Synthesis of Symmetric Liquid Crystal Dimers Based on 1,2-bis{-[-(4-alkoxybenzoyloxy)benzylidene]amino)phenoxy}ethane and Investigation of Phase Behaviour by Varying Alkoxy Terminal Chain Length

Autor:	Hyun Hoon Song, B. Ramaraj, Chang Sin Lee, Seok Gn Ryu, Soo-Min Lee, Tae Hyeong Kim, Kuk Ro Yoon
Rok vydání:	2008
Předmět:	Schiff base General Chemistry Condensed Matter Physics Photochemistry chemistry.chemical_compound Crystallography Differential scanning calorimetry chemistry Liquid crystal Phase (matter) Diamine Alkoxy group Proton NMR General Materials Science Spectroscopy
Zdroj:	Molecular Crystals and Liquid Crystals. 492:117/[481]-129/[493]
ISSN:	1563-5287 1542-1406
DOI:	10.1080/15421400802331091
Popis:	With the objective to study the effect of alkoxy terminal chain length on mesomorphic properties of liquid crystals, We have synthesized ester and Schiff base dimers from diamine derivative containing 1,2-dioxyethylene as short spacer with aldehyde derivatives having different lengths of terminal alkoxy chains (n = 6–12). The chemical structure of the final products was investigated by fourier transform infrared (FT-IR) spectroscopy and proton nuclear magnetic resonance (1H NMR) spectroscopy. The mesomorphic properties and optical textures of the resultant dimers were characterized by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). It was found that all the dimers show mesomorphic properties and the increase in terminal alkoxy chain length has pronounced effect on the mesomorphic properties. The temperature range of smectic phase window widens and nematic-isotropic phase window narrows sharply with increasing alkoxy chain length.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::6f5a5b2a844e3acf812d5731481bd12c https://doi.org/10.1080/15421400802331091 Zobrazit plný text záznamu