Preparation and characterization of well-dispersed waterborne polyurethane/CaCO_3 nanocomposites

摘要

In this study, in order to improve the dispersion and increase the compatibility between nanoparticles and waterborne polyurethane (WPU) matrix, CaCO_3 nanoparticles were firstly modified with oleic acid (OA). A series of WPU/CaCO_3 nanocomposites were prepared by further in situ polymerization. SEM examination of the fractured surfaces of nanocomposites showed that OA-CaCO_3 achieved well dispersion in WPU matrix. FTIR analysis suggested no major changes in the chemical structure of WPU in the presence of 2wt% CaCO_3. Thermal stability of WPU measured by TGA was greatly improved with the addition of OA-CaCO_3. Meanwhile, the mechanical properties of the nanocomposites, examined by tensile tests, showed higher tensile strength than that of the pure WPU, especially incorporation of OA-CaCO_3.