111153-20-9Relevant academic research and scientific papers
Self-assembling behaviour of chiral calamitic monoacrylates targeted for polymer stabilisation of polar smectic phases in chiral liquid crystals
Dmochowska, Ewelina,Herman, Jakub,Czerwiński, Micha?,Stulov, Sergei,Bubnov, Alexej,Kula, Przemys?aw
, (2021/03/03)
The stabilisation and control of synclinic and anticlinic chiral liquid crystalline phases remain an actual and highlighted task. This work presents the design and mesomorphic properties of new chiral calamitic reactive mesogens, monoacrylates, based on biphenyl benzoate and phenyl biphenyl-4-carboxylate cores with reactive terminal groups placed far from the chiral chain. The compound's structures, compatible with the components of modern ferroelectric and antiferroelectric liquid crystalline mixtures, are confirmed by mass spectrometry (electron ionization) analysis and proton/carbon nuclear magnetic resonance. All the reactive mesogens possess the self-assembling, i.e. liquid crystalline behaviour with high tendency to create smectic phases in a broad temperature range, which was confirmed by a polarizing optical microscopy, differential scanning calorimetry and broad-band dielectric spectroscopy. Doping of advanced multicomponent mixtures possessing the chiral smectic phases by the designed monoacrylates with further cross-linking procedure, can be an effective and functional tool for stabilising ferroelectric and antiferroelectric phases in various states and hence, can allow the symmetrisation of the switching times in the modes employed surface stabilised geometry; this is a very highlighted task for optoelectronics. Moreover, an evident considerable tendency for thermal polymerisation of specific reactive mesogens can reduce the drawbacks of polymer stabilisation.
Synthesis and mesomorphic properties of achiral and chiral esters with high tilted synclinic and anticlinic phases
Gasowska,Dabrowski,Drzewinski,Kenig,Tykarska,Przedmojski
, p. 231/[1273]-241/[1283] (2007/10/03)
Two series of three ring esters with chiral chain (derivative of (S)-octanol-2) and achiral chain (the swallow type) with high tilted synclinic and anticlinic phases were chosen to studies. The aim of presented studies was to find how the changes of diffe
Orthoconic antiferroelectrics. Synthesis and mesomorphic properties of optically active (S)-(+)-4-(1-methylheptyloxycarbonyl)phenyl 4′-(fluoroalkanoyloxyalkoxy)biphenyl-4-carboxylates and 4′-(alkanoyloxyalkoxy)biphenyl-4-carboxylates
Drzewinski,Dabrowski,Czuprynski
, p. 273 - 284 (2007/10/03)
Convenient methods for preparing optically active (S)-(+)-4-(1-methylheptyloxycarbonyl)-phenyl 4′-(ω-perfluoroalkanoyloxyalkoxy)- and 4′-(ω-alkanoyloxyalkoxy)biphenyl-4-carboxylates and their intermediates have been described and discussed. The phase transitions of the prepared esters have been investigated by differential scanning calorimetry.
The synthesis and mesomorphic properties of some novel antiferroelectric liquid crystals
Hird, Michael,Goodby, John W.,Toyne, Kenneth J.,Gleeson, Helen F.,Peter Buxton,Seed, Alexander J.,Herbert, Mark R.
, p. 213 - 220 (2007/10/03)
Several esters have been synthesised that exhibit the antiferroelectric smectic C phase. The core structures, like virtually all antiferroelectric materials, are very similar to that of MHPOBC. Lateral fluoro substituents have been used to reduce melting points and to investigate their effect on mesomorphic properties, spontaneous polarisation and tilt angle. A new device format reported by Lagerwall requires antiferroelectric liquid crystals with a 45° tilt angle. Novel antiferroelectric materials were prepared with fluoro substituents in lateral positions and in a terminal chain to provide low melting points, high antiferroelectric phase stability, high spontaneous polarisation and tilt angles of up to 45°. The synthetic routes to the novel materials are discussed, and the transition temperatures, tilt angles and spontaneous polarisations are compared to those of known materials.
Ferroelectric and antiferroelectric liquid crystalline phases in some pyridine carboxylic acid derivatives
Kasthuraiah
, p. 1619 - 1625 (2007/10/03)
The synthesis and mesomorphic properties of two series of compounds viz. (S)-(+)-4-(1-methylheptyloxy)phenyl 4′-(6″-alkoxypyridine-3-carbonyloxy)benzoatesand(S)-(+)-1- methylheptyl4-[4′-(6″-alkoxypyridine-3-carbonyloxy)benzoyIoxy]- benzoates are reported; the homologues of the former series exhibit smectic A and smectic C* phases while the derivatives of the latter series show rich polymesomorphism including the antiferroelectric phase. The mesophases have been characterised by using optical polarising microscopy and differential scanning calorimetric methods. Some physical properties such as the spontaneous polarisation, helical pitch, tilt angle and relative permittivity of two derivatives have also been investigated.
New chiral tolane series with antiferroelectric properties
Cluzeau,Nguyen,Destrade,Isaert,Barois,Babeau
, p. 69 - 91 (2007/10/02)
A new series of chiral tolane with aliphatic end chains ranging from heptyloxy to dodecyloxy has been synthesized and characterized. The mesomorphic properties have been analyzed by optical microscopy on pure compounds and mixtures, D.S.C, electro-optical
Optically active naphthalene compounds and liquid crystal materials and devices incorporating them
-
, (2008/06/13)
Optically active naphthalene compounds having the formula: STR1 in which X and Y are selected from combinations (a), (b) and (c): (a) X is C1-10 alkyl or alkoxy and Y is C4-16 optically active alkyl, (b) X is C1-10 alkyl o
