Odd–even effect on SmC* formation in chiral liquid crystal dimers
摘要:
A homologues series of chiral symmetric dimer was prepared from (S)-2-(6-methoxy-2-naphthyl)propionic acid. Structural effects on the mesomorphic and physiochemical properties were investigated in terms of variation in spacer length between two mesogenic units. The mesophase textures and their corresponding transition temperatures were identified by polarised optical microscopy and DSC measurements. The prepared dimeric compounds exhibit BP, N*, SmA* and SmC*/SmB* mesophase sequence. An odd-even effect was observed in forming tilted smectic phases with various length of spacers. Compounds containing even numbers of methylene spacer form SmC* mesophase, whereas odd spacers exhibited SmB* textures. Spontaneous polarisation was measured and maximum of 33.5 nC/cm(-1) was observed for BDPNP-6. (c) 2005 Elsevier B.V. All rights reserved.
Odd–even effect on SmC* formation in chiral liquid crystal dimers
摘要:
A homologues series of chiral symmetric dimer was prepared from (S)-2-(6-methoxy-2-naphthyl)propionic acid. Structural effects on the mesomorphic and physiochemical properties were investigated in terms of variation in spacer length between two mesogenic units. The mesophase textures and their corresponding transition temperatures were identified by polarised optical microscopy and DSC measurements. The prepared dimeric compounds exhibit BP, N*, SmA* and SmC*/SmB* mesophase sequence. An odd-even effect was observed in forming tilted smectic phases with various length of spacers. Compounds containing even numbers of methylene spacer form SmC* mesophase, whereas odd spacers exhibited SmB* textures. Spontaneous polarisation was measured and maximum of 33.5 nC/cm(-1) was observed for BDPNP-6. (c) 2005 Elsevier B.V. All rights reserved.
Synthesis and mesomorphic behavior of symmetrical chiral liquid crystal dimers incorporating ester linked biphenyl- naphthyl cores and terminal vinyl group
作者:Lakshmi C. Kasi Viswanath、Sengodan Senthil
DOI:10.1080/15421406.2017.1386518
日期:2017.10.13
ABSTRACT A series of symmetrical chiral, liquidcrystal dimeric molecules possessing ester- linked, biphenyl-naphthyl cores with varied spacer lengths and terminal vinyl groups have been synthesized using Naproxen as the synthetic precursor. The synthesized symmetrical chiral dimers were characterized by 1H NMR spectroscopy, and their liquid crystalline behavior was confirmed by DSC and HOPM studies.