Kinetics of the cyclization and isomerization reactions in polyacrylonitrile based carbon fiber precursors during thermal‐oxidative stabilization,Journal of Applied Polymer Science

当前位置： X-MOL 学术 › J. Appl. Polym. Sci. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Kinetics of the cyclization and isomerization reactions in polyacrylonitrile based carbon fiber precursors during thermal‐oxidative stabilization
Journal of Applied Polymer Science ( IF 2.7 ) Pub Date : 2019-12-14 , DOI: 10.1002/app.48819
Ying Liu ₁ , Yan Xue _{2,

3} , Hong Ji ₂ , Jie Liu ₃

Affiliation

The kinetics of reactions in polyacrylonitrile (PAN) based carbon fiber (CF) production should be of significance to the guidance of process control, fiber structure formation. PAN precursor fibers were isothermally stabilized at 210, 225, 240, 255, and 270 °C, respectively, for 10 to 100 min in an air oven to study the kinetics of the cyclization and isomerization reactions. The structural evolution of PAN precursor fibers during thermal‐oxidative stabilization was characterized by Fourier transform infrared (FTIR) spectroscopy and solid state ¹³C nuclear magnetic resonance (¹³C NMR). The results indicate that the FTIR absorbance of CN (the resultant of the cyclization) in PAN shows a trend of first increasing and then decreasing. And then the NMR peak assigned to the carbon atoms linking imino groups (NH) proves the isomerization of CN into NH in pyridone structure. Based upon the FTIR absorbance method, the entire process of the cyclization and isomerization reactions is considered as a consecutive first‐order reaction. A kinetic model for the consecutive reaction has been established via the evaluation of the reaction rate constants of two single reactions. According to the model, the simulated kinetic curves of the characteristic groups (CN, CN, and NH) conform to the FTIR absorbance trends of these groups based on experimental data. This study is expected to furnish in‐depth information on the crucial reaction kinetics during stabilization of PAN precursors, which is of advantage to the process optimization of the CF production. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48819.

中文翻译：

聚丙烯腈基碳纤维前体在热氧化稳定过程中环化和异构化反应的动力学

聚丙烯腈（PAN）基碳纤维（CF）生产中的反应动力学对指导过程控制，纤维结构形成具有重要意义。PAN前体纤维在空气烘箱中分别在210、225、240、255和270°C下等温稳定10至100分钟，以研究环化和异构化反应的动力学。PAN前体纤维在热氧化稳定过程中的结构演变通过傅立叶变换红外（FTIR）光谱和固态¹³ C核磁共振（¹³ C NMR）来表征。结果表明的红外吸收 CN PAN中的环化结果显示出先增加后减少的趋势。然后分配给连接的亚氨基（碳原子的NMR峰 NH ）证明的异构化 CN 成 NH 在吡啶酮结构。基于FTIR吸收法，环化和异构化反应的整个过程被视为连续的一级反应。通过评估两个单一反应的反应速率常数，建立了连续反应的动力学模型。根据该模型，该特性基团的模拟动力学曲线（ CN， CN ，和 NH ）符合FTIR吸光度这些基团基于实验数据的趋势。预期该研究将提供有关PAN前体稳定过程中关键反应动力学的深入信息，这对CF生产工艺的优化是有利的。分级为4 +©2019 Wiley Periodicals，Inc.J.Appl。Polym。科学 2020，137，48819。

更新日期：2020-03-16

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南