Synergistic Effect Of Bromine Antimony Flame Retardant And Its Flame Retardancy In Polypropylene Materials

Polypropylene,as one of the world's five general-purpose plastics,has good mechanical properties and chemical stability,and excellent processing performance.It is widely used in many fields.However,polypropylene is extremely flammable and has low oxygen.This non-refractory property greatly limits the use of polypropylene in flammable environments.Therefore,a flame retardant needs to be added to the polypropylene to improve its flame retardancy.Commonly used flame retardants include inorganic flame retardants,intumescent flame retardants,and bromine-antimony flame retardants.The inorganic flame retardant has poor flame retardant effect on polypropylene,making the modified polypropylene flame retardant level up to v-2.Usually the added amount is above 60%,which will inevitably affect the mechanical properties of polypropylene.Intumescent flame retardant has good flame retardant effect on polypropylene,but the addition amount is also large and generally more than 20%.Since the intumescent flame retardant has poor compatibility with polypropylene,it affects the mechanical properties of polypropylene.The bromine-antimony flame retardant has good flame retarding effect on polypropylene and the amount of addition is small,which has little effect on the mechanical properties of polypropylene.Therefore,bromo-antimony flame retardant widely used in the market was selected to modify the flame retardancy of polypropylene.By comparing several commonly used brominated flame retardants on the market,the selectedbromine-basedflameretardantswereoctabromoetherand decabromodiphenylethane,which met Rosh standards and burnt without carcinogens.The main flame retardants of octabromoether and decabromodiphenylethane were studied respectively.Antimony trioxide was a synergistic flame retardant,magnesium hydroxide was inorganic flame retardant filling,polypropylene was used as carrier,and compounded two kinds of flame retardant masterbatch.By controlling the total mass fraction of the bromine-antimony flame retardant unchanged,adjusting the mass ratio of the bromine-based flame retardant and the antimony trioxide,using the vertical combustion method and the oxygen index method to test the effect of flame retardant masterbatch addition on flame retardancy of polypropylene.The impact of the addition of flame retardant masterbatch on the mechanical properties of polypropylene was tested using an impact tester and an electronic universal testing machine.The experimental results showed that the flame retardant masterbatch compounded with octabromoether as the main flame retardant had the best flame retardant effect on polypropylene.When the mass ratio of octabromoether to antimony trioxide was 3:1,the mass fraction of each substance was 27%of octabromoether,9%of antimony trioxide,34%of magnesium hydroxide and 30%of polypropylene,5%of the flame retardant masterbatch was added to the polypropylene,so that the modified polypropylene flame retardant level was increased from no grade to V-2,and the oxygen index was increased from 18 to 25.5.When the flame-retardant masterbatch was added 10%in polypropylene,the modified polypropylene had a flame retardant level of V-0,the oxygen index was increased to 28.5,and the impact strength of polypropylene was reduced by 0.4 kJ/m~2.The tensile strength was increased by 2 mPa,which had little effect on the mechanical properties of polypropylene.This indicated that the bromine-lanthanide flame retardant masterbatch prepared in this paper could greatly improve the flame retardancy of polypropylene and expanded the use of polypropylene in a flammable environment.