Improved electro-optical and dielectric properties of polymer dispersed liquid crystal doped with disperse dye red 1 and carbon nanoparticles

ABSTRACT

Disperse dye red 1 (DR1) and carbon nanoparticles (CNPs) were doped separately to form polymer dispersed liquid crystal films, namely, DPDLC & CPDLC. Nematic liquid crystal (LC) and photopolymer NOA-65 were used to prepare these composite films using polymerisation-induced phase separation (PIPS) technique. In this research work, it is demonstrated that the minute concentration (0.05% wt./wt.) of DR1 and CNPs controls the LC droplet alignment and LC droplet size in polymer dispersed liquid crystal (PDLC) film. The effect of DR1 and CNPs on PDLC film has been investigated in terms of LC droplet size, transition temperature, voltage-transmittance characteristic, contrast ratio, response time, haze, and dielectric measurements. The obtained results reveal that the threshold voltage values of the composite film get reduced from 34.87 V (undoped) to 10.19 and 9.26 V, for 0.05% of DR1 and CNPs doping, respectively. The DR1 (0.05%) doped film shows improved contrast of the undoped film as compared to CNPs (0.05%) film, whereas CNPs (0.05%) doped film shows a faster response time of 2.81 ms as compared to DR1 (0.05%) doped film (3.14 ms). Dielectric analysis of undoped, DPDLC, and CPDLC films represents Debye type relaxation mode.

GRAPHICAL ABSTRACT

KEYWORDS:

• Polymer dispersed liquid crystal
• disperse dye red 1 (DR1)
• carbon nanoparticles (CNPs)
• electro-optical
• dielectric analysis

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.

AnujaKatariya-Jain: Methodology, Conceptualisation,Visualisation, Writing-Editing.

Prof R. R.Deshmukh: Conceptualisation, Supervision, Projectadministration, Writing- Reviewing.

Supplemental data

Supplemental data for this article can be accessed online at https://doi.org/10.1080/02678292.2023.2190171

Additional information

Funding

This research wassupported by the University GrantsCommission (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) for financial assistance.