Abstract
Based on liquid crystal networks we developed 'smart' coatings with responsive surface topographies. Either by prepatterning or by the formation of self-organized structures they can be switched on and off in a pre-designed manner. Here we provide an overview of our methods to generate coatings that form surface structures upon the actuation by light. The coating oscillates between a flat surface and a surface with pre-designed 3D micro-patterns by modulating a light source. With recent developments in solid state lighting, light is an attractive trigger medium as it can be integrated in a device for local control or can be used remotely for flood or localized exposure. The basic principle of formation of surface topographies is based on the change of molecular organization in ordered liquid crystal polymer networks. The change in order leads to anisotropic dimensional changes with contraction along the director and expansion to the two perpendicular directions and an increase in volume by the formation of free volume. These two effects work in concert to provide local expansion and contraction in the coating steered by the local direction of molecular orientation. The surface deformation, expressed as the height difference between the activated regions and the non-activated regions divided by the initial film thickness, is of the order of 20%. Switching occurs immediately when the light is switched 'on' and 'off' and takes several tens of seconds.
| Original language | English |
|---|---|
| Title of host publication | Emerging Liquid Crystal Technologies X |
| Editors | L.-C. Chien, H.J. Coles, H. Kikuchi, I.I. Smalyukh |
| Publisher | SPIE |
| ISBN (Print) | 9781628414745 |
| DOIs | |
| Publication status | Published - 2015 |
| Event | 10th Emerging Liquid Crystal Technologies Conference (ELCT 2015) - San Francisco, United States Duration: 9 Feb 2015 → 11 Feb 2015 Conference number: 10 |
Publication series
| Name | Proceedings of SPIE |
|---|---|
| Publisher | SPIE: The International Society for Optical Engineering |
| Volume | 9384 |
Conference
| Conference | 10th Emerging Liquid Crystal Technologies Conference (ELCT 2015) |
|---|---|
| Abbreviated title | ELCT 2015 |
| Country | United States |
| City | San Francisco |
| Period | 9/02/15 → 11/02/15 |
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Keywords
- Dynamic
- Liquid crystal polymer networks
- Reversible
- Self-organizing
- Surface topographies
Cite this
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Surface dynamics and mechanics in liquid crystal polymer coatings. / Liu, D.; Broer, D.J.
Emerging Liquid Crystal Technologies X. ed. / L.-C. Chien; H.J. Coles; H. Kikuchi; I.I. Smalyukh. SPIE, 2015. 938406 (Proceedings of SPIE; Vol. 9384).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Academic › peer-review
TY - GEN
T1 - Surface dynamics and mechanics in liquid crystal polymer coatings
AU - Liu, D.
AU - Broer, D.J.
PY - 2015
Y1 - 2015
N2 - Based on liquid crystal networks we developed 'smart' coatings with responsive surface topographies. Either by prepatterning or by the formation of self-organized structures they can be switched on and off in a pre-designed manner. Here we provide an overview of our methods to generate coatings that form surface structures upon the actuation by light. The coating oscillates between a flat surface and a surface with pre-designed 3D micro-patterns by modulating a light source. With recent developments in solid state lighting, light is an attractive trigger medium as it can be integrated in a device for local control or can be used remotely for flood or localized exposure. The basic principle of formation of surface topographies is based on the change of molecular organization in ordered liquid crystal polymer networks. The change in order leads to anisotropic dimensional changes with contraction along the director and expansion to the two perpendicular directions and an increase in volume by the formation of free volume. These two effects work in concert to provide local expansion and contraction in the coating steered by the local direction of molecular orientation. The surface deformation, expressed as the height difference between the activated regions and the non-activated regions divided by the initial film thickness, is of the order of 20%. Switching occurs immediately when the light is switched 'on' and 'off' and takes several tens of seconds.
AB - Based on liquid crystal networks we developed 'smart' coatings with responsive surface topographies. Either by prepatterning or by the formation of self-organized structures they can be switched on and off in a pre-designed manner. Here we provide an overview of our methods to generate coatings that form surface structures upon the actuation by light. The coating oscillates between a flat surface and a surface with pre-designed 3D micro-patterns by modulating a light source. With recent developments in solid state lighting, light is an attractive trigger medium as it can be integrated in a device for local control or can be used remotely for flood or localized exposure. The basic principle of formation of surface topographies is based on the change of molecular organization in ordered liquid crystal polymer networks. The change in order leads to anisotropic dimensional changes with contraction along the director and expansion to the two perpendicular directions and an increase in volume by the formation of free volume. These two effects work in concert to provide local expansion and contraction in the coating steered by the local direction of molecular orientation. The surface deformation, expressed as the height difference between the activated regions and the non-activated regions divided by the initial film thickness, is of the order of 20%. Switching occurs immediately when the light is switched 'on' and 'off' and takes several tens of seconds.
KW - Dynamic
KW - Liquid crystal polymer networks
KW - Reversible
KW - Self-organizing
KW - Surface topographies
UR - http://www.scopus.com/inward/record.url?scp=84947705171&partnerID=8YFLogxK
U2 - 10.1117/12.2077795
DO - 10.1117/12.2077795
M3 - Conference contribution
AN - SCOPUS:84947705171
SN - 9781628414745
T3 - Proceedings of SPIE
BT - Emerging Liquid Crystal Technologies X
A2 - Chien, L.-C.
A2 - Coles, H.J.
A2 - Kikuchi, H.
A2 - Smalyukh, I.I.
PB - SPIE
ER -