摘要
研究了非晶态及双轴拉伸聚2,6萘二甲酸乙二酯的钴-60γ-辐射结构效应,总剂量在5×10~2Mrad范围内。用短路热释电手段测定了平均陷阱深度随辐射剂量的变化,揭示了局域陷阱深度与分子链结构,聚集态结构的关系。
The γ-irradiation effect on the structure of molecular chains and supermolecular structure of polyethylene naphthalate (PEN) was investigated. The tolal dose was ranged over 500Mrad. No yγ-irradiation induced crystallization was observed in the amorphous PEN, while the crystallinity of biaxial stretched one decreases with increment of doses. The weight average and number average moleculer weight determination indicated the deg- radation of molecular chains at dose below 400Mrad. Further increment of MW images molecu- lar rearrangment strenghting of intermolecular action at higher doses. It was observed that the mean trap level obtained by means of short-circuit Thermally Stimulated Current measurements at two heating rates, considerably sensitive to γ-irradiation. Experimental results clearly show that the degradation of molecular chains causes shallowing of trap levels, while factors strenghting the intermolecular action including increment of relative content of crystalline region and closslinking provide deeper one.
基金
国家自然科学基金
