Preparation Of New Janus Organic/inorganic Hybrid Composite Functional Particles

With the development of social production,environmental pollution is becoming more and more serious.Traditional environmental management materials are far from meeting the needs of environmental restoration,and new environmental management materials have emerged.Janus particles were a kind of composite nanoparticles with asymmetric structures and properties,which were newly developed in recent years.These particles have different physical or chemical properties on two sides,and have broad application prospects in the fields of environmental pollutant detection,environmental restoration and so on.Novel Janus particles with special structures and properties were still in the stage of exploration due to their small sizes,structures that were difficult to precisely control,complex preparation methods,and the lower yields.In this thesis,three kinds of novel Janus particles with special morphology and properties were synthesized by the combing of pickering emulsion method with other methods.These methods can not only flexibly control the sizes of Janus particles but also had a higher yield.The main contents were summarized as follows:1.First,using Pickering emulsion semi-protection method,a series of semi-raspberry Janus particles with large-size silica particles(400 nm,600 nm,1000 nm)as core and small-size silica nanoparticles(70 nm)as the single side crowns were synthesized by the asymmetric modification on the functional groups of the large-size silica particles.Among them,the sizes of semi-raspberry Janus particles could be adjusted by the sizes of large SiO2 particles.2.Second,semi-raspberry Janus particles with 600 nm silica nanoparticles as the core,70 nm silica nanoparticles on one side as crowns accompanying with double bonds on the other side were synthesized.The distillation-precipitation polymerization was carried out on the surface of semi-raspberry Janus particles with DVB as functional rigid monomer,AIBN as initiator and AA as functional monomer to initiate double bonds between Si0,particles with the small size.The thickness of PDVB layer was controlled at around 30～50 nm by controlling the polymerization conditions.The product was then etched with hydrofluoric acid(HF).Janus microcapsules with the large cavity in the middle and the pore structure on one side were synthesized.The microcapsules could be used as carriers for environmental restoration,and form rocket-like driving effects through unilateral channels.They have broad application prospects in the fields of environmental restoration.3.Finally,amphiphilic mushroom-shaped Janus particles with hydrophilic silica on one side and hydrophobic PDVB on the other side were synthesized by two methods in this thesis.The first method was to form amphiphilic mushroom-shaped Janus particles by asymmetrically modifying the two sides of the silica particles.The second method was to form amphiphilic mushroom-shaped Janus particles by modifying only one side of silica particles.The amphiphilic mushroom-shaped Janus particles formed by these two methods all have certain emulsifying properties and could be used as solid particle emulsifiers to emulsify incompatible two-phase liquids.