关于激素聚合过程中终结的激活能量,在低转换条件下研究
Majed M Alghamdi1,2, Gregory T Russell2
1Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
Polymers
|November 27, 2024
概括
这项研究研究了极端聚合过程中终点的激活能量,揭示了它取决于链条长度. 这些发现为理解聚合动力学提供了新的框架.
科学领域:
- 聚合物化学 聚合物化学
- 化学动力学 化学动力学
- 物理化学 物理化学
背景情况:
- 极端聚合 (RP) 终结速率系数 (
) 由于链长度依赖而复杂. - 终结的激活能量 (E_a(
)) 尚未在机械上进行详细的研究. - 了解E_a (
) 对于控制聚合过程至关重要.
研究的目的:
- 首次机械地研究激素聚合过程中终点 (E_a(
)) 的激活能量. - 开发一个分析框架来预测E_a (k_t) 和E_a (DP_n).
- 在各种RP系统中探索E_a (k_t) 和E_a (DP_n).
主要方法:
- 在烯和甲基烯酸盐的稀释溶液低转换同聚合过程中对E_a (
) 的实验测量. - 重新分析烯和甲基甲酸甲基的散装聚合数据.
- 开发链长度依赖终止 (CLDT) 的分析框架.
主要成果:
- 稀释溶液聚合产生了 25-39 kJ mol-1 的 E_a(
) 值,这表明短链的强CLDT. - 大量聚合的数据给出了18-24kJmol-1的E_a(
) 值,这表明长链的CLDT很弱. - 结果与CLDT的复合模型保持一致,并通过新的分析框架进行合理化.
结论:
- E_a(
) 受到除了激光扩散激活能量之外的因素的影响. - 开发的框架成功地预测和解释了E_a (k_t) 和E_a (DP_n).
- 预测是为E_a ((
) 和E_a ((DP_n) 在具有烯酸盐,光启动或链转移的系统中进行的.
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