化α-胺预催化剂,产生具有改善机械性能和控制晶度的聚乙烯
Aoqian Xi1,2, Qiuyue Zhang2, Yanning Zeng1
1College of Materials Science and Engineering, Guilin University of Technology, Qixing District, Guilin 541004, China.
ACS omega
|August 11, 2025
概括
新的复合物与化 iminoacenaphthylene 连接物催化乙烯聚合,产生具有可调节机械性能的高晶体聚乙烯. 这为新型热塑性弹性体提供了潜力.
科学领域:
- 协调化学 协调化学
- 聚合物科学 聚合物科学
- 催化剂是一种催化剂.
背景情况:
- 开发高效的乙烯聚合催化剂对于生产先进的多聚烯至关重要.
- α-Diimine催化剂以乙烯聚合而闻名,但往往表现出链路行走行为,导致分支聚合物.
- 需要催化剂,可以精确控制聚合物微观结构和特性.
研究的目的:
- 合成和表征新型的正形/准化N-----------氨酸乙联体及其相应的复合物.
- 评估这些复合体在乙烯聚合中的催化性能.
- 研究连接物结构,聚合条件和产生的聚乙烯的特性之间的关系.
主要方法:
- 化伊米诺乙烯联体 (L1-L6) 和它们的复合物 (Ni1-Ni6) 的合成.
- 使用NMR,FT-IR,EA和单晶X射线衍射对有机配体和复合物的表征.
- 乙烯聚合研究使用复合物与乙烯化 (EASC) 激活.
- 聚乙烯微结构 (晶性,多分散性,分子量) 和机械性能 (拉伸强度,破裂时延伸,弹性回收) 的分析.
主要成果:
- 尼基复合物Ni1-Ni6已成功合成和表征.
- 所有复合物都在乙烯聚合过程中表现出高的催化活性 (4.737.9 × 10^6 g mol^-1 h^-1),其中Ni1是最活跃的.
- 催化剂在广泛的温度范围 (40~70°C) 上表现出极好的热稳定性.
- 由此产生的聚乙烯具有高结晶性 (6.462.6%),窄多分散性 (1.82.9),中等分子重量,长链分支最小.
- 实现了可调整的机械性能,代表性样本显示出高拉伸强度 (13.1 MPa) 和破裂时的延伸 (1030.6%).
结论:
- 新型复合物是乙烯聚合物的高度活性和热稳定的催化剂.
- 催化剂系统允许精确控制聚乙烯晶度和机械性能,偏离典型的链路行走行为.
- 生产的聚乙烯具有适用于作为热塑性弹性体的应用的特性.
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