双核启动器用于弹性聚烯聚烯的远程合成
Robert C Coffin1, Yanika Schneider, Edward J Kramer
1Department of Chemistry & Biochemistry, Mitsubishi Chemical Center for Advanced Materials, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|September 15, 2010
概括
新型双核复合物使准活体乙烯聚合成为可能,产生具有较高分子量的聚合物. 这种方法促进了先进的聚乙烯共聚合物的创造,具有独特的弹性质和更好的性能.
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
- 材料科学 材料科学 材料科学
背景情况:
- 开发先进的聚合催化剂对于创建具有定制性质的新材料至关重要.
- 基于的催化剂在烯酸聚合过程中表现有前途,但对聚合物结构的精确控制仍然是一个挑战.
研究的目的:
- 合成和表征用于乙烯聚合的新型双核复合物.
- 研究这些复合物的潜力,以生产高分子量聚乙烯和先进的共聚合物.
- 探索合成的聚合物和共聚合物的结构性质关系.
主要方法:
- 双核复合物的合成,由一个 bis () 片段连接在一起.
- 乙烯聚合利用双核复合体与 bis ((1,5-环氧八) (Ni (((COD)) ((2)) 激活的乙烯聚合.
- 使用原子转移基聚合 (ATRP) 制备伪三区块和伪五区块聚乙烯共聚物.
- 通过ATRP将n-丁烯烯酸移植到聚乙烯宏发起器上,以创建弹性聚合物共聚合物.
- 使用应力-张力试验对聚合物特性进行表征.
主要成果:
- 双核复合物以一种准生物的方式聚合乙烯,产生与单核系统相比大约两倍分子重量的聚合物.
- 伪triblock和伪pentablock聚乙烯共聚合物已成功合成,结合半晶乙烯丰富的末端块.
- 通过接种n-丁烯酸来获得具有弹性质的共聚物,在断裂时表现出很大的应变 (1600-2000%) 和出色的弹性恢复 (∼80%).
结论:
- 双核复合体在受控乙烯聚合方面比单核系统具有显著的优势,使得分子重量更高.
- 这些双核复合体所促进的远程聚合机制是创建先进的聚乙烯架构和功能性共聚合物的关键.
- 合成的共聚合物具有理想的弹性质,证明了这种方法在开发高性能材料方面的潜力.
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