THE DEVELOPMENT AND EVALUATION OF A HYDROCARBON BINDER FOR HIGH ENERGY SOLID PROPELLANTS.

Abstract : The acquisition and characterization of hydroxy terminated Telagen S was continued. The functionalities by molecular weight to equivalent weight ratio continue to be below 1.7, but cured binders indicated functionalities in excess of 1.85. The equivalent weights determined by reaction with n-butyl isocyanate were within 2% of values obtained by the manufacturer of the prepolymers. Thin-layer chromatography was used to demonstrate the presence of nonfunctional and monofunctional fractions in Telagen S. Considerable effort was devoted to improving the low temperature properties which may be caused by the high concentration of polar groups in the saturated binder. The use of substitutes for CTI and catalysts studies to achieve room temperature cures were also pursued. PAPI gave good cures with Telagen S, but 1,2,6-hexanetriol has been eliminated as a substitute for CTI. The processing of Telagen S propellants at room temperature is apparently limited more by prepolymer viscosity than by cure rate. Burning rate studies indicate very similar rates for saturated and unsaturated polybutadiene propellants. Cyclic imides have been eliminated as a cure system for advanced oxidizers because of very slow reaction rate with hydroxy groups. The more rapid reacting acid anhydrides have more potential in this area. After two months of aging at 170 F and at relative humidities in excess of 25%, both Telagen S and Minuteman Wing VI Second Stage propellants are degraded.