Mechanistic study of polymerization-retarding impurities toward full circular economy of polystyrene
발표자
하유진 (인하대학교)
연구책임자
김희중 (인하대학교)
초록
내용
Polystyrene (PS) is a widely used plastic with low recycling rates, raising environmental concerns. Catalytic depolymerization of PS yields a styrenic liquid (SL), mainly styrene, offering a route to a circular economy. However, impurities in SL hinder repolymerization and lower molar mass. Here, we investigated structure–reactivity relationships in SL and identified benzyl-containing molecules and α-substituted styrenes that interfere with polymerization via chain transfer or thermodynamic effects. These impurities were removed by distillation, yielding distilled SL with ∼92% styrene. Its polymerization gave high-molar-mass PS (up to 150kDa), with thermal and mechanical properties comparable to virgin PS. Furthermore, depolymerization of repolymerized PS showed consistent behavior, supporting the feasibility of a closed-loop PS recycling system. This work offers insights into impurity effects and proposes practical solutions for scalable and sustainable PS recycling.