具有增强活性和热稳定性的异质化哈夫尼复合物,对烯 (共聚合) 聚合具有较强的活性和热稳定性
Yongxin Liu1, Faqiang Niu1, Shaofeng Liu1,2
1Shandong Key Laboratory of High Performance Polyolefin Materials and Recycling, College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao, Shandong 266042, China.
新的异质合 hafnium 复合物在烯酸聚合过程中表现出增强的活性和热稳定性. 这些催化剂具有可调节的共聚合特性,促进了多烯催化剂的开发.
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:
- 哈夫复合物在烯酸聚合中至关重要.
- 设计具有量身定制的电子和硬质性能的催化剂是提高性能的关键.
- 异构复合体为催化剂设计提供了一种独特的方法.
研究的目的:
- 合成和表征新型异构合的哈夫复合物.
- 评估它们在乙烯同聚合和乙烯/1-烯共聚合中的性能.
- 为了比较它们的催化活性和稳定性与相关的同质化类似物.
主要方法:
- 合成胺和胺和胺复合物.
- 准备异构复合物的直角反应策略.
- 在各种条件下进行烯酸 (共聚合) 试验.
- 聚合物产品的特性,包括分子量和热性能.
主要成果:
- 三种异构合的哈夫复合物 (Hf1/3,Hf2/3,Hf2/4) 已成功合成.
- 这些复合物在乙烯同聚合过程中表现出明显更高的活性和热稳定性,相比单聚合物和同聚合物类似物.
- Hf1/3 实现了 2.82 × 10^7 g 聚合物 (mol Hf) ^-1 h^-1 的活性,产生分子重量高达 100 万的聚乙烯.
- 在120°C的乙烯/1-烯共聚合中,异构复合物保持了优越的热稳定性和活性.
- 由于多种不同的异质联结构,观察到可调的共聚合能力.
结论:
- 异质化哈夫复合物代表了烯酸聚合物的催化剂的一个有前途的类别.
- 异质化策略增强了催化活性,热稳定性,并允许可调节的共聚合.
- 这种方法扩大了具有改进性能特征的多烯催化剂的范围.
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