通过形成铜超氧化物复合物的氧增强原子转移激素聚合
Kostas Parkatzidis1, Nghia P Truong1, Richard Whitfield1
1Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland.
Journal of the American Chemical Society
|January 10, 2023
概括
氧气通过一种新的ARGET-ATRP机制形成超氧化物种,从而意外地加快了受控的基质聚合. 这种方法提高了聚合率,并允许高分子量聚合物具有出色的控制,即使使用不纯的催化剂.
科学领域:
- 聚合物化学
- 催化剂
- 材料科学
背景情况:
- 氧气通常会抑制受控的激素聚合,导致链终结和催化剂失活.
- 现有的方法需要高度净化的催化剂和受控的环境来防止氧气干扰.
研究的目的:
- 研究氧气在原子转移基聚合 (ATRP) 中的作用.
- 开发一种新的ATRP机制,利用氧气提高聚合效率和控制.
主要方法:
- 使用超氧化物介导的原子转移基聚合 (ARGET-ATRP) 机制.
- 使用CuBr/合物复合物和各种单体.
- 使用质谱和尺寸排除色谱对聚合物进行表征.
主要成果:
- 氧会从CuBr/L中触发*in situ*反应性超氧化物种的形成,使得聚合率提高一个数量级.
- 在非常低的铜度 (4.5 ppm) 中,获得了高分子量聚合物 (DPn = 6400),具有良好的控制 (Đ < 1.20).
- 证明了高终端群忠实性,使单块和多块共聚合物的单合成具有近量化转换.
结论:
- 超氧化物ARGET-ATRP机制提供了可控激素聚合的强大而有效的方法.
- 该方法对催化剂杂质具有耐受性,减少了严格净化需求,降低了成本.
- 这种方法通过利用氧气作为有益的成分来扩大受控聚合的范围.
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