【摘要】 本文利用加入各种类型的成核剂的方法得到了不同结晶形态的聚乙烯(PE)和聚丙烯(PP);用偏光显微镜研究了各种成核剂的成核作用和结晶形态;用显微激光分析仪和差动热分析(DSC)研究了各成核剂对结晶和熔融过程的依赖关系,并测定了它们对结晶度的依赖关系,研究了它们对拉伸力学性能的影响。研究结果表明,成核剂可以明显地使晶粒细而均匀,能改变结晶和熔融速率,以适应各种工艺性要求,但对力学性能的影响较小,因此可以根据工艺和使用要求选用不同的成核剂。更多还原

【Abstract】 The different crystal forms of polyethylene(PE)and polypropylene(PP) from the melt making use of various nuclearting agents were studied by optical microscope crossed polarizers.The dependence of the crystallisation and melt process on the nuclearting agents was studied using a Laser-Optical Microscopic Analyzer and a Differential Scanning Calorimeter(DSC).And their crystallinity and tensile mechanical properties were measured.The results show:the nuclearing agents can obviously change the size of crystalline grains(see Figs.3 and 4),the rate of melting and crystallisation(see Figs. 5 and 6).But their mechanical properties changed slightly.Therefore,the nucleating agents can improve technological behavior of PE and PP in injection process,to decrease the defections of production,such as hollow, voids and so on.更多还原