Patent ID: 9567261
Date: 2017-02-14
CPC Classifications: C04B,C08F,Y10T

Claim:
1. A vinyl ester/ethylene copolymer prepared by emulsion copolymerization of a monomer mixture comprising at least one vinyl ester, ethylene, a stabilizing system comprising polyvinyl alcohol and a free radical redox polymerization initiator system comprising t-butyl hydroperoxide as an oxidizing agent and at least one of a sulfinic acid-based compound as a reducing agent, wherein said monomer mixture comprises from 70 wt % to 95 wt % of said at least one vinyl ester and from 5 wt % to 30 wt % of ethylene based on the total weight of monomers in said mixture and the copolymer has a formaldehyde content of less than 5.0 ppmw as determined by ISO-15173.