New material from crab shells and plants could replace nylon bags

Cellulose is extracted from plants. Meanwhile, chitin is found in many animals with exoskeletons (shells) such as crabs, shrimps, insects or inside mushrooms.

The team suspended chitin nanofibers and cellulose nanocrystalsinside an aqueous environment (suspension), then spraying the solution onto a surface in multiple layers and drying, creating a material that is durable, flexible, pliable, transparent and biodegradable. The new material is very durable because the chitin nanofibers are positively charged while the cellulose nanocrystals are negatively charged, and the two opposite poles attract each other.

Comparisons show that the new material is also much more airtight than PET plastic - an industrial plastic used in the production of packaging, bottles, and food containers. "The material we created shows 67% better oxygen resistance than PET plastic, so in theory, this material can keep food fresher for longer.",Meredith said.

An estimated 322 million tons of plastic are produced worldwide each year. Much of it is discarded after use and eventually washed into the oceans, causing serious harm to marine life. New biomaterials made from chitin and cellulose are a promising solution to combat plastic pollution in the future.

The scientists say the new material needs further refinement before it can be produced on a large scale. In addition to gas permeability, the team also wants to improve the material’s moisture resistance. The research was published in the American Chemical Society’s Journal of Sustainable Chemistry and Engineering.