多壁碳纳米管/聚丙烯复合材料的结晶行为

采用表面接枝十六烷烃的方法对多壁碳纳米管(MWCNTs)进行改性, 通过溶液共混法制备多壁碳纳米管/聚丙烯(MWCNTs/PP)复合材料, 并研究了MWCNTs/PP的结晶行为。结果表明, 3%(质量分数)表面接枝十六烷烃的MWCNTs在PP基体中分散良好, 达到纳米级的分散。加入接枝MWCNTs后, PP的结晶结构未发生改变, 依然是α晶型。接枝MWCNTs对PP有异相成核的作用, 加入接枝MWCNTs使PP的成核及晶体生长方式发生变化。加入3%(质量分数)接枝MWCNTs 以后, PP的结晶温度升高了8℃, 结晶速率提高了1倍, 结晶度提高了3%, 球晶尺寸减小。

Crystallization behaviors of MWCNTs/PP composites

Multi-walled carbon nanotubes(MWCNTs) were modified through grafting C16 alkyl chains.MWCNTs/polypropylene(PP) composites were prepared through solution blending.The crystallization behaviors of MWCNTs/PP composites were studied.The experimental results show that 3%(mass fraction) grafted MWCNTs with C16 alkyl chains could be dispersed very well in PP matrix.The grafted MWCNTs could be dispersed on nano-scale.The presence of the grafted MWCNTs does not change the α-crystal form of PP.The introduction of the grafted MWCNTS induces the heterogeneous nucleation of PP in the grafted MWCNTs/PP composites,which will affect the mechanism of nucleation and the crystal growth of PP.After the addition of 3%(mass fraction) grafted MWCNTs in the PP matrix,the crystallizing temperature is increased by 8 ℃,the crystallizing rate is improved one time,and the crystallinity of PP matrix is increased by 3%.Moreover,the spherulity size decreases.