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Stress Relaxation Behavior of Azido Propellant Based on BAMO-THF at High Temperatures
Yiwen Hu1, Xiuduo Song1, Weilu Yang1
1Xi'an Modern Chemistry Research Institute, Xi'an 710065, China.
Materials (Basel, Switzerland)
|January 11, 2025
Summary
Azido propellants offer high energy but face heat resistance challenges. Improving microstructure ordering enhances their heat resistance and mechanical performance for broader applications.
Area of Science:
- Propellant Chemistry
- Materials Science
- Polymer Engineering
Background:
- Azido propellants are high-energy, low-signature materials.
- Limited heat resistance and mechanical performance restrict their use.
- 3,3-bis(azidomethyl) oxetane-tetrahydrofuran copolyether (BAMO-THF) is a key component.
Purpose of the Study:
- To prepare and characterize novel azido propellants based on BAMO-THF.
- To investigate the structure-properties relationship of these propellants.
- To enhance the heat resistance and mechanical performance of azido propellants.
Main Methods:
- Preparation of four BAMO-THF based azido propellants.
- Characterization of physical, energetic, and microstructural properties.
- Investigation of tensile and dynamic mechanical performances.
Main Results:
- Propellants exhibit elastomeric composite behavior with significant relaxation.
- Formula structure strongly influences relaxation behavior, distinct from testing conditions.
- Replacing diamine with diol as a chain extender improves low-temperature toughness but increases high-temperature stress relaxation.
Conclusions:
- Improving microstructure ordering and network integrity effectively restricts stress relaxation.
- This approach enhances heat resistance and high-temperature mechanical performance.
- Developed azido propellants show potential for high-energy formulations with improved stability.
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