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http://dx.doi.org/10.17661/jkiiect.2021.14.5.362

Liquid crystal alignment on rubbed self-assembled monolayers according to alkyl chain length  

Park, Hong-Gyu (Department of Electrical, Electronic and Control, Changwon National University)
Park, Mu-Hun (Department of Electrical, Electronic and Control, Changwon National University)
Publication Information
The Journal of Korea Institute of Information, Electronics, and Communication Technology / v.14, no.5, 2021 , pp. 362-368 More about this Journal
Abstract
A homeotropic liquid crystal (LC) alignment state on rubbed fluorinated self-assembled monolayers (FSAMs) is described according to alkyl chain length. A simple procedure, gas-phase method, for the preparation of FSAM was used. The average optical transmittance in the visible light range of FSAMs were 76.63% to 78.21%, which were superior to the conventional polyimide layer having a transmittance of 75.89%. In addition, the excellent homeotropic LC alignment characteristics of FSAMs were observed through pretilt angle measurement and polarized optical microscope images. By measuring the contact angles and the surface energies of FSAMs, it was confirmed that pretilt angles of LC molecules increased according to the alkyl chain length. High optical transparency and uniform homeotropic LC alignment characteristics of FSAMs showed the possibility of FSAMs as an LC alignment layers.
Keywords
Alkyl chain length; Homeotropic; Liquid crystals; Liquid crystal alignment; Self-assembled monolayer;
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