Viscoelastic properties of a homologous series of nematic liquid crystalline Schiff's bases
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چکیده
2014 Experimental values are reported for the distortion viscoelastic and elastic ratios for a homologous series of nematic Schiff’s bases : APAPAm (m = 1-5, 9) and OHMBBA as a function of temperature. In the experiments the homodyne photoelectric self-beat technique was used to detect noise intensity spectra and to determine the angular distribution of laser light scattered by the nematic liquid crystals. Relations between the viscoelastic properties and the sizes of the molecules are discussed. It turned out that the viscosity coefficients are rather independent of the molecular sizes of the compounds studied. J. Physique 45 (1984) 1347-1360 AOÛT 1984,
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