Orientation order in monoethanolamine at 25–75°C, according to data from dielcometry

Abstract

The static permittivity (ɛs) of monoethanolamine (MEA) is measured at a frequency of 1 MHz in the temperature range of 20–90°C. The found data were analyzed in the context of the Onsager-Kirkwood-Frohlich theory. The values of the correlation factor (g) are calculated in the investigated temperature range. Similar calculations using literature data are performed for 3-amino-1-propanol (AP) and N,N-dimethylethanolamine (DMEA) (temperature range, 15–35°C). The difference between the correlation factors of MEA, AP, and DMEA and their temperature dependences are explained by the structures of these amino alcohols and their molecules. A conclusion is drawn on the orientation order in liquid MEA, based on the obtained results made. In addition, the data from our study of the equilibrium dielectric properties of MEA are compared to the similar properties of ethylene glycol (EG), and a conclusion is drawn on features of the structure of amino alcohol relative to diol.