预氧化时间对聚丙烯腈基碳纤维预氧丝结构与性能的影响

Influence of preoxidation time on the structure and property of PAN based CF preoxygenated wire

预氧化是制备碳纤维非常重要的一个环节,制得预氧化丝的性能直接决定最终碳纤维的性能,因此研究预氧化过程对预氧化丝结构性能的影响规律具有重要意义。通过广角X射线衍射点光源取向测试和小角X射线散射实验,计算得到了聚丙烯腈(PAN)基碳纤维原丝与不同处理时间下预氧丝取向度、线结晶度、长周期L、晶区厚度Lc、无定形区厚度La等微观结构参数。采用元素分析仪和单纤维强力仪研究了该系列PAN基碳纤维原丝、预氧丝的元素组成和力学性能随预氧化时间的变化,明确了PAN基碳纤维预氧丝内部微观结构参数、元素含量与其力学性能的关系。

Carbon fiber(CF)have been widely applied in many areas,for instance aerospace,traffic and transportation,sports leisure and etc.Preoxidation is very important process for preparing CF with high performance,which is closely related with the performance of preoxidized fibers.Therefore,it is important and promising to reveal the relationship between preoxidation and preoxidized fibers performance.Wide angle X-ray diffraction and small angle X-ray scattering were used to detect and calculated the orientation,crystallinity,long-periodic(L),thickness of crystalline(Lc)and thickness of amorphous(La)of polyacrylonitrile precursor fiber(PAN fiber)and different preoxidized fibers.Elemental analysis and single fiber strength tester were performed to investigate the change of fiber tenacity with elements composition for PAN fibers and preoxidizer fibers.The relationship between fiber microstructure,element and strength was fully revealed.