Zirconium oxocluster/polymer hybrid nanoparticles prepared by photoactivated miniemulsion copolymerization

The photoactivated free radical miniemulsion copolymerization of methyl methacrylate (MMA) and the zirconium oxocluster Zr₄O₂(methacrylate)₁₂ is used as an effective and fast preparation method for polymer/inorganic hybrid nanoparticles. The oxoclusters, covalently anchored to the polymer network, act as metal-organic cross-linkers, thus improving the thermomechanical properties of the resulting hybrid nanoparticles. Benzoin carbonyl organic compounds were used as photoinitiators. The obtained materials are compared in terms of cross-linking, effectiveness of cluster incorporation, and size distribution with the analogous nanoparticles produced by using conventional thermally induced free radical miniemulsion copolymerization. The kinetics of the polymerization process in the absence and in the presence of the oxocluster is also investigated.