Fully recyclable multifunctional adhesive with high durability, transparency, flame retardancy, and harsh- environment resistance

Recyclable/reversible adhesives have attracted growing attention for sustainability and intelligence but suffer from low adhesion strength and poor durability in complex conditions. Here, we demonstrate an aromatic silox-ane adhesive that exploits stimuli-responsive reversible assembly driven by Tr -Tr stacking, allowing for elimina-tion and activation of interfacial interactions via infiltration-volatilization of ethanol. The robust cohesive energy from water-insensitive siloxane assembly enables durable strong adhesion (3.5 MPa shear strength on glasses) on diverse surfaces. Long-term adhesion performances are realized in underwater, salt, and acid/alkali solutions (pH 1-14) and at low/high temperatures (-10-90 degrees C). With reversible assembly/disassembly, the adhesive is closed-loop recycled (-100%) and reused over 100 times without adhesion loss. Furthermore, the adhesive has unique combinations of high transparency (-98% in the visible light region of 400-800 nm) and flame re-tardancy. The experiments and theoretical calculations reveal the corresponding mechanism at the molecular level. This Tr -Tr stacking-driven siloxane assembly strategy opens up an avenue for high-performance adhesives with circular life and multifunctional integration.

Automated summary

This study demonstrates a new type of aromatic siloxane adhesive that utilizes reversible assembly driven by Tr-Tr stacking, leading to strong adhesion and durability under complex conditions. The adhesive shows water resistance and efficient adhesion on diverse surfaces, and it can be recycled with high transparency and flame retardancy.