Thermostability and flame retardance of green functional two-component waterborne polyurethane coatings with nanoparticles

A new kind of green and functional two-component flame-retardant waterborne polyurethane and its coating were synthesized through adding polyurethane polyol dispersions, hydrophilic nanoTiO 2 and hydrophilic curing agent. The properties and analysis were characterized via FTIR, laser particle analyzer, rheometer, TEM, TGA, TGA-FTIR, LOI tester, SEM, UV–vis spectrum, water and solvent resistance. The results showed the tensile strength counld reach 22.3 MPa. And the nanoTiO 2 delayed speed of thermal decomposition to improve thermostability of two-component waterborne polyurethane. Larger quantities of hydrophilic nanoTiO 2 did not produce a larger unbroken carbon yield surface or thicker carbon layers, but effectively produced a condensed phase flame-retardant effect with OP550 during burning. Besides, LOI and UL-94 also reached over 29.4% and V–0 respectively. The UV and visible light shielding noticeably increased with the adding nanoTiO 2 . The 0.5% content of nanoTiO 2 had the optimal properties in green and functional two-component waterborne polyurethane coatings.