Study On The Retardant Function Of Wood-plastic Composites Coated With Silicone Flame Retardants

Wood-plastic composite materials (WPC) get more and more attention from people, and the high performance is becoming more and more important. There are many applications needing the flame retardant requirements, so that it is a hot pot to study the flame retardant requirements of WPC in order to reduce the fire danger and maintain cheap, environmental protection in the field.This paper studies the four aspects:①the influence of the glue coating made with layer silicate and acrylic resin at high speed to the flame retardancy of WPC;②the influence of the coating prepared with organic silicon and organic silicone modified epoxy at high speed to the flame retardancy of WPC;③the test uses infrared thermal to analysis the structure characterization of silicone flame retardant coating blending with different assisting element before and after burning, and the thermal stability of various components are studied by the thermo gravimetric analysis, and then its flame retardant mechanism is analyzed;④the experiment determines the best content of flame retardant formulation silicon coating and analyzes the flame retardant mechanism.We can get the following conclusion after analyzing the experimental test results:(1) The good formula of the inorganic silicone flame retardant coating is got through single factor experiment; it is thought that the flame retardant mechanism of silicate is not only dilution effect and dehydration effect, but also its expansion effect. While being strongly hot, it will form continuous barriers to block and insulate heat and oxygen in order to realize its flame retardant efficacy. The coating could have two kinds of structure, one is a molecular chain of resin inserting in slice layer structure of silicate. The other one is stripping silicate into matrix dispersion resins.(2) Orthogonal analysis can conclude that the organic silicon M - 01 has the biggest influence to refractory time index; it is thought that the flame retardant mechanism of silicon oxygen radicals is including condensed-phase flame retardant mechanism. Namely it achieves its flame retardant through generating the cracking carbon layer and improving oxidation resistance of carbon layer.(3) The test can conclude that the Flame retardant time of the silicone coating blended with different assisting element all has significantly improved; among with them the coating blending with pentaerythritol is the most significant. It forms density carbon layer structure, having the porous and closed pore state, forming foam body skin to make the gas not escape.(4) The physico-chemical properties and flame retardant performances of the flame retardant coating Which is used for wood-plastics composites finally determined can reach certain requirements, the decomposition of silicon flame retardant and the reaction producing gas of assisting element in flame retardant system is in the same temperature range, and it can generate density and formalization carbonized layers, having good function of heat insulation and oxygen barrier, preventing the burning continuing effectively.