Switching water droplet adhesion using responsive polymer brushes

Langmuir. 2010 Jul 20;26(14):12377-82. doi: 10.1021/la101909e.

Abstract

Two stimuli-responsive polymers, poly(N-isopropylacrylamide) (PNIPAM) and poly(dimethylamino)ethyl methacrylate (PDMAEMA), were grafted from initiator-modified anodized alumina substrates with irregular micro/nanoscale surface topography. The resulting polymer-coated surfaces exhibited highly unusual wettability properties, as spherical water/acid/alkali/salt droplets could be reversibly switched between pinned states and rolling states due to the changes of temperature, pH, and electrolytes. The key to this effect is the combination of a mixed monolayer which provides initiator points for brush growth as well as a permanently hydrophobic substrate and a surface roughness.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acrylic Resins / chemistry*
  • Halogenation
  • Hydrogen-Ion Concentration
  • Hydrophobic and Hydrophilic Interactions
  • Methacrylates / chemistry*
  • Nylons / chemistry*
  • Surface Properties
  • Water / chemistry*

Substances

  • Acrylic Resins
  • Methacrylates
  • Nylons
  • poly(2-(dimethylamino)ethyl methacrylate)
  • Water
  • poly-N-isopropylacrylamide