The Design And Reserch Of Complex Microparticles And Their Application In The Fabraction Of Nuclear Fuel Microspheres

Polymer microparticles have been long used in the development of mankind history and play a more and more important role in modern society. Traditional heterogeneous polymerization process (suspension, emulsion, dispersion, seed) can not meet the demand of synthesis of complicated and various functional polymer microparticles. Microfluidics has attracted widely attention both here and abroad as a new way to prepare polymer microparticles. It is a technology that control and handle microdroplets via microchannels or capillaries in the size of tens to hundreds microns, fabricating monodisperse droplets with size, component and shape been accurately designed.The technology of microfluidic-assisted synthesis of polymer particles has matured after almost ten years of development. Research achievements about the design and manufacture of microfluidic devices, the formation mechanism of droplets and the control of the droplets size and so on have been abtained. At the same time, it has been videly studied about the synthesis of compliceted droplets and particles in microfluidics. Core-shell droplets, Janus droplets, multiple emulsions and multi-component double emulsions have been produced with their size and morphology been controlled.Our lab has years of technology accumulation in the field of microfluidics, and has deeply explored the synthesis of complex droplets with microfluidic. On the basis of previous studies, this graduation thesis focus on the researches as follow:(1) formation of biphasic Janus droplets in the capillary-based microfluidic device, exploring the relation between its architectural feature and preparation parameters and summing up a empirical equation describing this relation. This equation not only guide the synthesis of Janus droplets, but also reveal the laws of droplets structural transformation;(2) the preparation of Janus core-shell particles which have not been abtained before. Janus core-shell particle integrates the structure of Janus particle as well as core-shell particle, which will be be applied in some potential areas such as direct drug delivering. This graduation not only prepare Janus core-shell particles succesfully, but also study how to control their morphology and number of cores;(3)prepeartion of simulation nuclear fuel microsphere CeO2by the method for the preparation of Janus core-shell droplets at room temperature, overcoming the shortcoming of conventional method that have to be conducted at low temperature; (4); make a tentative study on the synthesis of essence microparticles with microfluidic and study their internal structure and release rate of essence;(5) make a discussion and review on recent trends and development direction in the future of microfluidic.