Some plastic waste is invisible: Shampoo, laundry detergent, and other common products often use tiny capsules made of microplastic as an ingredient. Those capsules then wash down the drain and can pollute waterways. A startup spun out of the University of Cambridge wants to replace those capsules—and other plastics that are hard or impossible to recycle—with a plant-based material that can easily dissolve.
The new material mimics spider silk, one of the strongest natural materials, on a molecular level. “The molecules in spider silk are bound together very tightly even though the interactions themselves are very weak,” says Tuomas Knowles, a chemistry professor at the University of Cambridge and one of the authors of a new paper in Nature Communications about the research. “The way that nature manages to do that is by arranging them in a regular pattern.”
The scientists developed a new process to dissolve plant-based protein in the right conditions so it forms into a similar structure. The process uses little energy, and can use sustainable ingredients; in the study, the team used soy protein isolate, a by-product of making soybean oil. Other plant-based materials that often end up as waste could also be used.