Synthesis, characterization and structure-mesomorphic properties relationship of palm-based azo-ester bridged liquid crystals from caprylic acid
Document Type
Article
Publication Date
9-1-2023
Abstract
This paper discussed the liquid crystal properties of a new homologous series derived from palm caprylic acid that differ in terms of terminal substituents. The chemical structures of synthesized compounds were characterized by nuclear magnetic resonance (NMR), fourier transform infrared (FT-IR) and CHN elemental analysis, while the mesomorphic behaviors were evaluated by polarized optical microscopy (POM) and differential scanning calorimetry (DSC). The insertion of a polar substituent i.e. -CH3 (BME), -OCH3 (BMO), -OCH2CH3 (BEO) at the sixth position on the benzothiazole ring was able to reveal broad nematogenic temperature ranges (65.60-141.48 degrees C). The nematic mesophase stability is in order of BEO > BMO > BME, with two of them revealing their mesophase characteristics at nearly room temperature. This finding endorses a strong association between polarity factor and mesomorphism which was confirmed through density function theory with the basis set of 6-311 G d,p. The molecules also exhibit relatively high thermal stability (218-312 degrees C). This finding might be helpful in future structure design of palm-based LCs, as well as encourage the efforts in utilizing palm oil as a renewable and cheaper resource alternative, particularly in non-edible areas such as oleochemical-related research and development.
Keywords
Palm fatty acids, Caprylic acid, Azo-ester, Nematic, Mesomorphic
Divisions
CHEMISTRY
Funders
Universiti Malaya (GPF054B-2018)
Publication Title
Industrial Crops and Products
Volume
199
Publisher
Elsevier
Publisher Location
RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS