Characteristics of Insulators or Insulating Materials

The insulating material or insulator must possess a number of properties [358] and the most important are  

1) Chemical compatibility with the components of the motor, that is, it should not upset the chemistry of propellant and other components of the motor. 

2) Excellent bond with motor, liner and propellant over a wide range of temperatures, that is, -40 °C to +60 °C. It should also be sustainable in this temperature range throughout the Service life of insulated motors. 

4) Low ablation rate and low density in order to minimize the inert mass on board. Also, the resulting char must remain porous and the resulting gases must be of low molecular mass. At the same time, pyrolysis of the insulating material must not lead to emission of smoke or flashes. 

7) Good ageing characteristics so that the case-bonded motor has a minimum 10-12 years of Service life. 

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