Engineering of Low Shrinkage Foams Stabilized by Metal–Phenolic Networks for Wound Healing

Lightweight porous materials hold immense potential across industrial and biomedical applications, while conventional fabrication methods face challenges including energy-intensive drying processes, structural collapse, and limited mechanical strength. Herein, we report a universal strategy to engineer robust dry foams stabilized by metal-phenolic networks (MPNs) through a synergistic combination of high-speed mechanical foaming and freeze-thaw drying process. By introducing carboxymethyl chitosan (CMCS) and metal ions for rapid cross-linking, the foam templates can be stabilized to overcome the instability of conventional foams, enhancing solvent exchange efficiency and achieving hierarchical porosity. The integration of metal-phenolic coordination during the freeze-thaw process further reinforces the CMCS skeletal framework, yielding materials with exceptional mechanical integrity (<16% shrinkage and >80 kPa Young's modulus) and ambient-drying compatibility. The resultant MPN-stabilized dry foams (MPN foams) exhibit excellent antibacterial activity and angiogenesis promotion for wound healing applications.