Study On The Preparation And Application Of Mg-Al Composite Flame Retardant

Magnesium aluminum composite flame retardant with different Mg-Al radio were prepared by co-precipitation method firstly,the samples were characterized through XRD,BET,bulk density TEM,and TG-DTA,the best Mg-Al ratio was screened out.On the basis of this work,the orthogonal optimization was used to determine the best process of this experiment;then,SDS,MAP,SDS/MAP were used as surface modifier at the same synthetic process,and the modified product were applied in polypropylene plastic,the combustion performance and mechanical properties of the composite system were studied.Magnesium aluminum composite flame retardant were prepared by chemical co-precipitation method,when the Mg/Al molar ratio was 4:1,the sample showed flake curly morphology,good dispersion,and light reunite,the thermal decomposition temperature reaches 350?.The sample were mainly the mixture of Mg(OH)2 and the Mg6Al2(OH)18·4.5H2O.The optimal synthesis conditions were screened out by the range analysis and variance analysis,that were the temperature 85?,reaction time 1h,Mg2+ concentration of the starting 1.5mol/L.The SDS was used as surface modifier,the performance and application of particles before and after modification were studied,the results showed that:the modified Mg-Al composite flame retardant showed improved dispersion,reduced degree of agglomeration,relatively increased thermal stability;and its application in polypropylene plastic effect:after modification,when the flame retardant in PP dosage of 40%the data can be achieved such as the limiting oxygen index of 27.0,smoke suppression effect is obvious,notched impact strength of 38J/m,strong tensile strength 26.44MPa,and elongation at break of 6.98%.The Mg-Al composite flame retardant modified by MAP showed good dispersion,light reunion,and relatively high thermal stability.The application results in PP:when the flame retardant in PP dosage of 40%the data can be achieved such as the limiting oxygen index of 29.2,smoke suppression effect is obvious,notched impact strength of 37J/m,strong tensile strength 22.34MPa,and elongation at break of 8.95%.The application results of powders modified by SDS/MAP in PP:when the flame retardant in PP dosage of 40%the data can be achieved such as the limiting oxygen index of 29.5,smoke suppression effect is obvious,notched impact strength of 39J/m,strong tensile strength 25.34MPa,and elongation at break of 9.95%.The application results of the three modified particles in pp showed that the flame retardancy was achieved when the filler content of 40%.Among them,the highest oxygen index was obtained when the sample were modified by SDS/MAP,while there is little difference between them in the aspects of affecting mechanical properties.In terms of the minimal effect to tensile properties of the material and the lower usage,the compound modifier can be used economically.