在这种情况下,高效的终端功能化聚二烯由环氧化合物通过介介导的协调链转移聚合物化
Xiuhui Zhang1, Jing Dong2, Feng Wang1
1Shandong Provincial College Laboratory of Rubber Material and Engineering/Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China.
Polymers
|September 28, 2024
概括
这项研究引入了一种有效的方法,用于在协调链转移聚合 (CCTP) 中使用环氧化合物来终端功能化聚二烯. 这种技术实现了高的功能化效率,模仿天然结构.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
背景情况:
- 新介导的协调链转移聚合 (CCTP) 是用于二烯合成的先进方法.
- CCTP产生反应性Al覆盖的聚乙烯链末端,用于终端功能化.
- 通过终端功能化模仿天然结构是关键目标.
研究的目的:
- 开发一种有效的现场方法,用于最终功能化聚二烯.
- 将环氧化物化合物引入用于聚合物修饰的CCTP系统.
- 探索Al覆盖聚乙烯链末的潜力,以创建功能性聚合物.
主要方法:
- 使用新 (Nd) 催化剂的二烯的协调链转移聚合 (CCTP).
- 在现场将环氧化物化合物引入聚合系统.
- 使用1H NMR,1H,1H-COSY NMR,DOSY NMR和MALDI TOF质谱法进行表征.
- 密度函数理论 (DFT) 计算以确定环氧环开放的能量障碍.
主要成果:
- 实现了高端功能化效率为92.7%的聚烯.
- 证实在链末部引入多达两个乙烯氧化物 (EO) 装置.
- 通过DFT.发现了EO单体环通过DFT.打开时的33.3kcal/mol的能量屏障.
- 观察到功能化效率从92.7%降至74.2%,因粘度增加而增加[Ip]/[Nd]比率.
- 证明了末端基组易于转化为其他功能.
结论:
- 通过CCTP和环氧化物成功开发了一种有效的现场方法,通过CCTP和环氧化物终端功能化聚二烯.
- 该方法允许对功能组进行受控的引入,模仿天然.
- 聚合条件,例如[Ip]/[Nd]比,影响功能化效率.
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