Preparation Of Modified Phenolic/polyurethane Foam And Study On Flame Retardant And Smoke Suppression Properties

Polyurethane foam（PUF）and phenolic foam（PF）are widely used in building insulation materials because of their performance and advantages in low thermal conductivity,good weather resistance,good dimensional stability and convenient construction.However,PUF is extremely flammable in the air,and a large amount of toxic smoke will be generated during the combustion process,causing harm to the environment and life and health.In recent years,fire accidents caused by the burning of PUF have caused huge casualties and property losses,which has aroused widespread concern.PF has a high flame retardant efficiency due to the body structure formed by the crosslinking of a large number of benzene ring structures in the foaming process.However,the presence of cross-linked structure and rigid groups makes the mechanical properties of PF poor,mainly manifested in low compression and bending strength,high powdering rate and so on.（1）PUP and H₃BO₃ were introduced into phenolic foam through organic-inorganic co-modification,respectively,to study the effects of PUP and H₃BO₃ on the flame retardant performance,mechanical properties,micro cell structure and pulverization rate of PF composite foam.The results show that,compared with the pure sample,when the amount of PUP added is 8wt%,PFPUP8 has the highest mechanical properties,small cells and uniform structure,and the pulverization rate is reduced by 80%.This shows that the introduction of PUP increases the toughness of PF syntactic foam.In addition,the introduction of H₃BO₃ significantly improved the flame retardant and smoke suppression properties of the foam.This is mainly due to the barrier effect of B2O3 produced by H₃BO₃ in the endothermic process of combustion and decomposition.（2）A simple and highly efficient water-soluble phenolic/ZIF-67 composite flame retardant coating was designed and deposited on flexible polyurethane foam（FPUF）by LBL technology.The effects of assembly layers on the thermal stability,flame retardancy and smoke suppression performance of FPUF were studied.The coated components were characterized by FTIR,UV-vis and SEM,and the results proved the successful assembly of the coating.The construction of WSPR/ZIF-67 flame retardant coating reduces the PHRR,THR and smoke release of FPUF;at the same time,it suppresses the phenomenon of foam droplets during the combustion stage.TG-IR results show that the coating can effectively delay the escape time and reduce the content of gaseous toxic products during pyrolysis.（3）BPF and Si-gol were successfully coated on the surface of rigid polyurethane foam（RPUF）by surface brushing to prepare flame retardant and smoke suppression RPUF.The coated components were characterized by FTIR and TG.The flame retardant test results showed that the combination of BPR and Si-gol exhibited a higher flame retardant efficiency under the same coating amount compared to a single control sample.Heat release and smoke volume are significantly reduced.Figure[45]table[16]reference[122]...