Wang Feng, Burck Michal, Diesendruck Charles E
Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Haifa, 32000, Israel.
ACS Macro Lett. 2017 Jan 17;6(1):42-45. doi: 10.1021/acsmacrolett.6b00874. Epub 2016 Dec 23.
The mechanochemical stability of a polymer is a fundamental parameter when choosing the ideal material for many different uses where mechanical loading may induce molecular weight reduction. The use of mechanophores has significantly improved the detection of mechanochemical reaction, but their incorporation to different polymers can be synthetically challenging. Alternatively, we return to the old strategy of using spin traps to quantify the radicals produced as a consequence of mechanochemical homolytic bond scission events. Several new spin traps have been developed in recent decades, and pyrenyl nitrones have been shown to effectively bind radicals, providing a spectroscopic methodology to follow radical concentration. Here we demonstrate the use of these probes as excellent tools to follow mechanochemical chain scission.
对于许多不同用途而言，在选择理想材料时，聚合物的机械化学稳定性是一个基本参数，因为在这些应用中机械负载可能会导致分子量降低。机械力发色团的使用显著改善了机械化学反应的检测，但将它们引入不同聚合物在合成方面可能具有挑战性。作为替代方案，我们回归到使用自旋捕获剂来量化机械化学均裂断键事件产生的自由基这一古老策略。近几十年来已经开发了几种新型自旋捕获剂，并且已证明芘基硝酮能有效结合自由基，提供了一种跟踪自由基浓度的光谱方法。在这里，我们展示了这些探针作为跟踪机械化学链断裂的出色工具的用途。
