Development of a Polyuretbane Binder System Giving a 'Knottable' Composite Solid Propellant

Abstract

Polyurethane propellants, which constitute one of the 'work-horse' binder systems in modern solid rocketry are easily amenable for tailoring the mechanical properties in terms of variations in the molecular structure of the backbone polyols, the isocyanates and stoichiometry of the reactants. The paper deals with studies in developing an advanced binder system based on poly (oxy propylene glycol) and toluene-di-isocyanate, which is capable of accommodating high solids loading and conceding elongatlon at maximum stress, of more than 125 per cent. The gum-stock properties of the binder are related with those of a low molecular weight version and the results are explained based on the network theory of condensation polymers.