Abstract:

To investigate the thermal characteristics of lac wax, melting point and enthalpy (ΔHm), crystallization enthalpy (ΔHc), and specific heat capacity change of lac wax (ΔCp) prepared with different organic solvents were analyzed using differential scanning calorimetry (DSC). Big differences were found in the thermal characteristics of lac wax prepared with different organic solvents: the melting point varied in the range of 67.10 － 84.84 ℃, the melting enthalpy 158.90 － 201.50 J/g, and the crystallization enthalpy 157.05－191.80 J/g. The melting and the crystallization enthalpy both were positively correlated with the melting point and the former was higher than the latter. The maximum specific heat capacity difference was found to be 16.716 J/g·K and the minimum 10.212 J/g·K, and there was no correlation between the specific heat capacity difference and the melting. It is feasible to use DSC to analyze qualitatively and quantitatively the thermal characteristics of lac wax.

Key words: lac wax, differential scanning calorimetry (DSC), thermal characteristics