Ultrathin expansion steel-structure fireproofing coating

Abstract

The present invention provides a fire-retardant coating capable of forming ultrathin coating layer and having high fire-resisting limit. Its composition comprises (by weight portion) 50-60 portions of modified acrylic resin, 12-16 portions of pentaerythritol, 9-12 portions of trimeric cyanamide, 19-21 portions of polyammonium phosphate, 6-8 portions of zinc borate, 9-11 portions of titanium pigment, 1.25-15 portions of chlorinated paraffin (in which chlorine content is 70%) and 8-15 portions of 200# solvent gasoline. The above-mentioned modified acrylic resin is a chlorinated rubber modified acrylic resin made up by using 1.4-1.8 portions of chlorinated rubber, 2.2-2.7 portions of xylene, 0.9-1.1 portions of hexamethylene-diisocyanate and 1.6-1.8 portions of hydroxyl-bearing acrylic resin. Its coating layer thickness is 1.71-2.69 mm, and its fire-resisting limit can be up to 69-147 min.

Description

technical field [0001] The invention relates to the technical field of coatings, in particular to ultra-thin intumescent fireproof coatings for steel structure buildings. Background technique [0002] At present, there are three types of widely used fireproof coatings for steel structures: thick type, thin type and ultra-thin type. The latter two are also called intumescent fire retardant coatings. In addition to the ingredients of general architectural coatings, it mainly contains carbonizing agents, foaming agents, catalysts, etc. of the expansion system. Under the high temperature of the flame, the coating undergoes complex physical and chemical changes and expands and foams, forming a A uniform and dense spongy carbonized layer that is dozens or even hundreds of times thicker than the original coating. This carbonized layer has a very low thermal conductivity, and its thermal conductivity is about 0.02W / (m·K)~0.05W / (m·K), which can effectively isolate the heating of th...

AI Technical Summary

Problems solved by technology

There are following problems: (1) its main film-forming substance is a modified acrylate resin emulsion, which is a water-based resin, and the formed coating film still has certain moisture absorption after drying, and powdering, Falling off and so on, thus losing its fire protection effect

(2) The ammonium phosphate in its expansion system has a negative effect on the water resistance and durability of the coating due to its high water solubility, which will affect the physical and chemical properties and fire resistance limit of the coating