中文摘要：

采用傅里叶变换红外光谱（FTIR）和广角X射线衍射（WAXD）研究了处理温度、处理时间、气体氛围对聚丙烯腈（PAN）均聚物及其共聚物P[丙烯腈（AN）/甲基丙烯酸甲酯（MMA）/衣康酸（IA）]热处理过程中结构演变的影响.FTIR结果表明,在氮气中,环化反应可以大量出现,但脱氢反应较少;而在空气氛围中,环化反应和脱氢反应都可以大量发生.氧气对PAN均聚物的环化反应有抑制作用,而对P（AN/MMA/IA）的环化反应有促进作用.WAXD结果表明,PAN均聚物的预氧化反应首先发生在非晶区,而后发生在晶区.在240℃时,t=1h,环化反应主要发生在非晶区;t≥1.5h,主要发生在晶区.

英文摘要：

The influences of treatment temperature, treatment time and atmosphere on the structural evolution of polyacrylonitrile （PAN） homopolymer and related copolymer of poly （aerylonitrile-co-methyl methacrylate-co-itaconic acid） [P （AN/MMA/IA）] during heat treatment were studied by using Fourier transform infrared spectroscopy （FTIR） and wide-angle X-ray diffraction （WAXD）. The results of FTIR indicate that the cyclization reaction occurs in a large amount under nitrogen, but there was less of dehydrogenation. Under air, both of cyclization and dehydrogenation happen in a large amount. Oxygen has a negative effect on the cyclization of PAN homopolymer, but has a positive effect on the cyclization of P（ AN/ MMA/IA）. The results of WAXD indicate that the cyclization occurs in the amorphous region in the PAN homopolymer at first and extends to the crystalline region as the proceeding of cyclization. Cyclization occurs mainly in the amorphous region at 240 ℃ when t = 1 h and in the crystalline region when t ≥ 1.5 h.