August 2024: Reprocessible Electronic Substrates
With collaborators Prof. Chen Wang and Dr. Caleb Reese (University of Utah), we report photopatternable, performant and degradable polyimides for electronic substrate applications. Polyimides (PI) like Kapton®, are a ubiquitous material in electronic goods and thermal protection materials owing to the unique combination of outstanding mechanical, electrical, chemical, and thermal stability. Unfortunately, PI is infusible and insoluble which prevents direct fabrication of advanced 3D architectures. By synthesizing custom diallyl bisimide monomers, we reported photopolymerizable PI resins that require no additional post processing and possess superior properties compared to similar formulations. We demonstrate that our material is compatible with scalable electronics manufacture and is particularly beneficial for dense, multilayered circuits. Additionally, this material contained degradable ester linkages which allowed for complete depolymerization under mild conditions. By reprocessing the substrate (see below), we can recapture all of the conventional microelectronics of the circuit for reuse—an economically incentivized framework for reducing e-waste, a great societal challenge as our lives become increasing connected with technology.