紧张热定型工艺对多壁碳纳米管/聚醚醚酮复合纤维结构和性能的影响

采用熔融共混纺丝工艺制备多壁碳纳米管(MWCNTs)质量分数分别为0.1%和0.5%的MWCNTs/PEEK(聚醚醚酮)复合纤维,研究了紧张热定型过程中热定型温度和降温速率对复合纤维结构和性能的影响。采用TEM、SEM、DSC、DMA、XRD和单纤维电子强力仪研究了复合纤维的形貌、结构和性能。结果表明:复合纤维的热定型温度和冷却降温速率对其杨氏模量、拉伸强度和断裂伸长率均有影响,经过热定型处理,复合纤维内部MWCNTs的取向程度明显提高。280℃热定型、1.5℃/min冷却纤维的拉伸强度达384MPa,杨氏模量为0.62GPa,断裂伸长率28%,拉伸强度和杨氏模量分别较130℃热定型纤维提高了147%和19%,获得了优化复合纤维性能的最佳工艺条件。 

Effects of tension heat-set process on structures and properties of MWCNTs/PEEK composite fibers

Multi-walled carbon nanotubes(MWCNTs)/poly(ether ether ketone)(PEEK) composite fibers containing 0.1% and 0.5% mass fraction of MWCNTs were melt-spun,respectively.The effects of heat-set temperature and cooling rates on the structures and properties of the composite fibers were studied in the process of tension heat-setting process.TEM,SEM,DSC,DMA,XRD and tensile tester were used to characterize the morphology,structures and properties of the fibers.The results show that,the heat-set temperature and cooling rates affect the Young′s modulus,tensile strength and strain of the fibers.The heat-setting improves the orientation of MWCNTs in composite fibers.The tensile strength,Young′s modulus and strain of the fiber heat-set at 280 ℃ and cooling rate of 1.5 ℃/min are 384 MPa,0.62 GPa and 28%,respectively.The tensile strength and Young′s modulus are about 147% and 19% higher than that of the fiber heat-set at 130 ℃ and cooling rate of 1.5 ℃/min.Therefore,the optimized heat-set condition is obtained for the MWCNTs/PEEK composite fibers.