Influence of Cellulosic Binders on Sensitivity and Combustion Behaviour of B-KNO3 Ignition System

Boron-potassium nitrate (B-KNO3)-based compositions have been used as an effective ignitersystem for solid rocket propellants. A systematic study was undertaken to generate exhaustivedata on B-KNO3 (25:65)-based ignition systems with cellulosic binders, viz., nitrocellulose, ethylcellulose and plasticised ethyl cellulose. In addition, detailed investigations were carried outwith PEC as binder by varying its concentration from 2-10 per cent in the same system. Theexperimental compositions (B-KNO3: binder) were evaluated by closed-vessel firing, thermalanalysis, sensitivity, mechanical properties and cal-val determination. The binders significantlyinfluenced the sensitivity and combustion behaviour of B-KNO3 compositions. The compositionwith nitrocellulose as binder produced high flame temperature and cal-val as compared to ethylcellulose and plasticised ethyl cellulose-based compositions. The data indicated that thecalculated flame temperature for all compositions was in the range 2716 K to 2957 K. As theplasticised ethyl cellulose content increased from 2 per cent to 10 per cent, the maximum pressureincreased with decrease in heat of combustion