Development Of Silicone-acrylate And Epoxy Emulsion Compound Ultrathin Steel Structure Fire-retardant Coatings

Ultra thin steel structure fire retardant coating with high efficiency,convenient construction,good decoration and other advantages,has been widely used.At present,the application of ultra thin steel structure fire retardant coating has poor weathering resistance,low bond strength between the expansion layer and the substrate,and the flame retardant time is short and so on.Weatherability silicone acrylate emulsion with high content of silicon,the silicon content of silicone acrylic emulsion with low silicone monomer and acrylate copolymer is more easily in the hydrolysis of self polymerization.Epoxy emulsion has good adhesion to steel,sepiolite as inorganic flame retardant,flame retardant performance and environmental protection.The optimized formulation and process of high silicon content silicone acrylate emulsion were studied.The structure and thermal stability of the film were characterized by IR and TG.The silicon acrylic latex and epoxy emulsion as base material,P-N-C system for flame retardant system,expandable graphite and sepiolite as flame retardant synergistic agent for preparation of fireproof coating,and the vertical burning method,DSC-TGA and SEM methods of fire retardant coatings for fire resistance,thermal degradation and charring layer structure are analyzed and the optimized result is obtained.The results show that the silicon content of silicone acrylic emulsion prepared with acrylic monomers for the calculation of quality accounted for 15%,the emulsion properties to meet the GB/T 20623-2006 with emulsion building coating requirements,and has good weatherability.Fourier transform infrared spectroscopy on the resin showed that the organic silicon was successfully grafted onto the acrylic resin molecules.The thermogravimetric analysis showed that the weight loss rate of the coating was 7.029% in 300?,and the thermal stability of the silicone acrylic varnish was good.Using self-made silicone acrylate emulsion with epoxy emulsion as base material,coating of expandable graphite and sepiolite as flame retardant synergistic agent preparation,when pigment/binder ratio was 3:1,silicon acrylic latex and epoxy emulsion ratio is 2:1,the flame retardant system in the dosage of ammonium polyphosphate,melamine,pentaerythritol 12.5%?9%?12% expansion P-C-N,fire retardant synergistic agent of sepiolite and expandable graphite dosage was 3% when the fire preparation with physico chemical and fire resistant properties of the best coating,expansion of uniform and high carbonization layer dense,high strength,fire resistance time reached 73.25 min.Thermal analysis shows that the coating has good thermal stability in the range of 200~800?.SEM of the charring layer structure showed that the synergistic effect of sepiolite,EG improved carbon layer structure.The development of water and environmental protection fireproof coating for steel structure,comprehensive test results showed that the performance indexes meet the requirements of GB14907-2002,the light aging resistance,adhesion,water resistance,freeze-thaw stability and other indicators better than the national standard requirements,effectively solve the coating bonding strength,weather resistance problem.