EAGER: CAS: Recyclable Polystyrene-Substitutes through On-demand Depolymerization

点击翻译按钮获取中文摘要

NON-TECHNICAL SUMMARY:The overall goal of this research is to establish recyclable thermoplastics that are based on polystyrene-substitute materials since plastics made of polystyrene itself are not commonly recycled. Polymers are an essential material class used in nearly all modern products. However, most of the used polymer products are landfilled, improperly discarded, or incinerated and thus have environmental consequences. The high-cost problem of polymer recycling suggests the desirability to develop new polymers with low-cost and facile recyclability without compromising physical properties needed for practical applications. This research aims to establish a new class of recyclable thermoplastics that can effectively substitute polystyrene. Polystyrene is one of the largest produced thermoplastic polymers used as a key component for numerous commodity and specialty applications. However, polystyrene has been barely recycled due to high cost. The proposed research will replace non-recyclable polystyrene with new high-performance thermoplastics that can be recycled from used products at low cost. This research will significantly benefit society by establishing polystyrene-substituting recyclable thermoplastics that could remedy the environmental problems caused by polystyrene wastes. The planned work also includes educational activities for K-12 and undergraduate students to enhance their exposure and understanding of STEM fields with a focus on polymers and materials structures. TECHNICAL SUMMARY:The planned research aims to establish and study recyclable thermoplastic polymers as polystyrene substitutes through implementing low-cost and facile depolymerizability. The depolymerizability will be achieved by copolymerizing monomer with a low-ceiling temperature and other monomer that controls the properties of polymers. A library of recyclable copolymers will be synthesized, depolymerization characteristics of the polymer library will be studied, and optical and viscoelastic properties of the copolymers will be characterized for evaluation of the new polymers as polystyrene substitutes and beyond. These efforts will establish the correlations between the chemical composition of the copolymers and the physical/depolymerization properties. The established correlations of recyclable copolymers will serve as the design criteria of polymers for target applications. The project will provide graduate and undergraduate students with broad research training on polymers ranging from synthesis to characterization and materials properties..This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.