To probe the structure of methanol and Aerosol OT (AOT) in AOT reverse micelles by FTIR measurements

Abstract

We have reported the study of methanol/AOT/n-heptane reverse micellar aggregates using Fourier Transform Infrared (FTIR) spectroscopy. We have divided our whole work into two parts. In the first part we have studied the structural properties of Aerosol OT (AOT) reverse micelles by monitoring the changes in the symmetrical sulfonate stretching region (1000–1100 cm⁻¹), asymmetrical sulfonate stretching region (1130–1330 cm⁻¹) and carbonyl frequency region (1695–1770 cm⁻¹), and in the other part we have measured the changes in the maximum position of OH stretching frequency region (3140–3650 cm⁻¹) with increasing methanol content of the reverse micellar solution. Finally we have defined and established the presence of different types of methanol inside the reverse micelle by splitting the OH frequency region using multiple Gaussian curve fitting. Though methanol is partially soluble in n-heptane, this work certainly proves the existence of stable methanol/AOT/n-heptane reverse micelles.