Preparation and Orthogonal Analysis for Dual-Responsive Electrochromic Polymer Dispersed Liquid Crystal Devices

Abstract

In this work, we provide a fabrication method for dual-responsive electrochromic (EC) polymer dispersed liquid crystal (PDLC) devices. The EC PDLC device was developed by combing the PDLC technique and a colored complex formed via a redox reaction without a specific EC molecule in a simple preparation method. The mesogen played dual roles in the device for scattering in the form of microdroplets and participating in the redox reactions. Orthogonal experiments were performed with the acrylate monomer concentration, the ionic salt concentration, and the cell thickness as factors to investigate the electro-optical performance for the achievement of optimized fabrication conditions. The optimized device presented four switchable states modulated by external electric fields. The light transmittance of the device was changed by an alternative current (AC) electric field while the color change was realized by a direct current (DC) electric field. Variations of mesogen and ionic salt species can modulate the color and hue of devices, which solves the disadvantage of a single color for traditional EC devices. This work lays the foundation for realizing patterned multi-colored patterned displays and anti-counterfeiting via screen printing and inkjet printing techniques.

The effect of high dielectric BaTiO3 nanoparticle dimensions on the dielectric properties and electro-optical performance of polymer dispersed liquid crystal films

“…In the absence of an electric field, the PDLC film exhibits high light scattering (OFF state) due to the refractive index mismatch between the polymer matrix and LC. Conversely, when an electric field is applied, LC molecules align along the field direction, 5 rendering the PDLC film transparent (ON state) as a result of the matched refractive indices of the polymer matrix and LC. 6–9 To achieve this alignment, a high voltage is required to counteract the strong anchoring force between the polymer matrix and LC.…”