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AssigneeThe United States of America as represented by the Secretary of the Navy
InventorDonald E. Elrick
Estimating the term…
A typical rocket motor includes a motor casing containing a cast propellant onded to the casing and provided with a port through which combustion gases are delivered to the motor nozzle. During storage and operation, mechanical stresses in the propellant may produce tears resulting in motor malfunctions. Tear strength can be increased by reactively forming on selected port surface areas a thin-film cross-linked polymeric gel coating formed essentially of a highly functional polyglycol adipate and a polyfunctional isocyanate. Cross-linking with the propellant can be achieved by controlling the hydroxyl to isocyanate ratios of the coating and the propellant. The coating is particularly useful on XLDB (cross-linked, composite-modified double base) and on CMDB (composite-modified double-base) propellants.
A method of increasing the tear strength of the propellant of a rocket motor in which the propellant is a molded structure formed with an axial gas-conducting port, said method including the steps of:
A polymeric coating for use on the port surfaces of a rocket motor propellant having an axially-extending gas-conducting port, said propellant including an oxidizer material and a binder formed of a plasticizer and a polymer system, the latter being formed by a reaction product of polyglycol adipate and a diisocyanate, said coating comprising:
A rocket motor comprising:
Dependencies are inferred from the claim text.