Enhancing shock wave energy dissipation in metallosupramolecular polymer by tuning metal-imidazole coordination interactions

Abstract

The development of materials capable of shock wave energy dissipation (SWED) is critical for modern protective applications. In this study, metallosupramolecular poly(dimethylsiloxane) (PDMS) networks cross-linked with Zn2+, Cu2+, and Ni2+ ions and imidazole ligands were designed to enhance SWED by leveraging the dynamic nature of metal-ligand coordination bonds. A laser-induced shock wave technique revealed that Cu2+ cross-linked PDMS exhibited superior SWED performance, likely due to coordination rearrangement dynamics occurring within a relevant timescale for shock wave dissipation. Time-temperature superposition (TTS) analysis indicated that while associative ligand exchange may assist in shock attenuation, metal-ligand bond dissociation plays a more dominant role under extreme shock conditions. DFT calculations further demonstrated that coordination geometry significantly influences SWED performance, with Cu2+ in square planar (trans) coordination exhibiting greater rupture susceptibility. These findings highlight the tunability of metal-ligand interactions as an effective strategy for optimizing energy dissipation in metallosupramolecular polymers. Additionally, they provide a comprehensive SWED mechanism analysis by synergistically integrating a laser-induced shock wave test and DFT calculations.