Action of sulphur dioxide on block copolymers containing polybutadiene and polydimethylsiloxane

Using different physicochemical techniques the authors have studied the change with time in the properties of poly-(arylate butadiene), poly-(arylenesulphonoxide-butadiene) and poly-(arylate-dimethylsiloxane) block copolymers in air and a medium of of sulphur dioxide. It was found that on exposure to SO2 in the block copolymers irreversible chemical changes take place leading in the case of the polybutadiene-containing copolymers to the crosslinking of the macromolecules at the double bonds and increase in the strength properties of the film samples and in the case of poly-(arylate dimethylsiloxane) to splitting of the siloxane bonds and disruption of the samples. The moisture content of the sulphur dioxide had no appreciable influence on the character of change in the properties of the block copolymers studied.