Properties of high-energy propellants based on oxygen-enriched thermoplastic elastomer binders

Composite propellants are widely used in applications ranging from gas generators and small rockets to large rocket systems in space programs. This study presents a novel thermoplastic elastomer (TPE) binder system based on oxygen-enriched polyether-block-amide (PEBA) copolymer, designed to enhance the performance of composite propellants while reducing waste and environmental impact. Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) were used to characterize the TPE binder, revealing favorable thermal and structural properties. The burning rate of propellants incorporating this binder was evaluated using ammonium perchlorate (AP) oxidizer of varying particle sizes and aluminum (Al), with and without the addition of lithium fluoride as a burning-rate modifier. Results demonstrate that the oxidizer particle size significantly affects the burning rate, and lithium fluoride effectively reduces it, depending on its concentration in the propellant formulation. Compared to traditional hydroxyl‑terminated polybutadiene (HTPB)-based systems, propellants formulated with the PEBA-based binder exhibit improved energy performance, comparable burning rates, and advantageous processing and aging characteristics, all at a reduced cost.