碳纤维对聚丙烯结晶行为的影响

本文用偏光显微镜和示差扫描量热计(DSC)方法研究了碛纤维对聚丙烯结晶行为的影响。碳纤维表面对聚丙烯结晶过程具有明显的促进作用,纤维表面成核密度轻高,结晶生长成为横穿结晶,结晶特征温度随碳纤维加入而有不同程度的升高。结晶动力学表明:结晶生长本质仍是球晶机理,促进聚丙烯结晶的原因是碳纤维使结晶过程的表面自由能降低。

EFFECT OF CARBON FIBER ON THE CRYSTALLIZATION OF POLYPROPYLENE

Polarizing microscopy and differential scanning calorimetry (DSC) were used to study the effect of carbon fiber on the crystallization of polypropylene (PP). It is shown that the surface of carbon fiber displays a high propens ity to nucleate PP crystallization. The nuclei density at the surface of carbon fiber is much higher than that in the bulk area, and the resulting radial growth produces a type of transcrystalline structure, and the characteristic temperature of crystallization increases with carbon fiber concentration. By the study of the crystallization kinetics it is concluded that the crystallization in spherulitic in nature, carbon fiber promotes the crystallization of PP by decreasing it's crystalline surface free energy.