Preprint Article Version 1 Preserved in Portico This version is not peer-reviewed

Evaluation of Surface-active Agent Hexadecyltrimethylammonium Bromide with Vertical Self-alignment Property to Align Liquid Crystals for Various Cell Gap Conditions

Version 1 : Received: 14 November 2022 / Approved: 15 November 2022 / Online: 15 November 2022 (06:29:59 CET)

A peer-reviewed article of this Preprint also exists.

Ma, J.-S.; Choi, J.-Y.; Shin, H.-J.; Lee, J.-H.; Oh, S.-W.; Kim, W.-S. An Evaluation of Surface-Active Agent Hexadecyltrimethylammonium Bromide with Vertical Self-Alignment Properties to Align Liquid Crystals for Various Cell Gap Conditions. Appl. Sci. 2022, 12, 12582. Ma, J.-S.; Choi, J.-Y.; Shin, H.-J.; Lee, J.-H.; Oh, S.-W.; Kim, W.-S. An Evaluation of Surface-Active Agent Hexadecyltrimethylammonium Bromide with Vertical Self-Alignment Properties to Align Liquid Crystals for Various Cell Gap Conditions. Appl. Sci. 2022, 12, 12582.

Abstract

We evaluated hexadecyltrimethylammonium bromide (HTAB) for use in radio frequency (RF) applications in which liquid crystals (LCs) are used in layered structures that have various cell gap conditions. HTAB is a surfactant that can self-align vertically on the surface of indium tin oxide (ITO) substrates, and can induce homeotropic alignment of the LCs. For implementing RF devices with HTAB and LCs, we should consider limitations caused by the design conditions which are different from conventional liquid crystal displays such as cell gap. We quantified the concentration of HTAB ([HTAB]) that is necessary to form and maintain a sufficiently dense vertical alignment of 5CB (4-Cyano-4'-pentylbiphenyl). The required [HTAB] for full-homeotropic alignment was proportional to the cell gap until it was too large to support the transfer of the surface alignment to the LC, due to the weak anchoring nature of HTAB. We also showed the phase-change characteristic of the LC mixture depended on [HTAB] for the design of RF devices driven by light or heat. This work may help to guide the development of new approaches to designing efficient RF devices that use LCs.

Keywords

homeotropic alignment; cell gap; self-alignment; liquid crystal phase shifter; antenna

Subject

Chemistry and Materials Science, Other

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our Diversity statement.

Leave a public comment
Send a private comment to the author(s)
* All users must log in before leaving a comment
Views 0
Downloads 0
Comments 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here.