Advanced moisture-resistant Mg@PDA@PTFE: Proportional optimization and energy release characterization

The study focuses on resolving moisture-induced oxidative deactivation and Mg/PTFE interfacial bonding challenges in reactive materials by utilizing polydopamine (PDA) to bridge magnesium (Mg) and polytetrafluoroethylene (PTFE). Initially, a 5 % PDA content was set based on FIB-SEM and specific surface area results, yielding a surface area of 18.2794 m²/g for Mg@5%PDA. The contact angle reached 76.91°, a 19.62° increase over raw Mg, signifying improved hydrophobicity. Subsequently, analysis of the thermal and combustion behavior of Mg@PTFE indicated continuous improvement with increasing PTFE content, reaching an inflection point at 8 % PTFE. The DSC peak temperature of Mg@PTFE increased with higher PTFE content, indicating enhanced stability. However, the DSC heat release reaches its maximum of 5806 J/g at 8 % PTFE. Meanwhile, ignition delay minimized to 117 ms at 8 % PTFE, a 53.01 % reduction compared to 4 % PTFE. Additionally, the contact angle of Mg@8%PTFE was 96.12°, a 38.83° rise from raw Mg, further improving hydrophobicity. Finally, optimal PTFE content was determined to be 8 %. Hence, the Mg@5%PDA@8%PTFE dual-core shell structure was successfully fabricated, with hydrophobicity tests showing a contact angle of 108.54°, a significant 51.25°increase over raw Mg, demonstrating exceptional hydrophobicity.