The novel resin can be used for a variety of other applications. The team produced cultured stone, by mixing the resin with different minerals, that could be transformed into household objects such as countertops and sinks. “We’ve recently made a bathroom sink with the cultured stone, so we know it works,” said Dorgan. The recovered material can also be crushed and mixed with other plastic resins for injection molding, which is used to make laptop covers and power tools.
The material could even be upcycled into higher-value products. Digesting the thermoplastic resin in an alkaline solution released poly(methyl methacrylate) (PMMA), a common acrylic material for windows, car taillights, and many other items.
When the temperature of the digestion converted PMMA was raised, it formed into poly(methacrylic acid), a super-absorbent polymer that is used in diapers. Interestingly, the alkaline digestion also produced potassium lactate, which can be purified and made into candy and sports drinks. “We recovered food-grade potassium lactate and used it to make gummy bear candies, which I ate,” Dorgan said.
Next, the researchers hope to make some moderately sized blades for field testing. “The current limitation is that there’s not enough of the bioplastic that we’re using to satisfy this market, so there needs to be considerable production volume brought online if we’re going to actually start making wind turbines out of these materials,” Dorgan said.
Dorgan added that there is no ‘yuck’ factor in eating candy that was once part of an old wind turbine. “A carbon atom derived from a plant, like corn or grass, is no different from a carbon atom that came from fossil fuel. It’s all part of the global carbon cycle, and we’ve shown that we can go from biomass in the field to durable plastic materials and back to foodstuffs,” he said.