Photodehydrochlorination of carbon monoxide–vinyl chloride copolymer

Abstract

In order to examine effect of the carbonyl group in carbon monoxide–vinyl chloride copolymer, poly(CO–VC), photoirradiation with a high‐pressure mercury lamp on the copolymer was carried out. Poly(CO–VC) had a rate of dehydrochlorination three times that of PVC, and the reaction involved a decrease in chlorine content. Also there was a marked change in the ultraviolet spectra of the photoirradiated films. However, no pronounced change of molecular weight was observed, but a change in Rf in TLC was observed clearly. These facts confirmed that photoirradiation of poly(CO–VC) produced a structural change by dehydrochlorination without serious decrease of molecular weight. In addition, photodehydrochlorination of the copolymer or PVC film was followed kinetically, and after ozonolysis of the dehydrochlorinated polymers, the number‐average molecular weights were measured. From the results of degree of dehydrochlorination and molecular weight, the number average of conjugated double bonds or carbonyl groups was estimated. A mechanism for dehydrochlorination process by photo‐irradiation is suggested.

Photodegradation of carbon monoxide–styrene copolymer in benzene and formation of block copolymer with methyl methacrylate

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Effect of tetraphenylphenyl‐modified fumed silica on silicone rubber radiation resistance

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