Bio-inspired adhesives triggered by polyelectrolyte complexation and composite surface priming

Abstract

Sandcastle worm cement protein inspired strong wet-contact adhesive was developed which enables both a triggered complexation of polyelectrolytes, and formation of a porous architecture. A catechol-functionalized weak poly-anion was premixed with a poly-cation in DMSO. When applied underwater to substrates, electrostatic complexation, phase inversion, and rapid setting were actuated by water-DMSO solvent exchange, which offers enhanced spatial and temporal control of complexation, fostering rapid and robust underwater adhesion. Marine mussel inspired catecholic primers were also developed which increases the adhesion strength of crosslinked PMA resin on mineral surfaces by up to an order of magnitude when compared with conventional primers such as silane- and phosphate- based grafts. Moreover, the strong and energy-dissipative interfacial bonding on to mineral surfaces provided significant reinforcement in ultimate strength and toughness of a highly rigid mineral-PMMA composite.