Programming Tilting Angles in Shape Memory Polymer Janus Pillar Arrays with Unidirectional Wetting against the Tilting Direction
Abstract
By coating a thin layer of metal, including gold and gold-palladium alloy, of different thickness on the deformed shape memory polymer (SMP) pillars, we manipulate the degree of recovery of the SMP pillars. Pillars of different tilting angles were obtained as a result of balancing the strain recovery energy of the SMP pillars that favor the original straight state and the elastic energy of the metal layers that prefer the bent state. With this selective coating of a metal layer on the tilted pillars, we report a unique anisotropic liquid spreading behavior, where the water droplet is fully pinned in the direction of pillar tilting but advances in the reverse direction. This phenomenon is explained by the interplay of the surface chemistry and topography.
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Epoxy-based SMP pillars covered with a thin film of Au or Au-palladium alloy (thickness 20 nm) ensure the material unidirectional wetting properties.
“Epoxybased SMP pillars covered with a thin film of Au or Au-palladium alloy (thickness of 20 nm) were also reported ensuring the material unidirectional wetting properties.”
From Shape-memory polymers for multiple applications in the materials world (2016) · cites this paper as [144]
An anisotropic liquid spreading behavior was recorded where the water droplets propagated in direction opposite to the pillar tilting.
“An anisotropic liquid spreading behavior was recorded where the water droplets propagated in direction opposite to the pillar tilting [144].”
From Shape-memory polymers for multiple applications in the materials world (2016) · cites this paper as [144]
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- Authors
- Chen, C.-M., Chiang, C.-L., & Yang, S.
- Affiliations
- University of Pennsylvania (US)
- Corresponding author
- Yang, Shu
- ORCID
- Yang, Shu
- Venue
- Langmuir
- Publisher
- American Chemical Society (ACS)
- Published
- 2015-08-25
- Volume
- 31
- Issue
- 35
- Pages
- 9523-9526
- ISSN
- 0743-7463 (ISSN-L)
- 1520-5827
- OpenAlex
- W1188956988
- Cited by
- 32
- References
- 36
- Citations by year
- 2026: 2 · 2025: 2 · 2024: 1 · 2023: 1 · 2022: 1 · 2021: 4 · 2020: 5 · 2019: 6 · 2018: 4 · 2017: 4 · 2016: 2
- FWCI
- 1.30
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Langmuir (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Materials Science › Surfaces, Coatings and Films › Surface Modification and Superhydrophobicity
- Physical Sciences › Engineering › Mechanical Engineering › Advanced Materials and Mechanics
- Physical Sciences › Engineering › Computational Mechanics › Fluid Dynamics and Thin Films
- Keywords
- shape memory polymers, metal coatings, gold, gold-palladium alloy, strain recovery, droplet pinning, surface chemistry, surface topography, pillar arrays
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