Preparation of PSt/SiO₂nanoparticles with raspberry-like structure via nonionic surfactant miniemulsion polymerization

Preparation of inorganic/organic nanoparticles (NPs) with special morphology, controllable size, and good stability is important for widening their applications. In this study, a series of polystyrene (PSt)/SiO2 NPs with a raspberry-like structure was synthesized via a miniemulsion polymerization approach, using octaphenyl polyoxyethylene (CA-897) as a nonionic surfactant. To increase silica loading capacity, methacryloyloxyethyl trimethyl ammonium chloride (MTC) was introduced as an auxiliary monomer. The results indicate that the combinative employment of CA-897/SiO2 NPs/MTC could contribute to the formation of raspberry-like PSt/SiO2 nanohybrids with controlled size of 130–370 nm as well as adjustable silica inorganic content of 17–31 wt%, respectively. The raspberry structure played a significant role on the stabilization of PSt/SiO2 NPs in both electrolytic and strong basic/acidic environments.