Physico-chemical properties of sulfur : IV. Critical polymerization temperatures and polymerization equilibrium constants of sulfur

Abstract

The critical transition temperature, at which the production of sulfur polymer starts abruptly, changes with the dilution of sulfur by inactive diluent. As to this process, some data obtained by measuring the viscosity-temperature behavior in a viscometer have already been reported by the author. By analysing these data by means of the equation of the degree of polymerization obtained by Tobolsky et al., the author succeeded to get the polymerization equilibrium constants of sulfur, independent of the data of Tobolsky et al. The equilibrium constants thus obtained are somewhat lower than those of Tobolsky et al. The plots of the logarithm of equilibrium constant vs. the reciprocal of absolute temperature become a straight line. From the slope and the intercept of this straight line, the numerical values of ΔH and ΔS for the polymerization of sulfur were obtained as 2790cal, mole^-1 and 2.61cal. deg^-1 mole^-1, respectively.