The interaction between erythritol and 4-hexylresorcinol during heating was investigated by thermal analysis, powder X-ray
diffractometry and infrared spectroscopy. A phase diagram was constructed by measuring the thermal behaviour of various resolidified
physical mixtures of erythritol and 4-hexylresorcinol. The phase diagram revealed complex formation between erythritol and
4-hexylresorcinol with incongruent melting at 84C; the stoichiometry was a molar raio of 1:2 erythritol:4-hexylresorcinol.
The complex gave diffraction peaks at 2θ=5.6 and 11.2 in the X-ray powder diffraction pattern. In the infrared spectrum,
a new peak due to the complex was observed at 3504 cm–1. The complex prepared by grinding and evaporation had the same molecular arrangement as the complex prepared by sealed heating.