甲基甲酸盐的质子转移阳离子聚合与分子重量和战术性双重控制的配体
Katsutoshi Sagawa1, Mineto Uchiyama1, Hironobu Watanabe1
1Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Precision chemistry
|December 30, 2024
概括
这项研究证明了使用质子转移阳离子聚合 (PTAP) 对聚甲基酸 (PMMA) 特性的双重控制. 干精确调整战术性,而可逆终端控制分子重量,使得立体块PMMA合成.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 质子转移阳离子聚合 (PTAP) 为受控聚合物合成提供了一条途径.
- 调整聚合物如聚甲酸 (PMMA) 的战术性和分子量对于定制材料性能至关重要.
- 在PTAP中同时控制战术性和分子量仍然是一个挑战.
研究的目的:
- 研究甲基甲酸盐 (MMA) 在PTAP中对分子量和战术性的双重控制.
- 探索各种连接体对PMMA战术性的影响.
- 为了实现立体块PMMA的受控合成.
主要方法:
- 在0°C时利用了MMA在烯中的质子转移阳离子聚合 (PTAP).
- 采用了一种庞大的基催化剂和一种具有弱酸性C-H键的休眠物种.
- 研究了不同配体 (18-皇冠-6,奇拉 bis(oxazoline)) 对聚合物战术性的影响.
- 加入了1,1-二乙醇作为分子体重控制的可逆终止剂.
- 合成的立体块PMMA使用连续PTAP与宏发起者/宏链传递剂 (CTA) 方法.
主要成果:
- 没有配体合成的PMMA几乎是无动态的 (rr/mr/mm=22/54/24).
- 18-皇冠-6连接体促进的综合毒性PMMA (rr ≈ 58%).
- 基拉尔双氧) 配体产生了略有异性丰富的PMMA (mm ≈ 32%).
- 通过使用1,1-二乙醇,通过低分散度 (Đ = 1.1-1.2) 实现了分子量控制.
- 立体块PMMA与触动性和触动性细分成功合成.
结论:
- 干在控制PTAP期间的PMMA战术中发挥着关键作用.
- 可逆终端器允许精确的分子重量控制,而不会影响战术性.
- 序列式PTAP为合成高级聚合物架构,如立体块PMMA提供了一个可行的途径.
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