在空间定义的有机基聚合物中的电荷转移
Ting Ma1, Evan Fox2, Miao Qi1,2
1Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States.
Chemistry of materials : a publication of the American Chemical Society
|February 15, 2024
概括
使用ADMET聚合和TEMPO的后功能化合成空间定义的基聚合物可以增强电荷转移. 控制激素间距可以提高聚合物的灵活性和包装,从而显著加快氧化还原反应动力学.
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
- 电化学 电化学 电化学
背景情况:
- 非结合的氧化还原活性聚合物中的电荷转移是复杂的,受氧化还原点的近距离和聚合物灵活性的影响.
- 独立研究这些因素一直是了解聚合物电荷传输机制的一个重大挑战.
研究的目的:
- 合成空间定义的含有基的聚合物,独立研究氧化还原点间隔和聚合物灵活性对电荷转移的影响.
- 建立聚合物特性 (例如,玻璃过渡温度,链条灵活性) 和电荷转移动力学之间的相关性.
主要方法:
- 亚环二烯转化 (ADMET) 聚合被用来制造具有激活基的α,ω-二烯.
- 用4-amino-TEMPO进行后聚合功能化,在聚合物骨干沿着控制的间隔 (9,11,15,21) 引入稳定的氧化基单位.
- 包括差分扫描热度计 (DSC),分子动力学 (MD) 模拟和电化学研究在内的技术被用于描述聚合物特性和电荷转移.
主要成果:
- 空间定义的TEMPO替代聚合物表现出减少的旋转-旋转合和增加的链灵活性与更大的根间距.
- 玻璃过渡温度 (Tg) 从47.6到-13.8°C不等,与根间距相关.
- 15碳间隔的聚合物显示Tg最低,跳跃距离最短,电荷转移动力学比PTAm快1000倍,扩散和动力学与Tg有很强的相关性.
结论:
- 控制聚合物骨干沿线的氧化还原活性组间距对于调整骨干灵活性和激素包装至关重要.
- 这些结构修改导致非结合的氧化还原活性聚合物的电荷转移动力学的协同改进.
- 该研究表明,聚合物Tg和电荷转移效率之间存在明显的关系,为设计先进的氧化还原活性聚合物提供了一条途径.
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