Preparation and characterization of TiO2-cationic hybrid nanoparticles as electrophoretic particles

Abstract The hybrid nanoparticles (TiO 2 -HNPs) with TiO 2 nanoparticles as core and with poly( N , N -dimethylaminoethyl methacrylate- co -methyl methacrylate) by using triallylamine as cross-linking agent as shell were firstly prepared via atom transfer radical polymerization (ATRP) in methanol. Then the hybrid nanoparticles with positive charge were produced by the quaternization with methyl iodide as quaternization reagent so as to endow them with greater electrophoretic mobility. The cationic hybrid nanoparticles (TiO 2 -CHNPs) were studied by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy and dynamic light scattering (DLS) measurements. The results indicate that the cationic polymer is successfully grafted on the surface of the TiO 2 nanoparticles. The particle size of TiO 2 -CHNPs is about 150 nm and the polydispersity index (PDI) is 0.307. The zeta potential, the contrast ratio of white state to dark state and response time of TiO 2 -CHNPs are +16.8 mV, 30 and 3 s, respectively, which show the potential application prospect in the development of electrophoretic ink.