Self-assembly films from diazoresin and carboxy-containing polyelectrolytes

Abstract

Multilayer films from diazoresin (I) and poly(sodium acrylate) (II) or a hydrolyzed maleic anhydride-styrene copolymer (III) have been fabricated on mica. During the fabrication process the absorbance of the film at 380 nm, which is the characteristic absorption of the diphenylamine 4-diazonium group of I, increases about 0.033 for each fabrication cycle. This means that the thickness of the film increases regularly. Under irradiation with UV light or heating, following the decomposition of the diazonium group, the ionic bond in the film structure converts to a covalent bond; this conversion was preliminarily verified by FTIR spectrum analysis. The stability of the different films (irradiated or unirradiated) was determined by UV-vis spectroscopy and the results show that the resistance of the film to etching by polar solvents increases significantly after bond conversion.