Preparation of Well-shaped Microcapsule Immobilizing Inorganic Nanoparticles*

A facile and efficient method has been developed for microencapsulation of metal oxide nanoparticles in polyurea via interfacial polymerization of toluene-2,4-diisocyanate and H2O through the atomizing emulsification approach. The resultant microcapsules were well-shaped and uniform sphere with diameter ranging from 2 to 6 μm. Thermogravimetry (TG) and differential scanning calorimetry (DSC) curves revealed that the microcapsules showed good thermal stability (no decomposition observed under 245°C). Besides, the microencapsulated TiO2 has been used as an efficient catalyst for photocatalytic degradation of methyl orange. Furthermore, the photocatalysis of immobilized TiO2 could be enhanced by introducing UV absorbing agent to the wall of microcapsules.