Ultra-tough, transparent, adhesive, and biocompatible silanized nanocellulose reinforced high bio-based content waterborne polyurethane composites.

A waterborne polyurethane with high bio-based content and excellent mechanical properties has been developed to promote global sustainable development and respond to the call for environmental protection. In this paper, a bio-based polyurethane (GWPU) was prepared from bio-based diisocyanate and bio-based polyol. The MCNF nonreinforcement modified by a 3-Aminopropyltriethoxysilane coupling agent (APTES) was introduced. The GWPUM nanocomposites exhibited remarkable mechanical properties (fracture stress 73.14 MPa, elongation at break 1538 %, and toughness 285.2 MJ/m3). In addition, GWPUM has notable transparency, thermal stability, and water resistance. Furthermore, it displays excellent adhesion and self-healing properties induced by ethanol. Its outstanding biocompatibility provides a promising option for the application of waterborne polyurethane in the biomedical materials and coating sector.