Next Article in Journal
Electro-Optical Properties of a Polymer Dispersed and Stabilized Cholesteric Liquid Crystals System Constructed by a Stepwise UV-Initiated Radical/Cationic Polymerization
Previous Article in Journal
Stepwise Homogeneous Melting of Benzene Phase I at High Pressure
Article Menu
Issue 6 (June) cover image

Export Article

Open AccessArticle

Vertical Liquid Crystal Alignment of Comb-Like Alkyl Hydroxybenzoate-Substituted Polystyrene

Department of Chemical Engineering, Dong-A University, 37 Nakdong-Daero 550beon-gil, Saha-gu, Busan 49315, Korea
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Crystals 2019, 9(6), 281;
Received: 9 May 2019 / Revised: 27 May 2019 / Accepted: 27 May 2019 / Published: 29 May 2019
(This article belongs to the Section Liquid Crystals)
PDF [6906 KB, uploaded 29 May 2019]


We investigated the liquid crystal (LC) alignment behaviors of butyl hydroxybenzoate-substituted polystyrene (PBHB#; # = 20, 40, 60, 80, and 100, where # indicates the molar fraction of butyl hydroxybenzoate in the side chain), methyl hydroxybenzoate-substituted polystyrene (PMHB100), and ethyl hydroxybenzoate-substituted polystyrene (PEHB100). Generally, LC cells made employing polymer films having longer alkyl groups in the side chain show vertical LC alignment. For instance, a LC cell fabricated with the PMHB100 film showed random planar LC alignment, while the LC cells made from the PEHB100 and PBHB100 films exhibited vertical LC alignment. Moreover, LC cells prepared from a polymer film having a higher molar content of butyl hydroxybenzoate in the side chain exhibited vertical LC alignment. The observed vertical LC alignment behaviors are closely related to the surface energy of these polymer films. For instance, vertical LC alignment was observed when the surface energy of the polymer film was less than ~43.86 mJ/m2, which could result from the nonpolar alkyl groups of the alkyl hydroxybenzoate moiety. The LC cell prepared from PBHB100 as the LC alignment layer showed good electro-optical characteristics such as voltage holding ratio, residual DC voltage, and alignment stability at 200 °C. View Full-Text
Keywords: liquid crystal; alignment; vertical; polystyrene; hydroxybenzoate liquid crystal; alignment; vertical; polystyrene; hydroxybenzoate

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Ju, C.; Kang, S.; Kim, T.; Park, C.; Kang, H. Vertical Liquid Crystal Alignment of Comb-Like Alkyl Hydroxybenzoate-Substituted Polystyrene. Crystals 2019, 9, 281.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Crystals EISSN 2073-4352 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top