| 摘要 |
A thermoplastic composition comprises a polycarbonate that is not aryl carboxylate end-capped, and an aryl carboxylate end-capped polycarbonate of formula: <?in-line-formulae description="In-line Formulae" end="lead"?>Ar<SUP>1</SUP>-C(O)-O-(-L-)<SUB>m</SUB>-O-C(O)-A<SUP>1</SUP><?in-line-formulae description="In-line Formulae" end="tail"?> wherein each Ar<SUP>1 </SUP>is independently an aryl group, -(-L-)<SUB>m</SUB>- is a polycarbonate linking group with m units of linking unit L, and m is at least one; wherein the aryl carboxylate end-capped polycarbonate has aryl carboxylate end groups present in the thermoplastic composition in an amount of 0.01 to 500 mmol/Kg based on the combined weights of the polycarbonate that is not aryl carboxylate end-capped, and the aryl carboxylate end-capped polycarbonate, and wherein a molded article having a thickness of 3.2±0.12 millimeters and consisting of the aryl carboxylate end-capped polycarbonate, the polycarbonate, and less than or equal to 1.0 percent total weight of aliphatic diol, a mold-release agent, and an antioxidant has, after exposure to a total gamma radiation dose of 81 kGy and when measured according to ASTM D1925-70, an increase in yellowness index (dYI) of less than or equal to 24.5, when compared to the unexposed molded article. A method for preparing the aryl carboxylate end-capped polycarbonate that is not aryl carboxylate end-capped, and thermoplastic composition, an article prepared from the thermoplastic composition, are also disclosed.
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