Enhancing the flame-retardant and smoke suppression properties of transparent intumescent fire-retardant coatings by introducing boric acid as synergistic agent

摘要: A series of novel phosphorus-boron flame retardants (BPEAs) were successfully synthesized by introducing boric acid (BA) into cyclic phosphate ester (PEA) via the esterification and thoroughly characterized 1H nuclear magnetic resonance spectroscopy Fourier transform infrared (FTIR) spectroscopy. Five kinds transparent fire-retardant coatings applied to wood substrates produced mixing amino resin with PEA BPEAs. The effects BA on optical transparency, thermal stability, fire performance smoke emission characteristics investigated various analytical instruments. transparency analysis reveals that value gradually decreases increasing loading, MPEA4 highest content still exhibits a high degree transparency. results from protection, cone calorimeter density tests show introduction greatly spread rating, mass loss, char index, heat release rate, production total release, specific concomitant increase in residual intumescent factor, which is ascribed formation more dense continuous judging digital photographs scanning electron microscope images. Thermo-gravimetric indicates onset decomposition temperature, high-temperature stability improve content. FTIR shows contributes generate phosphorus-rich cross-linked structures aromatic then create compact layer, thereby effectively enhancing retardancy suppression properties coatings.