title: Underwater contact adhesion and microarchitecture in polyelectrolyte complexes actuated by solvent exchange.
abstract: Polyelectrolyte complexation is critical to the formation and properties of many biological and polymeric materials, and is typically initiated by aqueous mixing followed by fluid-fluid phase separation, such as coacervation. Yet little to nothing is known about how coacervates evolve into intricate solid microarchitectures. Inspired by the chemical features of the cement proteins of the sandcastle worm, here we report a versatile and strong wet-contact microporous adhesive resulting from polyelectrolyte complexation triggered by solvent exchange. After premixing a catechol-functionalized weak polyanion with a polycation in dimethyl sulphoxide (DMSO), the solution was applied underwater to various substrates whereupon electrostatic complexation, phase inversion, and rapid setting were simultaneously actuated by water-DMSO solvent exchange. Spatial and temporal coordination of complexation, inversion and setting fostered rapid (∼25 s) and robust underwater contact adhesion (Wad ≥ 2 J m(-2)) of complexed catecholic polyelectrolytes to all tested surfaces including plastics, glasses, metals and biological materials.
authors.affiliation: Materials Research Laboratory, University of California, Santa Barbara, California 93106, USA.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
authors.forename: Dong Woog
authors.initials: DW
authors.lastname: Lee
authors.affiliation: Marine Science Institute, University of California, Santa Barbara, California 93106, USA.
authors.forename: B Kollbe
authors.initials: BK
authors.lastname: Ahn
authors.affiliation: Marine Science Institute, University of California, Santa Barbara, California 93106, USA.
authors.forename: Sungbaek
authors.initials: S
authors.lastname: Seo
authors.affiliation: Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
authors.forename: Yair
authors.initials: Y
authors.lastname: Kaufman
authors.affiliation: Materials Research Laboratory, University of California, Santa Barbara, California 93106, USA.|Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
authors.forename: Jacob N
authors.initials: JN
authors.lastname: Israelachvili
authors.affiliation: Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, California 93106, USA.
authors.forename: J Herbert
authors.initials: JH
authors.lastname: Waite
mesh_terms: D000269:Adhesives / Q000737:chemistry*; D000818:Animals; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry / Q000378:metabolism; D011077:Polychaeta / Q000737:chemistry* / Q000378:metabolism; D000071228:Polyelectrolytes; D011108:Polymers / Q000737:chemistry / Q000378:metabolism; D014867:Water / Q000737:chemistry*
chemical_list: D000269:Adhesives; D004121:Dimethyl Sulfoxide; D011073:Polyamines; D000071228:Polyelectrolytes; D011108:Polymers; D014867:Water