Kinetics of β-phase formation in 1- O-alkylglycerols

Abstract

The rate of β-phase formation in the ether lipids 1- O-alkylglycerols have been investigated at various temperatures. The concentrations of the phases vs. time in 1- O-hexadecylglycerol (C 16G) were measured using automatic X-ray powder diffraction peak area measurements. In 1- O-decylglycerol (C 16G) the rate was estimated using the heat evolved during the transition. At least two factors are important for the low transition rate. At higher temperatures the rate appears to be limited by a low probability of β crystallite formation (nucleation). As the temperature is decreased, crystallite formation probably increases. A second factor involves an activation of the metastable lattice. The activation process results in a lower rate at decreased temperatures. The two factors together give the highest transition rate at the α ↔ sub-α-phase transition temperature.