Developing mechanically robust, self-healable, and antibacterial poly(dimethylsiloxane) elastomers through the introduction of metal-polyphenol networks

Abstract

The development of mechanically robust and self-healable poly(dimethylsiloxane) (PDMS) elastomers for medical applications remains a significant challenge due to their inherent mechanical limitations. In this work, we engineered a series of PDMS-based elastomers by strategically integrating metal-phenolic networks (MPNs) into PDMS-based polyurea matrices, achieving synergistic enhancements in mechanical performance, self-healing capability, and antibacterial functionality. The MPN architecture, characterized by an abundance of dynamic supramolecular interactions, including hydrogen bonding and metal–ligand coordination, enabled substantial mechanical reinforcement, yielding composite PDMS-based polyurea elastomers with tensile strength of ∼7.7 MPa, elongation at break of ∼823.4%, and exceptional toughness of ∼39.2 MJ m⁻³. These values represent a ∼133% increase in tensile strength and a ∼119% improvement in toughness compared to baseline PDMS elastomers. The intrinsic reversibility of these supramolecular motifs further endowed the elastomers with remarkable self-healing performance, achieving ∼97.2% recovery of initial mechanical integrity after 6 h of thermal treatment at 75 °C. Importantly, leveraging the bioactive properties of plant-derived polyphenol components within the MPNs, these PDMS elastomers demonstrated potent antibacterial activity against clinically prevalent pathogens (S. aureus and E. coli), exhibiting over ∼98% bacterial inhibition efficiency, which is a critical feature for reducing biofilm formation in medical device applications. This multifunctional design paradigm not only resolves the historical trade-off between mechanical strength and self-healing capacity in PDMS elastomers but also introduces inherent antimicrobial protection, which paves an avenue for developing durable, infection-resistant medical devices that align with the growing demand for sustainable healthcare technologies.