Litchi-like Core-Shell HMX@HPW@PDA Microparticles for Polymer-Bonded Energetic Composites with Low Sensitivity and...

Area of Science:

• Materials Science
• Chemical Engineering
• Energetic Materials

Background:

• Paraffin wax introduction in energetic materials often reduces interfacial interaction and mechanical properties.
• Developing safer and mechanically robust energetic composites remains a significant challenge.

Purpose of the Study:

• To address the limitations of conventional paraffin wax in energetic materials.
• To design and fabricate novel core-shell energetic microcapsules with enhanced safety and mechanical performance.

Main Methods:

• Construction of a litchi-like core-shell structure: 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX)@high melting point paraffin wax (HPW)@polydopamine (PDA).
• Characterization of surface element states using X-ray photoelectron spectroscopy (XPS).
• Evaluation of impact energy using the Bundesanstalt für Materialprüfung (BAM) method.

Main Results:

• HMX@HPW@PDA particles showed a 117% increase in impact energy (from 6 J to 13 J) compared to HMX with low melting point paraffin wax.
• Energetic composites based on HMX@HPW@PDA exhibited superior mechanical properties, comparable to or exceeding raw HMX.
• The β-δ phase transition temperature of HMX was improved by 11.3 °C in HMX@HPW@PDA crystals.

Conclusions:

• The novel HMX@HPW@PDA core-shell structure effectively mitigates interfacial issues and enhances mechanical properties of energetic materials.
• This approach offers a scalable and creative method for fabricating high-safety energetic composites.
• The bioinspired PDA shell contributes to stronger interfacial interactions and improved material performance.