抄録
In this study, photo-and thermal-degradation behaviors of high density polyethylene (HDPE) with/without polymethylphenylsilane (PMPS) were investigated. There is a tendency that the modulus of HDPE with/without PMPS exposed to UV irradiation increased with exposure time, although the elongation at break decreased with exposure time. In particular, the ductile-brittle transition occurs earlier by the addition of PMPS. This result suggests that PMPS can accelerate photo-degradation of HDPE. As for the thermal-degradation, the oxidation induction time (OIT) of HDPE with PMPS is also shorter than that of neat one. Moreover, the activation energy of the oxidation of HDPE decreased with the PMPS content, indicating that PMPS also accelerates the thermal-degradation. Although the mechanism to accelerate the photo-and thermal-degradation of HDPE has not been cleared yet, it can be deduced that the pro-oxidant process caused by accelerating autoxidation with silyl radical generated by PMPS during UV irradiation and/or heattreatment occurred in HDPE.
