Miscible blends of ethylene copolymers with improved temperature resistance

Abstract

The present invention is a composition useful as an impact modifier for polyamide compositions. In one embodiment, impact modifiers of the present invention are ethylene maleic anhydride copolymers having at least 3% maleic anhydride functionality. Compositions comprising copolymers of ethylene and maleic anhydride or its functional equivalents and ethylene copolymers with polar comonomers are disclosed. The compositions provide miscible blends and exhibit improved properties, such as increased temperature resistance and mechanical strength, compared to pure ethylene copolymers with polar comonomers.

1 . A composition comprising: 
 (c) a copolymer obtained from copolymerization of ethylene and maleic anhydride or its functional equivalent, in an amount from about 5 to about 95 weight % of the composition; and    (d) at least one ethylene copolymer obtained from copolymerization of ethylene with a polar monomer wherein said polar comonomer is present in the copolymer in an amount of from 6 to 40 weight %, wherein said copolymer is selected from the group consisting of ethylene/vinyl acetate copolymers, ethylene/alkyl (meth)acrylate copolymers and ethylene/(meth)-acrylate/carbon monoxide terpolymers, in an amount from about 5 to about 95 weight % of the adhesive composition.    
   
   
       2 . The composition of  claim 1  wherein the copolymer of (c) is obtained from copolymerization of ethylene and maleic anhydride.  
   
   
       3 . The composition of  claim 1  wherein the copolymer of (c) is obtained from copolymerization of ethylene and a functional equivalent of maleic anhydride selected from maleic acid and/or salts thereof, maleic acid diesters, maleic acid monoesters, itaconic acid, fumaric acid, fumaric acid monoester, and mixtures of any of these.  
   
   
       4 . The composition of  claim 3  wherein the maleic diesters or monoesters are esters of C 1  to C 4  alcohols.  
   
   
       5 . The composition of claim  4 .wherein the copolymer of (c) is obtained from copolymerization of ethylene and a maleic acid monoester.  
   
   
       6 . The composition of  claim 5  wherein the maleic acid monoester is ethyl hydrogen maleate.  
   
   
       7 . The composition of  claim 1  wherein component (d) is an ethylene/vinyl acetate copolymer.  
   
   
       8 . The composition of  claim 1  wherein component (d) is an ethylene/alkyl (meth)acrylate copolymer.