Solvolytically debondable adhesive systems – potentials and challenges for repair and recycling

In the context of decarbonization initiatives, the repairability and recyclability of components have become a major concern in various industrial sectors, particularly for resource-intensive components. The development of innovative bonding and debonding processes that must adhere to the stringent mechanical specifications of the manufacturers and facilitate their efficient disassembly is a major issue faced in the implementation of a sustainable circular economy. Although adhesively bonded joints satisfy the stringent requirements for mechanical performance, they present several challenges during the repair and recycling process. Solvolytically debondable epoxy resin adhesives may be employed to overcome this issue. In this study, we aim to conduct an exploratory feasibility study on the application of such chemical debonding mechanisms within an adhesive bond as well as to systematically analyse and evaluate the suitability of such adhesive systems for various applications. To this end, we employed various thermo-analytical methods and quasi-static tensile tests to characterise the mechanical adhesive and joint properties of two solvolytically debondable adhesive systems. Furthermore, we analysed the debondability of the adhesive joints and evaluated their feasibility in an industrial environment. The results indicate considerable application potential for solvolytically debondable adhesives, along with further development steps currently required.