title: Design and fabrication of zwitter-wettable nanostructured films.
abstract: Manipulating surface properties using chemistry and roughness has led to the development of advanced multifunctional surfaces. Here, in a nanostructured polymer film consisting of a hydrophilic reservoir of chitosan/carboxymethyl cellulose capped with various hydrophobic layers, we demonstrate the role of a third design factor, water permeation rate. We use this additional design criterion to produce antifogging coatings that readily absorb water vapor while simultaneously exhibiting hydrophobic character to liquid water. These zwitter-wettable films, produced via aqueous layer-by-layer assembly, consist of a nanoscale thin hydrophobic capping layer (chitosan/Nafion) that enables water vapor to diffuse rapidly into the underlying hydrophilic reservoir rather than nucleating drops of liquid water on the surface. We characterize these novel films using a quartz crystal microbalance with dissipation monitoring (QCM-D) and via depth-profiling X-ray photoelectron spectroscopy (XPS) in addition to extensive testing for fogging/antifogging performance.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Hyomin
authors.initials: H
authors.lastname: Lee
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Gilbert
authors.forename: Francesco E
authors.initials: FE
authors.lastname: Angilè
authors.forename: Rong
authors.initials: R
authors.lastname: Yang
authors.forename: Daeyeon
authors.initials: D
authors.lastname: Lee
authors.forename: Michael F
authors.initials: MF
authors.lastname: Rubner
authors.forename: Robert E
authors.initials: RE
authors.lastname: Cohen
keywords: antifogging coatings; condensation; layer-by-layer; surface science; wetting; zwitter-wettability