CAJ | 학술논문

为了探求聚乙烯（PE）辐射致色的主要原因，用测色色差计测定了高密度聚乙烯(HDPE)和低密度聚乙烯(LDPE)在不同剂量辐照时及其在辐照后黄度的变化，并用ESR谱仪和紫外可见光谱仪测定了辐照时自由基、共轭双键的生成，辐照后存放时自由基的衰减和共轭双键的变化。结果表明，HDPE比LDPE更容易辐射致色，经不同剂量辐照后的PE的黄度均随存放时间增加而降低，最后趋于稳定。辐照时自由基的生成以及辐照后存放时自由基的衰减规律和PE黄度的变化非常相似，但辐照时共轭双键的生成以及辐照后的变化与PE黄度的变化不同，PE的辐射致色主要是由生成的陷落自由基引起的。
위료탐구취을희（PE）복사치색적주요원인，용측색색차계측정료고밀도취을희(HDPE)화저밀도취을희(LDPE)재불동제량복조시급기재복조후황도적변화，병용ESR보의화자외가견광보의측정료복조시자유기、공액쌍건적생성，복조후존방시자유기적쇠감화공액쌍건적변화。결과표명，HDPE비LDPE경용역복사치색，경불동제량복조후적PE적황도균수존방시간증가이강저，최후추우은정。복조시자유기적생성이급복조후존방시자유기적쇠감규률화PE황도적변화비상상사，단복조시공액쌍건적생성이급복조후적변화여PE황도적변화불동，PE적복사치색주요시유생성적함락자유기인기적。
In order to find the major reason for the radiation discoloration of PE, the changes of yellow index (YI) of HDPE and LDPE under γ irradiation in air or N2 and after irradiation are measured using colorimeter. The growth and decay of alkyl free radical formed in HDPE and LDPE, and the change of the absorbance of conjugated double bonds formed in PE are measured using ESR and UV-Visible spectrometer.The YI of HDPE is higher than that of LDPE at the same radiation dose. The YI of PE irradiated in air is higher than that of PE irradiated in N2 at the same radiation dose. The YI of PE irradiated different dose decreases with post-irradiation storage time firstly, up to a certain time, it becomes stable. It is found that the formation and decay of free radicals is very similar to that of the change of YI, whereas, the change of the absorbance of conjugated double bonds formed in PE is different to the change of YI. The results are discussed, it is believed that the major reason for the radiation discoloration is the formation of trapped free radicals.