Epoxy-modified vinyl chloride-vinyl ester copolymer solid resin

Abstract

A process for the preparation of epoxy-modified vinyl chloride-vinyl ester copolymers in the form of the solid resins involves aqueous, free radical polymerization of a mixture comprising a) from 50 to 90% by weight of vinyl chloride, b) from 5 to 25% by weight of epoxide-containing vinyl monomers and c) from 5 to 25% by weight of one or more vinyl esters of straight-chain or branched alkylcarboxylic acids having 1 to 18 carbon atoms, d) from 0 to 40% by weight of further comonomers copolymerizable with a), b) and c), the data in % by weight summing to 100% by weight, and subsequent drying of the aqueous dispersions obtained thereby, polymerization being effected by means of suspension polymerization in the presence of aldehyde regulators.

1 . A process for the preparation of epoxy-modified vinyl chloride-vinyl ester copolymers in the form of solid resin, comprising free radically polymerizing a mixture comprising 
 a) from 50 to 90 percent by weight of vinyl chloride,    b) from 5 to 25 percent by weight of one or more epoxide-containing vinyl monomers and    c) from 5 to 25 percent by weight of one or more vinyl esters of straight-chain or branched alkylcarboxylic acids having from 1 to 18 carbon atoms,    d) from 0 to 40 percent by weight of further comonomers copolymerizable with a), b) and c), the percents by weight of a), b), c), and d) totalling 100% by weight,    and subsequently drying an aqueous dispersion obtained thereby, wherein said polymerizing is effected by means of suspension polymerization in the presence of one or more aldehyde regulators.    
     
     
         2 . The process of  claim 1 , wherein from 5 to 15% by weight of epoxide-containing vinyl monomers are polymerized.  
     
     
         3 . The process of  claim 1 , whererin one or more epoxide-containing vinyl monomers selected from the group consisting of methyl glycidyl methacrylate, methyl glycidyl acrylate, allyl glycidyl ether, allylphenol glycidyl ether and glycidyl methacrylate are copolymerized as comonomers b).  
     
     
         4 . The process of  claim 1 , wherein one or more vinyl esters selected from the group consisting of vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate, 1-methyl vinyl acetate, vinyl pivalate and vinyl esters of α-branched monocarboxylic acids having 9 to 13 carbon atoms, are copolymerized as comonomers c), optionally in combination with one or more comonomers selected from the group consisting of acrylic acid, methacrylic acid, fumaric acid, itaconic acid, crotonic acid, maleic acid and maleic anhydride.  
     
     
         5 . The process of  claim 1 , wherein from 0.001 to 0.1% by weight of ascorbic acid and/or isoascorbic acid, based on the total weight of the comonomers, are added during or after the polymerization, and optionally from 0.001 to 0.1% by weight of citric acid, based on the total weight of the comonomers, is also added in addition to the ascorbic acid and/or isoascorbic acid.  
     
     
         6 . The process of  claim 5  wherein citric acid is added.  
     
     
         7 . The process of  claim 1 , wherein polymerization takes place in the presence of from 0.02 to 10% by weight, based on the monomers to be polymerized, of regulators.  
     
     
         8 . The process of  claim 1 , wherein polymerization is effected in the presence of propionaldehyde.  
     
     
         9 . A coating binder, comprising the product produced by the process of  claim 1 .  
     
     
         10 . A process for adhesive bonding, comprising applying an adhesive comprising the product produced by the process of  claim 1  to at least one substrate to be bonded to a second substrate, and contacting said substrates together.  
     
     
         11 . The process of claim  19 , wherein one of said substrates comprises a security feature.