Studies of spread monolayers of derivative of styrene[ndash ]maleic anhydride copolymers

Abstract

Reaction of alternating styrene–maleic anhydride copolymer with octadecylamine gave a half-ester of styrene–maleic anhydride copolymer which on further heating resulted in the polyimide. These form stable monolayers at an air/water interface and have been studied using the Π–A isotherms. The nature of the packing of the films and the behaviour of the hydrophobic chains as a function of surface density have been analyzed using photoelastic modulated Fourier transform infrared (PEM FTIR) spectroscopy for the Langmuir films at an air/water interface in the 3000–2700 cm^-1 region. The Langmuir–Blodgett (LB) films obtained from these monolayers are characterized by a high degree of two-dimensional ordering as demonstrated by the good packing seen by scanning tunnelling microscopy. In both the polymers, the alkyl chains are completely out of the water subphase, especially at high surface pressure, phenyl groups are almost completely submerged in the water.