BROWSE

Related Researcher

Author's Photo

Jeong, Hoon Eui
Multiscale Biomimetics & Manufacturing Lab
Research Interests
  • Biomimetics
  • Multiscale manufacturing
  • Micro/nanofabrication

ITEM VIEW & DOWNLOAD

Wetting transition and optimal design for microstructured surfaces with hydrophobic and hydrophilic materials

Cited 46 times inthomson ciCited 40 times inthomson ci
Title
Wetting transition and optimal design for microstructured surfaces with hydrophobic and hydrophilic materials
Author
Park, Chan IckJeong, Hoon EuiLee, Sung HoonCho, Hye SungSuh, Kahp Y.
Keywords
Capillary force; Microstructure; Polymer; Replica molding; Soft lithography; Wetting transition
Issue Date
2009-08
Publisher
ACADEMIC PRESS INC ELSEVIER SCIENCE
Citation
JOURNAL OF COLLOID AND INTERFACE SCIENCE, v.336, no.1, pp.298 - 303
Abstract
We present wetting transition of a water droplet on microstructured polymer surfaces using materials with different hydrophilicity or hydrophobicity: hydrophobic polydimethyl siloxane (PDMS) (θwater ∼ 110°) and hydrophilic Norland Optical Adhesive (NOA) (θwater ∼ 70°). The microstructures were fabricated by replica molding and self-replication with varying pillar geometry [diameter: 5 μm, spacing-to-diameter ratio (s/d): 1-10 (equal interval), height-to-diameter ratio (h/d): 1-5] over an area of 100 mm2 (10 mm × 10 mm). Measurements of contact angle (CA) and contact angle hysteresis (CAH) demonstrated that wetting state was either in the homogeneous Cassie regime or in the mixed regime of Cassie and Wenzel states depending on the values of s/d and h/d. These two ratios need to be adjusted to maintain stable superhydrophobic properties in the Cassie regime; s/d should be smaller than ∼7 (PDMS) and ∼6 (NOA) with h/d being larger than ∼2 to avoid wetting transition by collapse of a water droplet into the microstructure. Based on our observations, optimal design parameters were derived to achieve robust hydrophobicity of a microstructured surface with hydrophobic and hydrophilic materials.
URI
Go to Link
DOI
10.1016/j.jcis.2009.04.022
ISSN
0021-9797
Appears in Collections:
MEN_Journal Papers
Files in This Item:
2-s2.0-67349225935&.pdf Download

find_unist can give you direct access to the published full text of this article. (UNISTARs only)

Show full item record

qrcode

  • mendeley

    citeulike

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

MENU