Preparation of nanocellulose and application of nanocellulose polyurethane composites.

Polyurethane is a widely used material because of its excellent properties. Cellulose is a renewable, biocompatible, and biodegradable natural polymer that also has the advantages of a low density, high porosity, and large specific surface area. There are three main types of common nanocellulose: nanocellulose fibers, cellulose nanocrystals, and bacterial nanocellulose. Composites prepared with nanocellulose and polyurethane materials have good mechanical properties and good biocompatibility and can be applied in sensors, 3D printing, self-repairing materials, electromagnetic shielding, and many other areas. This paper details the preparation processes of different nanocelluloses and the application areas of composites, and points to the future development of nanocellulose polyurethane composites.