电子束固化环氧树脂的物理特征及其分析

分析了环氧树脂电子束辐射固化的物理特征 ,电子束辐射固化过程受活性中心扩散控制 ,整个固化区域由片层状结构组成 .与电子能量沉积分布相对应 ,环氧树脂辐射固化度的最高值是在一定深度而不是在辐射表面出现 .对电子束辐射环氧树脂体系的固化过程进行了模型解释 ,固化区域大小主要由电子的能量传递范围和浓度决定 ,反应活性中心的扩散作用影响较弱

PHYSICAL CHARACTERISTIC AND ANALYSES OF ELECTRON BEAM CURING IN EPOXY RESINS

In accordance with the trend towards cheap and trouble-free curing techniques,electron beam (EB) curing of composites involves using electron radiation to initiate the polymerization and crosslinking reaction in suitable matrix resins.EB curing technology of composites offers many advantages compared to conventional thermal curing and is an important innovative technology at present.Most variety of epoxy resins has been confirmed to possess radiation reactivity and has already become the chief resin matrix used in EB curable composites.The physical characteristics of epoxy resin systems cured by electron beam radiation were studied.The results of observing the cured areas indicate that EB-cured resins extend layer upon layer around active centers.Whole cured area consists of many lamellar structures.Through the analyses on the changes of curing degree with the radiation depth in the cured samples,it can be found that the gel fraction of cured epoxy resin increases with the rising of radiation dose.A maximum curing degree occurs at a certain depth of resin systems, but not at the top surface.A model interpretation was made for the process of electron beam curing.The dimension of cured areas is dependent on the pervasion power and concentration of high-energy electrons in the resin systems,and the influence of diffusion of reaction active centers is weak.