【摘要】 本文描述了用原位傅里叶变换红外 （FTIR）光谱法研究大丝束（8.89ktex）聚丙烯腈（PAN）纤维在空气和氮气气氛中低温（380℃以下）热解时,固态产物的动态变化过程。发现原有的许多谱带在吸收强度和位置方面均随其结构状态而变化,并出现了一些新的吸收谱带。同时,还获得了一般红外光谱中难以得到的一些微弱而有价值的规律光谱信息。并根据I₈₀₀cm^-1/I_2935cm^-1（吸收强度之比）参数的变化动态,观察到该试样在空气热解条件下发生更剧烈的芳构化反应。这就证实了氧对芳环分子脱氢缩合反应的地进作用。更多还原

【Abstract】 In this article the variations of characteristic peaks with heating temperaturefor large bundle PAN fibres were described under given temperature（below 380℃）and atmospheric environment （air or nitrogen） by in-situ Fourier Transform In-frared Spectroscopic method （FTIR）. From the spectrogram it is observed that theintensities and frequency of some original absorption bands varies as the structurechanges and some new absorption bands appeared simultaneously. Meanwhile, someweak and vauble regular spectrum was also observed, which is difficult to obtainin ordinary IR spectrum. Taking absoption intensities of aromatic C-H groups(I_800cm^-1) and aliphatic C-H groups (I_2935cm^-1) for example, the IR aromaticitywhich equals to the ratio of aromatic hydrogen amount to aliphatic hydrogenamount was calculated approximately. The results showed that the aromatizationof the structure of the sample took place rapidly in air pyrolysis. This provesoxygen promoting dehydrogenation and condensation reaction of macromolecules.更多还原