Patent ID: 8217109
Filing Date: 2012-07-10
Classification: C04B,C08F

Abstract:
1. A process for the production of a protective-colloid-stabilized base polymer in the form of a water-redispersible powder, said polymer comprising a homo- or copolymer of one or more monomers selected from the group consisting of vinyl esters of optionally branched alkyl carboxylic acids having from 1 to 15 carbon atoms, (meth)acrylic esters of alcohols having from 1 to 15 carbon atoms, vinylaromatics, olefins, dienes, and vinyl halides wherein said polymer is prepared by emulsion polymerization or suspension polymerization in the presence of a protective-colloid and drying of the polymer dispersion thus obtained after addition of further protective colloid, wherein partially hydrolyzed vinyl acetate-ethylene copolymers with an ethylene content of from 1 to 15 mol %, with a degree of hydrolysis DH of the vinyl acetate units of 80 mol %<DH<95 mol %, and with a Höppler viscosity, in 4% by weight aqueous solution, of from 2 to 30 mPas, as measured by the Höppler method at 20° C., according to DIN 53015, are used as protective colloids.