title: Synthesis, characterization and texture observations of calamitic liquid crystalline compounds.
abstract: Several divinylic mesogenic monomers were synthesized based on coupling the monomer 4-(4-pentenyloxy)benzoic acid with chlorohydroquinone, 2,5-dihydroxy- acetophenone, methylhydroquinone or 2-methoxyhydroquinone. This resulted in novel mesogens of phenylene esters with different lateral substituent groups. The effect of the lateral substituent group on the thermotropic phase behavior for these liquid crystalline compounds was investigated using DSC and optical polarized microscopy. All the mesogens proved to have a wide nematic liquid crystalline range. Only the phenylene ester, which has a methoxy lateral substituent, exhibited both nematic and smectic phases. Structural confirmation of all new derivatives was accomplished by (1)H- and (13)C-NMR spectroscopic analysis, along with CH elemental analysis.
authors.affiliation: Department of Chemistry; University of Central Florida, P.O. Box 162366, Orlando, FL 32816- 2366, USA.
authors.forename: Maher A
authors.initials: MA
authors.lastname: Qaddoura
authors.affiliation: Department of Chemistry; University of Central Florida, P.O. Box 162366, Orlando, FL 32816- 2366, USA.|CREOL, The College of Optics and Photonics, University of Central Florida, P.O. Box 162366, Orlando, FL 32816-2366, USA.
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Belfield
mesh_terms: D000098:Acetophenones / Q000737:chemistry; D019817:Benzoic Acid / Q000138:chemical synthesis / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D006873:Hydroquinones / Q000737:chemistry; D050866:Liquid Crystals / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D044367:Phase Transition; D013818:Thermogravimetry
chemical_list: D000098:Acetophenones; D006873:Hydroquinones; D019817:Benzoic Acid; C038699:acetophenone; C031927:hydroquinone