活水微乳液聚合乙烯与坚固的Ni (II) 基化催化剂
Fei Lin1, Tobias O Morgen1, Stefan Mecking1
1Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany.
Journal of the American Chemical Society
|December 1, 2021
概括
新的催化剂使活乙烯聚合成为可能,产生在水中分布狭窄的超高分子量聚乙烯. 这一突破减少了链接转移,促进了水性介质中的聚合物合成.
科学领域:
- 聚合物化学
- 有机金属化学
- 材料科学
背景情况:
- 使用P,O-化Ni (II) 复合物的乙烯聚合通常会导致低分子量聚合物,这是由于相互竞争的链转移事件.
- 在聚合催化中,实现具有受控结构的高分子量聚合物仍然是一个挑战.
研究的目的:
- 开发一种用于生物乙烯聚合的新催化剂系统.
- 在水环境中研究生产超高分子量聚乙烯的潜力.
- 克服与传统聚合方法中的链传输相关的局限性.
主要方法:
- 大量的替代酸复合物的合成和表征.
- 使用合成复合物的微乳液 (催化剂3) 来水性聚合乙烯.
- 聚合物分子重量分布 (Mw/Mn) 和分子重量 (高达2 × 10^6) 的分析.
主要成果:
- 开发的氨酸 (Ni) 复合物 (3) 显示出活体聚合的行为,显著减少了链转移.
- 具有超高分子量 (高达2×10^6) 和狭窄的分子量分布 (Mw/Mn=1.021.34) 的聚乙烯已成功生产.
- 聚合在水性纳米粒子分散中进行,催化剂保持稳定性和活性至70°C.
结论:
- 大量的基酸复合物是水中活乙烯聚合的有效催化剂.
- 这种方法可以合成超高分子量聚乙烯,并精确控制分子量分布.
- 催化剂在水性环境中的稳定性和活性为可持续和高效的聚合物生产开辟了道路.
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