炭纤维表面官能团异氰酸酯化及阴离子接枝尼龙6研究——(Ⅱ)接枝对CF/PA6复合材料中尼龙6等温结晶动力学的影响

THE ISOCYANATION OF CHEMICAL FUNCTIONS ON CARBON FIBER SURFACE AND ITS ANIONIC POLYMERIZATION OF POLYAMIDE 6 ——(Ⅱ) THE EFFECT OF GRAFTING OF CARBON FIBER ON THE KINETICS OF ISOTHERMAL CRYSTALLIZATION OF CF/PA6 COMPOSITES

利用差示扫描量热仪(DSC)研究了炭纤维(CF)表面官能团异氰酸酯化及其阴离子接枝尼龙6(PA6)对CF/PA6复合材料中PA6的等温结晶动力学的影响。结果表明,PA6的等温结晶过程主要为成核作用控制;未接枝的CF对PA6结晶起异相成核作用,提高了PA6的结晶速率;表面阴离子接枝PA6的CF对PA6结晶仍起异相成核作用,但由于增加了复合材料的界面粘结作用,同时又会阻碍PA6分子链的迁移运动,导致表面阴离子接枝PA6的CF/PA6复合材料中PA6组分的结晶速率虽比纯PA6大,但比未接枝PA6的CF/PA6复合材料小,且结晶度也有所下降。

Differential scanning calorimetry was used to investigate the effect of polyamide6(PA6) grafted carbon fiber(CF) by isocyanation on the isothermal crystallization kinetics of CF/PA6 composites. The results show that the isothermal crystallization of PA6 is dominated by nucleation while the ungrafed CF plays an role of heterogeneous nucleation agent in the process of crystallization of PA6 and increases its crystallization rate. The PA6 grafted CF still plays the role of heterogeneous nucleation agent in the CF/PA6 composites, however, its effect is less than that of the ungrafted CF. This may be ascribed to the improved interfacial adhesion between PA6 and CF in the composites where the movement of PA6 segments are inhibited, thus leading to reduction of the crystallization rate and the degree of crystallinity of PA6 in the composites.