电子束辐射固化环氧树脂的动态力学分析——辐射剂量、引发剂用量及热处理的影响

DYNAMIC MECHANICAL ANALYSIS OF ELECTRON BEAM CURED EPOXY RESINS --INFLUENCE OF RADIATION DOSAGE, INITIATOR DOSAGE AND HEAT TREATMENT

对电子束辐射固化的环氧树脂进行了动态力学分析。通过对不同样品凝胶含量、内耗 tanδ及动态模量变化趋势的研究 ,得到电子束辐射剂量、引发剂用量和热处理等因素对环氧树脂辐射交联反应的影响规律。辐射剂量的增加使环氧树脂凝胶含量、玻璃化温度 Tg 及高温模量有所增加 ,但增长幅度在高辐射剂量下逐渐变小 ,且树脂交联体系的不均匀性随辐射剂量增大而有所增加。低剂量辐射下 ,环氧树脂固化物的玻璃化温度及高温模量随引发剂用量增加而增大 ,高辐射剂量下 ,引发剂的用量存在最佳值。经过热处理后辐射样品的交联程度得到提高 ,当热处理温度超过引发剂的热分解温度时 。

Dynamic mechanical analyses of electron beam (EB)-cured epoxy resin are made. Through the research on the variation regularity of the gel fraction, damping factor and dynamic modulus for different samples, the influences of EB radiation dosage, initiator dosage and heating treatment on the radiation curing reaction of epoxy resin were obtained. The gel fraction, glass transition temperature and high temperature modulus of the cured epoxy resin increase with the rising of radiation dosage, and the increased amplitude is decrescent at high radiation dosage. The inhomogeneity degree of cross-linked structure is enhanced with the increase of radiation dosage. In low radiation dosage, the glass transition temperature and high temperature modulus of the cured epoxy resin increase with the increase of initiator dosage. But when a high radiation dosage is used, the optimal dosage of the initiator appears. When the EB-cured epoxy resin is heated, the cross-linking extent is enhanced. But when the temperature of heating treatment exceeds the thermal decomposition temperature of the initiator, the local cross-linking network formed from the thermal curing reaction can exist in the resin system.