Molecular crystals and liquid crystals · 1982 · 37 citations · 4 references
Natural SciencesChemistryMaterials ScienceOrganic ChemistryPolymer ChemistryPolymer MaterialsLiquid Crystal MaterialsLiquid CrystalsPolymer CharacterizationPolymer PhysicsPolymer StructurePolymer ThermodynamicsAromatic PolyamidesInterchain InteractionsIntramolecular Hydrogen BondingLiquid Crystal Phase BehaviorLiquid Crystalline PolymersMesophase StructurePolyamideThermotropic Liquid Crystals
Abstract The use of substituents (X # H) ortho to the amide nitrogen in both aromatic polyamides and analogous diamides renders these compounds to be enantiotropic mesogens by lowering the solid → mesophase temperature. At the molecular level this is understood as a reduction in interchain hydrogen bonding through either a steric blocking effect and/or through formation of intramolecular hydrogen bonds (when X = C1, OCH3). DSC, optical microscopy and infrared data are presented for the eight compounds reported.
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