论文部分内容阅读
本文测定了在0-50℃温度范围内,由~(60)Coγ射线引发聚合的聚甲基丙烯酸三乙基锡酯的立构规整度。用~(13)C-NMR测定聚合物分子链的立构规整度,如预料的那样,以间同立构为主,并随着聚合温度的升高间同立构等规度降低。由实验结果计算出的控制立构规整度的活化能参数是:全同和间同增长的活化焓与活化熵的差值分别为10.2kJ·mol~(-1)和19.8J·k~(-1)mol~(-1)。本文还测定了~(119)Sn与~(13)C原子之间的自旋偶合常数。
In this paper, the stereoregularity of polymerized triethylpolysylate initiated by ~ (60) Coγ-ray at 0-50 ℃ was measured. The stereoregularity of the molecular chain of the polymer was measured by ~ (13) C-NMR. As expected, the syndiotacticity was dominant, and the syndiotactic isotacticity decreased as the polymerization temperature increased. The activation energy parameters for the control of tacticity calculated from the experimental results are as follows: the difference between the activation enthalpy and the activation entropy for the same and the same growth are respectively 10.2 kJ · mol -1 and 19.8 J · k ~ 1) mol ~ (-1). The spin coupling constants between ~ (119) Sn and ~ (13) C atoms were also determined.