Inventors:
Robert M. Myers - Philadelphia PA
David L. Dunkelberger - Levittown PA
Daniel T. Carty - Willingboro NJ
Assignee:
Rohm and Haas Company - Philadelphia PA
International Classification:
C08F25702, C08F26506, C08F29102, C08F29106
Abstract:
A three-stage, sequentially produced graft polymer comprises (A) a non-rubbery, hard first stage polymer formed by the sequential polymerization of a monomer charge of 50 to 100 weight percent of a vinylaromatic compound, 0 to 50 weight percent of a different monovinylidene monomer interpolymerizable therewith, and 0 to 10 weight percent of a polyfunctional crosslinking monomer based on the weight of the monomer charge; (B) a second stage rubbery polymer formed by sequentially polymerizing in the presence of the hard polymer Stage (A) a second monomer charge of 50 to 100 weight percent of butadiene, isoprene, chloroprene, an alkyl acrylate or mixtures thereof wherein the alkyl group of the alkyl acrylate has about 3 to 8 carbon atoms, 0 to 50 weight percent of a monovinylidene monomer interpolymerizable therewith, and 0 to 10 weight percent of a polyfunctional crosslinking agent; and (C) a third stage polymer formed by sequentially polymerizing in the presence of the Stage (A) and Stage (B) polymer product a monomer charge of 50 to 100 weight percent of an alkyl methacrylate wherein the alkyl group has about 1 to 4 carbon atoms, 0 to 50 weight percent of a vinylidene monomer interpolymerizable therewith, and 0 to 10 weight percent of a polyfunctional crosslinking monomer, and/or 0 to 1. 0 weight percent of an alkyl mercaptan of 3 to 12 carbon atoms. Preferably the polymer is used as a modifier for vinyl halide polymers.