CR-39塑料在中子辐照前后结构变化的研究

Structure change of CR-39 after neutron irradiation

本文通过化学方法对经中子辐照处理前后的CR-39塑料中残存碳-碳双键含量进行测定,并用GPC法测定了碱性水解后水解产物聚烯丙醇链的分子量及其分布。辐照前后的碳-碳双键的百分含量分别为0.83％和0.66％,水解产物聚烯丙醇链辐照前的=1.87×10~3,=7.39×10~5;辐照后的=1.79×10~3,=12.2×10~3。实验结果表明辐照可以引发CR-39中的碳-碳双键;辐射交联反应主要发生在烯丙基链,辐射裂解反应主要发生在酯键。

Determined were the percentage of C=C double bond in CR-39, the molecular weight and the distribution of polyallyl chains obtained by hydrolysis of the plastic. C=C(%) is 0.83% and 0.66% before and after irradiation, respectively. Mn= l.87×103 and 1.79×103 while Ma,=7.39×103 and 12.2×103 before and after irradiation respectively. The hydrolysis of CR-39 after irradiation is by far faster than before irradiation. These experimental results indicate that irradiation can initiate C=C double bond in CR-39, the racia-tion crosslinking occurs mainly on polyallyl chains and the radiation degradation mainly on diethyleneglycol dicarborate links.