Vapor pressure and enthalpy of vaporization of linear aliphatic alkanediamines

Vapor pressures and the molar enthalpies of vaporization of the linear aliphatic alkanediamines H2N–(CH2)n–NH2 with n = (3 to 12) have been determined using the transpiration method. A linear correlation of enthalpies of vaporization (at T = 298.15 K) of the alkanediamines with the number n and with the Kovat’s indices has been found, proving the internal consistency of the measured data.

► We measured vapor pressure of diamines H2N–(CH2)n–NH2 with n = 3 to 12.
► Vaporization enthalpies at 298 K were derived.
► We examined consistency of new and available in the literature data.
► Enthalpies of vaporization show linear dependence on numbers n.
► Enthalpies of vaporization correlate linearly with Kovat’s indices.