采用溶液共聚合法合成丙烯腈(AN)与衣康酸(IA)的共聚物.借助傅里叶变换红外光谱和差示扫描量热分析研究了共聚单体IA含量对聚丙烯腈(PAN)结构及环化反应动力学的影响.结果表明,IA的加入促进环化反应在低温下引发,并有效缓解集中放热.随着IA含量的增加,放热反应速率降低,放热峰变宽.采用Kissinger方法计算了不同IA含量的环化反应动力学参数,结果表明,IA可以显著降低环化反应的活化能.但是随IA含量的增加,自由基机理引发的反应活化能增加.
Polyacrylonitrile homopolymer (PAN) and copolymers with itaconic acid (IA) were prepared by solution copolymerization. The effect of IA content on the structure and kinetics of cyclization reaction of polyacrylonitrile polymers were studied by FTIR and DSC. It was found that the introduction of IA promoted the cyclization initiated at low temperature and eased the heat concentration. With the increasing amount of IA, the rate of exothermie reaction decreased with a broadened exothermic peak. Kinetic parameters of cyclization of PAN and P(AN-co-IA) were obtained from the Kissinger method, It showed that the activation energy of cyelization reaction was significantly reduced by the incorporation of IA. However, the Ea of cyclization that initiated through radical mechanism increased with IA content.