Investigation of the covalently attached multilayer architecture based on diazo-resins and poly(4-styrene sulfonate)

It is reported on the multilayer architecture containing a photo-reactive polyelectrolyte diazo-resins (DAR) as polycation and poly(4-styrene sulfonate) (PSS) as polyanion, held together by electrostatic interaction. Upon UV irradiation, the adjacent interfaces of the multilayer reacted to form a covalently crosslinking structure which greatly improved the stability of the films. These changes were confirmed by UV-VTS and FTIR spectroscopy. The thickness of the covalently attached films was characterized with X-ray diffraction, results from which showed that the thickness of the films can be adjusted in a nanometer scale by adding salts or diluting the solution of DAR. Atomic force microscopy (AFM) experiments showed that both the films before and after UV irradiation were closely compacted as well as smooth, with no obvious changes in morphology to be observed during the photoreaction. It was confirmed that this was an effective way to fabricate photosensitive and then stable layered nanoarchitecture.