γ‐Radiolysis of ketone polymers. II. γ‐Irradiation of styrene–methyl vinyl ketone copolymers

Abstract

Abstractγ‐Radiolysis of copolymers of styrene and methyl vinyl ketone shows that the introduction of pendant carbonyl groups markedly increases the G(s) value as compared to the homopolymer of styrene. The G(x) value is only slightly affected. These efficiencies are determined by employing an established statistical theory for random crosslinking and scission coupled with gel‐permeation chromatography as the analytical tool required to follow the changes in the MWD of polymers. Also the G(H2) values are unaltered by the introduction of carbonyl groups in polystyrene. These results are in marked contrast to the effects of carbonyl groups in polyethylene when subjected to γ‐radiolysis and can be attributed to the protective role played by the aromatic phenyl groups in polystyrene.