在恶劣条件下稳定和受控的聚合三碳酸盐链传递剂的稳定性和控制聚合
Thi Ngan Vu1, Tomoya Nishimura1, Yu Osaki2
1Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji 671-2280, Japan.
Polymers
|February 13, 2025
概括
这项研究表明,三碳酸链转移剂 (CTA) 在恶劣条件下具有不同的稳定性. 由于其疏水性组,Rtt-05更稳定,使N,N-二甲基甲胺的受控聚合成为可能,但不使2 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 甲基甲基氧乙基酸胆.
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
- 有机合成 有机合成
背景情况:
- 可逆添加碎片化链转移 (RAFT) 聚合是一种强大的技术,用于控制的激素聚合.
- 基于三碳酸盐的链传递剂 (CTA) 对RAFT至关重要,但它们在恶劣条件下的稳定性是一个关键问题.
- 设计具有定制性质的CTA对于特定的单体应用是必不可少的,特别是在水性介质中.
研究的目的:
- 评估两个三碳酸盐CTAs,Rtt-17和Rtt-05在恶劣条件下 (60°C,基本) 的稳定性.
- 评估Rtt-17和Rtt-05在RAFT聚合中对N,N-二甲基胺 (DMA) 和2 - 甲基氧) 乙烯酸 (MPC) 等水友性单体的性能.
- 了解影响CTA稳定性和聚合控制的结构属性关系.
主要方法:
- 在基本条件下,在60°C使用1HNMR和UV-VIS光谱测定Rtt-17和Rtt-05的稳定性评估.
- 使用Rtt-17和Rtt-05作为CTA的DMA和MPC的RAFT聚合.
- 使用凝透色谱分析聚合物分子重量分布 (Mw/Mn).
主要成果:
- 与Rtt-17相比,Rtt-05表现出优越的稳定性,这是由于其疏水型二基团的菌形成,保护了三碳酸盐部分.
- 无论是Rtt-17还是Rtt-05,都有效控制了DMA的聚合,产生了Mw/Mn<1.2的聚合物.
- Rtt-17控制了MPC聚合 (Mw/Mn ≈1.2),而Rtt-05失败 (Mw/Mn ≥1.9) 原因是菌形成破坏了CTA-单体相互作用.
结论:
- 在RAFT聚合中,CTA结构显著影响稳定性和性能,特别是在水友性单体中.
- 疏水性基团可以通过菌形成增强CTA在水性介质中的稳定性,但可以阻碍高度疏水性单体的聚合.
- 这些发现对于为生物医学和工业应用设计有效的CTA至关重要,这些应用需要精确控制水友性聚合物合成.
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