title: Printable optical sensors based on H-bonded supramolecular cholesteric liquid crystal networks.
abstract: A printable H-bonded cholesteric liquid crystal (CLC) polymer film has been fabricated that, after conversion to a hygroscopic polymer salt film, responds to temperature and humidity by changing its reflection color. Fast-responding humidity sensors have been made in which the reflection color changes between green and yellow depending on the relative humidity. The change in reflection band is a result of a change in helix pitch in the film due to absorption and desorption of water, resulting in swelling/deswelling of the film material. When the polymer salt was saturated with water, a red-reflecting film was obtained that can potentially act as a time/temperature integrator. Finally, the films were printed on a foil, showing the potential application of supramolecular CLC materials as low-cost, printable, battery-free optical sensors.
authors.affiliation: Functional Organic Materials & Devices, Eindhoven University of Technology, PO Box 513, Eindhoven, The Netherlands.
authors.forename: Nicole
authors.initials: N
authors.lastname: Herzer
authors.forename: Hilal
authors.initials: H
authors.lastname: Guneysu
authors.forename: Dylan J D
authors.initials: DJ
authors.lastname: Davies
authors.forename: Derya
authors.initials: D
authors.lastname: Yildirim
authors.forename: Antonio R
authors.initials: AR
authors.lastname: Vaccaro
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Broer
authors.forename: Cees W M
authors.initials: CW
authors.lastname: Bastiaansen
authors.forename: Albertus P H J
authors.initials: AP
authors.lastname: Schenning