Preparation of PS/TiO2/UF multilayer core-shell hybrid microspheres with high stability.

In this paper, we report a facile method for preparation of polystyrene/titania/urea-formaldehyde resin (PS/TiO(2)/UF) multilayer core-shell hybrid microspheres with high stability through in situ condensation polymerization. The TEM images show that the thickness of UF shells is about 10 nm. The Zeta potential is close to zero. The density of PS/TiO(2)/UF could be controlled to 1.85 g/cm(3), which matches well with the non-polar dispersant (tetrachloroethylene). They are well dispersed and remain non-agglomerated even over several months, so they could be potential building blocks to fabricate electrophoretic display. Some parameters such as the ratio of urea-formaldehyde prepolymer (UFP) to PS/TiO(2), the pH value, and the temperature are also investigated.