摘要
用1HNMR谱和质子自旋弛豫时间研究了γ射线辐射引发的α-甲基丙烯酸的聚合反应、其聚合转化率和聚合物链运动与吸收剂量和剂量率的关系。对比了聚合物在不同溶剂中各质子化学位移的变化。结果表明α-甲基丙烯酸聚合转化率随着吸收剂量的增加而增大,吸收剂量率则反之。从自旋-晶格弛豫时间(T1)和自旋-自旋弛豫时间(T2)测定中得知,自旋-晶格弛豫时间几乎不随剂量变化而变化。当聚合转化率较大时,聚合物链运动呈多指数弛豫特征。在重水溶剂中加入少量的氘代NaOH,不仅提高了谱图的分辨率,也使各质子化学位移发生了移动。
The polymerization conversion and segment motion of α- methacrylic acid were studied using ^1H NMR spectra, spin-lattice relaxation time and spin-spin relaxation time. Meanwhile, the change of the proton chemical shifts in different solvents was observed. The results indicate that the polymerization conversion of α- methacrylic acid increases with the absorbed dose rising and decreases with the dose-rate rising. The proton spin-lattice relaxation time of α- methacrylic acid keeps unchanged while the spin-spin relaxation time shows a double exponential feature. It is found that the proton chemical shifts vary with the blending solvent.
出处
《核技术》
EI
CAS
CSCD
北大核心
2006年第10期742-745,共4页
Nuclear Techniques
基金
波谱与原子分子物理国家重点实验室(T012406)资助
