Modification of Combustion Performance and Mechanical Properties of HTPB-Based High-Energy Composites with Non- Reactive Polyhedral Oligomeric Silsesquioxane Nanostructures

Abstract This research effort was aimed at elucidating the effect of Octa-isobutyl-silsesquioxane (OIBS) and Octa-phenyl-silsesquioxane (OPS) nanostructures on the mechanical and Combustion Performance of Hydroxyl-terminated polybutadiene (HTPB) High-energy composites (HECs). This research included the investigation of mechanical properties in different concentrations of 0.1, 0.5, 1.5, and 2.5 wt% of Polyhedral Oligomeric Silsesquioxane (POSS). It should be noted that in the concentration of 0.1 wt% of POSS, elongation was observed along with a decrease in the mechanical strength of the composite On the contrary, with increasing concentration from 0.1 to 2.5 wt%, an increase in mechanical strength occurred. These findings were more pronounced for OPS than OBS. In addition, the combustion performance of HEC mixed with 0.5 wt% POSS was evaluated. Then the original samples, these nanostructures showed an increase in the burning rate of the sample. Significantly, the burning rate of HECs containing OIBS exceeded that of OPS. Findings obtained through XRD (X-ray Diffraction) and SEM (Scanning Electron Microscopy) analysis proved that POSS nanostructures increase the performance and combustion efficiency of HECs. In conclusion, a mechanism was proposed to improve the mechanical and combustion properties of HECs by POSS nanostructures distributed in the composite matrix.