DSC法研究聚丙烯腈纤维的环化反应动力学

DSC study on cyclization reaction kinetics of polyacrylonitrile fiber

通过差示扫描量热(DSC)法研究了聚丙烯腈(PAN)纤维的热性能及其在不同升温速率下的环化反应动力学。结果表明:PAN纤维在氮气气氛中只发生环化反应,DSC曲线的放热峰尖而窄。根据Kissinger法得出其活化能为66.86 kJ/mol,反应级数为1。由DSC曲线及外推法得到升温速率为0时,其放热峰峰值为256.8℃。随着稳定化时间的增加,PAN纤维的环化度增大,纤维稳定化程度提高。

The thermal properties and the cyclization reaction kinetics of polyacrylonitrile（ PAN ） fiber were studied at different heating rates by differential scanning calorimetry （DSC）. The results showed that no reaction occurred in nitrogen atmosphere but the cyclization reaction. The exothermal peaks of DSC curves were sharp and narrow. The activation energy was calculated as 66. 86 kJ/mol and the reaction was decided as the first-order reaction according to Kissinger method. The exothermal peak value was 256.8 ~C at the heating rate of 0 according to DSC curves and extrapolation method. The cyclization degree of PAN fiber was increased and the stabilization degree was improved as the stabilization time was increased.