Abstract: Diethyl aluminum phosphate (DEAP), melamine phosphate (MP) and zinc borate (ZB) was used in polyamide11 (PA11), the limiting oxygen index, vertical burning UL 94 grade, and cone thermos value were characterized. The thermosstability was studied by thermal gravimetric analysis. The char constitution was analyzed by FTIR. The limiting oxygen index value of neat PA11 was only 23 % and without UL 94 rating. The sample containing 20 % DEAP possessed a limiting oxygen index value of 28 % with a V-2 grade in UL 94 test, and the sample containing 13 % DEAP/7 %MP and 12.5 % DEAP/7 %MP/0.5 %ZB gave rise to a limiting oxygen index of up to 29 % with V-1 rating in UL 94. The char was significantly expanded after the addition of 12.5 % DEAP/7 %MP/0.5%ZB.

Key words: polyamide11, diethyl aluminum phosphate, melamine phosphate, zinc borate, non-halogen flame retardant