Synthesis of sea urchin-like polystyrene/polyaniline microspheres by seeded swelling polymerization and their catalytic application

Polystyrene/polyaniline (PS/PANI) composite microspheres with sea urchin-like morphology, radial array of PANI nanofibers on the surface, are synthesized by seeded swelling polymerization with polystyrene (PS) microspheres as seed. The redox potential of the oxidants and the concentrations of reactants have important influences on the morphology of the obtained composite microspheres. The formation mechanism of the sea urchin-like microspheres has been clearly revealed. When removing the PS template with tetrahydrofuran, the sea urchin-like hollow PANI microspheres are obtained. This approach is simple and can produce these microspheres in bulk. The sea urchin-like PS/PANI composite microspheres display high BET surface areas and can be further used as catalyst supports.