VISCOSITY OF ISOMERIC OCTYL ALCOHOLS AS A FUNCTION OF TEMPERATURE AND PRESSURE

The viscosity of 2- and 3-octanol and 6-methyl-3-, 5-metlyl-3-, and 2-methyl-3-heptanol has been measured as a function of temperature (- 20°-80°C) and pressure (0-4 kbar). Specific structural differences exist in the temperature and pressure coefficients of isobaric viscosity; these differences are minimized, but still exist, when isochoric viscosities are compared. Viscous flow and dielectric relaxation of these liquids are compared, and it is concluded that the rate-determining steps are dissimilar. A previously proposed pressureinduced liquid structure transformation in these liquids could not be verified viscometrically.