One-step synthetic route for conducting core-shell poly(styrene/pyrrole) nanoparticles

Conducting core-shell poly(styrene/pyrrole) (poly(St/Py)) particles were successfully prepared by a one-step solution route in soap-free emulsion polymerization. Hydrogen peroxide (H₂O₂) and a trace of ferric chloride (FeCl₃) were used as an initiator couple to carry out Fe -catalyzed oxidative polymerization. The average particle size of the particle was approximately 250 nm and its core-shell morphology (shell thickness ∼20-30 nm) was proved with transmission electron microscopy. The SEM images after CHCl₃ dissolution supported a clear evidence of distinct core-shell morphology, and which was confirmed by DSC and TGA analyses. We proposed a growth mechanism for the formation of the core-shell poly(St/Py) particles based on the time-evolution morphology of the particle. The result was also corroborated by the time-evolution GPC, FT-IR and ζ-potential data. The surface compositions of the particles were examined by X-ray photoelectron spectroscopy (XPS). The doped particles showed a high conductivity in the dry state.