HALS对PE辐射致色的影响  

EFFECT OF HALS ON RADIATION DISCOLORATION OF PE

作　　者：汪辉亮[1] 王春[1] 陈文琇[1] 

机构地区：[1]北京师范大学化学系,北京100875

出　　处：《辐射研究与辐射工艺学报》2001年第2期105-110,共6页Journal of Radiation Research and Radiation Processing

基　　金：北京师范大学青年科学基金资助

摘　　要：研究了受阻胺类光稳定剂 (HALS)对聚乙烯 (PE)辐射致色的影响。发现各种HALS均能减少PE的辐射致色。在辐照剂量低于 10 0kGy时 ,添加五甲基HALS的PE的黄度比添加相应的四甲基HALS的PE的黄度略高 ;而在辐照剂量高于 10 0kGy时 ,结果相反。并且发现 ,在相同的辐照剂量下 ,添加聚合物型HALS的PE的黄度比添加相应的单体型HALS的PE的黄度低一些。还测定了添加HALS的PE在辐照后烷基自由基、羰基的生成。发现 ,在辐照剂量较大时 ,添加TMPM的PE的烷基自由基相对浓度大于添加PMPM的烷基自由基相对浓度。在辐照剂量较低时 ,含五甲基HALS的PE薄膜的羰基指数比含四甲基HALS的PE薄膜的小 ,而在辐照剂量较高时 ,结果相反。The effects of hindered amine light stabilizers (HALS) on the radiation-induced discoloration of polyethylene (PE) are studied by measuring the yellowness index (YI) of PE. It is found that all the HALS used are effective in preventing PE from radiation-induced discoloration. The YI of PE added pentamethyl HALS (PMPM, PPMPM) is a little higher than that of PE added corresponding tetramethyl HALS (TMPM, PTMPM) when radiation dose is lower than 100kGy, but when the radiation dose is higher than 100kGy, the YI of PE added pentamethyl HALS is lower. Pentamethyl HALS is more effective in preventing PE from radiation-induced discoloration when radiation dose is higher. It is also found that polymeric HALS is more effective in preventing PE from radiation-induced discoloration than corresponding monomeric HALS when radiation dose is higher than 200kGy. The formation of alkyl free radical, carbonyl after irradiation is measured. It is found that the relative concentration of free radical formed in PE added TMPM is higher than that of PE added PMPM when radiation dose is relatively high. The carbonyl index of PE containing pentamethyl HALS is less than that of PE containing tetramethyl HALS when radiation is relatively low, but the result is contrary when radiation dose is relatively high. It is believed that HALS prevents PE from radiation-induced discoloration by scavenging free radicals formed in irradiated PE.

关 键 词：聚乙烯 PE 辐射致色 受阻胺类光稳定剂 HALS 黄度 烷基自由基 羰基 辐射剂量 

分 类 号：O631.34[理学—高分子化学] TQ314.245.2[理学—化学]