Method of making compositions from vinyl aromatic resins and rubbery copolymers of styrene and butadiene

Claim 1

IN A METHOD OF MAKING A THERMOSPLASTIC COMPOSITION CONTAINING A POLYMERIZED MONOVINYL AROMATIC HYDROCARBON AND A RUBBERY ELASTOMER INTIMATELY INCORPORATED WITH ONE ANOTHER, WHEREIN A NORMALLY SOLID ALKENYL AROMATIC RESIN AND A RUBBERY ELASTOMER ARE BLENDED BY HEAT-PLASTIFYING AND MECHANICALLY WORKING THE COMPONENTS INTO A UNIFORM MASS AT ELEVATED TEMPERATURES AND SAID HEATPLASTIFIED MASS IS THEREAFTER MECHANICALLY WORKED IN ADMIXTURE WITH A SMALL AMOUNT OF A LIQUID PLASTICIZER AND AN ORGANIC PERIOXIDE, THE STEPS WHICH CONSIST IN BLENDING A NORMALLY SOLID THERMOPLASTIC VINYL AROMATIC RESIN (A) CONSISTING OF AT LEAST ONE POLYMERIZED MONOVINYL AROMATIC HYDROCARBON OF THE NENZENE SERIES AND A RUBBERY COPOLYMER HAS A GEL CONTENT CORRESPONDING TO FROM 70 BUTADIENE AND FROM 60 TO 15 PERCENT OF STYRENE, WHICH COPOLYMER HAS A GEL CONTENT CORRESPONDING TO FROM 70 TO 95 PERCENT BY WEIGHT OF THE COPOLYMER, INTO HEATPLASTIFIED MASS AT TEMPERATURES BETWEEN 140* AND 280*C. IN PROPORTIONS SUCH THAT THE MASS CONTAINS FROM 2 TO 12 PERCENT BY WEIGHT OF CHEMICALLY COMBINED BUTADIENE, BASED ON THE SUN OF THE WEIGHTS OF (A) AND (B) AND THEREAFTER MECHANICALLY WORKING SAID HEAT-PLASTIFIED MAS INTO INTIMATE ADMIXTURE WITH FROM 0.05 TO 5 PERCENT BY WEIGHT OF A LIQUID PLASTICIZER HAVING A BOILING POINT ABOVE 200*C. AND FROM 0.01 TO 0.25 PERCENT BY WEIGHT OF AN ORGANIC TERTIARY HYDROPEROXIDE AT TEMPERATURES BETWEEN 180* AND 280*C.