Study On Flame Retardant And Smoke Suppression Effect Of Modified Intumescent Fire Retardant Coatings

The traditional intumescent flame-retardant system has the disadvantage of poor dispersibility in the coating,and the expanded fire-retardant coating can generate a large amount of smoke in the process of expanding and foaming the flame-retardant,aiming at the above disadvantages,The new type of intumescent flame-retardant coating is prepared by compounding different flame-retardant smoke-suppressing agent and modified expansion flame-retardant system,and the flame-retardant and smoke-suppressing effect on the wood board is explored,and the flame-retardant smoke-suppressing effect on the wood is of great significance.And the silane coupling agent is used for carrying out the Fourier transform infrared spectrum and the X-ray diffraction characterization on the product of the surface modification of the polyphosphoric acid solution,and the result proves that the modification is successful.The products of Mg(NO3)2·6H2O and Al(NO3)3·9H2O co-precipitated were subjected to Fourier transform infrared and X-ray diffraction.The results showed that the magnesium-aluminum hydrotalcite was successfully prepared.Zinc borate and the prepared hydrotalcite were subjected to ion exchange reaction,and the product was subjected to Fourier transform infrared and X-ray diffraction.The results show that the hydrotalcite has completed the interlayer modification.The intumescent flame retardant system of the intumescent fire retardant coating is composed of modified ammonium polyphosphate pentaerythritol and melamine.Zinc borate hydrotalcite and modified hydrotalcite are selected as flame retardant and smoke suppressant respectively.The flame retardancy,thermal stability,thermokinetic parameters,smoke release performance and the carbon layer structure after combustion of fire retardant coatings were analyzed.The results showed that the flame retardant coating with 18 phr of zinc borate had the best flame retardant and smoke suppression effect.The equilibrium temperature was 125 C,the smoke density grade was 34.2%,and the residual mass after pyrolysis was 45%.The apparent activation energy and frequency factor are 27.82 kJ·mol-1 and 0.18103min-1,respectively,the height of expanded carbon layer is 17 mm.When the addition of hydrotalcite is 10 phr,the flame retardant and smoke suppression effect of the flame retardant coating is the best.The equilibrium temperature is 123 C,the smoke density grade is 21.4%,and the residual mass after pyrolysis was 42%.the apparent activation energy and frequency factor are 35.55 kJ·mol-1 and 0.65×103min-1,respectively,and the height of expanded carbon layer is 15 mm.When the content of modified hydrotalcite is 10 phr,the flame retardant and smoke suppression effect of the flame retardant coating is the best.The equilibrium temperature is 120?,the smoke density grade is 29.7%,the residual mass after pyrolysis is 44%,the equilibrium temperature is 120?,the smoke density grade is 29.7%,the residual mass after pyrolysis is 44%.The apparent activation energy and frequency factor are 31.93 kJ·mol-1 and 0.38×103min-1,respectively;the height of expanded carbon layer is 20 mm.Among the three intumescent fire retardant coatings prepared above,zinc borate additive fire retardant coating has the slowest pyrolysis process,hydrotalcite additive fire retardant coating has the best smoke suppression effect,and modified hydrotalcite additive fire retardant coating has the best flame retardant effect.Figure[37]table[17]reference[75]...