Developing High-strength Supramolecular Adhesives with Controlled Liquid Inclusion: from Mechanistic Study to Antibacterial Applications

Adhesives that can bind to diverse synthetic and biological surfaces in wet environments have great technical implications in areas ranging from aquatic vehicles and underwater soft robotics, to tissue engineering, wound dressing and biomedical devices. Currentdesign strategies are mainly focused on hydrogels or hydrogel-derived adhesives. However, there are intrinsic limitations for the hydrogel-based adhesives, such as the lack of mechanical strength, insufficient interfacial toughness/adhesion, and the incompatibility with water-insoluble drugs. To address these challenges, developing organogel-based supramolecular adhesives with high mechanical stability and controlled inclusion of bioactive oils could be an alternative approach.The PI’s group recently made a couple of achievements on the chemistry synthesis and molecular engineering of supramolecular polymer, gels and adhesives. We demonstrated hydrogen-bond crosslinked supramolecular polymers in coating and adhesiveapplications. Particularly, comparing to traditional supramolecular organogel, our results revealed that multiphase assembly of siloxane oligomers may help better engineer materials mechanics and interfacial bonding with a certain amount of oil inclusion. In this project, we propose to synthesize a variety of oligomers that can be crosslinked through hierarchical hydrogen bonds and assemble into continuous networks. We expect that biogenic antimicrobial oils may serve as organic solvent in the preparation oforganogel-based supramolecular adhesives, and be incorporated into the gel matrix afterwards. The encapsulated oils could further serve as a structural/functional component in controlling the interfacial and mechanical properties of supramolecular adhesives. The associated mechanistic study will not only help us elucidate the molecular mechanism on performance regulation of supramolecular adhesives with a wide range of oil inclusion, but also guide us on the implementation of the developed antimicrobial adhesives to fulfill specific requirements in practical applications. The outcome of this project will advance our fundamental understanding on the molecular engineering of organogel-based supramolecular adhesives, and provide new insights into the design of supramolecular materials which will benefit their potential applications in soft robotics, flexible electronics, and biomedical applications.