Development of Sustainable Biodegradable Polymers from Renewable Resources for Industrial Applications

Abstract

With the increasing reliance by modern industry on petroleum-based plastics has come significant environmental problems, such as landfill refuse, marine pollution and greenhouse gases. The present paper focuses on an integrated experimental and techno-economic study on sustainable biodegradable polymeric materials prepared from renewable raw materials and compared with conventional fossil based polymeric materials like polyethylene terephthalate (PET). The physical properties (tensile strength, elongation, modulus, impact resistance), thermal transitions, decomposition behavior and biodegradation kinetics for eight representative systems (polylactic acid, polyhydroxyalkanoates, starch-based blends, cellulose acetate, polybutylene succinate, bio-based polyethylene terephthalate, castor oil-based polyurethane, and lignin-based epoxy) were determined for soil burial, composting, marine, freshwater, and anaerobic digestion environments. The global market of industrial applications (packaging, agriculture, medical, textile, automotive, electronics, additive manufacturing) was surveyed, and a parallel techno-economic and life-cycle assessment quantified the conversion yield, production cost, energy demand, water consumption, land footprint and the greenhouse gas emissions generated during the conversion of each feedstock route. Results indicate polylactic acid and bio-based polyethylene terephthalate as having the best tensile properties that are close to fossil polyethylene terephthalate; polyhydroxyalkanoates and starch-based blends show significant biodegradability and environmental performance with applicability for short-service-life applications. A comparative index normalized by the PET of fossil origin shows that for all the metrics considered to date, no single biopolymer performs better than PET from fossil origin, which indicates the importance of judicious material selection for the application. These results provide quantitative support for trade-offs in the transition towards renewable and biodegradable polymer platforms and future scenarios of hybridization for researchers and industrial players.