Modified styrene-maleic acid copolymer and use thereof

Abstract

The present invention relates to a modified styrene-maleic acid copolymer obtained by reacting a carboxylic acid group in a styrene-maleic acid copolymer with a halogen and/or epoxy compound. The modified styrene-maleic acid copolymer is useful as a low profile additive for a thermosetting resin, a water-absorbing material, etc.

1 . A modified styrene-maleic acid copolymer, which is produced by a process comprising reacting a carboxylic acid salt in a styrene-maleic acid copolymer containing a structural unit represented by the formula (1): 
     
       
         
         
             
             
         
       
     
     wherein A is a metal element, m is a number from 1 to 3, n is a number from 3 to 300, and both ends are hydrogen atoms, with the proviso that when A is a di- or more valent metal element, the metal element may form a salt with plural carboxy groups, which are not limited to those in the same molecule, with a compound containing at least two halogens. 
   
   
       2 . The modified styrene-maleic acid copolymer according to  claim 1 , wherein the compound containing at least two halogens is 1,3-dichloro-2-propanol. 
   
   
       3 . The modified styrene-maleic acid copolymer according to  claim 1 , which is produced by a process comprising reacting a carboxylic acid salt in a styrene-maleic acid copolymer with a compound containing at least two halogens such that the amount of the halogen in the compound is ⅘ or less equivalent relative to the amount of the carboxylic acid salt in the copolymer. 
   
   
       4 . The modified styrene-maleic acid copolymer according to  claim 1 , wherein the styrene-maleic acid copolymer to be modified is produced by a process comprising decomposing a thermosetting resin comprising a polyester and its crosslinking moiety with subcritical water.