Rapid Underwater Adhesion via Photo-Activated Chemically Cross-Linked Hybrid Network

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• Underwater adhesives are crucial for marine applications but face challenges like solvent toxicity and poor adhesion.
• Existing technologies struggle with irregular surfaces and dynamic aquatic conditions.

Purpose of the Study:

• To develop a high-performance, fast-curing underwater adhesive.
• To overcome limitations of current solvent-based or condition-dependent adhesives.

Main Methods:

• Phototriggered copolymerization of acrylate-functionalized polyurethane (PU) prepolymers and acrylic acid (AA).
• Formation of a single, covalently hybrid network combining PU and poly(acrylic acid) (PAA) domains.
• Utilizing AA as a reactive monomer and plasticizer for improved wettability and adhesion.

Main Results:

• The hybrid adhesive demonstrated good wettability and initial adhesion on curved/rough surfaces.
• Rapid UV-curing achieved lap-shear strength of ~1.2 MPa in 5s and ~2.5 MPa in 20s on glass.
• The adhesive exhibited resistance to underwater turbulence.

Conclusions:

• A novel chemically hybrid adhesive network was successfully synthesized.
• This adhesive offers a promising solution for rapid underwater repair and sealing.
• The formulation enables robust bonding in dynamic aquatic environments without toxic solvents.