高分子量聚烯弹性体的合成 通过使用α-二胺催化剂的烯聚合
Lujie Gao1, Hegang Ren2, Yanhui Hou3
1Hebei Key Laboratory of Functional Polymers, Institute of Polymer Science and Engineering, Hebei University of Technology, Tianjin 300401, China.
Polymers
|August 29, 2024
概括
新的 ((II) 催化剂使得高分子量和透明度的无性聚烯弹性体的合成成为可能. 这些催化剂在高温下保持高活性,为先进的聚合物材料提供了有前途的途径.
科学领域:
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- α-二胺后期过渡金属催化剂提供了一种新的策略,用于合成无活性聚烯弹性体.
- 在高温下提高聚烯分子量和增加催化剂活性是关键的挑战.
研究的目的:
- 合成和评估用于聚合的新型α-二胺 (II) 催化剂.
- 研究催化剂结构对聚烯特性的影响,特别是分子量和弹性体特性.
主要方法:
- 两种α-二胺 () 催化剂与基甲基替代剂的合成.
- 在烯中使用合成的催化剂进行烯同聚合.
- 催化活性的表征,聚烯分子量,1,3链的含量,以及机械/光学性能.
主要成果:
- 最大催化活性达到5.40 × 10^5 gPP/molNi·h,在50°C时保持>10^5 gPP/molNi·h.
- 催化剂产生的聚烯具有高分子量 (4071101公斤/mol) 和低的1,3-链 (3.5716.96%) 由于抑制链路行走和转移.
- 由此产生的聚烯表现出弹性质的特性:拉伸强度低 (0.31.0 MPa),破裂时长度高 (218403%),延展恢复良好 (~50%),可见光透射率高达~90%.
结论:
- 开发的α-二胺 ((II) 催化剂有效地生产高分子量性聚烯弹性体.
- 催化剂结构的固体阻碍对于控制聚合物微观结构和实现所需的弹性体特性至关重要.
- 这些发现为合成具有可调节性质的透明聚烯弹性体提供了一种可行的方法.
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