Transparent sheets and containers formed from polycarbonate-polyester blends and formation thereof

A process of forming a sheet which comprises:

• a. uniformly blending a composition comprising about 80 to 97% by weight polyethylene terephthalate having an intrinsic viscosity of above about 0.9 as measured in a mixed solvent of 60 parts by weight phenol and 40 parts by weight tetrachloroethane at 25.degree. C., and a melt viscosity at 525.degree. F. of about 10,000 poises with correspondingly about 20 to 3% by weight of a polycarbonate resin having an intrinsic viscosity of 0.4 to 0.6 as measured in dioxane at 30.degree. C. and a melt viscosity at 500.degree. F. of less than about 50,000 poises, said blending being conducted below the respective melting points of both the polyethylene terephthalate and polycarbonate materials;
• b. extruding said composition at a temperature between about 490.degree. to 530.degree. F. whereby a sheet is obtained;
• and
• c. rapidly cooling the resultant sheet by contact with at least one cooling surface maintained at a surface temperature in the range of about 50.degree. to 160.degree. F. for a period of time not exceeding 15 seconds, whereby a sheet is obtained, being non-oriented having a haze value as determined by ASTM D-1003 of less than about 2% wherein the polyethylene terephthalate portion of the sheet has a degree of crystallinity of less than 5%.