Static and Dynamic Control of Fingerprint Landscapes of Liquid Crystal Network Coatings

Wei Feng, Dirk J. Broer, Lucie Grebikova, Clemens Padberg, Julius G. Vancso, Danqing Liu

Research output: Contribution to journalReview articleAcademicpeer-review

Abstract

Surface topography variations of liquid crystal networks in their functional coatings provide unique properties in these systems. Chiral-nematic polymer coatings self-organize in a fingerprint texture with the molecular helices parallel to the substrate with alternating domains of molecular units with parallel and perpendicular director orientation as controlled by the concentration of a reactive chiral additive. Driven by surface-tension differences and altered by anisotropic polymerization shrinkage, the coating may form hills and valleys hundreds of nanometers in size with different molecular alignment. The director orientation in the corrugations could be controlled by monomer diffusion during polymerization. Polymerization in the presence of a dichroic dye gives topographic elevations in which the molecules are oriented along the normal. Polymerization by means of a dichroic photoinitiator gives topographic elevations in which the molecules align parallel to the surface. By balancing the monomer diffusion and anisotropic polymerization shrinkage, relatively flat surfaces are also achieved. The different surfaces exhibit distinct topographical deformations when subjected to external stimuli, such as an AC electric field. This method can be universally extended to LC polymers with other alignment configurations.

Original languageEnglish
JournalACS Applied Materials and Interfaces
DOIs
Publication statusE-pub ahead of print/First online - 6 Sep 2019

Fingerprint

Liquid Crystals
Liquid crystals
Polymerization
Coatings
Polymers
Monomers
Molecules
Molecular orientation
Surface topography
Crystal orientation
Surface tension
Coloring Agents
Dyes
Textures
Electric fields
Substrates

Keywords

  • dichroic molecules
  • electric field
  • fingerprint
  • liquid crystal networks
  • surface topography

Cite this

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title = "Static and Dynamic Control of Fingerprint Landscapes of Liquid Crystal Network Coatings",
abstract = "Surface topography variations of liquid crystal networks in their functional coatings provide unique properties in these systems. Chiral-nematic polymer coatings self-organize in a fingerprint texture with the molecular helices parallel to the substrate with alternating domains of molecular units with parallel and perpendicular director orientation as controlled by the concentration of a reactive chiral additive. Driven by surface-tension differences and altered by anisotropic polymerization shrinkage, the coating may form hills and valleys hundreds of nanometers in size with different molecular alignment. The director orientation in the corrugations could be controlled by monomer diffusion during polymerization. Polymerization in the presence of a dichroic dye gives topographic elevations in which the molecules are oriented along the normal. Polymerization by means of a dichroic photoinitiator gives topographic elevations in which the molecules align parallel to the surface. By balancing the monomer diffusion and anisotropic polymerization shrinkage, relatively flat surfaces are also achieved. The different surfaces exhibit distinct topographical deformations when subjected to external stimuli, such as an AC electric field. This method can be universally extended to LC polymers with other alignment configurations.",
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author = "Wei Feng and Broer, {Dirk J.} and Lucie Grebikova and Clemens Padberg and Vancso, {Julius G.} and Danqing Liu",
year = "2019",
month = "9",
day = "6",
doi = "10.1021/acsami.9b11928",
language = "English",
journal = "ACS applied materials & interfaces",
issn = "1944-8244",
publisher = "American Chemical Society",

}

Static and Dynamic Control of Fingerprint Landscapes of Liquid Crystal Network Coatings. / Feng, Wei; Broer, Dirk J.; Grebikova, Lucie; Padberg, Clemens; Vancso, Julius G.; Liu, Danqing.

In: ACS Applied Materials and Interfaces, 06.09.2019.

Research output: Contribution to journalReview articleAcademicpeer-review

TY - JOUR

T1 - Static and Dynamic Control of Fingerprint Landscapes of Liquid Crystal Network Coatings

AU - Feng, Wei

AU - Broer, Dirk J.

AU - Grebikova, Lucie

AU - Padberg, Clemens

AU - Vancso, Julius G.

AU - Liu, Danqing

PY - 2019/9/6

Y1 - 2019/9/6

N2 - Surface topography variations of liquid crystal networks in their functional coatings provide unique properties in these systems. Chiral-nematic polymer coatings self-organize in a fingerprint texture with the molecular helices parallel to the substrate with alternating domains of molecular units with parallel and perpendicular director orientation as controlled by the concentration of a reactive chiral additive. Driven by surface-tension differences and altered by anisotropic polymerization shrinkage, the coating may form hills and valleys hundreds of nanometers in size with different molecular alignment. The director orientation in the corrugations could be controlled by monomer diffusion during polymerization. Polymerization in the presence of a dichroic dye gives topographic elevations in which the molecules are oriented along the normal. Polymerization by means of a dichroic photoinitiator gives topographic elevations in which the molecules align parallel to the surface. By balancing the monomer diffusion and anisotropic polymerization shrinkage, relatively flat surfaces are also achieved. The different surfaces exhibit distinct topographical deformations when subjected to external stimuli, such as an AC electric field. This method can be universally extended to LC polymers with other alignment configurations.

AB - Surface topography variations of liquid crystal networks in their functional coatings provide unique properties in these systems. Chiral-nematic polymer coatings self-organize in a fingerprint texture with the molecular helices parallel to the substrate with alternating domains of molecular units with parallel and perpendicular director orientation as controlled by the concentration of a reactive chiral additive. Driven by surface-tension differences and altered by anisotropic polymerization shrinkage, the coating may form hills and valleys hundreds of nanometers in size with different molecular alignment. The director orientation in the corrugations could be controlled by monomer diffusion during polymerization. Polymerization in the presence of a dichroic dye gives topographic elevations in which the molecules are oriented along the normal. Polymerization by means of a dichroic photoinitiator gives topographic elevations in which the molecules align parallel to the surface. By balancing the monomer diffusion and anisotropic polymerization shrinkage, relatively flat surfaces are also achieved. The different surfaces exhibit distinct topographical deformations when subjected to external stimuli, such as an AC electric field. This method can be universally extended to LC polymers with other alignment configurations.

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