韩娜,吴潮,寇晓慧,李平宽,张兴祥

• 1:天津工业大学省部共建分离膜与膜过程国家重点实验室
• 2:天津工业大学先进纤维与储能技术重点实验室
• 3:天津工业大学材料科学与工程学院

摘要(Abstract)：

为探究预氧化阶段紫外（UV）辐照聚丙烯腈（PAN）纤维诱导环化交联反应的机理，对紫外辐照后的PAN纤维（UVRPAN）在不同气氛下进行热处理，分析温度对纤维内交联结构、环化结构和热性能的影响。结果表明：随着热处理温度增加，UVRPAN纤维中的交联结构与环化结构增加，环化结构长度增加，交联度由34.4%逐渐上升至44.9%，氰基转化率由33.5%升高至58.4%;O2促进了纤维内环化结构的产生，并延长了环化结构长度；热处理后，UVRPAN内自由基的种类未发生改变，自由基浓度随热处理温度升高而降低；随热处理温度升高，空气条件下环化放热焓值由550.9 J/g降低至431.9 J/g，氮气条件下由423.1 J/g降低至372.6 J/g，证实热处理可缓解预氧化过程中的集中放热。

关键词(KeyWords)： 热处理;紫外辐照;聚丙烯腈;碳纤维;环化结构;交联结构

Abstract:

Keywords:

基金项目(Foundation): 天津市科技军民融合重大专项资助项目（18ZXJMTG00110）

作者(Author): 韩娜,吴潮,寇晓慧,李平宽,张兴祥

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