PHOTODEGRADATION OF HIGH POLYMERS. PART V. PHOTOLYSIS OF POLY(ALKYLENE POLYSULFIDES) IN VACUUM.

The rates of weight loss of several polyalkylene polysulfides during exposure to a simulated space environment were measured and compared to the rates of weight loss of several nonsulfur containing polymers. The products of degradation of polymethylene disulfide and tetrasulfide and polyethylene disulfide and tetrasulfide were identified and gaseous products were quantitatively measured. The major products of degradation were hydrogen sulfide, carbon monosulfide which polymerizes on surfaces within the exposure cell, and, for the methylene polymers, carbon disulfide. The tetrasulfide polymers deposited a rubbery film on the walls of the exposure cell which was spectroscopically identical to exposed polyalkylene tetrasulfide. A mechanism of degradation compatible with these results is suggested. Author