title: Enhanced wet adhesion and shear of elastomeric micro-fiber arrays with mushroom tip geometry and a photopolymerized p(DMA-co-MEA) tip coating.
abstract: Using principles inspired by the study of naturally occurring sticky systems such as the micro- and nanoscale fibers on the toes of geckos and the adhesive proteins secreted by marine animals such as mussels, this study describes the development and evaluation of a novel patterned and coated elastomeric microfibrillar material for enhanced repeatable adhesion and shear in wet environments. A multistep fabrication process consisting of optical lithography, micromolding, polymer synthesis, dipping, stamping, and photopolymerization is described to produce uniform arrays of polyurethane elastomeric microfibers with mushroom-shaped tips coated with a thin layer of lightly cross-linked p(DMA-co-MEA), an intrinsically adhesive synthetic polymer. Adhesion and shear force characterization of these arrays in contact with a glass hemisphere is demonstrated, and significant pull-off force, overall work of adhesion, and shear force enhancements in submerged aqueous environments are shown when compared to both unpatterned and uncoated samples, as well as previously evaluated patterned and coated arrays with differing geometry. Such materials may have potential value as repeatable adhesives for wet environments, such as for medical devices.
authors.affiliation: Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Glass
authors.forename: Hoyong
authors.initials: H
authors.lastname: Chung
authors.forename: Newell R
authors.initials: NR
authors.lastname: Washburn
authors.forename: Metin
authors.initials: M
authors.lastname: Sitti
mesh_terms: D000179:Acrylates / Q000737:chemistry*; D000269:Adhesives / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D004295:Dihydroxyphenylalanine / Q000737:chemistry; D004298:Dopamine / Q000031:analogs & derivatives* / Q000737:chemistry; D020724:Elastomers / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D055595:Mechanical Phenomena; D008689:Methacrylates / Q000737:chemistry; D055616:Microtechnology / Q000295:instrumentation*; D055668:Photochemical Processes; D058105:Polymerization / Q000528:radiation effects*; D011108:Polymers / Q000737:chemistry*
chemical_list: D000179:Acrylates; D000269:Adhesives; D020724:Elastomers; D008689:Methacrylates; D011108:Polymers; C556137:poly(dopamine methacrylate-co-2-methoxyetheyl acrylate); D004295:Dihydroxyphenylalanine; C004919:ethylene dimethacrylate; D004247:DNA; D004298:Dopamine