Atom transfer radical polymerization of n-butyl acrylate from silica nanoparticles

This article reports the synthesis of atom transfer radical polymerization (ATRP) of active initiators from well-defined silica nanoparticles and the use of these ATRP initiators in the grafting of poly(n-butyl acrylate) from the silica particle surface. ATRP does not require difficult synthetic con ditions, and the process can be carried out in standard solvents in which t he nanoparticles are suspended. This "grafting from" method ensures the cov alent binding of all polymer chains to the nanoparticles because polymeriza tion is initiated from moieties previously bound to the surface. Model reac tions were first carried out to account for possible polymerization in dilu ted conditions as it was required to ensure the suspension stability. The u se of n-butyl acrylate as the monomer permits one to obtain nanocomposites with a hard core and a soft shell where film formation is facilitated. Char acterization of the polymer-grafted silica was done from NMR and Fourier tr ansform infrared spectroscopies, dynamic light scattering, and DSC. (C) 200 1 John Wiley & Sons, Inc.