Production of lifetime controlled plastics: copolymers of styrene and substituted butadienes

摘要

This work was directed to the study of the UV radiation effects on samples of polystyrene (PS) and copolymers of styrene with different proportions of 2-substituted-1,3-butadienes, in the presence of air and in solution, aiming at the optimisation of the degradation of the PS when exposed to the natural environment. Polymers were prepared by free-radical polymerization in solution, using azo-bis-isobutyronitrile as initiator, resulting in an average molecular weight, M_W of about 30.0 kg/mol for the homo- and copolymers. The polymers were separated and characterized by infrared spectroscopy, elemental analysis, light scattering and gel permeation chromatography. The degradation rates were directly related to the increase in the comonomer contents of the polymers.