Heat stabilized polycarbonate resin

Claim 1

An unpigmented aromatic polycarbonate composition stabilized against heat degradation with (a) a minor amount of a phosphite selected from the group consisting of diaryl hydrogen phosphite, dialkyl hydrogen phosphite and alkyl aryl hydrogen phosphite and mixtures thereof wherein the alkyl portion contains 2-25 carbon atoms and the aryl portion contains 1-3 phenyl rings, and (b) 0.01 - 0.5 weight percent of an epoxy compound selected from the group consisting of: I. derivatives of epoxy ethane represented by the following formula: ##STR3## wherein R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of hydrogen, an alkyl radical of 1-24 carbon atoms, an aryl radical of 6-24 carbon atoms, --CH 2 OR', --CH 2 OCOR', --CH 2 OCOR"COOCH 2 X, CH 2 OR"OCH 2 X wherein R' is selected from the group consisting of an alkyl radical of 1-24 carbon atoms or an aryl radical of 6 to 24 carbon atoms and wherein R" is an alkylene radical of 1-24 carbon atoms and X is an oxirane ring. Ii. derivatives of epoxy cyclohexane represented by the following formula: ##STR4## wherein R 5 through R 12 are independently selected from the group consisting of hydrogen, alkyl radicals of 1-24 carbon atoms, --COOR 13 , --OCOR 13 , --COOR 14 X, --OCOR 14 --COOX wherein R 13 is an alkyl radical of 1-24 carbon atoms and R 14 therein is an alkylene radical of 1-24 carbon atoms and X is an oxirane ring.