77251-83-3Relevant articles and documents
Study of mesomorphism and its relation to molecular structure with special reference to central bridges viz. -COO- and -CH=CH-COO- of the homologous series
Sharma,Solanki,Patel,Patel
, p. 137 - 145 (2016/03/01)
Two ester homologous series of mesogens, viz., Methyl-p-(p′-n-alkoxy benzoyloxy) cinnamates (X) and Methyl-p-(p′-n-alkoxy cinnamoyloxy) cinnamates (Y) being structurally similar are discussed. Both (X) and (Y) differ in respect of central bridges linking two phenyl rings. Only enantiotropic nematogenic character is observed without exhibition of any smectic character by all members of series (X) and (Y). Thermal stability of series (X) is relatively low as compared to (Y), but nematogenic mesophase lengths are of reverse order. Solid-nematic/solid-isotropic and nematic-isotropic transition curves in the phase diagrams behave in normal manner.
Mesomorphism and molecular structure: Novel homologous series 4-(4′-n-alkoxy cinnamoyloxy)-4″-methoxy benzyl benzoates
Patel, Brijesh H.,Doshi
, p. 78 - 86 (2015/03/14)
A novel homologous series consists of 11 homologues, studied with a view to understand and establish the relations between mesomorphism and molecular structure of novel substances. All the novel members of a series except methoxy and pentyloxy homologue derivatives are liquid crystalline [LC] in nature. Mesomorphism commences from a second member of a series ethoxy, propyloxy, butyloxy, and hexyloxy to hexadecyloxy homologue derivatives are nematogenic while decyloxy, dodecyloxy, and tetradecyloxy homologue derivatives are smectogenic, in addition to nematogenic. All mesogenic homologues of a series are enantiotropic mesomorphic. Phase transition curve for Smectic-Nematic behave in normal manner without exhibition of odd-even effect, whereas nematic-isotropic transition curve adopts serpentile shape as rising and falling nature with exhibition of very minor odd-even effect. Textures of nematic phase are threaded or schlieren and that of a smectic mesophase is a focal conic fan shaped of the type smectic A or C. Analytical and spectral data supported molecular structures of homologues. The mesomorphic behaviors of present series are compared with a structurally similar other known series. Smectic and nematic thermal stabilities are 182.6 and 246.0°C, respectively. Present series is partly smectogenic and predominantly nematogenic with considerable degree of mesomorphism (maximum 100 °C) and high melting type.
Mesomorphism Dependence on Terminally Substituted End Group
Marathe, Rajesh B.,Doshi
, p. 1 - 8 (2015/12/30)
A novel homologous series of liquid crystalline substances has been synthesized and studied with a view to understanding and establishing the relation between liquid crystal properties and molecular structure. The novel ester series consists of eleven enantiotropically smectogenic homologous without exhibition of nematogenic property. Transition temperatures were determined with an optical polarizing microscope equipped with a heating stage. Textures of smectic mesophase are focal conic fan shaped of smectic A or C type. Analytical and spectral data confirms the molecular structures of homologous. Transition curve, Cr-Sm behaved in normal manner. Transition curve Sm-I behaved in a normal manner up to the octyloxy (C8) homolog derivative and then behaved in the unusual manner for the C10, C12, C14, and C16 derivatives. An odd-even effect is observed for the Sm-I transition curve. The series entirely smectogenic with a middle-ordered melting type and a moderate mesophase length. The average thermal stability for smectic is 128.09°C and mesophase length ranges from 8.6°C to 73.2°C. The mesomorphic (LC) behavior of the novel series is compared with structurally similar known homologous series.
