Study Of Laboratory-Scale Burning Of Composite Solid Propellant For Novel Methods Of Nanoparticle Synthesis

Advancements in chemical synthesis techniques allow for the production of improved solid rocket propellant nano-scale additives. These additives show larger burning rate increases in composite propellants compared to previous additive generations. Previous methods involved the mixing of dry powders by way of grinding or applying an ultrasonic bath to pulverize the larger agglomerates in the powder additive. Dry titania nanoparticles were mixed into hydroxyl terminated polybutadiene (HTPB) and ammonium perchlorate (AP) composite solid propellants. Relative dispersion of the nano particles was indicated in the burning rate of the propellants synthesized, but with dry powders the burning rate enhancement was around 9% with the use of 0.5% by weight of the additive. In bimodal propellants, the use of a dry titania additive showed almost no improvement on the burning rate. In addition to improving additive effectiveness, novel synthesis methods helped improve manufacturability, reduced safety risks, and maximized energy efficiency of nano-scale burning rate enhancers. Burning rate increases as high as 69% from additive mass loadings of less than 0.5% were seen in non-aluminized, ammonium perchlorate-based propellants over the pressure spectrum of 500 psi (3.5 MPa) to 2250 psi (15.5 MPa). Increases in burning rate up to 73% were seen in similarly formulated aluminized propellants