Chemical Upcycling of Polyphenylene Sulfide at Room Temperature

Polyphenylene sulfide (PPS) is a semi-crystalline super engineering plastic with exceptional chemical resistance, thermal stability, and mechanical integrity. The rapidly growing consumption of PPS underscores an urgent demand for sustainable recycling strategies to promote circularity in the PPS industry. Chemical upcycling offers a compelling and sustainable strategy for plastic waste valorization. Herein, an efficient iron-photocatalyzed chemical upcycling of PPS plastics with 1,2-dichloroethane at room temperature is reported, affording recuperative chlorinated arylene monomer and valuable chloroacetic acid. Mechanistic investigation demonstrates chlorinated phenylthiyl species as the key intermediates generated from chlorine radical to mediate aryl C─S bond cleavage. The protocol establishes broad compatibility of eighteen commercial PPS resins and composite waste with gram-scaled efficiency and effective degradation for mixed-plastic matrix, offering a transformative paradigm for super engineering plastic upcycling.