聚乙烯膜γ射线辐照生成自由基的ESR研究  

ESR study of radicals in irradiated LDPE and HDPE membranes

作　　者：俎建华[1] 刘新文[1] 周瑞敏[1] 屠铁城[2] 邱士龙[2] 

机构地区：[1]上海大学射线应用研究所,上海201800 [2]中国科学院上海应用物理研究所,上海201800

出　　处：《辐射研究与辐射工艺学报》2005年第3期174-178,共5页Journal of Radiation Research and Radiation Processing

基　　金：国家自然科学基金(50303009)资助

摘　　要：研究了几种类型的聚乙烯膜在不同辐照气氛下生成的自由基的电子自旋共振(ESR)谱。表征了高密度聚乙烯(HDPE)辐照生成的自由基在不同放置温度时的衰减情况,为其预辐照后选择最佳放置时间及放置温度提供依据。辐照剂量在10—100kGy范围内,HDPE膜上自由基的生成量与辐照剂量呈线性关系。在相同的辐照剂量下,HDPE膜自由基的生成量高于低密度聚乙烯(LDPE),所以预辐照接枝以HDPE基膜为好。HDPE膜空气中辐照生成烷基过氧化物的速度受氧扩散量的控制。Electron spin resonance (ESR) method was used for studying radicals generated in low and high density polyethylene (LDPE and HDPE) by gamma ray irradiation. Decay rate of the radicals were determined as a function of storage time at different temperatures, according to which, appropriate storage time and temperature could be chosed for the irradiated polyethylene. Identification and quantitative analysis of radicals originated from different types of polyethylene was done with the PE samples irradiated under ambient or N2 atmosphere. For the relationship between radical concentration and irradiation dose, the results showed a nearly linear increasing of R·, (relative concentration of radicals) with doses in the range of 10-100 kGy. Under the same dose, R· of the HDPE samples was higher than LDPE, and HDPE was chosen for pre-irradiation grafting. In the case of irradiation HDPE under ambient atmosphere, decay rate of R· was dominated by quantity of oxygen diffusing into the HDPE matrix.

关 键 词：聚乙烯 辐照 电子自旋共振 

分 类 号：O631[理学—高分子化学]