【摘要】 采用原子转移自由基聚合的方法将聚乙二醇(PEG)接枝到多壁碳纳米管(MWNTs)上,然后利用平板硫化机制备出聚甲醛(POM)/MWNTs-PEG复合材料。利用扫描电子显微镜、透射电子显微镜、红外光谱和热重分析对MWNTs-PEG进行表征。通过差式扫描量热仪研究了该复合材料结晶行为的变化,用Jeziorny法和Mo法对其进行非等温结晶动力学分析。结果表明,PEG均匀接枝到MWNTs上;MWNTs-PEG的加入具有异相成核的作用,使POM结晶温度向高温区移动,结晶速率提高,半结晶时间缩短;结晶速率常数值增加,F(T)值降低;有效结晶活化能降低;MWNTs-PEG最终起到促进POM结晶的作用。更多还原

【Abstract】 Poly(ethylene glycol)(PEG) was grafted onto multiwalled carbon nanotubes(MWNTs) by atom transfer radical polymerization, and its structure and performance of MWNTs-PEG was investigated with scanning electron microscopy,transmission electron microscopy,infrared spectroscopic and thermogravimetric analysis. The POM/MWNTs-PEG composite films were prepared by heat compression, and their crystallizations behaviors and non-isothermal crystallization kinetics were studied by differential scanning calorimetry using Jeziorny ’s and Mo ’s methods. The effect of MWNTs-PEG on the performance of composites was also investigated. The results indicated that PEG was successfully grafted onto MWNTs, and the presence of MWNTs-PEG generated a heterogeneous nucleation effect on the crystallization of POM. As a result, the crystallization temperature and crystallization rate were improved, and the crystallization time was shortened accordingly. The crystallization kinetic investigation indicated that the crystallization rate constant of POM/MWNTs-PEG composites increased but the F(T) value decreased. Moreover,the effective crystallization activation energy was reduced, suggesting a promoting effect of MWNTs-PEG on the crystallinity of POM.更多还原