区域性和立体选择性环开放性转化聚合,3替代环烯的聚合
Shingo Kobayashi1, Louis M Pitet, Marc A Hillmyer
1Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States.
Journal of the American Chemical Society
|March 31, 2011
概括
研究人员使用3位置换的cis-cyclooctenes的环开放转化聚合 (ROMP) 合成了新的线性低密度聚乙烯 (LLDPE) 模型. 这种方法精确地控制了聚合物结构,产生了高质量的聚乙烯材料.
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:
- 线性低密度聚乙烯 (LLDPE) 是一种具有广泛工业应用的多功能聚合物.
- 对聚合物微结构的精确控制对于定制LLDPE特性至关重要.
- 现有的合成路线可能对区域规律性和立体规律性提供有限的控制.
研究的目的:
- 为了合成具有受控微结构的模型线性低密度聚乙烯 (LLDPE) 样品.
- 为了研究3位置换的cis-cyclooctenes (3RCOEs) 的环开放元解聚合 (ROMP).
- 评估替代剂大小对聚合选择性的影响.
主要方法:
- 合成具有不同R组 (甲基,乙基,基,基) 的3替代 cis-cyclooctenes (3RCOEs).
- 使用格拉布斯催化剂对3RCOE进行环开元化聚合 (ROMP).
- 由此产生的聚合物3RCOE的化产生模型LLDPE.
主要成果:
- 3RCOE的ROMP进行了高的区域和立体选择性,产生了具有高头到尾区域规律性和跨立体规律性的多聚烯胺.
- 聚合选择性随着R替代剂的大小而增加.
- 化产生了精密的LLDPE,其R替代物精确地位于每八个骨干碳中的一个.
结论:
- 3RCOE的ROMP提供了一个精确的方法来合成模型LLDPE.
- R替代物的大小影响了聚合物的区域和立体选择性.
- 这种方法可以为先进的材料应用创建明确的LLDPE结构.
相关概念视频
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