engleski

Influence of Thermal and UV Radiation on Polystyrene Structure

The glass transition temperatures have been measured on ataction polystyrene after termo-oxidative and photo-oxidative degradation. For comparision, DSC patterns of degraded samples were made. The DSC patterns were found to be quite sensitive to small changes in polymer structure and types of linkage. Examination of the date shows that Tg values of degraded samples are shifted to lower values, and several Tg transitions have occurred as the degradation time is proceeding. The X-ray diffraction pattern obtained from a specimen of polystyrene is characteristic of that of an amorphous material, viz. it consists of broad and diffuse haloes. The study of the scattering from polystyrene, as a function of temperature and UV irradiation, has revealed a change in location, shape and intesity of the scattering pattern. It is shown that these results can be interpreted in terms of definite structural changes which take place during polystyrene degradation.

degradation; polystyrene

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