Solid-fuel rocket propellants comprising an oxidizer, an oxophilic metal-halophilic metal formulation, and a binder are described herein. Further described are processes for preparing such propellants and methods of reducing hydrogen chloride production via the combustion of such propellants. Non-limiting examples of such formulations include aluminum-lithium alloys.

A hybrid rocket solid fuel grain having a cylindrical shape and defining a center port is additive manufactured from a compound of thermoplastic fuel and passivated nanocomposite aluminum additive. The fuel grain comprises a stack of fused layers, each formed as a plurality of fused abutting concentric circular beaded structures of different radii arrayed defining a center port. During operation, an oxidizer is introduced along the center port, with combustion occurring along the exposed port wall. Each circular beaded structure possesses geometry that increases the surface area available for combustion. As each layer ablates the next abutting layer, exhibiting a similar geometry is revealed, undergoes a gas phase change, and ablates. This process repeats and persists until oxidizer flow is terminated or the fuel grain material is exhausted. To safety achieve this construction, a fused deposition additive manufacturing apparatus, modified to shield the nanocomposite material from the atmosphere is used.

Optically sensitized binders which are energetic polyphosphazenes tailored at the molecular level to achieve enhanced absorption of electromagnetic radiation by having attached thereto a chromophore to absorb light and therefore ignite the binder in use.

A hybrid rocket solid fuel grain having a cylindrical shape and defining a center port is additive manufactured from a compound of thermoplastic fuel and passivated nanocomposite aluminum additive. The fuel grain comprises a stack of fused layers, each formed as a plurality of fused abutting concentric circular beaded structures of different radii arrayed defining a center port. During operation, an oxidizer is introduced along the center port, with combustion occurring along the exposed port wall. Each circular beaded structure possesses geometry that increases the surface area available for combustion. As each layer ablates the next abutting layer, exhibiting a similar geometry is revealed, undergoes a gas phase change, and ablates. This process repeats and persists until oxidizer flow is terminated or the fuel grain material is exhausted. To safety achieve this construction, a fused deposition additive manufacturing apparatus, modified to shield the nanocomposite material from the atmosphere is used.

Substituted poly(phosphazene) compounds comprising a combination of units having one or more of the structures (i) to (iii) wherein: the combination comprises R.sub.1 and R.sub.2; each R.sub.1, is independently an optionally substituted alkyl- or alkyl ether-based side chain containing an isocyanate-reactive moiety, an epoxide-reactive moiety, an amine-reactive moiety, a supramolecular noncovalent bonding moiety, or combinations thereof; and each R.sub.2 is independently an optionally substituted alkyl- or alkyl ether-based side chain containing nitro, nitramine, nitrate ester, azide, an ammonium compound moiety with energetic counter-ion, or combinations thereof. Methods of making the compounds are also described.

The present disclosure relates to a solid propellant composition for curing azide-alkyne triazole, which cures a propellant by forming a polymer network using triazole groups formed by a reaction between an azide compound and an alkyne compound, and a method for preparing a solid propellant using same.