聚醚醚酮及其碳纤维复合材料——恒温结晶动力学的研究

本文研究了聚醚醚酮(PEEK)和以PEEK树脂为基体的碳纤维复合材料(APC-2)在恒温条件下的结晶行为。采用差示扫描量热仪(DSC)测定从熔体和橡胶体结晶过程中热焓的变化。利用Avrami方程分析了PEEK和APC-2试样的恒温结晶动力学。PEEK从熔体和橡胶体结晶的活化能分别为532.1和531.7KJ/mol,Avrami指数的平均值分别为5.0和3.9;而APC-2则分别为444.2和432.5KJ/mol,3.5和2.3。这些实验结果表明,APC-2试样中碳纤维表面对PEEK树脂基体具有显著的成核作用,能降低其结晶活化能,因而导致PEEK树脂基体结晶速率加快和促进其结晶更加完整。

THE STUDY ON KINETICS DURING ISOTHERMAL CRYSTALLIZATION OF POLY(ETHER-ETHER-KETONE) (PEEK) AND ITS CARBON FIBER COMPOSITE

A study has been made of the crystallization behavior of poly(ether-ether-ketone), PEEK, and the matrix of its carbon fiber composite, APC-2, under isothermal crystallization conditions. A differential scanning calorimeter, DSC, was used to monitor the energetics of the crystallization process from the melt and from the rubbery amorphous state. The Avrami equation was used to analyze the kinetics of isothermal crystallization of PEEK and APC-2. The mean Avrami exponents, n, for PEEK are 5,0 and 3.9 for the crystallization process from the melt and from the rubbery amorphous state, respectively, while APC-2 are 3.5 and 2.3 on the same conditions. The activation energies for PEEK are 532.1 KJ/mol for crystallization from the melt and 531.7 KJ/mol for crystallization from the rubbery amorphous state, while APC-2 are 444.2 and 432.5 KJ/mol on the same conditions. The results of our studies show that the surface of carbon fiber of APC-2 samples has strong effect of nucleating agent on the crystallization of PEEK matrix, and decreases the activation energies of crystallization process of PEEK matrix, so that the crystallization rate and the degree of crystallization of PEEK matrix are increased.