Four interdisciplinary graduate student teams investigated greener alternatives to hazardous chemicals and unsustainable plastic products. Final presentations and reports are included for each project below.
6PPD in Tires
In early 2021, 6PPD-quinone, which is a transformation product of 6PPD, was discovered as the likely cause of pre-spawn mortality in Coho salmon in the Pacific Northwest. 6PPD is a critical tire rubber additive with high-performing antidegradant properties. The team proposed four strategies: the use of food preservatives, such as gallates; replacement with the polymer lignin; modification of 6PPD to prevent formation of its toxic quinone form; and finally, broader process-level changes, including adjustments to vulcanization processes schemes and rubber formulation.
PFAS in Floor Polishes
This team examined potential alternatives to PFAS (per- and polyfluoroalkyl substances) in floor polish, in response to recent legislation in Maine requiring the removal of PFAS from “avoidable” use in products sold in the state by 2030. Floor polish is under consideration as one possible product category since nearly every floor polish on the market contains PFAS. The team proposed two biosurfactants as potential alternatives to PFAS in floor polish: rhamnolipids and amino acid surfactants, specifically sodium lauroyl glutamate.
Compostable Packaging for Frozen Kelp
This team partnered with Noble Ocean Farms, a kelp farming startup in Cordova, Alaska, to identify sustainable and biodegradable packaging strategies. Their first strategy completely replaces polyethylene with a bioplastic, which is significantly less persistent in the environment. Their second strategy uses a durable material (i.e. paperboard) in combination with a bioplastic laminate/coating, eliminating traditional plastics completely. And their third strategy combines a bioplastic packaging with a structural material separate from the bioplastic.
Compostable Adhesive for PLU Stickers
This team was challenged with identifying biodegradable pressure sensitive adhesives for home-compostable price lookup (PLU) stickers. The team’s proposed alternatives include: proteins (gluten, Nb-1R, Arabinogalactan Proteins), polysaccharides (chitosan and carrageenan), biolipids (PHAs, Epoxidized Soybean Oil), and structural adhesives. The breadth of strategies explored provide excellent context, inspiration, and potential alternatives for the future of greener pressure sensitive adhesives.