State Key Laboratory of Power System, Department of Electrical Engineering, Tsinghua University, Beijing 100084, China.
ACS Appl Mater Interfaces. 2023 Mar 1;15(8):11185-11192. doi: 10.1021/acsami.3c00520. Epub 2023 Feb 16.
Dielectric polymers are playing important roles in electrical and electronic industries. However, aging under high electric stress is a main threat to the reliability of polymers. In this work, we demonstrate a self-healing method for electrical tree damage based on radical chain polymerization, which is initiated by radicals that are generated during electrical aging. Acrylate monomers contained in microcapsules will be released and flow into hollow channels after the capsules are punctured by electrical trees. Autonomous radical polymerization of the monomers will heal the damaged regions, which is triggered by radicals resulting from polymer chain scissions. After optimizing the healing agent compositions by evaluating their polymerization rate and dielectric properties, the fabricated self-healing epoxy resins showed effective recovery from treeing in multiple aging-healing cycles. We also expect the great potential of this method to heal tree defects autonomously without the need to switch off operating voltages. This novel self-healing strategy will shed light on building smart dielectric polymers with its broad applicability and online healing competence.
电介质聚合物在电气和电子工业中起着重要的作用。然而，在高电场应力下老化是聚合物可靠性的主要威胁。在这项工作中，我们展示了一种基于自由基链式聚合的电树枝损伤自修复方法，该方法由电老化过程中产生的自由基引发。电树枝击穿微胶囊后，胶囊内的丙烯酸酯单体将被释放并流入中空通道。单体的自主自由基聚合将修复受损区域，这是由聚合物链断裂产生的自由基引发的。通过评估聚合速率和介电性能对愈合剂成分进行优化后，制备的自修复环氧树脂在多次老化-愈合循环中表现出了有效的电树枝恢复能力。我们还期望这种方法能够在无需切断工作电压的情况下，自主修复电树枝缺陷，具有很大的应用潜力。这种新颖的自修复策略将为具有广泛适用性和在线修复能力的智能电介质聚合物的构建提供思路。
