Measurements of the real (&egr;′) and imaginary (&egr;″) parts of the dielectric constant have been made on polyvinyl stearate at temperatures from −50° to +80°C and over a frequency range from 100 to 50 000 cps. Although no full relaxation dispersion region has been found in this frequency range, there are indications of the beginnings of a high‐frequency dispersion region just above the freezing point (49.1°C) in the liquid polymer. This dispersion cuts off or is ``frozen in'' rapidly as the sample freezes, giving evidence of a slight rotational freedom in the solid polymer near the freezing and melting points. Because of this ``freezing in'' of the dispersion mechanism it is supposed that the dipolar side chain is unable to rotate in the solid form because of the combined effects of the side‐chain crystalline field and angle which the C&sngbnd;O bond (between the main chain and side chain of the polymer) makes with the side‐chain axis. Specific volume measurements were made to supplement the above work. The measurements show that a quickly frozen sample will melt at a lower temperature (52.5°C) than a slowly frozen sample (55.0°C). Also, discontinuities in the slope of the specific volume vs temperature curve are related to changes in the imaginary part of the dielectric constant and to changes in mechanical dispersion data. The above results are compared with those for other polymers.