Preparation And Properties Of Fire-Retardant And Anti-Corrosion Ultra-Thin Expansion Coating For Steel Structure

Modern buildings structure is still the main material using steel, concrete and glass. Steel has high strength, stable performance and good toughness and it is suitable for mass production, which make steel become the best building structural materials. But there are two invisible hazard in the application process of steel structures:not fire retardant and easy corrosion. Low refractory performance and corrosive can lead to large casualties and huge economic losses. Normally, taking coatings protection is one of the most economical and the most effective protection method. Usually fire and corrosion resistant of steel structure are treated independently. Namely we use anti-corrosion coatings to protect corrosion, and use fire protection coatings to resist fire. This protection method maybe appear that fire layer peels off which make film lost fire prevention effect in the application process. In addition, besmearing multi-layer coatings process is various in construction, that not only leads to increase VOC, but also wastes resources and leads to environmental pollution. This subject explores a kind of fire prevention and anticorrosion properties of the new technology with the paint recipe, and considers the coatings’fireproof performance, anti-permeability, corrosion resistant performance.This paper studies the fire anti-corrosion coatings’film material, expansion system,the kind of pigments and fillers and content size and the relationship between the coating. properties. Experimental results found that use organic silicon mondified acrylic resin, matching with fireproof performance P-N-C expansion system, plusing expansible graphite collaborative expansion foaming, we can produce fire coatings of excellent fireproof performance. By means of small room combustion method test, We found that this film’s refractory limit is 98min.And the impedance of film is 5*10Ω·cm.The anticorrosion performance of P-N-C expansion system is limited that cannot satisfy the needs of the project.Therefore, antirust pigment and functional padding were added to fire-retardant coating in this experiment. It was designed to greatly increase coating corrosion resistant capability and not affect fire resistance. Among common antirust pigment, we choose Aluminum Tripolyphosphate as the padding of system. Ac impedance and fire endurance testing results showed that has better penetration-proof quality and fire reststance when add 6.8%Aluminum Tripolyphosphate. Through adding the functional padding such as mica powder, ceramic powder, kaolin and nano-silicon dioxide, it can be observed that ceramic powder and nano-silicon dioxide can more improve film density. When their additive amount was 10.2% and 1.1% respectively, coating impedance could reach 3.6* 109Ω·cm2, which showed excellent penetration-proof quality. Meanwhile, coating medium showed excellent chemical resistance, fire endurance was improved markedly, reach 120min when the coatings’thickness is 1.5mm.The results of comprehensive test show that the coating’s adhesion is 1-2 levels, impact resistant is 50 kg.cm, flexibility is level 1, penetration-proof quality in 1099Ω·cm2 above, excellent soaking performance in resisting chemical medium. This shows that this coating system has excellent fireproof performance, at the same time, it has excellent anti-corrosion properties, this excellent performance paint’s construction is convenient, which offeres a solution for large steel structure of the fire and corrosion protection.