Water-based intumescent fire resistance coating containing organic-modified glass fiber for steel structure

Fire resistance of steel structures is crucial to building safety to maintain structural integrity and avoid secondary damage (building collapse), when facing fire hazards. High temperature in fire rapidly softens the steel structure which fails to afford the load bearing. Water-based intumescent coating is now one of the most prospective treatments as it is excellent fire resistant, environmentally friendly, and economically effective. However, the poor density and thermal stability of its char residue make it difficult to be competent in a real fire. In this work, an organic-modified glass fiber grafted with 10-(2, 5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide and γ-(2, 3-epoxypropoxy) propyltrimethoxysilane (ODOPB@KH560@GF) was prepared as the filler for the intumescent fire-resistant coating containing ammonium polyphosphate/melamine/pentaerythritol (APP/MEL/PER) and water-based acrylic latex. The ODOPB@KH560@GF was found to enhance the thermal stability of the char layer and decrease the peak heat release rate and total heat release by 60.5 % and 58.8 % in a dosage of 5 wt % (AL-4). Also, the fire resistance limit of the steel plate coated with AL-4 was twice as high as that of the unprotected steel plate and higher than that of the steel plate coated with the commercial one, leading to further applications in the fire safety coating for steel structures.