摘要
用1H NMR、13C NMR谱、自旋-晶格弛豫时间(T1)和自旋-自旋弛豫时间(T2)研究了丙烯腈在60Coγ射线辐射聚合后的大分子结构变化与大分子链的运动.结果表明随着辐射剂量增大,在单体形成聚合物的过程中,聚合物主链上出现了少量的-OH基团,继续增大辐射剂量,-OH部分被氧化.对聚合物溶液的变温氢谱的研究表明,溶剂中的残余水与上述-OH形成氢键,且随着温度升高氢键被破坏,同时H2O与-OH之间还存在着质子交换.利用13C NMR谱对丙烯腈辐射聚合的产物进行了序列结构分析.对T1和T2的研究表明,辐射剂量的增大并未影响到聚丙烯腈的链运动,证明了在丙烯腈的辐射聚合过程交联反应未发生.
^60Co 7 irradiation induced polymerization of acrylinitrile (AN) was studied by ^1H and ^13C NMR spectroscopy. The results show that the signal intensities of AN monomer peaks decrease after irradiation, and this is accompanied by the appearance of a polymer peak, whose signal intensity increases with the irradiation dose. The sequence distribution of polyacrylonitrile was assigned using ^13C NMR data. The results of variable temperature experiments indicate that there exist hydrogen bonds, as well as proton exchange, between residual water and the -OH group on the polymer. Relaxation time measurements show that the motion of polymer segments is not influenced significantly by the increase of irradiation dose.
出处
《波谱学杂志》
CAS
CSCD
北大核心
2006年第2期187-192,共6页
Chinese Journal of Magnetic Resonance
基金
波谱与原子分子物理国家重点实验室资助课题(T012406)