Synthesis, Characterization and Binding Properties of Epoxy Resins Based on Carbonohydrazones and Thiocarbonohydrazones

Abstract

Solid fuels capable of igniting spontaneously on coming into contact with liquid oxidizers have been used widely in hybrid propellant motors. Although the hybrid systems combine many advantages of both the solid and the biliquid rocket motors, for smooth operation of the motor the ignition delay, i.e. the elapsed time preceding ignition after the liquid oxidizer comes in contact with the solid fuel, must be very short. In our earlier studies 1,2 several hypergolic solid fuel powders igniting with oxidizers, such as white fuming nitric acid with very short ignition delay (WFNA) were developed. In actual use, however, the powder fuels have to be cast in a ‘grain’ form using polymeric binders. Casting of a highly hypergolic fuel powders using conventional binders like carboxyl or hydroxyl terminated polybutadiene (CTPB or HTPB) although results in imparting good mechanical strength to the fuel grain, the ignition delay becomes intolerably long. The present study was undertaken to develop new high energy resins which could be used as binders for hypergolic fuel powders without affecting their ignition delay significantly, and also providing good mechanical strength to the grain.