Retardation of thermal degradation of PMMA and PVC by C60

Investigations were made on the effects of C-60 upon the rate of depolymerization of PMMA films during the thermal degradation in vacuo at 300 and 332 degrees C by thermogravimetric method and upon the rates of dehydrochlorination of PVC during the thermal degradation in vacuo with continuous and effective removal of HCl and in the presence of volatile products at 200 degrees C. It was shown that C-60 retards the thermal depolymerization of PMMA and the autocatalytic thermal dehydrochlorination of PVC in the presence of HCl and does not decrease the rate of PVC nonautocatalytic degradation with removal of HCl. The suggestion was made that the retarding effect of C-60 is connected with its interaction with macroradicals, which generate in the thermal degradation of PMMA and PVC, with formation of less active compounds. In the case of PVC, there is the probability of interaction of C-60 with chlorine atoms too. (C) 1997 Elsevier Science Ltd.