The Behavior of ¿-A Isotherm with Increasing Amount of Calix[4]arene at Air–Water Interface (16 - 21)

Abstract

The surface pressure-mean molecular area (¿-A) isotherm of surfactant (Mat 7) wasobtained by using Langmuir-Blodgett technique. The characterization of Mat 7 Langmuirfilm was carried out in terms of ¿-A isotherm. The Langmuir monolayer was successfullyformed by spreading the Mat 7 solution directly at air-water interface. The optimumcondition such as the volume of surfactant loaded on thesubphase was studied. It isobserved that with increasing amount of Mat 7 on water surface, ¿-A isotherm shiftedtowards the left. The mean surface area occupied by each Mat 7 molecule was estimatedby extrapolating the linear portion of each curve (between 10 and 20 mN/m) to a surfacepressure equal to zero. The UV-Visible spectra of Mat 7 in chloroform showed a significant result. The absorption peak increased as more concentrated solution was added.