Development Of New Bio-grad Flame Retardant Synergist And Study On Flame Retardant And Smoke Suppressive Performance In EPDM

EPDM is a rubber material with excellent comprehensive properties.It is widely used in daily life and industrial production.The preparation of functional rubber materials with fire and flame retardant properties has high research value.Traditional flame retardants have the disadvantages of large addition,low flame retardant efficiency,and pollution to the environment.It is difficult to take into account the mechanical properties of rubber and its flame retardant properties.This article aims to improve the flame retardancy of EPDM rubber.Successfully designed and prepared a low-smoke,halogen-free,environmentally friendly intumescent flame retardant system,which was introduced into EPDM,and passed infrared spectroscopy(FT-IR),limiting oxygen index test(LOI),vertical combustion test(UL-94),Cone Calorimetric Test(CCT),Thermal Weight Loss Analysis(TGA),Scanning Electron Microscope(SEM),Raman Spectroscopy(Raman)and other technologies to perform performance and microstructure of flame retardant and flame retardant rubber composite materials Characterization.In this thesis,a new type of flame retardant synergist EGT was prepared using biological substrates Enteromorpha(EN)and graphene(GE)as raw materials,and flame retardant and reinforcement of EPDM were studied.A plant polyphenol monomer was used.Tannic acid(TA)is used as a dispersant for graphene to prepare TGE.The benzene ring structure in tannic acid and the sp~2 hybrid structure of graphene haveπ-πinteractions,so that graphene can be stably dispersed in the liquid phase.The ultra-fine process physically modifies Enteromorpha and reduces its particle size to improve its interface with the rubber matrix.EGT is used as a reinforcing filler and auxiliary flame retardant to make the two rubber composite materials of NR and EPDM stretch.Tensile strength increased by 11.49%and 16.47%,respectively,LOI increased by 16.2%and9.1%,respectively.EGT flame retardant improved the flame retardant and physical and mechanical properties of EPDM.EGT is compounded with phosphorus-based flame retardants ammonium polyphosphate(APP)and piperazine pyrophosphate(PPAP)to form a new type of biologically intumescent flame retardant system AEG and PEG,and explore the resistance of AEG and PEG to EPDM The combustion performance is affected.EGT,which has good thermal stability and high charring ability,is used as the"carbon source"in the intumescent flame retardant system.When the mass ratio of the main flame retardant APP or PPAP to EGT is 40:21.1,the two types of flame retardants The combustible agent can achieve a synergistic effect to achieve the best flame retardant ratio.The two intumescent flame retardant systems reduced the PHRR of EPDM by 57.7%and 55.9%,and the TSP by 30.1%and 34.9%,respectively.The final carbon residue after combustion increased by 6.6%and 19.6%.EGT would migrate to The surface of the material plays a role in promoting carbon formation,and an expanded carbon layer with mass insulation and heat insulation is formed in the condensed phase to inhibit the combustion of the polymer matrix.This new intumescent flame retardant system exerts the phosphorus-nitrogen synergistic flame retardant effect.Make EPDM have better flame retardancy.The sepiolite group has good thermal stability and adsorption performance,and can be used to strengthen and toughen rubber and plastic materials and improve the flame retardancy.K-SEP is prepared by surface modification of the sepiolite by the silane coupling agent KH550,And used it as a flame retardant and smoke suppressant to be compounded with AEG and PEG into flame retardants AEGS and PEGS with smoke suppression effect,and added to EPDM to discuss the thermal stability and flame retardancy of composite materials EPDM/AEGS and EPDM/PEGS Smoke suppression and mechanical properties.When the addition amount of sepiolite is 3%,the AEGS and PEGS flame retardant systems can make the LOI of EPDM reach 33.7%and 32%,respectively,and the vertical combustion test can reach the V-0 level.The calorimetric test data shows that the THR of the sepiolite component composite material decreased by 13.5%and 16.6%,and the SPR decreased by 26.3%and 14.3%,respectively.Through the SEM and Raman test data of the carbon slag after combustion Through analysis,it was found that sepiolite has the flame retardant effect of suppressing smoke release,and a small amount of sepiolite improves the mechanical properties of EPDM.