Combustion Properties of Some High Solid Loading Butalites Compositions

The combustion(ballistic) properties of a high solid loading composite solid propellant family(Butalites) was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre-polymer(HTPB) as a fuel binder main backbone,bimodal system ammonium perchlorate oxidizer(AP) and aluminum powder(Al) as metallic fuel.Burning rates were doubled at various pressures,when solids loading(AP and 17% Al) were increased from 80 to 88% and the measured characteristic velocity values were increased by about 100 m/sec.The pressure exponent(n) values were lower with 80-85% solids loading.The burning rates were increased by about 2-5% when comparing the data obtained by static firing with those obtained by the strand burner method.