Advances in liquid phase transmission electron microscopy (LP‐TEM) have enabled the monitoring of polymer dynamics in solution at the nanoscale, but radiolytic damage during LP‐TEM imaging limits its routine use in polymer science. This study focuses on understanding, mimicking, and mitigating radiolytic damage observed in functional polymers in LP‐TEM. It is quantitatively demonstrated how polymer damage occurs across all conceivable (LP‐)TEM environments, and the key characteristics and differences between polymer degradation in water vapor and liquid water are elucidated. Importantly, it is shown that the hydroxyl radical‐rich environment in LP‐TEM can be approximated by UV light irradiation in the presence of hydrogen peroxide, allowing the use of bulk techniques to probe damage at the polymer chain level. Finally, the protective effects of commonly used hydroxyl radical scavengers are compared, revealing that the effectiveness of graphene's protection is distance‐dependent. The work provides detailed methodological guidance and establishes a baseline for polymer degradation in LP‐TEM, paving the way for future research on nanoscale tracking of shape transitions and drug encapsulation of polymer assemblies in solution.

中文翻译：

---

在液相透射电子显微镜下理解、模拟和减轻聚合物的放射分解损伤


液相透射电子显微镜 （LP-TEM） 的进步使得在纳米尺度上监测溶液中的聚合物动力学成为可能，但 LP-TEM 成像过程中的放射损伤限制了其在聚合物科学中的常规使用。本研究的重点是理解、模拟和减轻在 LP-TEM 中功能性聚合物中观察到的放射分解损伤。定量证明了聚合物损伤在所有可能的 （LP‐）TEM 环境中是如何发生的，并阐明了聚合物在水蒸气和液态水中降解的关键特征和差异。重要的是，研究表明，在过氧化氢存在下，LP-TEM 中富含羟基自由基的环境可以通过紫外光照射来近似，从而允许使用体技术在聚合物链水平上探测损伤。最后，比较了常用羟基自由基清除剂的保护作用，揭示了石墨烯的保护效果与距离有关。这项工作提供了详细的方法指导，并为 LP-TEM 中的聚合物降解建立了基线，为未来研究纳米级形状转变和溶液中聚合物组装体的药物封装铺平了道路。