Study On Preparation And Performance Of Self Expanding Flame Retardant Epoxy Resin Based Fire Retardant And Anti-Corrosion Coating

Steel structure has the characteristics of light weight,toughness and good earthquake resistance,and is widely used in beams,columns,trusses and other components of buildings.However,poor fire resistance and easy corrosion of steel structure will lead to economic losses and sometimes even casualties.The common method to improve its fire resistance and corrosion resistance is to apply anticorrosive coating and fire retardant coating respectively on the surface of steel structure,and there is no fire retardant coating with anticorrosive function at present.Therefore,in view of the shortcoming of single function of fire retardant coating,this paper studied the preparation of self-expanding flame retardant epoxy resin based fire retardant anticorrosive coating and its fire and anticorrosive performance.The results are as follows:（1）A new type of self-expanding flame retardant epoxy resin based fire retardant coating was prepared by using epoxy resin E51 as film forming material,ammonium polyphosphate（APP）6/Cu₂O4 as expansion flame retardant system,graphene（Gr）,nano-Si O₂ or magnesium aluminum hydrotalcite（HT）as anti-corrosion filler.The results show that:when the film substance is 60wt%,the film forming performance is good for Gr with the addition of no more than 2.0wt%,for nano-Si O₂ with the addition of no more than 2.0wt%,and for HT with the addition of no more than 5.0wt%.（2）The fire performance of self-expanding flame retardant epoxy resin based fire retardant anticorrosive coating was studied.The results show that:For the self-expanding flame retardant epoxy resin based fire retardant coating（IFR）without anti-corrosion filler,its back fire temperature reached 400℃in the 650s,for the IFR with anti-corrosion filler,when the addition amount of Gr,Si O₂ and HT is 0.5wt%,1.0wt%and 1.0wt%respectively,the fire performance of the anti-fire coating is the best.The back fire temperatures in the 1800s are249.6°C,252.6°C,and 306.0°C.In addition,the effects of Gr,Si O₂ and HT on the fire behavior of self-expanding fire retardant epoxy resin based fire retardant coating were studied by cone calorimetry from three aspects of heat release behavior,smoke production behavior and smoke toxicity.The addition of 0.5wt%Gr,1.0wt%Si O₂ and 1.0wt%HT did not reduce the fire safety of self-expanding fire-retardant epoxy resin based anti-corrosion coatings,that is,0.5wt%Gr/IFR,1.0wt%Si O₂/IFR and 1.0wt%HT/IFR had better fire safety performance.（3）The anticorrosion performance of self-expanding flame retardant epoxy resin based fire retardant anticorrosion coating was studied by testing the contact Angle,water absorption,salt water resistance and electrochemical performance.The results of contact Angle test and water absorption test showed that the addition of Gr,nano-Si O₂ and HT could improve the water resistance of IFR.The results show that the addition of Gr,nano-Si O₂ and HT can improve the salt water corrosion resistance of IFR.Electrochemical test results show that:The addition of Gr,nano-Si O₂ and HT filler can improve the electrochemical corrosion resistance of IFR,and IFR has the best corrosion resistance when 1.0wt%Si O₂ is added.Compared with IFR coating,the impedance modulus is increased by one order of magnitude from1919.11Ω·cm² to 16468.79Ω·cm².