Three-stage polymer particle

Abstract

Provided is polymer particle comprising (a) 40% to 85% by weight, based on the dry weight of the polymer particle, a core polymer having Tg of −35° C. or lower; (b) 15% to 50% by weight, based on the dry weight of the polymer particle, an intermediate polymer having Tg that is 20° C. or lower and that is higher than the Tg of the core polymer by 10° C. or more; (c) 5% to 30% by weight, based on the dry weight of the polymer particle, a shell polymer having Tg of 50° C. or higher; wherein the shell polymer comprises polymerized units of all vinyl aromatic monomers in an amount of 1% or less, by weight based on the weight of the shell polymer.

Dependencies are inferred from the claim text.