大剂量范围电子束辐照超高分子量聚乙烯纤维结构与性能研究

Study on Structure and Properties of Ultra-High Molecular Weight Polyethylene Fibers Irradiated by Electron Beam in Large Dose Range

采用高能电子束辐照方法获得了一系列从20kGy到1000kGy大剂量辐照范围的超高分子量聚乙烯纤维(UHMWPE fiber)。通过凝胶含量测试和溶胶流变性能测试定性和定量表征了辐照过程的交联和裂解效应,利用差示扫描量热仪(DSC)和X射线衍射仪(XRD)表征了辐照产物的结晶性能,并且利用热机械分析仪(TMA)表征了辐照纤维在高温恒温条件下的热尺寸稳定性。结果表明,高能电子束辐照对于UHMWPE纤维具有交联和裂解两种作用;大剂量辐照下会造成纤维熔点和熔融热焓降低,法线方向晶粒平均尺寸有明显变小;辐照交联大大提高了纤维的热尺寸稳定性。

Crosslinking of ultra-high molecular weight polyethylene fibers(UHMWPE fibers)is investigated by means of electron beam irradiation.The dose of irradiation is from 20 kGy to 1000 kGy.The structure and mechanical properties of the fibers with different irradiation dose are discussed.The results show that the gel content of the fibers increases with the increasing irradiation dose.There are two effects of electron beam irradiation on fibers,crosslinking and chain scission.Melting point and melting enthalpy of fibers decrease with the increasing irradiation dose.The average size of crystal of normal direction is also decrease with the increasing irradiation dose.The thermal dimensional stability of fibers increases with the increasing irradiation dose.