Binding of fibrous material utilizing a crosslinked polyamic acid

Abstract

Improved binder technology for use with fibrous materials is provided whereby the adjoining fibers of a fibrous material are bound in the absence of a phenol-formaldehyde reaction product. A curable binder composition is provided which comprises a water-soluble polyamic acid and an organic crosslinking agent capable of undergoing a covalent crosslinking reaction with the polyamic acid. The polyamic acid is formed by the reaction of a polycarboxylic acid and/or polyanhydride having a molecular weight of at least 150 with ammonia and/or amine compound. The binding composition is coated on a fibrous material and is heated to achieve crosslinking of the polyamic acid to form a cured water-resistant binder in association with the fibrous material wherein adjoining fibers are bound at cross-over points.

1 . An aqueous binding composition for a fibrous material comprising (a) a water-soluble polyamic acid formed by the reaction of (i) a polycarboxylic acid and/or polyanhydride having a molecular weight of at least 150 and (ii) ammonia and/or amine compound, and (b) an organic crosslinking agent capable of undergoing a covalent crosslinking reaction with said water-soluble polyamic acid when heated. 
     
     
         2 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said polycarboxylic acid and/or polyanhydride (i) has a molecular weight of 150 to 1,000,000. 
     
     
         3 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said polycarboxylic acid and/or polyanhydride (i) has a molecular weight of approximately 1,000 to 10,000. 
     
     
         4 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said polycarboxylic acid and/or polyanhydride (i) has a molecular weight of approximately 1,000 to 5,000. 
     
     
         5 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (i) is a polycarboxylic acid homopolymer or copolymer of any of acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, and mixtures thereof. 
     
     
         6 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (i) is a polyanhydride and is selected from the group consisting of polyacrylic anhydride, polymethacrylic anhydride, pyromellitic anhydride, poly(acrylic-co-methacrylic)anhydride, poly(acrylic-co-maleic)anhydride, poly(methacrylic-co-maleic)anhydride, polycrotonic anhydride, polymaleic anhydride, poly(styrene-maleic)anhydride, poly(ethylene-maleic)anhydride, poly(propylene-maleic)anhydride, poly(vinylether-maleic)anhydride, poly(butadiene-maleic)anhydride, poly(acrylamide-maleic) anhydride, malienated oils, and mixtures of the foregoing. 
     
     
         7 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (i) is poly(styrene-maleic)anhydride. 
     
     
         8 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (i) is poly(styrene-maleic)anhydride having a molecular weight of approximately 1,000 to 5,000. 
     
     
         9 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (ii) is ammonia. 
     
     
         10 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (ii) is a primary or secondary amine compound. 
     
     
         11 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (ii) is selected from the group consisting of aliphatic amine compounds, aromatic amine compounds, aliphatic/aromatic amine compounds, functionalized amine compounds of the foregoing, and mixtures of the foregoing. 
     
     
         12 . The aqueous binding composition for a fibrous material according to  claim 1  wherein (ii) is glycine. 
     
     
         13 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said organic crosslinking agent (b) is selected from the group consisting of polyols, polyamines, polyalkanolamines, and mixtures thereof. 
     
     
         14 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said organic crosslinking agent (b) is selected from the group consisting of glycols, glycol ethers, polyamines, alkanolamines, polyester polyols, polyether polyols, acrylic polyols, urethane polyols, polysaccharides, polyvinyl alcohol, and mixtures thereof. 
     
     
         15 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said organic crosslinking agent (b) is selected from the group consisting of diethanolamine, triethanolamine, and mixtures thereof. 
     
     
         16 . The aqueous binding composition for a fibrous material according to  claim 1  wherein said organic crosslinking agent (b) is a water-soluble Michael adduct crosslinking agent having reactive hydroxyl end groups formed by the addition reaction of a Michael acceptor compound having alpha-beta unsaturation attached to an electron withdrawing group and a nucleophilic compound serving as a Michael donor capable of reaction with said Michael acceptor. 
     
     
         17 . The aqueous binding composition for a fibrous material according to  claim 16  wherein the electron withdrawing group of said Michael acceptor compound is selected from ester groups, acid groups, amide groups, nitro groups, nitrile groups, ketone groups, aldehyde groups, and mixtures thereof, and said nucleophilic compound serving as a Michael donor is selected from the group consisting of alkylamines, alkanolamines, thiols, and mixtures thereof. 
     
     
         18 . The aqueous binding composition for a fibrous material according to  claim 16  wherein the nucleophilic compound serving as a Michael donor is a mono- or dialkanol amine having  2  to  4  carbon atoms per alkanol group. 
     
     
         19 . The aqueous binding composition for a fibrous material according to  claim 16  wherein the nucleophilic compound serving as a Michael donor is selected from the group consisting of diethanolamine, triethanolamine, and mixtures thereof. 
     
     
         20 . A process for binding a fibrous material comprising:
 (1) applying to a fibrous material as a coating an aqueous binding composition comprising (a) a water-soluble polyamic acid formed by the reaction of (i) a polycarboxylic acid and/or polyanhydride having a molecular weight of at least 150 and (ii) ammonia and/or amine compound, and (b) an organic crosslinking agent capable of undergoing a covalent crosslinking reaction with said water-soluble polyamic acid when heated, and   (2) heating said coated fibrous material to achieve crosslinking of the polyamic acid to form a water-resistant cured binder in association with said fibrous material wherein adjoining binders are bound at cross-over points.   
     
     
         21 . The process of  claim 20 , wherein the fibrous material comprises mineral fibers. 
     
     
         22 . The process of  claim 20 , wherein the fibrous material comprises glass fibers. 
     
     
         23 . The process of  claim 20 , wherein the fibrous material comprises polymeric fibers. 
     
     
         24 . The process of  claim 20 , wherein the polycarboxylic acid and/or polyanhydride (i) has a molecular weight of 150 to 1,000,000. 
     
     
         25 . The process of  claim 20 , wherein the polycarboxylic acid and/or polyanhydride (i) has a molecular weight of approximately 1,000 to 10,000. 
     
     
         26 . The process of  claim 20 , wherein the polycarboxylic acid and/or polyanhydride (i) has a molecular weight of approximately 1,000 to 5,000. 
     
     
         27 . The process of  claim 20 , wherein (i) is a polyanhydride and is selected from the group consisting of polyacrylic anhydride, polymethacrylic anhydride, polymellitic anhydride, poly(acrylic-co-methacrylic)anhydride, poly(acrylic-co-maleic)anhydride, poly(methacrylic-co-maleic)anhydride, polycrotonic anhydride, polymaleic anhydride, poly(styrene-maleic)anhydride, poly(ethylene-maleic)anhydride, poly(propylene-maleic)anhydride, poly(vinylether-maleic)anhydride, poly(butadiene-maleic)anhydride, poly(acrylamide-maleic)anhydride, malienated oils, and mixtures of the foregoing. 
     
     
         28 . The process of  claim 20 , wherein (i) is a polycarboxylic acid homopolymer or copolymer of any of acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, and mixtures thereof. 
     
     
         29 . The process of  claim 20 , wherein (i) is poly(styrene-maleic)anhydride. 
     
     
         30 . The process of  claim 20 , wherein (i) is poly(styrene-maleic)anhydride having a molecular weight of approximately 1,000 to 5,000. 
     
     
         31 . The process of  claim 20 , wherein (ii) is ammonia. 
     
     
         32 . The process of  claim 20 , wherein (ii) is a primary or secondary amine compound. 
     
     
         33 . The process of  claim 20 , wherein (ii) is selected from the group consisting of aliphatic amine compounds, aromatic amine compounds, aliphatic/aromatic amine compounds, functionalized amine compounds of the foregoing, and mixtures of the foregoing. 
     
     
         34 . The process of  claim 20 , wherein (ii) is glycine. 
     
     
         35 . The process of  claim 20 , wherein said organic crosslinking agent (b) is selected from the group consisting of polyols, polyamines, polyalkanolamines, and mixtures thereof. 
     
     
         36 . The process of  claim 20 , wherein said organic crosslinking agent is selected from the group consisting of glycols, glycol ethers, polyamines, alkanolamines, polyester polyols, polyether polyols, acrylic polyols, urethane polyols, polysaccharides, polyvinyl alcohol, and mixtures thereof. 
     
     
         37 . The process of  claim 20 , wherein said organic crosslinking agent is selected from the group consisting of diethanolamine, triethanolamine, and mixtures thereof. 
     
     
         38 . The process of  claim 20 , wherein said water-soluble polyamic acid is formed by the reaction of poly(styrene-maleic)anhydride having a molecular weight of approximately 1,000 to 5,000 and ammonia, and said water-soluble organic crosslinking agent is selected from the group consisting of polyols, polyamines, polyalkanolamines, and mixtures thereof. 
     
     
         39 . The process of  claim 20 , wherein said organic crosslinking agent is a Michael adduct crosslinking agent having reactive hydroxyl end groups formed by the addition reaction of a Michael acceptor compound having alpha-beta unsaturation attached to an electron-withdrawing group and a nucleophilic compound serving as a Michael donor capable of reaction with said Michael acceptor. 
     
     
         40 . The process of  claim 39 , wherein said Michael acceptor compound is selected from ester groups, acid groups, amide groups, nitro groups, nitrile groups, ketone groups, aldehyde groups, and mixtures thereof, and said nucleophilic compound serving as a Michael donor is selected from the group consisting of alkylamines, alkanolamines, thiols, and mixtures thereof. 
     
     
         41 . The process of  claim 40 , wherein said nucleophilic compound serving as a Michael donor is selected from the group consisting of diethanolamine, triethanolamine, and mixtures thereof. 
     
     
         42 . The process of  claim 20 , wherein said water-soluble polyamic acid is formed by the reaction of poly(styrene-maleic)anhydride having a molecular weight of approximately 1,000 to 5,000 and ammonia, and said organic crosslinking agent is a Michael adduct formed by the reaction of a Michael acceptor compound having alpha-beta unsaturation attached to an electron-withdrawing group selected from the group consisting of acrylic acid, maleic acid, maleic anhydride, and mixtures thereof, and a Michael donor selected from mono- or dialkanolamines having 2 to 4 carbon atoms per alkanol group, and mixtures thereof. 
     
     
         43 . The process of  claim 20 , wherein said heating (2) is carried out at a temperature of approximately 160 to 250° C. 
     
     
         44 . The process of  claim 20 , wherein said heating (2) is carried out at a temperature of approximately 200° C. 
     
     
         45 . The process of  claim 20 , wherein at the conclusion of (2) said water-resistant cured binder is provided in association with said fibrous material in a concentration of approximately 1 to 50 percent by weight based on the weight of the fibrous material. 
     
     
         46 . A fibrous material coated with the water-resistant cured binder produced in accordance with the process of  claim 45 , wherein adjoining fibers are bound at cross-over points. 
     
     
         47 . A-fiberglass building insulation product coated with the water-resistant cured binder produced in accordance with the process of  claim 45 , wherein adjoining fibers are bound at cross-over points. 
     
     
         48 . A spun-bonded polymeric fibrous mat coated with a water-resistant cured binder produced in accordance with the process of  claim 45 , wherein adjoining fibers are bound at cross-over points. 
     
     
         49 . A ceiling or flooring tile comprising as fibrous reinforcement a fibrous mat coated with water-resistant cured binder produced by the process of  claim 45  wherein adjoining fibers are bound at cross-over points. 
     
     
         50 . An asphalt shingle comprising as fibrous reinforcement a fibrous mat coated with a water-resistant cured binder produced by the process of  claim 45  wherein adjoining fibers are bound at cross-over points. 
     
     
         51 . A fiberglass insulation product coated with a water-resistant cured binder produced by the process of  claim 20 , wherein said water-soluble polyamic acid is formed by the reaction of poly(styrene-maleic)anhydride having a molecular weight of approximately 1,000 to 5,000 and ammonia, and said organic crosslinking agent is a Michael adduct formed by the reaction of (i) a Michael acceptor compound having alpha-beta unsaturation attached to an electron-withdrawing group selected from the group consisting of acrylic acid, maleic acid, maleic anhydride, and mixtures thereof, and a Michael donor selected from mono- or dialkanolamines having 2 to 4 carbon atoms per alkanol group and mixtures thereof.