热处理对PAN纤维环构化结构及后续反应的影响  

Effect of the cyclized structure of PAN fiber on its subsequent reaction

作　　者：杨策宇[1] 李常清[1] 谢怀玉[1] 瓮龙明[1] 徐樑华[1] 

机构地区：[1]北京化工大学碳纤维及功能高分子教育部重点实验室,北京100029

出　　处：《材料热处理学报》2011年第3期10-13,18,共5页Transactions of Materials and Heat Treatment

基　　金：国家科技部"973"项目(2006CB605302;2006CB605303)

摘　　要：在氮气气氛下,对PAN纤维分别在210～260℃进行热处理,得到不同环构化结构的PAN纤维,并在空气气氛中进行热稳定化处理。借助红外吸收光谱(FT-IR)、固体核磁(13C-NMR)、差示扫描量热分析(DSC)、元素分析(EA)和热重分析(TG)等测试手段,研究氮气中形成的PAN纤维环构化结构特点,及对后续热环化氧化反应的影响。结果表明:在氮气气氛中,随热处理温度从210℃升至260℃,PAN纤维的环化程度提高,不同热处理温度导致了不同PAN纤维环构化结构的形成:其中210～240℃区间内脱氢反应逐渐剧烈,-C=C-C=N-结构逐步增多;230～260℃区间,其易于捕获氧的官能团-CH2-C=C-NH-逐渐增多;随前期热处理温度的升高,前期形成的环构化结构使得后期环化和初步氧化反应可在更低的温度下进行,反应更加缓和,环化更加彻底,有利于生成更加完善的耐热网状梯形结构。The cyclized structure of PAN fiber after treated at various ambient temperatures 210-260 ℃ under nitrogen atmosphere was investigated by means of FTIR,13 C-NMR,DSC,EA and TG analysis.The results indicate that different cyclized chemical structure is obtained for PAN fiber heat-treated at different temperatures and the extent of cyclization increases with increasing temperature at 210-260 ℃.Between 210-240 ℃,the dehydrogenation reaction occurs intensely and leads to the formation of the-C = C-C = N-structure.By heating further,the-CH2-C = C-NH-structure which can be oxidized easily increases gradually at 230-260 ℃.The subsequent cyclization and oxidation in air can occur under lower temperature and more completely due to the contribution of this initial cyclized structure.

关 键 词：PAN纤维 预氧化 环构化结构 

分 类 号：TQ342.31[化学工程—化纤工业]