Mechanical and Thermal Properties of Waterborne Polyurethane Films Modified by CaCO 3 @TiO 2 Particles with UV Absorption Activity

CaCO3@TiO2 particles were synthesized through a direct carbonation method, which can be used as the substitutes of TiO2 in pigments and coatings. To improve the dispersion in waterborne polyurethane(WPU) suspensions, CaCO3@TiO2 particles were modified by stearic acid. SEM tests of the fractured surfaces of the composites films showed that the CaCO3@TiO2 particles were well embedded in the WPU matrix. And the mechanical properties, thermal stability and water resistance of the composites films were improved by the introduction of CaCO3@TiO2 particles.