Self-assembly ultrathin films based on diazoresins

A monolayer ultrathin film of nitro-containing diazoresin (NDR) was fabricated on mica via a self-assembly technique. The adsorption of NDR on mica at different deposition times was monitored by determining the absorbance of the NDR. It was confirmed that the deposition is rapid and reaches saturation within 2 min. The multilayer ultrathin films composed of NDR as polycation and poly(sodium-p-styrene sulfonate) (PSS) as polyanion were fabricated via layer-by-layer deposition. The surface morphology of the multilayer films was observed by atomic force microscopy (AFM). The results show that an ultrathin multilayer film can be obtained by the self-assembly technique. The multilayer films composed of NDR and PSS are photosensitive; under irradiation by UV light, the linkage nature between the layers converts from ionic to covalent, and, as a result, the stability of the film to polar solvents increases.