Crosslinkable acrylate adhesive polymer composition

Abstract

A pre-adhesive syrup copolymer composition comprising an acid functional acrylate solute copolymer, a monomer solvent mixture, and a polyaziridine crosslinking agent is disclosed.

1 . A syrup polymer composition comprising:
 a) first component solute copolymer comprising:
 1) 100 parts by weight of an (meth)acrylic acid ester monomer units; 
 2) 0.01 to less than 1 parts by weight of an acid functional monomer units; 
 3) 0 to 25 parts by weight of a second, non-acid functional, polar monomer units; 
 4) 0 to 5 parts vinyl monomer units, and 
   b) a second component comprising at least one free-radically polymerizable solvent monomer, and   c) a polyfunctional aziridine crosslinking agent.   
     
     
         2 . The syrup polymer composition of  claim 1 , wherein the solvent monomer component comprises:
 1) 100 parts by weight of an (meth)acrylic acid ester monomers;   2) 0.01 to less than 1 parts by weight of an acid functional monomers;   3) 0 to 25 parts by weight of a second, non-acid functional, polar monomers; and   4) 0 to 5 parts vinyl monomers.   
     
     
         3 . The syrup polymer composition of  claim 1  comprising 0.005 to 5.0 parts by weight of polyaziridine crosslinking agent, relative to 100 parts of the solute copolymer. 
     
     
         4 . The syrup polymer composition having less than 5 pbw of dead polymer. 
     
     
         5 . The syrup polymer composition of  claim 1  wherein the ratio of the molar equivalents of aziridine groups of the polyfunctional aziridine crosslinking agent to the number molar equivalents of carboxylic acid groups of the solute polymer is between about 1:5 to 1:50. 
     
     
         6 . The composition of  claim 1  wherein the polyfunctional aziridine crosslinking agent comprises a bisamide crosslinking agent. 
     
     
         7 . The composition of  claim 1  wherein the polyaziridine crosslinking agent is of the formula: 
       
         
           
           
               
               
           
         
         wherein 
         R 1  is a (hetero)hydrocarbyl group, 
         R 2  is an H or C 1 -C 4  alkyl group, 
         x is 0, 1 or 2, and 
         y is 2 to 4. 
       
     
     
         8 . The composition of  claim 4  wherein the bisamide crosslinking agent is of the general formula: 
       
         
           
           
               
               
           
         
         Wherein 
         R 3  is a (hetero)hydrocarbyl group; 
         R 2  is an H or C 1 -C 4  alkyl group, 
         x is 0, 1 or 2. 
       
     
     
         9 . The syrup polymer composition of  claim 7  wherein the polyaziridine crosslinking agent is of the formula: 
       
         
           
           
               
               
           
         
         wherein 
         R 4  is a hydrocarbyl group having a valency of y, 
         R 2  is an H or C 1 -C 4  alkyl group, 
         y is at least 2, 
         x is 0, 1 or 2. 
       
     
     
         10 . The syrup polymer composition of  claim 7  wherein the polyaziridine crosslinking agent is of the formula: 
       
         
           
           
               
               
           
         
         wherein 
         R 4  is a hydrocarbyl group having a valency of y, 
         R 2  is an H or C 1 -C 4  alkyl group, 
         y is at least 2, 
         x is 0, 1 or 2; and 
         each of a and b are independently 0, 1 or 2. 
       
     
     
         11 . The syrup polymer composition of  claim 1  wherein the solute copolymer comprises 0.1 to less than 1 parts by weight acid functional monomer units, based on 100 parts of an (meth)acrylic acid ester. 
     
     
         12 . The syrup polymer composition of  claim 1  further comprising 0.01 to 5 parts of a multifunctional (meth)acrylate crosslinking agent based on 100 parts total monomers. 
     
     
         13 . A process for preparing an pre-adhesive copolymer composition comprising:
 a) providing a syrup polymer composition comprising:
 1) a first component solute acid functional (meth)acrylate copolymer, 
 2) a second component comprising at least one free-radically polymerizable solvent monomer comprising an acid functional monomer, and 
 3) a polyfunctional aziridine crosslinking agent; 
   b) wherein the component of the syrup polymer composition are combined for a time, and a temperature sufficient to react, and   c) adding additional acid functional monomers to a total of up to 15 parts.   
     
     
         14 . The process of  claim 13  wherein said first component solute acid functional (meth)acrylate copolymer comprises:
 a) 100 parts by weight of an (meth)acrylic acid ester monomer units; 
 b) 0.01 to less than 10 parts by weight of an acid functional monomer units; 
 c) 0 to 10 parts by weight of a second, non-acid functional, polar monomer units; and 
 d) 0 to 5 parts vinyl monomer units. 
 
     
     
         15 . The process of  claim 13  wherein said first component solute acid functional (meth)acrylate copolymer comprises 0.01 to less than 5 parts by weight of an acid functional monomer units. 
     
     
         16 . The process of  claim 13  wherein said first component solute acid functional (meth)acrylate copolymer comprises 0.1 to less than 1 parts by weight of an acid functional monomer units. 
     
     
         17 . The process of  claim 13  wherein the solvent monomer component comprises 0.01 to less than 15 parts by weight of an acid functional monomers. 
     
     
         18 . The process of  claim 13  comprising 0.005 to 5.0 parts by weight of polyaziridine crosslinking agent, relative to 100 parts of the solute copolymer. 
     
     
         19 . The process of  claim 13  having less than 5 pbw of dead polymer after step b). 
     
     
         20 . The process of  claim 13  wherein the ratio of the molar equivalents of aziridine groups of the polyfunctional aziridine crosslinking agent to the number molar equivalents of carboxylic acid groups of the solute polymer is between about 1:5 to 1:50. 
     
     
         21 . The process of  claim 13  wherein the solvent monomer component comprises:
 a) 100 parts by weight of an (meth)acrylic acid ester monomers; 
 b) 0.01 to less than 5 parts by weight of an acid functional monomers; 
 c) 0 to 25 parts by weight of a second, non-acid functional, polar monomers; and 
 d) 0 to 5 parts vinyl monomers. 
 
     
     
         22 . The process of  claim 13  wherein the polyaziridine crosslinking agent is of the formula: 
       
         
           
           
               
               
           
         
         wherein 
         R 1  is a (hetero)hydrocarbyl group, 
         R 2  is an H or C 1 -C 4  alkyl group, 
         x is 0, 1 or 2, and 
         y is 2 to 4. 
       
     
     
         23 . The process of  claim 13  wherein the bisamide crosslinking agent is of the general formula: 
       
         
           
           
               
               
           
         
         Wherein 
         R 3  is a (hetero)hydrocarbyl group; 
         R 2  is an H or C 1 -C 4  alkyl group, 
         x is 0, 1 or 2. 
       
     
     
         24 . The process of  claim 13  wherein the polyaziridine crosslinking agent is of the formula: 
       
         
           
           
               
               
           
         
         wherein 
         R 4  is a hydrocarbyl group having a valency of y, 
         R 2  is an H or C 1 -C 4  alkyl group, 
         y is at least 2, 
         x is 0, 1 or 2. 
       
     
     
         25 . The process of  claim 13  wherein the polyaziridine crosslinking agent is of the formula: 
       
         
           
           
               
               
           
         
         wherein 
         R 4  is a hydrocarbyl group having a valency of y, 
         R 2  is an H or C 1 -C 4  alkyl group, 
         y is at least 2, 
         x is 0, 1 or 2; and 
         each of a and b are independently 0, 1 or 2.