PE-UHMW对聚甲醛力学性能及非等温结晶的影响研究

Effect of PE-UHMW on Mechanical Properties and Nonisothermal Crystallization of Polyoxymethylene

制备了一系列聚甲醛/超高相对分子质量聚乙烯(POM/PE-UHMW)共混物,并通过力学性能测试,差示扫描量热仪及扫描电子显微镜等分析了共混物的结构和性能,分别采用Avrami以及莫志深理论对POM及POM/PEUHMW(100/1)非等温结晶动力学进行了理论分析,利用Kissinger方法对其结晶活化能进行了计算。结果表明,当PE-UHMW含量为1%(质量分数,下同)时,共混物的缺口冲击强度达到最大值,较纯POM提高了约24.3%;同时其降低了POM的结晶速率和结晶活化能,但相对结晶度稍有提高。

Blends of polyoxymethylene(POM)/ultra-high molecular weight polyethylene(PEUHMW)were prepared.The structure and performance of the blends were analyzed by mechanical property testing,DSC and SEM.When the content of PE-UHMW was 1 wt %,the notched impact strength of the blends was 1.24 folds that of neat POM.Two methods,namely,Avrami and Mo,were used to analyze the nonisothermal crystallization kinetics of POM and POM/PEUHMW(100/1)blends.The activation energy was evaluated by the Kissinger method.The crystallization rate and crystallization activation energy of POM decreased with adding 1wt% PEUHMW,while the crystallinity increased.