Pyrolysis of polymeric hydrocarbons in the presence of derivatives of 2-mercaptobenzothiazole

Polypropylene, polyisobutylene, polystyrene and poly(a-methylstyrene) were pyrolyzed in an inert atmosphere in sealed Pyrex tubes , in a tube-furnace and with a platinum wire filament. The temperature ranged from 370 to 525[degrees]C. Both the tube-furnace and the platinum wire filament were connected to a gas chromatograph. Controlled amounts of 2-mercaptobenzothiazole, 2-bis-benzothiazyl disulfide, K-tert.-butylbenzothiazole-2-sulfensmide and N-cyclohexylbenzothiazole-2-sulfenamide did not affect the decomposition of the polymeric hydrocarbons when the pyrolysis took place in the tube-furnace or platinum wire filament. In the sealed tube technique, there was a decrease in the ratio of the relative concentrations of the unsaturated products, and the corresponding saturated products as the percent of the derivatives of 2-mercaptobenzothiazole admixed with polymers increased. The presence of derivatives of 2-mercaptobenzothiazole do appear to affect the mechanism of degradation of polymeric hydrocarbons when pyrolyzed in a sealed tube.