Preparation Of TiO₂ Nanoparticles And Its Electrophoretic Properties

Electronic ink is a panel display technology, which ultilizes electrophoretic movement of particles in the microcapsules to realize display. In this paper, experiment steps were predigested, sphericity white TiO₂ nanospheres were obtained via polymer latex templating procedure with Ti(OBu)4 as precursor, and calcinated at high temperature in air. To increase dispersibility and lipophilic degree, a better encapsulation was achieved by surface modification. Hollow or porous black TiO₂-C composite particles were obtained via polymer latex templating procedure with Ti(OBu)4 as precursor, and calcinated at high temperature in nitrogen.Titanium/polymer deposit particles were obtained using soap-free emulsion polymerization and tetra-n-butyl titanate deposition. The sphericity TiO₂ nanoparticles were made by sintering of deposit particles in air at 800℃by 3h, the size of the particles was about 350⁴50 nm, the zeta potential in tetrachloroethylene was 5.20 mV, the density of TiO₂ nanoparticles is 2.19 g/cm-3. The influences of reaction time, reactant and initiator'dosage and conditions on seed emulsion particles were investigated.Hollow TiO₂ nanoparticles prepared were used as raw materials; the hydrophobic KH570-TiO₂ particles were prepared by surface-modifying with a silane coupling agent, methacryloylpropyltrimethoxysilicane (KH570). Core-shell composite particles with modified-TiO₂ particles as core, the copolymer of styrene and divinylbenzene as shell were prepared by dispersion polymerization.The influences of different addition form of styrene and initiator dosage on TiO₂ / polymer core-shell composite particles were investigated. The results showed that diluted styrene were added in isobarically guttate filler, the effect was the best. The zeta potential of the core-shell composite particles in tetrachloroethylene was 3.10 mV, the density of TiO₂ nanoparticles is 1.68 g/cm-3.Hollow or porous black TiO₂-C composite particles were obtained. The XPS survey spectra of the composite indicated the presence of C, O, Ti ad N, and the mass ratio of TiO to TiO₂ is about 4:6. The results of XRD patterns indicated that the composite contained TiO to TiO₂, which validated the results of XPS. The composite nanoparticles were responding to the electric field (E = 5 0 V/mm), which showed that the composite particles had excellent electrophoretic properties.The morphology, ingredient and properties of particles were characterized by AFM, TEM, SEM, optical microscope, IR, TGA, XPS and micro electrophoretic apparatus.