Study On The Regularity And Flame Retardant Mechanism Of Nano-ATH Modified Finishing Fire-retardant Coating

At present,the flammable and combustible polymer materials are used in all kinds of buildings more and more widely,which resulting in fire frequently and often major fires.It is extensive used method of fire protection that is application of fire retardant coatings for building substrates.In this paper,taking the water-borne intumescent fire retardant coatings for research objects,add the nano aluminum hydroxide flame retardant with different particle size and amount to the basic fire retardant coating,in order to study the effect of nano-ATH on fire retardant coating and the flame retardant mechanism.The study includes: 1)Confirmed the basic formula components firstly,then optimizing the basic formulation of fire retardant coating by orthogonal test design.2)Add the nano-ATH flame retardant with different particle size and amount to the basic fire retardant coating,and test and analyze the physical and chemical properties and combustion properties of the coating samples.3)Through the method of SEM analysis,FTIR analysis to research the expanded carbonaceous layers after pyrolysis,analyzed the pyrolysis process of the fire-retardant coatings by the method of TGA analysis,and study the effects of nano-ATH flame retardant on the fire-retardant coatings and the flame retardant mechanism based on the experimental results.Now get the following conclusion:Based on the formulations of basic fire-retardant coating,use()49L3 orthogonal design method to optimize the emulsion and the intumescent flame retardant system.The influence of the four factors on the performance of fire retardant coatings is by the range of: APP > PER > Polyacrylate emulsion > MEL.Get the coating formulations which has the optimum flame retardant effect combine with the test results of ignition time.Under the condition of the radiation intensity is 302/mk W and the temperature is at the temperature of 625 DEG C,the ignition time of the optimal fire-retardant coating is about 605 s.The physical and chemical performance test and combustion test are implemented on the basic fire-retardant coating and fire-retardant coatings with nano-ATH.Combining with the experimental results,we can conclude that the performance of flame retardancy of the fire-retardant coating which add the amount of less than 9% and MZ= 100 nm ATH is best.The SEM-EDX analysis shows that the expanded carbonaceous layer of fire-retardant coating which add the amount of 3% and MZ= 100 nm ATH has the most ideal alveolate structure.Through out the FTIR analysis we can get that the strong absorption asymmetric stretching vibration peaks of Si-O-Al are appeared at the band of 1300-1cm ~1450-1cm in the expanded carbonaceous layers of 20-2,50-5 and 100-1.All of these promote the formation of the expanded carbon layers,which indicated that the nano-ATH played an important role in the fire-retardant effect and can enhance the flame retardant effect.From the TGA-DSC analysis we can see,the fire-retardant coatings with nano-ATH are superior to 8# fire-retardant coatings in terms of pyrolysis temperature,pyrolysis time and the amount of carbon residue.These results are in agreement with the results obtained by cone calorimeter tests,and it can illustrate that the addition of nano ATH can improve the flame retardant effect,which the dehydration temperature and heat absorption are related to the particle size,content and heating conditions.