Enhancement effect of acylated cellulose nanocrystals on waterborne polyurethane

In this work, A new composite material composed of cellulose nanocrystals (CNCs) and waterborne polyurethane (WPU) was prepared. The thermal stability and mechanical properties of composites were studied. Compared with composites with CNCs without acylation treatment, the composites with modified CNCs by acylation reagents exhibited better thermal stability and mechanical properties. In addition, CNCs modified by butyric anhydride in composites demonstrated excellent mechanical properties. When 1.00% of CNCs modified by butyric anhydride were added to WPU, the fracture stress of the resulting composite material reached 52.15 MPa, which was 1262% higher than that of WPU (3.81 MPa), and 157% higher than that of the composite 1% CNCs without acylation treatment (20.31 MPa). This preparation of CNCs-WPU composites with better performance on thermal and mechanical properties provides guidelines for further improving the application of WPU.