Patent ID: 9556284
Date: 2017-01-31
CPC Classifications: C08F,C08L,Y10T

Claim:
1. A multi-stage emulsion polymer comprising (a) 90 to 99.5 wt. % of a first polymer, based on total weight of the first polymer and a reinforcing polymer, wherein the first polymer is formed from at least one ethylenically unsaturated monomer, and has a Tg of less than −20° C., and is polymerized in the presence of 3 to 12 mmoles of chain transfer agent per kg of monomers in the first polymer and is optionally polymerized in the presence of a low molecular weight polymeric component; (b) 0.5 to 10 wt. % of the reinforcing polymer based on total weight of the first polymer and the reinforcing polymer, wherein the reinforcing polymer is formed from 10 to 100 wt. %, based on total weight of the reinforcing polymer, of monomers having two or more alpha, beta-ethylenically unsaturated groups wherein the monomers used to form the reinforcing polymer are dispersed in the first polymer and swell the first polymer prior to polymerization of the monomers used to form the reinforcing polymer and (c) a tackifier having a softening point of 70° C. or higher.