Poly(BMA-co-NVP)/NiS core-shell hybrid materials via Interfacial-initiated miniemulsion copolymerization and gamma-irradiation

In this work, N-butyl methacrylate (BMA)/N-vinyl-2-pyrrilidone (NVP) amphiphilic core-shell nanoparticles were successfully prepared via miniemulsion copolymerization, the emulsion was initiated by the redox initiation couple of cumene hydroperoxide (CHPO) and ferrous sulfate hydrate (FS). The synthetic waterborne polyurethane (WPU) was used as surfactant and hexadecane (HD) as co-stabilizer, respectively. FTIR and XPS were used to confirm the occurrence of copolymerization between two monomers. TEM and DLS were used to observe the particle morphology and determine the particle size and its polydispersity index (PDI). It was found that the core-shell poly(BMA-co-NVP) nanoparticles prepared via interfacial-initiated miniemulsion copolymerization (IMEP) had relatively small diameters (40–120 nm) and narrowly particle size distribution (0.066–0.243). Only about 2 wt% surfactants based on the solution was enough to prepare a stable miniemulsion. The results demonstrated that IMEP prompted the copolymerization of water-soluble NVP monomer with oil-soluble BMA monomer to form core-shell nanoparticles. The effects of surfactant and co-stabilizer affect on the miniemulsion copolymerization were discussed. All the results indicate that the fabrication amphiphilic core-shell nanoparticles via IMEP were successful. Then the poly(BMA-co-NVP)/NiS hybrid materials were fabricate via the reaction of NiSO₄ and CH₃CSNH₂ on the copolymers surface under ⁶⁰Co γ-irradiation at room temperature and ambient pressure. The hybrid materials were characterized by FESEM.