Synergetic Effect of Magnesium Stannate on Intumescent Flame Retardanted Polypropylene

Into a flame retardant polypropylene composites containing poly(ethylene urea-formaldehyde) and ammonium polyphosphate,a small amount of magnesium stannat was introduced as a synergetic flame retarding agent.The flame retardant properties and the resultant char layers of the composites were studied through cone calorimeter,TG,FTIR,SEM,and EDX energy spectroscopy.The measured results showed that a loading of 1 wt% magnesium stannate increased combustion residue,improved the quality of char layers,and led to higher efficiency of flame retardancy,in addition,the burning time with flame was prolonged from 415 s to 805 s.Upon loaded with 1 wt% of magnesium stannate,for reaching a level of UL-94 V-0,the loading of flame retardant decreased from 32 % to 28 %,limited oxygen index rose from 33.4 % to 35.1 %,tensile strength of the composites increased from 24.3 MPa to 26.0 MPa,elongation at break increased from 23 % to 45 %,compared with devoid systems.