Light-regulated molecular diffusion in a liquid crystal network

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Photo-responsive liquid crystal polymer networks offer promising means to generate useful functional devices, but many of them focus on their mechanical response so as to generate surface features or shape change. Here, we investigate the photomechanical effect of the polymer network for molecular transport purposes. Dual wavelength illumination of an azobenzene-functionalized cholesteric liquid crystal polymer film produces excess free volume within the film, which results in an accelerated molecular diffusion through the film. Moreover, the polarization of the UV light exposure on the cholesteric network plays an important role in a remarkable enhancement of molecular diffusion. When linearly polarized UV light rotates along with the twist of the helical axis of the cholesteric polymer, excess free volume forms sequentially from the diffusion network toward the dry network in the polymer. It works in concert with the concentration gradient of the diffusant and greatly improves the diffusion through the film.

LanguageEnglish
Pages4737-4742
Number of pages6
JournalSoft Matter
Volume15
Issue number23
DOIs
StatePublished - 1 Jan 2019

Fingerprint

Liquid Crystals
molecular diffusion
liquid crystals
Polymers
Free volume
polymers
Ultraviolet radiation
Cholesteric liquid crystals
photomechanical effect
Polymer films
Lighting
Polarization
Wavelength
illumination
gradients
augmentation
polarization
wavelengths
liquid crystal polymer

Cite this

@article{e2293379081848c78c8a83f1c941fad9,
title = "Light-regulated molecular diffusion in a liquid crystal network",
abstract = "Photo-responsive liquid crystal polymer networks offer promising means to generate useful functional devices, but many of them focus on their mechanical response so as to generate surface features or shape change. Here, we investigate the photomechanical effect of the polymer network for molecular transport purposes. Dual wavelength illumination of an azobenzene-functionalized cholesteric liquid crystal polymer film produces excess free volume within the film, which results in an accelerated molecular diffusion through the film. Moreover, the polarization of the UV light exposure on the cholesteric network plays an important role in a remarkable enhancement of molecular diffusion. When linearly polarized UV light rotates along with the twist of the helical axis of the cholesteric polymer, excess free volume forms sequentially from the diffusion network toward the dry network in the polymer. It works in concert with the concentration gradient of the diffusant and greatly improves the diffusion through the film.",
author = "Anping Cao and {van Raak}, {Roel J.H.} and Broer, {Dirk J.}",
year = "2019",
month = "1",
day = "1",
doi = "10.1039/c9sm00428a",
language = "English",
volume = "15",
pages = "4737--4742",
journal = "Soft Matter",
issn = "1744-683X",
publisher = "Royal Society of Chemistry",
number = "23",

}

Light-regulated molecular diffusion in a liquid crystal network. / Cao, Anping; van Raak, Roel J.H.; Broer, Dirk J.

In: Soft Matter, Vol. 15, No. 23, 01.01.2019, p. 4737-4742.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Light-regulated molecular diffusion in a liquid crystal network

AU - Cao,Anping

AU - van Raak,Roel J.H.

AU - Broer,Dirk J.

PY - 2019/1/1

Y1 - 2019/1/1

N2 - Photo-responsive liquid crystal polymer networks offer promising means to generate useful functional devices, but many of them focus on their mechanical response so as to generate surface features or shape change. Here, we investigate the photomechanical effect of the polymer network for molecular transport purposes. Dual wavelength illumination of an azobenzene-functionalized cholesteric liquid crystal polymer film produces excess free volume within the film, which results in an accelerated molecular diffusion through the film. Moreover, the polarization of the UV light exposure on the cholesteric network plays an important role in a remarkable enhancement of molecular diffusion. When linearly polarized UV light rotates along with the twist of the helical axis of the cholesteric polymer, excess free volume forms sequentially from the diffusion network toward the dry network in the polymer. It works in concert with the concentration gradient of the diffusant and greatly improves the diffusion through the film.

AB - Photo-responsive liquid crystal polymer networks offer promising means to generate useful functional devices, but many of them focus on their mechanical response so as to generate surface features or shape change. Here, we investigate the photomechanical effect of the polymer network for molecular transport purposes. Dual wavelength illumination of an azobenzene-functionalized cholesteric liquid crystal polymer film produces excess free volume within the film, which results in an accelerated molecular diffusion through the film. Moreover, the polarization of the UV light exposure on the cholesteric network plays an important role in a remarkable enhancement of molecular diffusion. When linearly polarized UV light rotates along with the twist of the helical axis of the cholesteric polymer, excess free volume forms sequentially from the diffusion network toward the dry network in the polymer. It works in concert with the concentration gradient of the diffusant and greatly improves the diffusion through the film.

UR - http://www.scopus.com/inward/record.url?scp=85067244566&partnerID=8YFLogxK

U2 - 10.1039/c9sm00428a

DO - 10.1039/c9sm00428a

M3 - Article

VL - 15

SP - 4737

EP - 4742

JO - Soft Matter

T2 - Soft Matter

JF - Soft Matter

SN - 1744-683X

IS - 23

ER -