用同等特异的可诺催化剂与烯共聚合时加入化1,4-丁
Takeshi Ishihara1, Takeshi Shiono
1Japan Chemical Innovation Institute, AIST Tsukuba, Central 5-8, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
Journal of the American Chemical Society
|April 21, 2005
概括
在使用特定的conocene催化剂对烯和丁共聚合过程中的化选择性地产生了1,2-插入的丁单位,显著提高了催化剂活性并防止了分支.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
背景情况:
- 烯酸催化剂对于烯酸聚合是至关重要的.
- 控制共聚合物中单体插入是材料性质的关键.
- 在修改聚合途径中的作用需要进一步阐明.
研究的目的:
- 为了研究气对烯和1,3-丁二烯的共聚变的影响.
- 为了选择性地合成聚 (?? 烯-兰-1,3-丁) 与受控的丁插入.
- 了解化条件下的布他迪因插入和链末的机制.
主要方法:
- 使用rac-dimethylsilylbis(2-methyl-4-phenylindenyl) 二 (Ph-Ind) 活性化改性甲基氨酸 (MMAO) 的烯和1,3-丁的联合聚合.
- 在聚合过程中添加.
- 13C核磁共振光谱仪用于对产生的共聚物质进行详细的结构分析.
主要成果:
- 添加气增加了约1000倍的催化剂活性.
- 化选择性地产生了只有1,2-插入布他单元的共聚物.
- 布达也被插入为四甲单元,其含量与没有的1,4插入单元相似;没有观察到循环或分支结构.
结论:
- 化将由1,4-二烯插入而形成的pi-基可诺物种转化为四甲链末.
- 这种转化允许持续的烯插入,从而产生受控的共聚合物结构.
- 该研究展示了一种具有功能化的多聚烯的选择性合成方法,具有增强的催化剂性能.
相关概念视频
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