Rosin‐Derived Small‐Molecule Ionic Liquid Hot‐Melt Adhesives With Strong Adhesion Enabled by Noncovalent Interactions

ABSTRACT Designing small‐molecule adhesives that combine strong yet reversible adhesion remains challenging. Herein, a high‐performance rosin‐derived small‐molecule hot‐melt adhesive ADIm‐TFSI was developed by integrating hydrophobic rosin moieties with ionic groups and polar functionalities. The rigid hydrophobic fused‐ring structure of rosin not only endowed ADIm‐TFSI with high cohesive energy, but also effectively suppressed chain entanglement and increased the free volume, thereby facilitating interfacial interactions between the adhesive and substrates, promoting the formation of more interfacial hydrogen bonds (H‐bonds), and ultimately enhancing adhesion performance. Meanwhile, the ionic and polar groups improve interfacial adhesion by noncovalent interactions (e.g., H‐bonding and electrostatic interactions). Benefiting from these synergistic noncovalent interactions, ADIm‐TFSI exhibited strong and durable adhesion on various substrates, with a maximum adhesion strength of 13.77 MPa at room temperature. In addition, dynamic H‐bonds enabled thermally triggered debonding and reversible adhesion with negligible fatigue‐related degradation after 10 cycles. ADIm‐TFSI also exhibited several desirable properties, including solvent and humidity resistance, recyclability, and antimicrobial activity. This work presents a rational strategy for designing high‐performance multifunctional small‐molecule adhesives for diverse application scenarios.