Human beings are intrinsic to the global carbon cycle so economic circularity will require unbiased interconversion of carbon between materials, fuels, and food. In this work, a recyclable polymer resin suitable for composites manufacturing that can be partially converted into an edible food ingredient is demonstrated. Present generation plastics and composites have concerning sustainability metrics including high embedded energy and associated greenhouse gas emissions, low recyclability rates, and generation of microplastics pollution. Long fiber composite materials are notoriously difficult to recycle but are critical for wind turbine, lightweight vehicle, and other sustainable technologies. An economically viable, fully recyclable, composite resin consisting of biobased polylactide (PLA) dissolved in methyl methacrylate (MMA) is demonstrated. Physical properties of thermoplastic composites produced from the reclaimed resin show true “turbine-to-turbine” recycling is possible. Various end-of-use options are established; regrinding of thermoplastic composites produces short fiber moldable materials. Base catalyzed digestion of either thermoplastic or thermosetting resins produces poly(methyl methacrylate) or the superabsorbent poly(methacrylic acid). Distillation of the digestate produces methanol, water, and food grade potassium lactate; the resulting lactate has been incorporated into gummy bear candies and consumed by the presenting author. Judicious formulation of polymer resins enables complete circularity in low-embedded energy materials; exploitation of triggerable degradation provides varied and intriguing end-of-use recycling options.

Composite resins for the circular economy: From wind turbines to gummy bear candy and beyond

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.