.59 parts of Polyol, 1.31 parts of diethylene glycol, and 33.1 Polusocyanate parts 1. The threads of the glass bottle were covered with Teflon tape, to prevent the cap would adhere to the bottle. The bottle was sealed, stirred vigorously until the homogeneity of the components was achieved, and then rolled on a bottle roller for 10 minutes. The bottle was then placed in an oven and kept at 70 ° C for 15 hours, after which it was removed and allowed to cool to room temperature before use. A latex was prepared by weighing 75 grams of the Prepolymer in an 8-ounce glass bottle (2.4 x 10 4 cubic meters), which had an internal diameter of 5.6 centimeters. The bottle was held, and an Indco type A mixing blade (4.3 centimeters in diameter) was inserted inside the prepolymer, so that the liquid barely covered the blade. Then 31.5 grams of deionized water at 20 ° C was fed into the prepolymer, at a rate of 13 grams / minute for 145 seconds, while stirring the contents of the bottle at a rate of 3000 revolutions per minute. At 30 seconds within the water feed, 6.4 grams of surfactant 3 were introduced, for a period of no more than 5 seconds, with a syringe. After the complete addition of water, 34.0 grams of a 15 percent AEEA solution in water was added, with a syringe, for a period of about 15 seconds. The resulting latex was then poured into a plastic laboratory beaker of three landfills, tightly covered with sheet aluminum, and allowed to stir gently overnight with a magnetic stirrer. The next day the latex was filtered through a coarse paint filter. The latex was then compounded by mixing 178.6 parts of latex (having 100 parts of solids) with 200 parts of calcium carbonate filler. Stirring with the latex alone began, and then the filling was added as fast as the liquid would accept the filling. A thickener was added until the composite latex had a viscosity of 23,600 cps. (23.6 Ns / square meter). The compound latex was applied upside down from a curved, nylon-level style carpet, with a crude weight of 23 ounces / square yard (780 grams / square meter) to a coating weight of 34-35 ounces / square yard ( 1152-1187 grams / square meter). A lightweight polypropylene sheet weighing 3.3 ounces / square yard (112 grams / square meter) was applied to the carpet, as a secondary liner. The carpet was dried at 200 ° C for 20 minutes, then allowed to equilibrate overnight before the test. The carpet was tested to see its physical properties, in accordance with ASTM D1335. The values obtained where the composite latex had a coating weight of 35.4 ounces / square yard (1201 grams / square meter) were a Hand of 14.7 pounds (6.67 kilograms) and a Stitch Closing of 17.9 pounds (8.17 kilograms).

Claims (10)

1. An article of manufacture comprising a substrate having a polar surface, and adhered to it, a polyurethane polymer prepared from a latex wherein: (A) the polyurethane latex is prepared from a polyurethane prepolymer which has a base structure of the polymer, substantially free of ionic groups, and is prepared from a prepolymer formulation including polyols having an average ethylene oxide content of less than 80 weight percent, (B) the prepolymer is chain extended with an aminoethyl ethanolamine chain extender (AEEA), and (C) the prepolymer and the latex are prepared in the substantial absence of an organic solvent.

2. The article of claim 1, wherein the latex is prepared by combining a polyurethane prepolymer with water, in the presence of a surfactant present in an amount of from 0.1 to 3.5 percent of the solids content of the latex.

3. The article of Claim 2, wherein the surfactant is present in an amount of from 1 to 3_5 percent of the solids content of the latex.

4. The article of Claim 1, wherein the Latex is prepared by means of a continuous process.

5. The article of claim 1, wherein the latex is prepared by a batch process.

6. The article of claim 1, wherein the prepolymer formulation includes polyols having an average ethylene oxide content of less than 40 percent by weight average ethylene oxide content.

7. The article of Claim 1, wherein at least 10 percent of the chain extender, excluding water, is AEEA.

8. The article of Claim 7, wherein at least 51 percent of the chain extender, excluding water, is AEEA.

9. A process for preparing a substrate coated with latex, which comprises applying a polyurethane latex to a polar surface of a substrate having a polar surface, wherein: (A) the polyurethane latex is prepared from a prepolymer of polyurethane having a polymer base structure, substantially free of ionic groups, and prepared from a prepolymer formulation including polyols having an average ethylene oxide content of less than 80 weight percent, (B) prepolymer is an extended chain with an AEEA chain extender, and (C) the prepolymer and the latex are prepared in the substantial absence of an organic solvent.

10. A polyurethane latex, which can be used to prepare a polyurethane polymer having improved adhesion properties, comprising a polyurethane latex, wherein: (A) the polyurethane latex is prepared from uri polyurethane prepolymer having a base structure of the polymer, substantially free of ionic groups, and prepared from a prepolymer formulation including polyols having an average ethylene oxide content of less than 80 weight percent, (B) the prepolymer is chain extended with an AEEA chain extender, and (C) the prepolymer and latex are prepared in the substantial absence of an organic solvent.