Bio-inspired material to replace plastics

Modern life relies heavily on plastics, even though their petroleum-based production poses serious environmental challenges. The industry currently lacks sustainable alternatives due to their limited mechanical properties or complex manufacturing processes. An advanced strategy to design and produce durable high performance structural materials is therefore badly needed.

Such a new bio-inspired material is now available to replace petroleum-based plastics. A team led by Professor Shu-Hong Yu of the China University of Science and Technology (USTC) reports a method of making mother-of-pearl-like structural materials from wood-derived fibers and mica, with adaptation to mass production, good processability and tunable coloring.

Natural mother-of-pearl has a hierarchical structure at multi-scale levels, just like bricks and mortar, which allows it to be both strength and tenacity. Inspired by mother-of-pearl, researchers mimic orderly brick-and-mortar structure using TiO₂ coated mica chip (TiO₂-mica) and cellulose nanofiber (CNF) by the proposed directional strain assembly method.

This method directly presses the TiO hydrogel₂-mica and CNF, while keeping the size in the in-plane directions unchanged. The thickness of the hydrogel is greatly reduced and the materials are directly constructed with the very orderly brick and mortar structure.

At the nanoscale, TiO₂ nanograins on the surface of TiO₂-mica leads to efficient energy dissipation by friction sliding during TiO₂-mica pull-out. The whole hierarchical structure at several scales contributes to the redistribution of the load and the improvement of toughness.

The materials obtained have excellent strength (~ 281 MPa) and toughness (~ 11.5 MPa m1 / 2), which are more than 2 times higher than those of high performance engineering plastics (for example, polyamides, aromatic polycarbonate), which makes it a solid material. competitor of petroleum-based plastics.

Best of all, these materials adapt to temperatures ranging from -130 ° C to 250 ° C, while normal plastics easily soften at high temperatures. Therefore, these materials are safer and more reliable at high or varying temperatures.

Provided by China University of Science and Technology