This study investigates the dynamic mechanical properties and molecular relaxation mechanisms of glycidyl azide polymer-based energetic thermoplastic elastomer (GAP-ETPE) through dynamic mechanical analysis (DMA). This work quantitatively revealed the constitutive relationship between the molecular motion pattern and the macroscopic performance of GAP-ETPE. Frequency-dependent DMA tests demonstrated that increased loading frequency shifts storage modulus ( E ') curves toward higher temperatures, with glass transition temperature ( T g , defined by E '' peak) ranging from −36.25 °C to −32.71 °C. Exponentially Modified Gaussian (EMG) deconvolution identified three molecular motional units: Peak 1 (soft-segment relaxation), Peak 2 (imperfect hard-segment domains), and Peak 3 (ordered hard-segment microcrystals). Frequency increases drove a 20.6% reduction in Peak1 contribution while elevating Peak2 and Peak3 by 16.79% and 3.75%, respectively, indicating hard-segment reorganization under dynamic loads. A master curve for E ' was established via time-temperature superposition (TTS), enabling prediction of viscoelastic behavior across extended frequencies (10 −3 –10 3 Hz) with an Arrhenius-derived activation energy of 291.11 kJ·mol -1 . This work provides important insights into the dynamic mechanical properties of GAP-ETPE under complex use conditions, supporting the design of adhesives for high-energy composites. This study systematically investigates the viscoelastic behavior of GAP-ETPE propellants using advanced dynamic mechanical analysis techniques. By employing EMG deconvolution to resolve complex relaxation processes and constructing master curves based on the time-temperature superposition principle, the research elucidates the viscoelastic evolution of the material under varying conditions. • This work Firstly quantitatively revealed the constitutive relationship between the molecular motion pattern and the macroscopic performance of GAP-ETPE by EMG method • A systematic study was conducted on the dynamic mechanical properties of GAP-ETPE across a broad frequency range (1–20 Hz) and a wide temperature range (-60 to 80°C), The glass transition temperature is as low as -36.25°C investigating its dynamic mechanical behavior under complex loading conditions. • master curve of the storage modulus was established, and realized the performance prediction of the ultra-wide time scale of 10 8.27 s Ultra-wide time scale (>6 years) performance prediction, which fills the experimental data gap under extreme working conditions
Liu et al. (Thu,) studied this question.