ELECTRICAL CONDUCTANCE, DENSITY, VISCOSITY AND THERMAL-BEHAVIOR OF LEAD(II) AND ZINC(II) SALTS OF SOME UNSATURATED FATTY-ACIDS

Data are presented for the electrical conductance, density, viscosity and differential thermal analysis of the lead(II) and zinc(II) salts of cis-9-octadecenoic, trans-9-octadecenoic and 9,12-octadecadienoic acids. The data are compared with those of lead(II) and zinc(II) octadecanoates. The activation energies for conductance in these soaps are similar to those of the corresponding octadecanoates which suggest that the charge carriers are the metal ions. However, the activation energies for viscous flow in these soaps are much smaller than for the corresponding lead and zinc octadecanoates which suggests that the structure of the carboxylate anions is important in determining viscous flow. The soaps do not form mesophases but melt directly into the isotropic liquid. The values of the entropy changes accompanying the fusion of the zinc salts suggest either that zinc 9,12-octadecadienoate is more ordered in the liquid phase or more disordered in the crystal phase than zinc octadecanoate or the zinc salts of cis- and trans-9-octadecenoic acids. © 1979.