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Bio-inspired responsive polymer pillar arrays

Part of: Polymers and Soft Matter

Published online by Cambridge University Press:  22 April 2015

Elaine Lee  and
Shu Yang
Elaine Lee
Affiliation:
Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104, USA
Shu Yang*
Affiliation:
Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104, USA
*
Address all correspondence to Shu Yang atshuyang@seas.upenn.edu
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Abstract

High-aspect-ratio (HAR) pillar arrays offer large surface area, well-defined surface topography, and large mechanical compliance. In this Prospective, we showcase micro- and nanopillar array systems that exploit the responsiveness and/or harness the mechanical instabilities for myriad surface-mediated applications, including tunable wetting, adhesion, optical properties, and actuation. In each application, we start with biological examples with HAR pillar structures, and discuss strategies to fabricate responsive HAR polymer pillar structures. We then discuss approaches to tune the surface topography, such as via bending, tilting, expansion or contraction, and collapsing of the pillars, and the resulting change of surface and optical properties, and their dynamic actuation. In each system, we discuss the controllability and recoverability of pillar deformation.

Type
Polymers/Soft Matter Prospective Articles
Information
MRS Communications , Volume 5 , Issue 2 , June 2015 , pp. 97 - 114
Copyright
Copyright © Materials Research Society 2015 

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