Size And Structure Control Of Monodisperse Microsize Polystyrene Microspheres And Their Application

Monodisperse polystyrene microspheres is one of important carriers of supported catalyst material.In this study,monodisperse polystyrene microspheres were constructed by dispersion polymerization,and then mesoporous polystyrene microspheres were constructed by two-step swelling polymerization.The catalytic performance of mesoporous polystyrene microspheres loaded with Fe₃O₄and silver were studied in detailed.This manuscript is divided into the following three parts:In the first part,the effects of the content of stabilizer,the composition of continuous phases,the proportion of comonomer and the amount of chain transfer agent on the particle size and molecular weight of polystyrene microspheres were studied.The experimental results showed that the particle size of polystyrene microspheres prepared by dispersion polymerization system decreased with the increase of stabilizer dosage or polarity of continuous phase,and increase with the increase of chain transfer dosage.The addition of1,1-diphenylethylene could reduce the dispersion polymerization rate,widen the particle size distribution and reduced the average molecular weight of styrene.By optimizing the proportion of each component in dispersion polymerization,the particle size of 3?m monodisperse polystyrene microspheres.In the second part,the monodisperse polystyrene microspheres with mesoporous structure were constructed by the two-step swelling polymerization using monodisperse polystyrene seed microspheres prepared as template.The effects of the type and content of swelling agent,initiator,monomer and crosslinking agent on the pore size and distribution of mesoporous microspheres were systematically studied.The factors affecting the pore size distribution of the final mesoporous microspheres were determined.The mechanism and process of mesoporous structure construction in the swelling polymerization process were elucidated.Finally,the mesoporous microspheres with the size of 7?m with mesoporous structure were obtained.In the third part,the magnetic polystyrene microspheres were prepared by in-situ oxidation with ferrous ion adsorbed in vacuum.The surface of the microspheres was coated and functionalized by grafting polymerization of MMA in order to prepare the magnetic polystyrene microspheres with carboxyl groups on the surface.Finaly the magnetic polystyrene microspheres were loaded with elemental silver for catalytic reaction.The results showed that the magnetic microspheres loaded with silver have a good catalytic effect on Rh6G.In addition,easily separated from the productions.In this paper,the preparation methods of polymer magnetic spheres loaded with silver were systematically described,and the control methods of the size and structure of polymer microspheres were discussed,which is of great significance for the construction of mesoporous materials and the preparation of catalyst support.