在 styrene 和 L-Lactide 的聚合中使用 Cyclopentadienyl-Silsesquioxane 复合物
Joan Vinueza-Vaca1, Shoaib Anwar2, Salvatore Impemba2
1Department of Organic and Inorganic Chemistry, Alcalà University, Campus Universitario, 28871 Alcala de Henares, Spain.
Polymers
|October 16, 2025
概括
两种新的复合物有效催化聚合反应. 一个生产合成聚乙烯,而另一个控制L-乳酸的环开放聚合,证明了多功能催化应用.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物科学 聚合物科学
- 催化剂是一种催化剂.
背景情况:
- 复合物中的silsesquioxane-cyclopentadienyl复合物为催化提供了独特的结构性质.
- 开发有效的催化剂,用于对商品和可生物降解聚合物的受控聚合,至关重要.
研究的目的:
- 为了合成和评估两个新型的silsesquioxane-cyclopentadienyl复合物用于聚合.
- 为了研究它们在烯的齐格勒-纳塔聚合和L-乳化物的环开聚合 (ROP) 中的有效性.
主要方法:
- 合成两种复合物:[Ti(η5-C5H4SiMeO2Ph7Si7O10-κO) Cl2] (1) 和[Ti(η5-C5H4SiMe2OPh7Si7O11-κ2O2) Cl] (2). 这两种复合物的合成方法是:
- 对复合物1与甲基氨酸 (MAO) 进行烯聚合的评估.
- 在溶液和融化条件下,对L-乳酸ROP的复合2与醇的评估.
- 使用13C NMR和分子量分析 (Mn, Đ) 的表征.
- 运动分析和计算研究.
主要成果:
- 复杂的1催化合成乙烯聚合,具有高的立体规律性和狭窄的分散性 (Mn = 5.2-8.2 kDa).
- 复合物2在溶液条件 (100°C) 下达到高达95%的L-乳ROP转化和高转化 (3000等值). 在1小时内) 在化条件下 (175°C) 具有良好的分子量控制 (Đ = 1.19-1.32).
- 动力学研究表明,对于ROP,一级依赖于单体度.
结论:
- 合成的复合物是有效的催化剂,用于生产合成聚乙烯和L-乳的受控ROP.
- 这些催化剂在各种条件下显示出对商品和可生物降解聚合物合成的多功能性.
- 计算洞察力为未来的催化剂优化和开发提供了基础.
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