Environmental reliability is a quite important requirement for ionic conductive adhesives (ICAs) that determines the long-term durability of the bonding systems. However, little is known about the environmental reliability and failure mechanism of ICAs. In this study, four kinds of ICAs are prepared via physical blending of epoxy resin, polyethylene glycol diglycidyl ether (PEGDE) and ionic liquids (ILs). The environmental reliability of ICAs are presented through monitoring the bonding strength during aging treatment under 55 °C and 95% relative humidity. It is found that the introduction of ILs significantly deteriorates the environmental reliability and the size of the ILs shows remarkable influences on the environmental reliability. The investigation of the failure mechanism reveals the ILs migrate to the bonding substrates and enrich at the interfaces, which increases the free volume of the interfacial polymers and reduces the cohesive strength of ICAs, thus the interactions between ICAs and bonding substrates are destroyed. It is believed that this work provides a comprehensive understanding to long-term durability and the failure mechanism of the physical blended ionic conductive materials.

环境可靠性是离子导电粘合剂 (ICA) 的一项非常重要的要求，它决定了粘合系统的长期耐用性。然而，人们对 ICA 的环境可靠性和失效机制知之甚少。本研究通过环氧树脂、聚乙二醇二缩水甘油醚(PEGDE)和离子液体（IL）。ICA的环境可靠性通过监测55℃和95%相对湿度下老化处理过程中的结合强度来呈现。研究发现，ILs的引入显着恶化了环境可靠性，并且ILs的大小对环境可靠性具有显着影响。失效机理的研究表明，ILs迁移到粘结基材并在界面处富集，这增加了界面聚合物的自由体积并降低了ICA的内聚强度，从而破坏了ICA与粘结基材之间的相互作用。据信，这项工作提供了对物理共混离子导电材料的长期耐久性和失效机制的全面理解。