Enhancing morphological, electro-optical and dielectric properties of polymer-dispersed liquid crystal by doping of disperse Orange 25 dye in LC E7

ABSTRACT

In this work, we have investigated morphological, electro-optical and dielectric properties of disperse orange 25 dye-doped polymer-dispersed liquid crystal (DPDLC) films. The DPDLC film composed of monomer Norland optical adhesive (NOA 65), nematic liquid crystal (E7), and disperse orange 25 dye was prepared through the polymerisation-induced phase separation (PIPS) method. The polarising optical microscope (POM) has been utilised to observe the effect of dye concentration and voltage on liquid crystal (LC) droplet morphology. The electro-optical properties of such DPDLC films were studied at a fixed frequency of 200 Hz and different voltage and temperature conditions (0–100 V, 25–50°C). The change in absorbance value with varying dye concentration and the electric field was monitored through a UV-Vis spectrophotometer. Dielectric relaxation characteristics of DPDLC films were examined using a precision impedance analyser in the frequency range 20 Hz–20 MHz and temperature range 25–60°C. Debye and Cole-Cole fitting techniques were used to describe the dielectric properties of DPDLC films.

Graphical Abstract

KEYWORDS:

• DPDLC
• electro-optical
• thermo-optical
• hysteresis
• dielectric relaxation technique

Acknowledgments

Manoj Mhatre thanks CSIR-UGC (India) for providing fellowship to carry out this research leading to a Ph.D. degree. Dr. Anuja Katariya-Jain would like to thank the Department of Science & Technology (DST-WOS-A), India.

Disclosure statement

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

Authors’ contributions

Manoj M. Mhatre: Conducting research, Data curation, Investigation, Writing- draft preparation.

Dr. Anuja Katariya-Jain: Methodology, Conceptualization, Visualization, Writing-Editing.

Prof R. R. Deshmukh: Conceptualization, Supervision, Project administration, Writing- Reviewing.

Additional information

Funding

This research was supported by the University Grants Commission (UGC), through CSIR-UGC NET JUNE-2017 (527478), and Department of Science and Technology (DST-WOS-A), India, through SR/WOS/A/PM-91/2018 (G) through fellowships given to Manoj M. Mhatre and Dr Anuja Katareiya-Jain respectively.