1,5-二烯的插入/异构聚合:功能性烯共聚合物和块共聚合物的合成
Phillip D Hustad1, Geoffrey W Coates
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA.
Journal of the American Chemical Society
|September 26, 2002
概括
催化剂使1,5-二烯的聚合成为可能,产生具有独特乙烯四甲单元的聚合物. 这一发现有助于制造具有维尼尔功能的聚烯共聚合物和块共聚合物.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属催化工艺
背景情况:
- 双 () 复合物是烯聚合物的有效催化剂.
- 1,5-二烯的聚合通常会产生具有特定微观结构的聚合物.
研究的目的:
- 为了研究使用bis(phenoxyimine) 催化剂对1,5-hexadiene的聚合.
- 阐明形成意想不到的聚合物微结构背后的机制.
- 探索这种催化系统在合成功能化共聚合物的应用.
主要方法:
- 用 bis ((phenoxyimine) 催化剂对1,5-hexadiene 的催化聚合.
- 使用光谱技术对得到的聚合物进行微结构分析.
- 对共聚合和块共聚合反应的研究.
主要成果:
- 聚合生成的聚合物含有预期的甲-1,3-cyclopentane单位和意想不到的3-乙烯四甲单位.
- 提出了一种反应机制来解释观察到的微观结构的形成.
- 催化系统成功应用于合成具有维尼尔功能的聚烯共聚合物和具有低多分散性的阻断共聚合物.
结论:
- 双 (氧胺) 催化剂系统驱动了一种不寻常的聚合途径,用于1,5-二烯.
- 这种催化系统为生产具有控制架构的功能化聚烯和块共聚合物提供了一条新的途径.
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