Enhanced adhesion of bioinspired nanopatterned elastomers via colloidal surface assembly.
We describe a scalable method to fabricate nanopatterned bioinspired dry adhesives using colloidal lithography. Close-packed monolayers of polystyrene particles were formed at the air/water interface, on which polydimethylsiloxane (PDMS) was applied. The order of the colloidal monolayer and the immersion depth of the particles were tuned by altering the pH and ionic strength of the water. Initially, PDMS completely wetted the air/water interface outside the monolayer, thereby compressing the monolayer as in a Langmuir trough; further application of PDMS subsequently covered the colloidal monolayers. PDMS curing and particle extraction resulted in elastomers patterned with nanodimples. Adhesion and friction of these nanopatterned surfaces with varying dimple depth were studied using a spherical probe as a counter-surface. Compared with smooth surfaces, adhesion of nanopatterned surfaces was enhanced, which is attributed to an energy-dissipating mechanism during pull-off. All nanopatterned surfaces showed a significant decrease in friction compared with smooth surfaces.
Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
Sabine
S
Akerboom
Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
Jeroen
J
Appel
Insect Biomechanics Workgroup, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
David
D
Labonte
Insect Biomechanics Workgroup, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
Walter
W
Federle
Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
Joris
J
Sprakel
Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands marleen.kamperman@wur.nl.
Marleen
M
Kamperman
D000388:Air; D055592:Biophysical Phenomena; D003102:Colloids / Q000737:chemistry*; D003460:Crystallization; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D017276:Friction; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008027:Light; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry; D012542:Scattering, Radiation; D013499:Surface Properties; D014867:Water / Q000737:chemistry
D003102:Colloids; D004129:Dimethylpolysiloxanes; D007477:Ions; D011137:Polystyrenes; D014867:Water; C013830:baysilon
adhesion; bioinspiration; colloidal lithography; nanopatterned surfaces; self-assembly