环氧树脂的γ射线辐照损伤机理研究

Study on the damage mechanism for epoxy resin under gamma irradiation

采用弯曲性能测试,动态热机械分析和X射线光电子能谱分析研究了γ辐照对环氧树脂性能的影响,并分析了辐照损伤机理。结果表明:辐照会使得环氧树脂中键能较弱的C-N和C-O断裂,断裂形成的自由基再重组生成新C-C键,从而发生进一步交联。低剂量辐照下,材料的弯曲强度增大了5 MPa,玻璃化转变温度提高6℃。随着辐照剂量的继续增加,辐照降解加剧,弯曲强度和玻璃化转变温度都有所下降,但仍高于未辐照样品。因而当辐照剂量小于10 k Gy时,环氧树脂的辐照交联效应大于降解效应。

The effect of y irradiation on the properties of epoxy resin was investigated by using flexural strength testing, dynamic mechanical thermal analysis and X-ray photoelectron spectroscopy and the mechanism of radiation damage was analyzed.The results showed that weak bonds （C-N,C-O） were fractured under the radiation. The free radicals were formed and transformed into new C- C by reeombining and that led to the further cross-linking. The flexnral strength was increased by 5 MPa and the glass transition temperature was increased by 6 ~C under the low dose irradiation. With the further increasing of irradiation dose, the irradiation degradation was aggravated, so the flexural strength and the glass transition temperature were decreased, but still higher than unirradiated samples. Therefore, when the irradiation dose was less than 10 kGy, the cross-linking effect under radiation was greater than the degradation effect for epoxy resin.