Layer-by-layer self-assembly of in-situ polymerized (PSS/PANI)_n composite films based on electrostatic interaction

The sodium polystyrene sulfonate (PSS) /polyaniline (PANI) composite films were prepared from
aniline (AN) monomers by in-situ polymerization , self2acid2doping and layer-by-layer self-assembly through the electrostatic force. In order to completely know the factors to control the nanostructure, the progress of polymerization of the PSS/PANI films was monitored by the UV-Vis spectra , and the influences of reaction conditions , such as subst rates , amount s of oxidant , and dipping time on the st ructure of PSS /PANI composite films were also stud2 ied. The (PSS/PANI) ncomposite films with different nanost ructures were then prepared at different aniline concen2 t rations. Atomic force microscope (AFM) , field emission scanning elect ron microscope (FESEM) and ellipsomet rywere employed to characterize the (PSS/ PANI)_n composite films. By optimizing the deposition conditions, the thickness of the PSS/ PANI bilayer was controlled within 40～100 nm and the electrical conductivity of the PSS/PANI bilayer was 2. 675 mS ·cm^-1. The uniform (PSS/PANI)₈ composite films were also prepared under the optimumconditions. The result s of the thermal gravimetry analysis (TGA) showed that the thermal stability of (PSS/PANI) ncomposite films was stronger than that of general PSS/PANI composite films.