The heat resistance of a polyurethane coating filled with modified nano-CaCO_3

摘要

The modification of polyurethane coating by adding surface-modified CaCO_3 nanoparticles (nano-CaCO_3) was investigated in this paper. To improve interfacial interaction between the nano-CaCO_3 and the polyurethane (PU) matrix, a silane coupling agent (KH560) was used to modify the nano-CaCO_3. The grafting of KH560 on the nano-CaCO_3 surfaces was characterized by the TEM, FTIR and TGA techniques. The modification of the nano-CaCO_3 surfaces with KH560 was demonstrated to improve the dispersity of nano-CaCO_3. FTIR, SEM and AFM were used to characterize the polyurethane coating. The FTIR spectrum indicated that the modification of nano-CaCO_3 does not influence the chemical structure of the PU matrix. The roughness and gloss of the nanocomposite coatings containing various amount of nano-CaCO_3 were evaluated using a roughness tester and a brightness meter. The heat resistance of the polyurethane coating containing various amounts of nano-CaCO_3 was evaluated using the TGA technique. The results revealed that nano-CaCO_3 treatment with KH560 improves the nanoparticle dispersion and heat-resistance of polyurethane coating.