Polymorphism of N-stearoylethanolamine:Differential scanning calorimetric, vibrational spectroscopic (FTIR), and crystallographic studies

Based on a series of physicochemical properties (differential scanning calorimetry, powder X-ray crystallographic studies and Fourier-transform infra red spectroscopic analysis) determined for N-stearoylethanolamine (NSEA) (C18:0) at different temperatures, evidence has been given that this compound can exist in (at least) three polymorphic forms. Powder X-ray crystallography clearly demonstrates the presence of three distinct molecular packings at distinct temperatures while spectral changes in the vibrational spectra reveal that the geometry of the CH(2)z.sbnd;CO functional group of the molecule is affected during the polymorphic transitions. Rationalization of the thermal physicochemical behavior of NSEA in terms of molecular packing is also proposed. It supposes rearrangement of the hydrocarbon chains upon heating of the molecule

Infrared Study on the Adsorption Behavior of Methylamine in a Series of Large Pore Cationic Zeolites: A Further Confirmation of Three Types of Interaction between Methylamine and Zeolites

The interaction of methylamine with a large series of 12R window cationic zeolites having different compensating ions and structures was discussed. The adsorption of methylamine was performed on self-supported zeolite wafer. The location of cations and zeolite structure modifies the strength of each kind of interaction and the overall interaction strength.</p