Immobilization of Xanthate Agent on Titanium Dioxide and Surface Initiated RAFT Polymerization.

Surface modification of titanium dioxide (TiO2) nanoparticle is essential to control its surface properties, thereby to enhance its cell penetration capability, reduce its cytotoxicity, or improve its biocompatibility. In order to graft polyvinyl acetate onto TiO2 nanoparticles, xanthate was chemically immobilized on the surface of TiO2 by acylation followed by nucleophilic substitution with a carbodithioate salt. Reversible addition fragmentation chain transfer polymerization was conducted to graft vinyl acetate onto the surface of TiO2. Both the TiO2-xanthate and TiO2-polyvinyl acetate hybrids were characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The chemical immobilization of xanthate on the surface of TiO2 and the subsequent controlled polymerization provide useful insight for decoration and modification of TiO2 and other nanoparticles.