Mechanoresponsive Tuning of Anisotropic Wetting on Hierarchically Structured Patterns

Abstract

Here, we propose a simple mechanoresponsive system on patterned soft surfaces to manipulate both anisotropy and orientation of liquid wetting. On the poly(dimethylsiloxane) embedding line patterned structures, additional topographies, such as wrinkles and cracks, can be provided by applying compressive and tensile stress, respectively. This tunable hierarchy of structures with the different scales and directions of lines, wrinkles, and cracks allow the mechanoresponsive control of anisotropic wetting in a single platform. In addition, the wetting behavior on those surfaces is precisely investigated based on the concept of critical contact angle to overcome the ridges in a step flow.

Droplet motion on a wrinkled PDMS surface with a gradient structural length scale shorter than the droplet diameter

“…A typical preparation procedure is (1) creating a thin hard layer on the so material under a pre-strain condition, and (2) releasing the applied strain. [17][18][19][20][21][22][23][24][25][26][27] In recent years, investigations have used polydimethylsiloxane (PDMS) as a so elastic substrate. The material of the thin hard layer depends on the preparation procedure.…”

“…The material of the thin hard layer depends on the preparation procedure. In particular, a silicate layer was formed through oxygen plasma irradiation 17,18 or ultraviolet-ozone treatment, 19,20 and several metals were applied through deposition. [21][22][23] A characteristic dimension of a wrinkle is its wavelength, which ranges from the order of hundreds of nanometers to tens of micrometers, and is related to mechanical properties of the bilayer system and thickness of the thin layer.…”

Large‐Range, Reversible Directional Spreading of Droplet on a Double‐Gradient Wrinkled Surface Adjusted Under Mechanical Strain

“…[ 79 ] Inspired by this, Kwon et al proposed a simply responsive mechanical system on patterned soft surfaces to manipulate both the anisotropy and orientation of liquid wetting. [ 80 ] However, they did not study the spreading length of the droplets on this soft material system and corresponding control method.…”

Fundamentals and utilization of solid/ liquid phase boundary interactions on functional surfaces

“…Another promising way of wettability regulation is the utilization of mechanical stimuli to alter surface texture [183]. In most of the literature examples of this feature, elastomeric matrix materials, such as PDMS [184,185] are applied to promote reversible transitions.…”