Tailored Hierarchical Bonding Networks Derive Ultra-Stable Underwater Adhesion in Harsh Environments

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• High-performance underwater adhesives are crucial for advancing underwater technologies.
• Achieving robust adhesion and long-term durability in harsh underwater environments presents significant challenges.

Purpose of the Study:

• To develop a novel hierarchical bonding network strategy for stable underwater adhesion.
• To engineer a polysiloxane backbone with synergistic multiscale interactions for enhanced adhesive properties.

Main Methods:

• Engineering a cross-linked polysiloxane backbone with hydroxyl groups, benzene rings, cations, and hydrophobic moieties.
• Creating synergistic multiscale interactions to amplify cohesion and interfacial adhesion.
• Testing adhesive strength, underwater adhesion, stability in corrosive environments, and thermal resilience.

Main Results:

• The optimized adhesive achieved a bonding strength of 12.2 MPa and underwater adhesion of 3.4 MPa on steel.
• The adhesive demonstrated stability in acidic, alkaline, and saline solutions over extended periods.
• Exceptional thermal resilience was observed across temperatures from -196 to 150 °C, alongside potent antibacterial and antifungal activity.

Conclusions:

• The hierarchical bonding network strategy enables stable adhesion under harsh underwater conditions.
• The developed adhesive offers strong adhesion, long-term durability, extreme temperature resistance, and antimicrobial properties.
• This work provides a new avenue for designing multifunctional adhesives for demanding underwater applications.