Langmuir. 2014 Feb 11;30(5):1435-43. doi: 10.1021/la404248d. Epub 2014 Jan 31.

Mechanically robust superhydrophobic polymer surfaces based on protective micropillars.

Langmuir : the ACS journal of surfaces and colloids

Eero Huovinen, Laura Takkunen, Tarmo Korpela, Mika Suvanto, Tuula T Pakkanen, Tapani A Pakkanen

PMID: 24483340 DOI: 10.1021/la404248d

Abstract

Considerable attention is currently being devoted less to the question of whether it is possible to produce superhydrophobic polymer surfaces than to just how robust they can be made. The present study demonstrates a new route for improving the mechanical durability of water-repellent structured surfaces. The key idea is the protection of fragile fine-scale surface topographies against wear by larger scale sacrificial micropillars. A variety of surface patterns was manufactured on polypropylene using a microstructuring technique and injection molding. The surfaces subjected to mechanical pressure and abrasive wear were characterized by water contact and sliding angle measurements as well as by scanning electron microscopy and roughness analysis based on optical profilometry. The superhydrophobic polypropylene surfaces with protective structures were found to maintain their wetting properties in mechanical compression up to 20 MPa and in abrasive wear tests up to 120 kPa. For durable properties, the optimal surface density of the protective pillars was found to be about 15%. The present approach to the production of water-repellent polymer surfaces provides the advantages of mass production and mechanical robustness with practical applications of structurally functionalized surfaces.

Publication Types

• Journal Article