Ternary polymer blends containing a polyetherimide, a polyphthalate carbonate, and rubber modified vinyl aromatic polymer

A ternary polymer blend comprising in admixture (a) a polyetherimide, (b) a rubber modified vinyl aromatic polymer, and (c) a polyphthalate carbonate prepared from a dihydric phenol, a carbonate precursor, a terephthalic acid or ester-forming derivative thereof, an isophthalic acid or ester-forming derivative thereof, said polyphthalate carbonate having from about 70 to 95 weight percent ester content and a range of terephthalate groups ranging from about 2 to about 15 percent of the ester content, wherein the rubber modified vinyl aromatic polymer is selected from the group consisting of methyl methacrylate-butadiene-styrene, styrene-ethylene-butylene-styrene, acrylonitrile-butadiene-styrene and high impact polystyrene.