一种稳定的 (III) 催化剂,用于在空气下对循环无水化物/环氧化物进行环开交替共聚化
Wei-Cheng Ou1, Zhi-Kai Shen1, Man Wang1
1National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory for Nanotechnology, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China.
Inorganic chemistry
|October 2, 2025
概括
一种新的催化剂使环开放共聚化 (ROCOP) 的高效环开放共聚化 (ROCOP) 的环氧化物和无水化物产生高质量的聚. 这种方法在温和条件下可以控制分子量和选择性,简化了聚合物合成.
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:
- 环开合聚合 (ROCOP) 是合成聚的关键.
- 现有的催化剂往往缺乏活性和选择性,限制了聚生产.
- 开发高效的催化剂对于具有可控性质的高分子量聚合物至关重要.
研究的目的:
- 为了合成和表征一种新的稳定于空气中的 (III) 化物复合物.
- 评估其在环氧化物和无水化物的共聚化中的催化性能.
- 为了实现高分子量聚合物的受控合成,具有狭窄的分子量分布.
主要方法:
- 一个Cr(III) 化物复合物的合成和表征:[Cr(L) Cl2]Cl,L = 2,2'-([2,2'-二二胺]-6,6'-二) 双-2-ol).
- 氧化物 (PO) 与酸盐 (SA) 或酸盐 (PA) 的催化环开放共聚化 (ROCOP) 使用Cr (III) 复合物和 (PPN) Cl共催化剂.
- 分析聚的特性,包括分子重量,分子重量分布和结选择性.
主要成果:
- 在温和条件下,Cr (III) 复合物有效催化ROCOP.
- 得到了具有高分子量 (Mn高达61kDa) 和狭窄分布 (Đ <1.2) 的完美交替的聚合物.
- 获得了链的高选择性 (>99%) 和高循环无水化物转化率.
- 该过程表现出强度,耐受未净化的单体和环境大气,即使在低催化剂负载下.
结论:
- 开发的Cr(III) 催化剂在通过ROCOP合成精确定义的聚合物方面非常有效.
- 催化系统提供了实用优势,包括温和的条件和对杂质的耐受性.
- 这项工作促进了对具有受控微观结构的聚合成有效催化剂的开发.
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