MXPA99011296A - Carpet back coating composition having increased wet strength - Google Patents

Abstract

A carpet back coating composition which is an aqueous emulsion polymerization product of ethylene, vinyl acetate, and a ethylenically unsaturated hydroxy-functional monomer to form an emulsion copolymer which is combined with a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate, and multifunctional epoxide. Carpets prepared with the carpet back coating compositions exhibit improved wet strength. The improvement in wet strength is achieved by means of crosslinking reactions which do not generate volatile organic compounds as by-products.

Description

* BACK CARPET COMPOSITION COMPOSITIONS WHICH HAVE RESISTANCE TO INCREASED HUMIDITY FIELD OF THE INVENTION This invention relates to a carpet backing composition which is an aqueous emulsion polymerization product of ethyl, vinyl acetate and an ethylenically hydroxy functional monomer. unsaturated to form an emulsion copolymer which is combined with a crosslinking agent selected from the group consisting of Multifunctional aziridine, multifunctional isocyanate and multifunctional epoxy. Carpets prepared with carpet backing compositions exhibit improved moisture resistance. The improvement in the resistance to moisture is achieved through crosslinking reactions that do not generate volatile organic compounds as by-products. An important characteristic of the carpet, especially carpet slabs, is the resistance to moisture. Currently carpets can be routinely exposed to water from the cleaning process with steam. In such situations, the moisture resistance of the carpet is important since inadequate moisture resistance can cause the carpet edges to be frayed, dented or pleated from the carpet slab. Such changes in the surface of carpets are undesirable and can result in personal injury.

Carpets generally comprise a padded substrate with bunches of yarn in the form of cut or uncut loops extending upwardly from the padded substrate to the shape of a velvety surface. In the case of tufted carpets, the yarn is inserted into the padded substrate by padding needles and a pre-coat or protective hair applied to it. In the case of non-tufted or agglutinated velvety carpets, the fibers are embedded and maintained in place by the protective hair composition. With both types of carpets, the carpet also usually includes an agglomerate of secondary fabric to the primary bottom fabric. The secondary bottom fabric provides extra carpet padding, noise absorbing, added dimensional stability, and functions as a heat insulator. The secondary backing fabric commonly used as fabrics, PVC plastisol, polyurethane, foam sheet such as PVC or urethane and pitch. The physical properties of a carpet precoat or carpet protective fabric, hereinafter referred to as a "carpet backcoating", are important. Such properties include the following: (1) it must be capable of being applied to a carpet and dried using conventional processes and equipment; (2) it must provide excellent addition to the velvety fibers to firmly secure the underlying fabric in the tufted and non-tufted constructions; (3) must have low smoke density values and high flame retardant properties; (4) it must maintain sufficient softness and flexibility, even with a high filling or low temperature load, it allows the carpet, if prepared in a continuous way, to be easily rolled and unrolled during the installation and, in the case of carpet slabs that the slab has sufficient rigidity as well as that it is easily placed in its place. Typical carpet slab bottoms have been prepared either from all polyvinyl chloride plastisol (PVC) matrices or a pre-layer combination of ethylvinyl acetate with a plastisol PVC secondary coating. While PVC plastisols show good resistance to water, the disadvantage with plastisol PVC is a high degree of smoke generation that can present a serious safety issue. Carpet prepared with a pre-layer of ethylevinyl acetate with a secondary PVC fabric shows low smoke density values and high flame retardant properties, but tends to have lower moisture resistance than all PVC-based plastisol carpets as evidenced through low binding values of bunch of moisture.

Japanese Patent No.56-140 152 discloses a fiber agglomerating agent which is composed of (A) an aqueous dispersion of a copolymer composed of 0.1-3.0 parts by weight of ethylenically unsaturated monocarboxylic acids or etholynically unsaturated polyhydric carboxylic acids per 100%. parts by weight of ethylene vinyl acetate copolymer; and (B) an aqueous dispersion of a compound containing groups of two or more multifunctional aziridine. However, the disadvantages of the compositions described in Japanese Patent No. 56-140152 is the poor stability of the compound due to the presence of carboxyl groups in the copolymer. US Patent No. 3,458,485 describes a solution of resin prepared from styrene, vinylidene or vinyl chloride and 13 to 45 weight percent hydroxyethyl acrylic, based on the weight of the copolymer, which was combined with 6 to 20 percent by weight. weight, based on the weight of the copolymer, of a crosslinking agent to form a thermosetting resin mixture. However, the disadvantage of the resin solution described in US Pat. No. 3,458,485 is the amount of hydroxyethyl acrylic and the crosslinking agent that provides the prohibitively expensive resins for use as carpet coatings.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a crosslinkable carpet coating composition that is applied to carpet and dried, cured without emitting volatile organic compounds (VOC's) as a by-product of the crosslinking reaction. It is another object of the invention to provide a carpet backing having low smoke density values and high flame retardant properties. It is also an object of the invention to provide carpet with improved moisture resistance that resists the tendency of fraying the edge and limiting / weighing it when exposed to moisture or water. It is a further object of the invention to provide a carpet backing that maintains sufficient softness and flexibility, even with a high filler load and at a low temperature, to allow the carpet, if prepared in a continuous manner, to be easily rolled and unrolled during the installation and, in the case of carpet slabs, that the slab has sufficient rigidity as well as that it is easily placed in its place. With respect to the foregoing, and other objects, the present invention provides a crosslinkable carpet coating composition comprising: (i) an aqueous emulsion polymerization product of (a) from about 4 to about 25 weight percent of ethylene; (b) from about 67 to about 95 weight percent vinyl acetate; and (c) from about 0.1 about 8 weight percent of at least one hydroxyethylenically unsaturated functional monomer. When the percentages by weight of the monomers used to prepare the copolymer are based on the weight of (a) + (b) + (c); and (ii) from about 0.5 to about 9 weight percent, based on the weight of the copolymer, of a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate, and multifunctional epoxide, wherein the crosslinking reaction does not generate compounds Volatile organic compounds as secondary products. Preferably the ethylenically unsaturated hydroxy functional monomer has the formula R1 O CH, C OR R * wherein R1 is hydrogen or methyl and R2 is a hydroxyalkyl group having from 2 to 6 carbon atoms. According to another aspect of the invention there is provided a method for treating carpets to improve the moisture resistance of the carpet, the method comprising: (I) applying a carpet backing composition to the carpet or bunches of yarn, the Carpet backing composition comprises: (i) an aqueous emulsion polymerization product of (a) from about 4 to about 25 weight percent ethylene; (b) from about 67 to about 9-5 weight percent vinyl acetate; and (c) from about 0.1 to about 8 weight percent of an ethylenically unsaturated hydroxy functional monomer, wherein the percentages by weight of the monomers used to prepare the copolymer are based on the weight of (a) + (b) + (c), and (ii) from about 0.5 to about 9 weight percent, based on the weight of the copolymer of a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate, and multifunctional epoxy to form a composition of back coating of crosslinkable carpet; and (II) drying the crosslinkable carpet backing composition at a temperature sufficient to react the aziridine as isocyanate or functional epoxide groups in the crosslinking agent with the hydroxy functional groups in the copolymer, where the crosslinking reaction does not generate organic compounds volatile as secondary products. The carpet backings of the present invention show significant properties in moisture resistance when compared to commercially available carpet backings. Additionally, carpets prepared with the carpet backsheet of the invention may show improved assistance to fraying of the edges and / or embossing and curling when exposed to moisture or water. However, the carpet backing compositions of the invention require only a minimal amount of multifunctional isocyanate crosslinking agent or multifunctional crosslinking aziridine to achieve a significant increase in moisture resistance as evidenced by the highest binding values of bunches wet.

DESCRIPTION OF THE INVENTION The invention provides an improved carpet backing composition. The composition is applied to all carpets that include tufted, non-woven, perforated, knotted, and hooked carpets. Carpets treated using the carpet backing composition of the invention exhibit improved moisture resistance as evidenced by the highest values of wet bunches when compared to the prior art coating compositions. The carpet backing composition is an aqueous emulsion polymerization product of ethylene, vinyl acetate and a hydroxyfunctional ethylenically unsaturated monomer to form an emulsion copolymer which was combined with a crosslinking agent selected from the group consisting of aziridine. multifunctional multifunctional isocyanate and multifunctional epoxide: None of the volatile organic compounds are generated during the crosslinking of the aziridine, isocyanate, or functional epoxides in the crosslinking agent with the hydrofunctional groups in the copolymer. prepare as an emulsion copolymer As used herein, "emulsion" means a dispersion of particulate matter in an aqueous phase that contains an emulsifier or surfactant suitable for preparing the emulsion.

The amount of ethylene monomer used to prepare the emulsion copolymer is from about 4 to about 25 weight percent, preferably from about 10 to about 20 weight percent, based on the total weight of the monomers used to weigh the copolymer . The amount of vinyl acetate used to prepare the emulsion copolymer is from about 67 to about 95 weight percent, preferably from about 75 to about 90 weight percent, based on the total weight of the monomers used to prepare the copolymer . The hydroxyfunctional ethylenically unsaturated monomer has the formula: R1 O CH, C O R¿ In the above formula for the hydroxy-functional monomer, R1 is hydrogen or methyl and R2 is a hydroxyalkyl group having from 2 to 6 carbon atoms. Examples of the hydroxy-functional monomers are hydroxyethyl acrylate, hydroxybutyl acrylate, hydropropyl acrylate. The combinations of the hydroxy-functional monomers can also be used. The amount of hydroxyfunctional ethylenically unsaturated monomer for preparing the emulsion copolymer is from about 0.1 about 8 weight percent, preferably about 1 about 5 weight percent, based on the total weight of the monomers used to prepare the copolymer. The emulsion copolymer was prepared using conventional procedures that are known in the art, using either batch processes, addition of continuous monomers or addition of increased monomers. The emulsion polymer is generally prepared as an emulsifier and / or a protective colloid which are known in the art. Suitable emulsifiers include anionic, cationic, nonionic or mixtures thereof. Anionic emulsifiers are, for example, alkyl sulfonates, alkylaryl sulphonates, alkyl sulfates, hydroxylalkanols sulfates, alkyl and alkylaryl disulfonates, sulfonated fatty acids, sulphates and phosphates of polyethyoxylated alkanols and alkyphenols, as well as esters of sulfosuccinic acid. Suitable cationic emulsifiers are, for example, quaternary alkyl ammonium salts and quaternary alkyl phosphonium salts. Examples of suitable non-anionic emulsifiers are the addition products of 5 to 50 moles of ethylene oxide causing addiction for straight chain or branched chain alkanols with 6 to 22 carbon atoms, or alkylphenols, or high fatty acids, or highly fatty acid amines, or high alkyl primary and secondary amines; as well as block copolymers of propylene oxide with ethylene oxide and mixtures thereof. Suitable protective colloids include polyvinyl alcohols, ionically modified starches, water soluble starches, starch esters, polyacrylic acid, carboxymethyl cellulose, natural gums, gelatin, synthetic polymers and water soluble cellulose ethers such as hydroxyethyl cellulose. Essentially any type of free radical generator can be used to initiate free radical emulsion polymerization. For example, the free radical generates chemical compounds, ultraviolet light or radiation can be used. The selection of free radical generates dependent chemical compounds in the desired polymerization ratio and the final polymer properties. Some representative examples of the free radical initiators are commonly used including those of various persulfates, percarbonates, perborates, peroxides, organic reducing agents such as ascorbic acid and combinations thereof. Free radical emulsion polymerization will typically lead to temperatures that are within the range of about 30CC to about 100 ° C. This is generally preferred for the polymerization to raise to a temperature that is within the range of 50 ° C to about 90 ° C. The emulsion polymerization is carried out * to a PH from about 2 to about 7, preferably at a pH from about 3 to about 5. To maintain the pH range it can be used to work in the presence of customary buffer systems, for example, in the presence of alkali metal carbonates, acetates of alkali metal and alkali metal phosphonates. Polymerization regulators such as percaptans, aldehydes, chloroform, methylene chloride and trichlorethylene can also be used. Other ingredients known in the art can be used for various purposes in emulsion polymerization, such as acids, salts, chain transfer agents, and chelating agents can be employed. Although the solid contents and emulsion viscosity may vary from the typical total solid contents they are defined as the non-volatile components of the emulsion, they are in the range from about 20 about 80 weight percent, preferably 50 to 75 weight percent, based on the total weight of the emulsion.

The emulsion copolymer is combined with a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate, and multifunctional epoxide to form a carpet backing composition. In the carpet backing of the invention, the multifunctional aziridine, multifunctional isocyanate or epoxide groups in the crosslinking agent react with the epoxy groups in the copolymer. The crosslinking reaction of the invention does not generate volatile organic compounds as a by-product of the crosslinking reaction. Crosslinking occurs during film formation and bonding. The amount of crosslinking agent formulated with the emulsion copolymer is from about 0.5 to about 9 weight percent, preferably from about 1.5 to about 7 weight percent, based on the weight of the copolymer. The carpet backcoating compositions may further contain, in addition to the above ingredients, at least one additive. Suitable additives are, for example, dispersants, flame retardants, antimicrobials, foaming agents, thickeners and colorants. Such additional ingredients and their amounts are known in the art, so that only fillers, catalysts and acids will be referred to in more detail. Suitable fillers are, for example, calcium carbonate, aluminum hydroxide, clay or talc. In carpet backcoating compositions, one or more catalysts or acids may optionally be included to accelerate the reaction between the crosslinking agent and the hydroxy groups in the copolymer. However, the reaction between the crosslinking agent and the epoxy groups in the copolymer does not require a catalyst or acid. The present inventors have determined that a pH of less than 7 is preferred for the crosslinking reaction to take place, therefore a small amount of acid or acid catalysts can be added to the combination of the emulsion and the crosslinking agent to lower the pH if it is necessary. The carpet backing composition is dried, cut into the carpet or bunches of yarn at a temperature sufficient to react with the crosslinking agent and the hydroxyl groups in the copolymer. The treated carpet or bunches of yarn are dried, cut at normal temperatures provided by either a drying unit used in the carpet manufacturing process such as a heated steam dryer cylinder or in an oven. The drying temperatures are generally in the range from about 90 ° C to about 200 ° C. Such temperatures allow the water to be removed and induce crosslinking of the crosslinking agent and the hydroxy groups in the copolymer. The residence time of the carpets covered with the compositions of the invention in the drying unit or "oven ranges from about 30 seconds to about 15 minutes depending on the temperature.The current residence time for a particular sample of carpets depends on temperature, type of threads, percent solids of the carpet covering compounds, materials used to prepare carpet and the construction of the carpet. Preferably, the time and temperatures for curing the crosslinking agent with the hydroxy groups in the copolymer average from about 60 seconds to about 200 seconds at a temperature averaged from about 80 ° C to about 200 ° C, preferably from about 100 ° C to about 180 ° C. ° C. After the carpet of the carpet backing composition applied thereto is dried / cured, subsequent coatings or additives can be applied to the carpet. Generally, the amount of carpet backing composition is from about 10 to about 50 ounces per square yard, preferably from about 25 to about 35 ounces per square yard. In the case of the carpet slab, the amount of carpet backing composition in the slab is preferably from about 20 to about 35 ounces per square yard. The carpet backsheet of the present invention demonstrates significant improvements in moisture resistance when compared to commercially available carpet backsheets, and resistance to tendency for edge trimming and / or scaling and curling when exposed to moisture or water. In addition, the carpet backing compositions of the invention require only a minimal amount of functional aziridine crosslinking agent or multifunctional isocyanate to achieve significant increases in moisture resistance as evidenced by the highest values of bundle binding in damp. The following non-limiting examples illustrate traditional aspects of the invention. EXAMPLE 1 Preparation of the aqueous emulsion copolymer. Three aqueous emulsion copolymers are prepared according to Table 1. Emulsion copolymer No. 3 was Dur-O-Set E-190HS which is available from National Starch and Chemical Company.

TABLE I EXAMPLE 2 Preparation of the Carpet Rear Coating Composition. The aqueous emulsion copolymers prepared in the Example 1 are incorporated into Formulation I to form a carpet backing composition. Formulation I Parts by Weight Emulsion copolymers in 60% solids 400 Water 25 Filler CaCO3 506 Other 21.2 Crosslinker 4-6 [Other = Flame retardants, antimicrobials, etc.] The compositions of carpet aftercoating were determined by having a percentage in 80% solids and Viscosity. Brookfield from 3,500 to 8,000cps at 20 rpm using a # 3 winch.

EXAMPLE 3 Preparation of the Rear Coating Composition of Carpet . The aqueous emulsion copolymers prepared in the Example 1 was incorporated into Formulation II to form a carpet backing composition. Formulation II Parts by Weight Emulsion copolymers in 60% solids 400 Dispersant (polyacrylate) 2 Filler CaCO3 464 Starch 15 Thickener 0-3 Crosslinker 4-16 Carpet backing compositions were determined to have a solids percentage of 81% and a Brookfield Viscosity of 8,000 to 12,000 cps at 20 rpm using a # 3 winch. EXAMPLE 4 Samples of the Coated Carpet with a Carpet Rear Coating Composition. The following carpet samples were used to evaluate the carpet backing compositions prepared in Example 2 and 3. Carpet Styles Weight (uncoated) Description Carpet Style A 26-28 oz / yd2 Nylon Threads Polyester Quilted Substrates Measurement stitch pattern Carpet Style B 26-28 oz / yd2 Nylon Threads Polypropylene Padded Substrates Straight Stitch Pattern The carpet backing compositions prepared in Example 2 and 3 are abrasion coated on Style A and B Carpets using either a foamed or unfoamed compound to achieve appropriate additions. The coatings are dried for 8 minutes at 1-30 ° C. Coating weights of 25-50 oz / yd2 were achieved. The carpets were then coated with the plastisol compound of polyvinyl chloride (75 thousand coated) and cured for 7 minutes at 149 ° C. The resulting tests were summarized in Table II.

TABLE II Az # is a multifunctional aziridine (PFAZ-322) available from Sybron Chemical Inc. Az # 2 is a multifunctional aziridine (XAMA-7) available from EIT Inc. Iso # l is a diisocyanate (RUBINATE 9259) available from ICI Chemical Company Iso # 2 is a diisocyanate (RUBINATE 9472) available from ICI Chemical Company Iso # 3 is a diisocyanate (RUBINATE 9473) available from ICI Chemical Company The test results in Table II clearly show the carpets treated with the coating compositions The carpet backing according to the invention containing a copolymer of ethylene, vinyl acetate and a hydroxyfunctional ethylenically unsaturated comonomer formulated with a multifunctional aziridine or isocyanate crosslinking agent demonstrates significantly improved moisture resistance. Improvements to moisture resistance were demonstrated by high values of wet bundling when compared by commercially available carpet backings or carpet backings outside the scope of the invention. Carpet Samples No. 1, 6 and 8, for example, which are treated with a carpet backing composition prepared from an ethylene vinyl acetate copolymer, but crosslinking agent, show deficient values of bundle attachments in moisture, and in this way show poor resistance to moisture. While the invention has been described with particular reference to certain embodiments thereof, it will be understood that changes and modifications may be made by those with ordinary skill in the art within the spirit and scope of the following claims.

Claims (15)

WHAT IS REVIVED IS: 1. A carpet backing composition comprising: (i) an aqueous emulsion polymerization product of (a) from about 4 about 25 weight percent ethylene; (b) from about 67 to about 95 weight percent vinyl acetate; and (c) from about 0.1 about 8 weight percent of at least one hydroxyfunctional ethylenically unsaturated monomer, wherein the weight percentages of the monomers used to prepare the copolymer are based on the weight of (a) + (b) + (c); and (ii) from about 0.5 to about 9 weight percent based on the weight of the copolymer of a cross-linking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate, and multifunctional epoxide, wherein the crosslinking reaction does not generate organic compounds volatile as secondary products. 2. The crosslinkable carpet backing composition, comprising: (i) an aqueous emulsion polymerization product of (a) from about 10 to about 20 weight percent ethylene; (b) from about 75 to about 90 weight percent vinyl acetate; (c) from about 1 to about 5 weight percent of a hydroxyfunctional ethylenically unsaturated monomer having the formula
1. R1 O
2. CH, C C O wherein R1 is hydrogen or methyl and R2 is a hydroxyalkyl group having from 2 to 6 carbon atoms, and those by certain by weight of the monomers used to prepare the copolymer are based on the weight of (a) + (b) + (c); and (ii) from about 1.5 to about 7 weight percent, based on the weight of the copolymer, of a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate and multifunctional epoxide, wherein the crosslinking reaction does not generate organic compounds volatile as secondary products.
3. 3. The carpet backing composition according to claim 2, wherein the hydroxyfunctional ethylenically unsaturated monomer is selected from the group consisting of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate and combinations thereof.
4. 4. The carpet backing composition according to claim 3, wherein the hydroxyfunctional ethylenically unsaturated monomer is hydroxyethylacrylate.
5. 5. The carpet backing composition according to claim 1 further comprises an additive selected from the group consisting of fillers, dispersants, flame retardants, antimicrobials, foaming agents, thickeners, colorants, and catalysts. The subsequent coating composition of carpet according to claim 5, wherein the filler is selected from the group consisting of calcium carbonate, aluminum hydroxide, clay, talc, combinations thereof. 7. The carpet backing composition according to claim 1. 5, wherein the catalyst is a Lewis acid. 8. A method for treating carpets to improve the moisture resistance of the carpet, the method comprises: • _. • 27 (I) applying a carpet backing composition to the carpet or bunches of yarn, the carpet backing composition comprising: (i) an aqueous emulsion polymerization product of (a) from about 4 to about 25 percent by weight of ethylene; (b) from about 67 to about 95 10 weight percent vinyl acetate; and (c) from about 0.1 to about 8 weight percent of at least one hydroxyfunctional ethylenically unsaturated monomer, wherein the percentages by weight of the monomers used to prepare the copolymer are based on the weight of (a) + ( b) + (c); and (ii) from about 0.5 to about 9 weight percent, based on the weight of the copolymer, of a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate and multifunctional epoxide to form a carpet backing composition.; (II) drying the back coating composition of the crosslinkable carpet at a temperature Sufficient to react the aziridine, isocyanate, or functional epoxide groups in the crosslinking agent with the hydroxy functional groups in the copolymer, wherein the crosslinking reaction does not generate volatile organic compounds as by-products. 9. A method for treating carpets to improve the moisture resistance of the carpet, the method comprising: (I) applying a carpet backing composition to the carpet or bunches of yarn, the carpet backing composition comprising : (i) an aqueous emulsion polymerization product of (a) from about 10 to about 20 weight percent ethylene; (b) from about 75 to about 90 weight percent vinyl acetate; and (c) from about 1 to about 5 weight percent of an ethylenically unsaturated hydroxy-functional monomer having the formula R 'O CH, C O R ^ V 29 wherein R is hydrogen or methyl and R 2 is a hydroxyalkyl group having from 2 to 6 carbon atoms, and the percentages by weight of the monomers used to prepare the copolymer are based on the weight of (a) + (b) + (c); and (ii) from about 1.5 to about 7 weight percent, based on the weight of the copolymer, of a crosslinking agent selected from the group consisting of multifunctional aziridine, multifunctional isocyanate and multifunctional epoxide; and (II) drying the crosslinkable carpet back coating composition at a temperature sufficient to react the aziridine, isocyanate, or functional epoxide groups in the crosslinking agent with the hydroxy functional groups in the copolymer, wherein the reaction 15 r.Anticulant does not generate volatile organic compounds as byproducts. The method according to claim 8 wherein the pH of the combination of the emulsion copolymer and a crosslinking agent is less than 7. The method according to claim 8 wherein the amount of subsequent coating composition. of carpet on the carpet is from about 10 to about 50 ounces per square yard. 12. The method according to claim 11, 25 wherein the amount of coating composition * «J«. 30 Rear carpet on the carpet is from about 25 to about 35 ounces per square yards. A carpet treated with the method according to claim 8. 14. A carpet having the carpet backcoating composition according to claim 1. 15. A carpet having the carpet backcoating composition in accordance with the 10 claim 2. EXTRACT OF THE INVENTION A carpet backing composition which is an aqueous emulsion polymerization product of ethylene, vinyl acetate, and a hydroxyfunctional ethylenically unsaturated monomer to form an emulsion copolymer which is combined with a crosslinking agent of the group consisting of of multifunctional aziridine, multifunctional isocyanate and multifunctional epoxide, the carpets prepared with the carpet backing composition show improved moisture resistance. The improvement in moisture resistance is achieved through crosslinking reactions that do not generate volatile organic compounds as byproducts.