Polymer Dispersed Liquid Crystals with elongated droplets as novel pressure sensors

ABSTRACT

Polymer-Dispersed Liquid Crystals, PDLCs, are formed by liquid crystal droplets embedded in a polymer matrix, which can assume different liquid crystal director configurations. The transition from one configuration to another one by the application of an external field (electric, magnetic or mechanical) allows to exploit interesting applications such as electro-optical devices or to develop theoretical models in the soft matter field. Pressure sensors represent a recent and important application of PDLCs. In this work, PDLCs with elongated droplets and radial configuration were obtained during the phase separation of the liquid crystal component from an elastomeric polymer in the presence of an AC external electric field. The application of pressure to the device causes deformation in the droplets shape and liquid crystal reorientation with a consequent variation in the overall electric resistance of the sample.

Graphical Abstract

KEYWORDS:

• PDLCs
• elastomer
• elongated nematic droplets
• electro-optical properties
• reorientation
• pressure sensors

Acknowledgments

MIUR, the Italian Ministry for University and Research is acknowledged for financial supports (EX 60%-2021).

The PhD of Mariafrancesca Baratta is funded by a scholarship from Regione Calabria (grant POR Calabria 2014-2020 - Azioni 10.5.6 e 10.5.12).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Ministero dell’Istruzione, dell’Università e della Ricerca [Ex 60%-2021].