Preparation And Modification Of The Janus Microspheres Of Titanium Compounds-Styrene Based Polymer

Janus particles are fabricated by two parts with different morphology or surface chemical properties. Janus particles with special physical and chemical performance haves diversified potential applications in self-assembly, functional surfactants and biosensor and so on. Therefore, it is of great theoretical and realistic significance to synthesize novel morphology and anisotropic Janus material. To date, there are many kinds of reported methods for preparing Janus particles. Among these, the method of emulsion swelling assisted protrusion arouses extensive interest of researchers because of its batch production and controllable morphology.In this research, the monodisperse polystyrene microspheres were produced by seed-emulsion polymerization. Firstly, the polystyrene microspheres were sulfonated by concentrated sulfuric acid. Then the core-shell composite particles of PS@TiO2, PS@UFe and PS@UTi were prepared using the sol-gel method. Thirdly, the Janus particles of Ti02-poly (VBC-DVB), UFe-PS and UTi-PS were obtained by emulsion swelling assisted protrusion. Finally, the Janus particles were modified and the functional Janus particles of TiO2-Ag, TiO2-QApoly (VBC-DVB) and UTi-PANi were obtained. The morphology and chemical structure of the Janus materials were characterized by SEM, TEM, FT-IR, EDX, XPS, TG, XRD, UV and elemental analysis, etc.The results showed that the core-shell composite particles with a certain thickness of" the shell can be used for preparing Janus particles by emulsion swelling assisted protrusion. The target product of TiO2-Ag Janus composite particles was synthesized and the silver nanoparticles deposited on the surface of the lobe of poly (VBA-DVB) were about30nm. The final number and fraction of Ag particles could be tuned by changing Tollens’reaction time. The Janus composite particles of TiO2-Ag can be expected to exploit as directional catalysis agent. The quaternaty ammonium groups endowed the Janus composite particles of TiO2-QApoly (VBC-DVB) higher initial thermal decomposition temperature than that of TiO2-poly (VBC-DVB). The product was expected to be used as phase transfer catalysts, which was confirmed by the esterification reaction of benzyl chloride and sodium acetate to benzyl acetate. The yield of benzyl acetate reached87.6%in the presence of the phase transfer catalyst of TiO2-QApoly (VBC-DVB). Additionly, the classical synthetic polymer part was replaced with UFe and UTi in the Janus particles of UFe-PS and UTi-PS. This kind of Janus particles possesses the excellent properties of law lacquer and it can be modified further attributing to the benzene ring, phenol hydroxyl and unsaturated side chain of urushiol.