灵活的轴屏蔽策略,以改善使用8-环基纳甲α-二胺催化剂的乙烯 (Co) 聚合
Zhou Lu1, You Ge2, Shengyu Dai1,2
1Anhui Laboratory of Molecule-Based Materials, Key Laboratory of Functional Molecular Solids, Ministry of Education, School of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China.
灵活的8-cycloalkylnaphthyl连接物增强了后期过渡金属催化乙烯聚合,产生高分子量聚乙烯. 环基组比环基提高了催化剂性能,超过了刚性催化剂的性能.
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:
- 用8-或甲替代物的轴屏蔽对于高分子量聚乙烯合成至关重要.
- 晚期过渡金属催化剂对于乙烯聚合至关重要.
研究的目的:
- 为了研究使用8-cycloalkylnaphthyl α-diimine配体的柔性轴屏蔽对乙烯聚合物的影响.
- 为了比较不同环基组的和复合物的性能.
主要方法:
- 合成两种基于8-环基纳乙纳的α-二胺联体.
- 四种和复合物的制备和表征.
- 在乙烯聚合和共聚合过程中对催化活性和聚合物特性进行评估.
主要成果:
- 复合物表现出高活性,产生轻度分支,高分子量聚乙烯.
- 复合物表现出中度活性,产生高度分支的聚乙烯和E-MA共聚合物.
- 环基组在抑制链转移方面表现优于环基组.
- 灵活的8-cyclohexylnaphthyl催化剂在活性和分子量方面优于刚性8-arylnaphthyl催化剂.
结论:
- 灵活的轴屏蔽与8-cycloalkylnaphthyl连接物是有效的生产高分子量聚乙烯.
- 环基组的大小显著影响催化剂性能和聚合物分支.
- 基于循环基的配体在特定的聚合结果中比循环基和刚性平面替代剂具有优势.
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