预氧化过程中PAN纤维皮芯结构的变化

摘要: 借助红外测试（FTIR）、元素分析（EA）、扫描量热分析（DSC）和扫描电子显微镜（SEM）系统研究了五种聚丙烯腈（PAN）纤维在预氧化过程中纤维皮芯结构的变化、差异、规律及其与热化学反应、结构变化的关联。结果表明：预氧化过程中PAN纤维皮芯比的变化与纤维组成、结构和致密性等化学与物理性质密切相关。在一定预氧化条件下,皮芯比的变化与纤维热化学反应特性的差异、直径收缩率和密度的变化存在良好的对应关系。最终预氧化纤维的皮芯比与炭纤维的力学性能密切相关。

Abstract: The core/shell structure of polyacrylonitrile (PAN) fibers formed during preoxidation was investigated by DSC, FTIR, SEM, optical microscopy and density measurement. Five precursors were used to correlate the core/shell structure with their thermochemical reactivity. It was found that the morphologies of the core/shell structures are highly relevant to the reactivity, microstructure and density of PAN fibers, and the quality of the resultant carbon fibers depends strongly on the degree of preoxidation.