Synthesis of colloidal silica for production of polymer/silica nanocomposites by free living/controlled radical emulsion polymerization via RAFT technique

Abstract

Recently, the production of organic/inorganic hybrids through the incorporation of inorganic particles into a polymeric matrix by various polymerization techniques has received great attention, due to the many benefits provided to the final material. The contributions vary from costs reduction to improvements in the physical and optical properties of the composite compared to the pure polymer matrix. The emulsion and miniemulsion polymerizations are among the most feasible methods to achieve this goal. The main objective of this project is to study the use of a trithiocarbonilic macroRAFT agent comprising an ionizable block of acrylic acid (AA) and a block of poly(ethylene glycol) acrylate (PEGA) with random hydrophobic n-butyl acrylate (BA) units in the emulsion polymerization of methyl methacrylate (MMA) with n-butyl acrylate (BA) in the presence of silica particles. For this purpose, it is intended to initially synthesize the colloidal silica via enzymatic method, and then study the adsorption of the macroRAFT agent on the surface of the inorganic particle. Finally, we intend to use the complex macroRAFT/silica in the in situ emulsion copolymerization of MMA with BA. This project will be developed under the supervision of Prof. Dr. Amilton Martins dos Santos and is part of an ongoing project, Project IUPAC/FAPESP (2010/50383-5), coordinated by Prof. Dr. Amilton Martins dos Santos and developed in partnership with the groups of Dr. Elodie Bourgeat-Lami, from C2P2-CPE-CNRS in Lyon, France, and Dr. Ana Margarida Barros Timmons, from the University of Aveiro, in Portugal. (AU)