原子转移激素聚合物的平衡常数的确定
Wei Tang1, Nicolay V Tsarevsky, Krzysztof Matyjaszewski
1Center for Macromolecular Engineering, Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|February 2, 2006
概括
修改后的菲舍尔 (Fischer) 模型
科学领域:
- 聚合物化学 聚合物化学
- 物理化学 物理化学
- 有机化学 有机化学
背景情况:
- 原子转移基聚合 (ATRP) 取决于活跃物种和休眠物种之间的平衡.
- 精确确定ATRP平衡常数 (K(ATRP)) 对于控制聚合而言至关重要.
- 使用费舍尔方程的现有方法仅限于低转换率和K ((ATRP) 值.
研究的目的:
- 开发和验证修改后的菲舍尔方程,以在更高的转换率下确定K (ATRP).
- 准确测量各种催化剂和基化物中的K (ATRP).
- 为了研究ATRP中的结构-反应性关系.
主要方法:
- 修改过的费舍尔方程,包括催化剂和启动剂度的变化.
- 动力模拟以验证新的方程.
- 紫外线光谱测量用于监测铜种 (X-Cu(II)).
- 气相色谱 (GC) 用于追踪启动器度.
主要成果:
- 修改后的方程准确地确定了K(ATRP) 在转换率>10%和K(ATRP) >10(-7).
- 成功确定了几个催化剂/基化物系统的K (ATRP) 值.
- 证明了结构变异对ATRP组件反应性的影响.
结论:
- 修改后的菲舍尔方程扩展了在ATRP中确定平衡常量的适用性.
- 准确的K ((ATRP) 值对于精确控制聚合过程至关重要.
- 了解结构-反应关系有助于设计高效的ATRP系统.
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