Thermodynamics of 1,4-diisocyanatobutane in the range from T → (0 to 360) K at standard pressure

The temperature dependence of heat capacity of 1,4-diisocyanatobutane in crystalline and liquid states was determined by precision adiabatic vacuum calorimetry in the temperature range (8 to 360) K at standard pressure mainly with an uncertainty of ±0.2%. Thermodynamic characteristics of fusion, the first and the second cryoscopic constants, the isochoric heat capacity Cv and its lattice Cv,lat, and atomic at Cv,at components were estimated. The data were used to calculate the standard thermodynamic functions Cp,m∘/R,Δ∘THm∘/R,Δ∘TSm∘/RandΦm∘/R=Δ∘TSm∘/R-Δ∘THm∘/TR (where R is the universal gas constant) over the range T → (0 to 360) K. The energy of combustion was measured at T = 298.15 K by the bomb calorimetry. The standard thermodynamic characteristics of formation, namely, the enthalpy ΔfHm∘, the entropy ΔfSm∘, the Gibbs function ΔfGm∘andlnKf∘ of 1,4-diisocyanatobutane were evaluated at T = 298.15 K.