Patent ID: 6590022
Filing Date: 2003-07-08
Classification: C08F

Abstract:
Process for preparing protective-colloid-stabilized vinlyaromatic-1,3-diene copolymers in the form of their aqueous polymer dispersions or in the form of their water-redispersible powders, by emulsion polymerization of a mixture comprising at least one vinylaromatic monomer and comprising at least one 1,3-diene monomer in the presence of protective colloid and, optionally, drying the resultant polymer dispersions, wherein some of the protective colloid is used as an initial charge and some of the protective colloid is used as a feed, and wherein the weight ratio of protective colloid initially present to monomers initially present is from 0.1:1 to 0.9:1, and wherein from 2 to 90 percent by weight of total protective colloid is used in the initial charge, and the remainder is metered as said feed.