在催化剂转移共聚化中对共聚化动力学进行定量比较,以合成聚硫
Yifei He1, Christine K Luscombe2
1Department of Materials Science and Engineering, University of Washington Seattle USA.
概括
这项研究量化了库马达催化剂转移聚合物 (KCTP) 中的芬单体的动力数据,从而能够准确地预测共聚合物结构. 单体结构显著影响反应性和由此产生的多烯共聚物结构.
科学领域:
- 聚合物化学 聚合物化学
- 有机电子 有机电子
- 材料科学 材料科学 材料科学
背景情况:
- 聚二是广泛研究的合聚合物,对有机电子学至关重要.
- 库马达催化剂转移聚合 (KCTP) 允许合成多种多聚合物共聚合物 (随机,块,梯度).
- 缺乏烯单体的定量动态数据,阻碍了精确的共聚合物合成和结构预测.
研究的目的:
- 使用KCTP测量3 - 赫西尔提奥芬与四种提奥芬共纳体的反应率和聚合速率常数.
- 为了研究单体结构对共聚合过程中的反应性的影响.
- 根据获得的运动数据来预测和验证共聚物结构.
主要方法:
- 调整梅奥-易斯方程以确定反应率.
- 对聚合速率常数的第一阶动态行为的分析.
- 批量联合聚合实验与等分单体比率.
主要成果:
- 类似于3 - 基基的3 - 基基和3 - 基基基,表现出相当的反应性,产生随机的共聚物.
- 带有分支的侧链的3-(2-乙基) 烯显示反应性降低,导致渐变共聚合物.
- 3-(4-octylphenyl) thiophene,由于硬质障碍,未能在共聚合中维持链聚合.
结论:
- 单体结构极大地影响了KCTP中的反应性和共聚合结果.
- 准确的动力学数据对于可预测的聚乙烯共聚物结构的可预测合成至关重要.
- 这项工作为设计先进的合聚合物提供了宝贵的动态见解.
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