Thermodynamic properties of dimethyl phthalate along the (vapour plus liquid) saturation curve

Measurements of vapour pressure p, density rho, and molar heat capacity C-p ,C-m are reported for dimethyl phthalate in the liquid phase. The methods o f comparative ebulliometry, vibrating-tube densimetry, and heat conduction calorimetry were employed to determine these properties. A simultaneous cor relation of vapour pressures and of enthalpy of vaporization Delta(vap)H(m) was used to generate parameters for the Cox equation. Vapour pressure and enthalpies of vaporization derived from the fit are reported at the triple point temperature T-t, at T = 298.15 K, and at the normal boiling temperatu re. For inclusion into program packages, parameters of the Antoine equation were calculated by fitting the ebulliometric vapour pressures. A compariso n of all measured properties with literature data is presented. (C) 1999 Ac ademic Press.