The Polymer Society of Korea

Abstract

Recent advances in circular polymer design have largely focused on fused-rings with heteroatom intermonomer linkages such as C-O, C-S, and C-N bonds. In this presentation, we demonstrate that thermally depolymerizable polymers with all-carbon backbones can be rationally designed by selectively weakening intermonomer C-C bonds. We first introduce experimentally identified structures, discussing their characterization and depolymerization behavior with emphasis on bond dissociation energies. Building on this, a systematic DFT investigation of butadiene-based repeat units reveals that radical stabilization through β-unsaturation, lone-pair donation, and hyperconjugation is the dominant factor governing C-C bond cleavability. Experimental validation confirms that simple polybutadiene analogs can achieve near-quantitative monomer recovery at practical temperatures. Together, the results establish a general framework for designing circular polymers based on tunable C-C bond energetics.