Method of blending polystyrene and graft copolymer of styrene with butadiene polymer

Claim 1

A PROCESS FOR THE PREPARATION OF POLYSTYRENE RESIN COMPOSITION WHICH PROCESS COMPRISES THE STEPS OF POLYMERIZING A MONOMER SELECTED FROM THE GROUP CONSISTING OF BUTADIENE AND MIXTURES OF BUTADIENE AND STYRENE CONTAINING AT LEAST 50% BUTADIENE IN WATER IN THE PRESENCE OF A FREE RADICAL POLYMERIZATION CATALYST, AND AN EMULSIFYING AGENT TO PRODUCE AN AQUEOUS EMULSION OF A BUTADIENE POLYMER, PRECOAGULATING SAID EMULSION BY ADDITION THERETO OF A COAGULATING AGENT, ADDING MONOMERIC STYRENE TO THE PRE-COAGULATED POLYMER, POLYMERIZING STYRENE IN CONTACT WITH SAID PRE-COAGULATED POLYMER TO FORM A GRAFT COPOLYMER CONTAINING FROM ABOUT 10 TO ABOUT 80 PARTS GRAFTED STYRENE PER 100 PARTS GRAFT COPOLYMER, SEPARATING SAID GRAFT COPOLYMER FROM THE WATER PHASE, ADMIXING SAID SEPARATED GRAFT POLYMER WITH A SOLUTION OF POLYSTYRENE IN AN INERT HYDROCARBON SOLVENT TO FORM A RESIN COMPOSITION CONTAINING FROM ABOUT 5 TO ABOUT 30 PARTS OF SAID GRAFT COPOLYMER PER 100 PARTS OF RESIN AND SEPARATING FROM SAID SOLVENT THE RESIN COMPOSITION SO PREPARED.