金属催化同步链和阶段生长基聚合:乙烯基聚合物和聚的结合
Masato Mizutani1, Kotaro Satoh, Masami Kamigaito
1Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Journal of the American Chemical Society
|May 12, 2010
概括
这项研究引入了同时连锁和阶段增长聚合,创造了新的线性随机共聚合物. 这些独特的聚合物含有乙烯和聚单元,具有可调性结构和可降解性.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 有机合成 有机合成
背景情况:
- 传统的聚合方法分为两个不兼容的家族:链式增长和阶段式增长.
- 在单一工艺中实现连锁和渐进增长聚合的同时实现一直是一个重大挑战.
研究的目的:
- 开发一种用于同时连锁和渐进增长聚合的新方法.
- 合成线性随机共聚合物,并结合了乙烯基聚合物和聚单位.
- 探索催化剂和单体料比对共聚合物结构和特性的影响.
主要方法:
- 甲基烯酸盐 (MA) 和3-丁-2-烯酸 (1) 的金属催化基共聚.
- 使用特殊的催化剂,如CuCl/hexamethyltriethylenetetramine和RuCp*Cl ((PPh ((3)) ((2)),用于线性共聚合物形成.
- 采用NMR和MALDI-TOF-MS进行详细的机制研究和聚合物表征.
主要成果:
- 成功合成了几乎理想的线性随机共聚合物,其中包括单一链中的乙烯基和聚单位.
- 证明了特定的催化剂 (CuCl/配体,基于Ru) 产生线性结构,而其他 (CuCl/不同配体,FeCl(2) 产生分支聚合物.
- 展示了通过调整单体料比率来调整共聚合物架构从随机到多块结构的能力.
- 通过甲醇化证实了合成的共聚合物的可降解性.
结论:
- 通过精心选择的金属催化基共聚化,可以实现同时连锁和阶段增长的聚合.
- 催化剂和反应条件的选择批判性地决定了得到的聚合物结构 (线性与分支).
- 合成的共聚合物具有可调节的结构和容易降解,为先进的材料应用开辟了道路.
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