Synthesis Of Ionic Liquid Modified Magnetic Janus Particles On A Microfluidic Chip

Janus particles have significant applications in emulsion stabilization,pannel display,drug delivery,biological sensing and many other fields,attributing to its unique structure and performance.The morphology and size of Janus particles are firmly related to its applications.Fabrication based on micro fluidics,which can accurately control the morphology and size of Janus particles,has drawn the most attention.The microfluidic chip-based preparation of Janus particles generally includes the formation of Janus droplets and solidification of particles.The preparation of Janus droplets is the critical step.The current ways for manipulating the morphology of Janus particles are limited and not flexible.In this thesis,the morphology of biphasic droplets was regulated by adding surfactants in three ways.The ionic liquid and Fe₃O₄ were introduced into the Janus droplets,and magnetic Janus particles modified by ionic liquid were prepared.In the first chapter,the preparation of functional particles based on micro fluidics,the Janus particles,the preparation methods of Janus particles,the functions and applications of Janus particles,and the applications and immobilization approaches of ionic liquid were reviewed.The advantages and disadvantages of various methods for preparating Janus particles,and immobilization methods of ionic liquid were summarized.In the end,the purpose and design of the thesis were proposed.In the second chapter,the Janus precursor droplets were prepared by using a micro fluidic chip with the flow-focusing structure,with the photopolymerized mixture of poly（ethylene glycol）diacylate and ionic liquid and ethoxylated trimethylolpropane triacrylate（ETPTA）as the dispersed phases and hexadecane as the continuous phase,respectively.Then,the droplets were solidified into Janus particles by UV-irradiation.The influences of three approaches to add surfactants in three phases separately,the concentration of surfactants and the flow velocity ratio of two dispersed phases on the morphology of the two-phase droplets were discussed in detail.The impact of the flow velocities of the continuous phase and the dispersed phase on droplet size was investigated.The magnetic Janus particles modified by ionic liquid was prepared through adding Fe₃O₄ nanoparticles to ETPTA.The major axis and minor axis of the particles are about 132 μm and 104 μm,respectively.Preliminary test results show that these particles possess favorable adsorption performance and rapid magnetic response.The preparation method is simple and fast,and the morphology of the droplets and particles can be flexibly manipulated.In the third chapter,the present work was summarized,and the potential application of as-prepared magnetic Janus particles modified by ionic liquid in adsorption and separation was prospected.