摘要 |
An improved tough, transparent polymer alloy comprised of 90 to 20 weight percent of a brittle polymer with a weight average molecular weight greater than 180,000; 0 to 60 weight percent of a rubbery polymer; 0 to 80 weight percent of a ductile polymer; and between greater than 0.4, i.e. between 0.5 and 3 weight percent of a plasticizer, i.e., mineral oil which resides in th e brittle polymer. The brittle polymer can have molecular weights between 220,000 and 300,000, and may be as high as 400,000. In one of the preferred embodiments the brittle polymer is a copolymer of styrene and methyl methacrylate which copolymer ranges between 50 and 55 weight percent, the rubbery polymer is 0 weight percent, the ductile polymer is a styrene butadiene block copolymer ranging between 45 and 50 weight percent, and the mineral oil is 1.5 weight percent. Notched IZOD impact strength ranges betwe en 1.0 to 6.0 ft-lb./in., preferably between 2.0 and 4.5 ft-lb./in. The haze ca n be less than 1.5% or it can be between 1 and 4%.
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