EFRI E3P: Program plastic lifecycle by rationally design enzyme-containing plastics

This project targets embedding active enzymes during plastic manufacturing, and programming on-demand plastic degradation or modification during product fabrication, storage, and use. The project's hypotheses are that (1) molecular control of biocatalysis within polymeric matrices can afford on-demand modification or programmable plastic degradation during manufacture, use, and disposal, and (2) with recent advances in synthetic biology and nanomaterial engineering, it is feasible to develop economically viable enzyme-embedded plastics to achieve valorization or degradation of end-of-life plastic waste.

The interdisciplinary project team seeks to develop compostable single-use plastic based on polymers with chemically labile backbones and valorization of polyolefins by C-H bond oxidation. The team intends to (1) develop approaches to manufacturing these materials at large scale using melt extrusion, (2) test properties of prototypes, and (3) evaluate the environmental impact of the prototypes with local ecology centers.

By engineering compostable plastics that are stable under conditions relevant to storage and use but degrade in a matter of days under composting conditions, this project seeks to provide basic knowledge of important relevance to the compostable single-use plastics industry. The intended outcome of the research would reduce the volume of single-use plastic packaging sent to landfills and reduce mechanical separation costs at organics processing and composting facilities.

The research plan is to (1) develop molecular understanding in biocatalysis of enzymes nanoscopically dispersed in semi- crystalline polyesters with focus on enzyme stability, catalytic mechanism, and kinetics to realize programmable degradation, (2) develop molecular understanding in biocatalysis in oxidase-containing polyolefins and design catalytic cascades to chemically modify sidechains of polyolefins for valorization and accelerated degradation, and (3) fabricate minimum viable prototypes, optimize the system for relevant commercial performance as single-use plastics, validate the material properties and performance using ASTM testing methodology, and perform technoeconomic analysis and evaluate prototype life cycle. It is anticipated that the work will provide significant insights in the emerging fields of solid-state enzymology and enzyme-containing functional materials.

The project team also plans a three-tiered approach aimed at improving undergraduate education in the area of polymer science, developing a polymer degradation kit for students and public demonstrations, and creating course modules to specifically highlight polymer recycling, upgrading, and enzymatic degradation. This award is co-funded by the directorate of Mathematical and Physical Sciences, specifically the Polymers Program in the Division of Materials Research.

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.