PHOTODEGRADATION OF CHAIN HALOGENATED POLYSTYRENE - POLY (C-CHLORO AND C-BROMOSTYRENE)S

The photodegradation of films of poly chain-chlorostyrene (PCCS) and p oly chain-bromostyrene (PCBS) achieved by exposure to 254-nm radiation under dynamic vacuum was studied. The minor gaseous products obtained were hydrogen halides and monomer. The polymers were investigated by ir, gel permeation chromatography, and microanalysis. Both polymers un dergo main chain scission. The ir spectra of the degraded polymers ind icate the presence of unsaturated species. An initial alpha-carbon-hal ogen bond fission is required to account for the present reaction prod ucts. Possible mechanism of the various photoreactions are discussed.