185993-18-4Relevant academic research and scientific papers
Synthesis and physical properties of thioester liquid crystals that exhibit an anti-ferro-anti phase sequencing
Nassif, Larissa,Jakli, Antal,Seed, Alexander J.
, p. 171 - 179 (2001)
The thioester unit has been commonly used to enhance the mesophase thermal stability and phase range in numerous liquid crystal materials. In this paper we report the synthesis of a homologous series of thioesters with similar structures to AS620 {(S)-(+)
Ferro-, ferri- and antiferro-electric behaviour in a bent-shaped mesogen
Matharu, Avtar S.,Grover, Chrissie,Komitov, Lachezar,Andersson, Gunnar
, p. 1303 - 1310 (2007/10/03)
The synthesis of a novel bent-shaped, four-ring thiophene-based chiral liquid crystalline ester derived from 5-(4-n-decyloxyphenyl)thiophene-2- carboxylic acid and (S)-1-methylheptyl 4'-hydroxybiphenyl-4-carboxylate is reported, i.e., (S)-4'-(1-methylheptyloxycarbonyl)biphenyl-4-yl 5-(4-n- decyloxyphenyl)thiophene-2-carboxylate. Optical microscopy, differential scanning calorimetry, miscibility study, and complementary electro-optical and current response studies reveal the existence of the SmA*, SmC* ferroelectric, SmC* ferrielectric, SmC* antiferroelectric and SmI* antiferroelectric phase types. Another mesophase type possibly exists below SmI* antiferroelectric which generates a rapid electro-optic response. Comparison with the analogous three-ring compound, i.e., (S)-4-(1- methylheptyloxycarbonyl)phenyl 5-(4-n-decyloxyphenyl)thiophene-2-carboxylate increases the thermal stability by 95.8 °C and the SmI* antiferroelectric phase is observed in addition.
The synthesis and characterisation of a novel thiophene-based liquid crystal exhibiting ferro-, ferri- and antiferro-electric phase types
Byron, David J.,Komitov, Lachezar,Matharu, Avtar S.,McSherry, Ian,Wilson, Robert C.
, p. 1871 - 1878 (2007/10/03)
The synthesis and liquid crystal properties of (R)-(-)-4-(l-methylheptyloxycarbonyl)phenyl 5-(4-decyloxyphenyl)thiophene-2carboxylate is reported. This material exhibits the following phase types (°C): I 97.4 SA 92.2 Sc*81.4 ferri 78.8 antiferroelectric 48.6 glass state (characterised by thermal optical microscopy and differential scanning calorimetry). Results from electro-optical investigations, for example, field-induced transitions, temperature and voltage dependence and current and electro-optic response, clearly illustrate the presence of the Sc* ferro-, ferri- and antiferro-electric phase types.
