Self-assembly of polystyrene with pendant hydrophilic gold nanoparticles: the influence of the hydrophilicity of the hybrid polymers

Polystyrene (PS) with pendant hydrophilic gold nanoparticles (AuNPs) were synthesized by free radical copolymerization of styrene and AuNPs monomer at a liquid–liquid interface. The hybrid polymers can self-assemble into ordered structures in aqueous solutions. The hydrophilicity of the hybrid polymers plays a key role in the self-assembly of the polymers. A decrease in the number of hydrophilic AuNPs results in a transition from a micellar structure to a vesicular structure. After grafting of hydrophilic poly(N-vinyl pyrrolidone) chains to the pendant AuNPs, the self-assembly changes from a vesilcular structure to a core–shell-corona structure. The hybrid polymers and PS-coated Fe3O4 nanoparticles can self-assemble into vesicles with PS and PS-coated Fe3O4 nanoparticles in the walls and AuNPs in the coronae, and the size of the vesicles is determined by the number of pendant AuNPs.