Layer-by-layer thin films of polyaniline alternated with natural rubber and their potential application as a chemical sensor

Self-assembled films of polyaniline (PAni) alternated with natural rubber (NR) were successfully produced by layer-by-layer self-assembly technique (LbL), by using the latex of natural rubber obtained from the Hevea-brasiliensis tree. The centrifuged NR latex was used without any previous treatment. The influence of pH on the adsorption kinetics and film growth was evaluated. The films presented a typical linear growth, showing a constant adsorption of material in each deposition step. The FTIR spectroscopy study confirmed the presence of rubber chains (cis-1,4-poly-isoprene) on the LbL films. The morphological characterizations showed great roughness and a spherical shape of the NR particles as a predominant characteristic on the film’s surface. Finally, the potential use of the films as a chemical sensor was identified in our tests.