Study On Weather Resistance Optimization And Anti-Aging Performance Of Intumescent Flame Retardant Coatings

Intumescent flame retardant coatings can effectively improve the fire safety performance of materials,fundamentally curb the spread of fire,and reduce the occurrence of major fire accidents.However,most traditional intumescent flame retardant coatings still have shortcomings such as strong water absorption,poor compatibility,and poor dispersion.During use,they are exposed to the combined effects of environmental factors such as ultraviolet radiation and humidity,and heat cycles,which not only affect the durability of the coating but also Its flame retardant performance is significantly reduced,becoming a potential safety hazard,limiting its and service life.In this paper,ammonium polyphosphate,urea,cyclodextrin,waterborne polyurethane resin,and polyacrylamide are used as the basic formula of intumescent flame retardant coating.In this formula,silicone oil and aluminum-titanium composite coupling agents are added to enhance the hydrophobicity of the coating,and white carbon black and nano zinc oxide are introduced as flame retardant synergists and ultraviolet absorbers to improve the anti-aging performance of the coating.Anti-aging intumescent flame retardant coating（Z-IFRC）was prepared by sol-gel method and coated on wood plywood according to the coating method specified by the national standard.Finally,flame retardant composite material Z-IFRC-W was prepared.The Z-IFRC-W was subjected to artificially accelerated aging test（ultraviolet radiation,xenon lamp radiation,and high and low temperature damp-heat alternating environment）,and then the aged Z-IFRC-W was subjected to CONE test,SEM test,TG analysis,pyrolysis kinetics analysis,XRD analysis,compressive strength test,and water contact angle test to study the influence of aging environment on the comprehensive properties of composite materials.Studies have shown that in the basic formulation of traditional intumescent flame retardant coatings,0.5 wt%of silicone oil,0.8 wt%of white carbon black,2.0 wt%of nano-zinc oxide,and aluminum-titanium composite coupling agent of type 125 are selected.The intumescent flame-retardant coating prepared by the formula has the best flame-retardant performance.The results of the CONE test show that the p HRR of Z-IFRC-W increased by101%,88%,and 102%after UV aging,xenon lamp aging,and high-temperature damp-heat alternating aging.The composite material without nano-zinc oxide（IFRC-W）p HRR increased by 125%,92%,and 112%,respectively.The smoke production,CO₂release,and oxygen consumption of the two composite materials gradually increased with the increase of aging time,which proved that the fire safety performance of the composite materials decreased.Through the SEM test,it is observed that the compactness and integrity of the carbon layer of the aging composite material gradually decrease,but the microstructure integrity of Z-IFRC-W is better than that of IFRC-W,which proves that nano-zinc oxide can improve the aging resistance of the flame-retardant composite material.Through TG analysis,it is found that ultraviolet aging and xenon lamp aging make the thermal stability and carbon residue rate of the composite material gradually decrease.The decrease in apparent activation energy E proves that the thermal decomposition rate is accelerated.At the same time,the XRD pattern shows that the amorphous substance content of the material has also decreased.By testing the compressive strain force of the composite material after burning,it is known that when the deformation amount is 30mm,the Z-IFRC-W maximum strain force of the composite material after ultraviolet radiation,xenon lamp radiation,and high and low temperature damp heat alternating aging is reduced by 76%,51%and 59%,the maximum strain force of IFRC-W was reduced by 73%,59%,and 65%,respectively.The water contact angle test shows that the water contact angles of Z-IFRC-W after ultraviolet radiation,xenon lamp radiation and high and low temperature damp heat alternating aging are reduced by 31%,32%,and 42%,respectively.The water contact angles of IFRC-W are reduced by 31%,32%,and 42%,respectively.A reduction of 36%,38%,and 44%.In summary,the anti-aging flame-retardant composite material Z-IFRC-W prepared in this paper has higher fire safety than IFRC-W,and nano-zinc oxide has better UV radiation resistance,reducing the flame retardancy of the aging composite material Loss of performance and mechanical properties.The composite materials were subjected to the same length of the aging test in three aging environments,and the order of the degree of influence of the three aging environments on the comprehensive performance of the composite material was as follows:ultraviolet aging influence degree>high and low-temperature humidity and heat alternating environmental influence degree>xenon lamp The degree of aging influence is of great significance for the subsequent development of weather-resistant and efficient IFRC and to further improve the fire safety of flame retardant materials.