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Title: A ferroelectric nematic liquid crystal vitrified at room temperature
Most of the current highly polar rod-shaped molecules that form ferroelectric nematic (NF) phase do so only at elevated temperatures and multicomponent mixtures are generally needed to obtain a broad and room temperature range NF phase. In this work, we describe the synthesis, phase characterization and measurement of various physical properties of a new ferroelectric nematic compound 4-[(4-nitrophenoxy)carbonyl]phenyl 2-isopropoxy-4-methoxybenzoate (RT11165). The molecular structure of RT11165 with a 2-isopropoxy group differs only by a substitution of the 2-methoxy group found in the prototype ferroelectric nematic material 4-[(4-nitrophenoxy)carbonyl]phenyl 2,4-dimethoxybenzoate (RM734). This small structure change produces a rather dramatic change in phase behavior leading to an NF phase from 63 °C down to room temperature. Below about 45°C the rotational viscosity of RT11165 increases critically and the temperature dependence indicates a glass transition at ~19°C. The transparent and polar glassy state of RT11165, which should be also piezoelectric, is a good candidate for energy storage, piezoecatalysis, data storage and other applications.  more » « less
Award ID(s):
2210083
PAR ID:
10522115
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Taylor and Francis
Date Published:
Journal Name:
Liquid Crystals
ISSN:
0267-8292
Page Range / eLocation ID:
1 to 9
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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