| abstract |
AZO AND AZOXY COMPOUNDS OF THE FORMULA (4-R-PHENYL)-X-(1,4-PHENYLENE)-O-R'' WHEREIN X IS AZO OR AZOXY, R IS STRAIGHT-CHAIN ALKYL OF 1-8 CARBON ATOMS, AND R'' IS STRAIGHT-CHAIN ALKYL OR STRAIGHT-CHAIN ALKANOYL, EACH OF 1-10 CARBON ATOMS, IN PURE FORM AND MIXTURES THEREOF WITH EACH OTHER AND WITH OTHER NEMATIC OR NON-NEMATIC COMPOUNDS, HAVE NEMATIC LIQUID-CRYSTALLINE PHASES AT LOW TEMPERATURES AND EXHIBIT WIDE NEMATIC MESOPHASES. IN THEIR NEMATIC PHASE, THEIR LIGHT SCATTERING PROPERTY VARIES PROPORTIONATELY AND REVERSABLY TO THE VOLTAGE APPLIED THERETO, WHICH RENDERS THEM USEFUL IN THE PRODUCTION OF DISPLAY SCREENS IN NUCLEAR RESONANCE AND ELECTRON RESONANCE SPECTROSCOPY AND AS SOLVENTS FOR STEREOSPECIFIC CHEMICAL REACTIONS. |