Response surface optimization of miniemulsion: application to UV synthesis of hexyl acrylate nanoparticles

Abstract

This paper presents the UV synthesis in miniemulsion of nanoparticles from hexyl acrylate monomers using radical photoinitiator type I benzoin methyl ether. The optimization of such a miniemulsion composition is studied to produce monodisperse nanoparticles with a mean size d p inferior to 200 nm after photopolymerization of the droplets. The correlation between the size distributions of the droplets and the corresponding nanoparticles was verified. Therefore, a composite design was built as regards to the amount of the surfactant (sodium dodecyl sulfate), the co-stabilizer (pentadecane), and the monomer (hexyl acrylate) in order to model the mean size and the polydispersity of the miniemulsion droplets. A range of monodisperse droplets size between 150 and 175 nm was achieved. After UV irradiation, high monomer conversion yield (>90 %) was reached leading to nanoparticles with mean size ranging from 100 to 165 nm. These hexyl acrylate nanoparticles have been obtained after 10 min of irradiation, offering new opportunities for nanoparticles synthesis in enclosed and/or plastic vessels.