A method of manufacturing a multi-layered propellant grain is provided. The method of the present disclosure simplifies the setup necessary to produce multi-layered propellants by using industrial equipment that is more energy and space efficient than the machinery that is conventionally employed for such processes. The method comprises providing a first propellant formulation; providing a die configured to provide a structure having an outer shell and a hollow interior when material is extruded therethrough; extruding the first propellant formulation through said die, to produce a first propellant layer having an outer shell defining a hollow interior in the form channel having open ends; providing a second propellant formulation, said second propellant formulation being of low viscosity; injecting said second propellant formulation into said channel defined by said first propellant layer to form a second propellant layer disposed in said channel; and hardening said second propellant layer. The first and second propellant layers have different rates of burning.

A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. This process may be performed over time to determine a lifespan of the propellant grain.

Propellant charges or grains having printed layers of two or more energetic materials are described along with methods for preparing and using them.

A solid rocket motor includes a first solid propellant and a second solid propellant at least partially surrounding the first solid propellant. The second solid propellant is resistant to fragment impact and the first solid propellant has a higher impulse than the second solid propellant.

A method of producing an energetic polymer comprises reacting at least one energetic diol with at least one of a diacid halide and a diacid halide derivative to produce a geminal dinitro polyester. A method of producing an energetic binder, and a method of producing an energetic composition are also described.

A method of forming polymer composites includes mixing a transition metal oxide precursor including at least one transition metal, a polymer as a binder, a solvent for the polymer, and water to form a first solution including polymer-transition metal complexes. The polymer-transition metal complexes are hydrolyzed to produce a plurality of transition metal oxide nanoparticles, wherein water is added in the mixing in a stoichiometric excess for the hydrolyzing. The solvent and residual of the water remaining after the hydrolyzing are removed. A polymer composite including the transition metal oxide nanoparticles dispersed in the polymer results after the removing, where some of the polymer is chemically conjugated to a surface of the transition metal oxide nanoparticles.

A method of forming polymer composites having transition metal oxide nanoparticles dispersed therein includes mixing a transition metal oxide precursor including at least one transition metal, a polymer as a binder, a solvent for the polymer, and water to form a first solution including polymer-transition metal complexes. The polymer-transition metal complexes are hydrolyzed to produce a plurality of transition metal oxide nanoparticles, wherein water is added in the mixing in a stoichiometric excess for the hydrolyzing. The solvent and residual of the water remaining after the hydrolyzing are removed. A polymer composite including a plurality of transition metal oxide nanoparticles dispersed in the polymer results after the removing, where some of the polymer is chemically conjugated to a surface of the transition metal oxide nanoparticles.

The invention is directed to a propellant charge, to a method of preparing a propellant charge, and to uses of the propellant charge. The propellant charge or grain of the invention comprises two or more energetic materials with different linear burn rate, wherein the two or more energetic materials are distributed within the charge or grain such that two perpendicular cross-sections of said propellant charge or grain have at least two linear burn rate gradients in non-parallel directions, wherein said propellant charge or grain is layered with layers having a layer thickness in the range of 1-10 000 m, wherein, if the propellant charge or grain has a longitudinal axis, at least one of said perpendicular cross-sections is along said longitudinal axis, and wherein said propellant charge or grain further comprises one or more perforations.

A method and compound includes mixing dichloroglyoxime with an alcohol containing an alkyne functional group in methanol to create a mixture; adding a salt compound and water to the mixture to create bis-isoxazole diol; and nitrating the bis-isoxazole diol to create 3,3-bis-isoxazole-5,5-bis-methylene dinitrate, which has the structural formula: ##STR00001##
The alcohol containing an alkyne functional group may include propargyl alcohol. The salt compound may include sodium bicarbonate. The method may include nitrating the bis-isoxazole diol with nitric acid. The nitric acid may include at least a concentration of 90% nitric acid in water. Alternatively, the method may include nitrating the bis-isoxazole diol with 100% nitric acid and acetic anhydride. The salt compound and the water may be added to the mixture over at least a six-hour period. The method may include mixing the mixture after adding the salt compound and the water for at least ten hours.

A method and compound includes mixing dichloroglyoxime with an alcohol containing an alkyne functional group in methanol to create a mixture; adding a salt compound and water to the mixture to create bis-isoxazole diol; and nitrating the bis-isoxazole diol to create 3,3-bis-isoxazole-5,5-bis-methylene dinitrate, which has the structural formula:

##STR00001##

The alcohol containing an alkyne functional group may include propargyl alcohol. The salt compound may include sodium bicarbonate. The method may include nitrating the bis-isoxazole diol with nitric acid. The nitric acid may include at least a concentration of 90% nitric acid in water. Alternatively, the method may include nitrating the bis-isoxazole diol with 100% nitric acid and acetic anhydride. The salt compound and the water may be added to the mixture over at least a six-hour period. The method may include mixing the mixture after adding the salt compound and the water for at least ten hours.