Frontiers of Chemical Science and Engineering
Preparation of lignin/TiO2 nanocomposites and their application in aqueous polyurethane coatings
|1. School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
2. State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
A simple method using a water soluble lignin quaternary ammonium salt (LQAS) and TiO has been developed for the preparation of lignin/TiO nanocomposites in an aqueous medium under mild conditions. The LQAS/TiO nanocomposites contain well-dispersed small particles with excellent ultraviolet (UV) shielding abilities and good compatibilities with waterborne polyurethane (WPU). When the LQAS/TiO nanocomposites were blended with WPU, the UV absorbance and the tensile ductility of the WPU increased significantly. The composite WPU hybrid film containing 6 wt-% LQAS/TiO nanocomposite had the highest visible light transmittance and had excellent ultraviolet aging properties. After 192 h of UV light irradiation, the tensile strength of the composite film was above 8 MPa and the elongation at break was 800%. This work highlights new possibilities for the utilization of alkali lignin.