Polystyrene-polyaniline core-shell composite particles using a bifunctional selectively polymerizable monomer as the interfacial linkage

Polystyrene-polyaniline core-shell composites were synthesized using a bifunctional monomer (benzenaminium 4-styrenesulfonate) as the interface. For the core synthesis, the monomer allowed the stabilization of styrene emulsion polymerizations, performing the function of a conventional reactive surfactant, copolymerizing with styrene by free radical polymerization. Then, the monomer allowed the synthesis of polyaniline in the emeraldine salt form by oxidative polymerization to obtain the shell. It was found that the particle size was inversely dependent on the monomer content, as established by the classical theory of emulsion polymerization. The product obtained is a complex system in which the core is a copolymer of styrene and styrenesulfonate and the shell is polyaniline with two doping agents. The polyaniline shell presented optical and electroactive properties, characterized by UV-vis spectroscopy and cyclic voltammetry. Finally, the core-shell was evaluated for H2S detection showing promising results for the design of electrochemical sensors.