Aging of HTPB-Based Solid Propellant Investigated by Dynamic Mechanical Analysis

Aging resulting in stabilization is one of the most important and advanced aspects of polymer chemistry. Solid propellants as polymer-based materials deal with aging process as well. This research work has evaluated Dynamic Mechanical Analysis (DMA) for characterization of composite propellant samples during an accelerated aging program. Although there are only a few reports in the open literature concerned with using DMA in aging studies they are not reported inside the country. In this method, the changes in storage module (É) and damping (tan) of the sample during the aging time versus temperature are investigated. Accelerated aging tests at 25, 45, 60, and 70°C were performed for the maximum 8000 h. Finally, we observed that damping efficiency decreases about 12% as a result of thermal aging. The resulted data may be used to determine the aging rate, service time and decomposition mechanism during the rocket storage.