Size And Structure Control Of Monodisperse Polystyrene Mesoporous Microspheres

In this paper,polystyrene mesoporous microspheres with controllable particle size distribution,specific surface area and pore size were prepared by dispersion polymerization and two-step swelling polymerization.The effects of the type of swelling agent,the ratio of the compound swelling agent and its dosage,and the concentration of the monomer on the morphology,particle size,specific surface area,and pore size of the mesoporous microspheres were explored.The mesoporous microspheres were characterized by laser particle size analyzer,scanning electron microscope(SEM)and specific surface area and pore size analyzer.Sulfonic acid-based mesoporous microspheres and silver nanoparticle composite microspheres were prepared by hydrophilic modification technology and in situ reduction method,respectively.And through the ultraviolet spectrophotometer to examine its ability to deal with dyes.The main research content is divided into the following three parts:(1)Using linear polystyrene microspheres prepared by dispersion polymerization as seed microspheres,polystyrene-divinylbenzene mesoporous microspheres were prepared by a two-step swelling polymerization method.The effects of the type of swelling agent,the ratio and amount of compound swelling agent and the concentration of monomer on the surface morphology,particle size and distribution,specific surface area and pore size of mesoporous microspheres were investigated.The results showed that the closer the solubility parameters of the swelling agent and the seed microspheres were,the better the swelling effect would be.When the ratio of dibutyl phthalate(DBP)to toluene was 2/1 and the dosage was 12g,the specific surface area and pore diameter of mesoporous microspheres reached the maximum,which were 261.97m~2/g and 8.29nm,respectively.The higher the monomer concentration,the larger the specific surface area and the smaller the pore size of the mesoporous microspheres.(2)Using polystyrene-divinylbenzene mesoporous microspheres as templates,sulfonic acid-based polystyrene mesoporous microspheres were obtained by hydrophilic modification technology.Subsequently,methylene blue and methyl orange were used to simulate dye wastewater,and the effects of different ionic dyes,sulfonation degree,pore size distribution,contact time and p H on the dye adsorption properties of mesoporous microspheres were studied.The effect of mesoporous structure on adsorption performance was elucidated.Finally,the sulfonic acid-based polystyrene mesoporous microspheres with the maximum adsorption capacity of 313.125 mg/g were prepared.(3)Using sulfonic acid-based polystyrene mesoporous microspheres as a template,silver ions were adsorbed and reduced in situ to prepare mesoporous microspheres loaded with silver nanoparticles.And the microspheres were subjected to adsorption and catalysis experiments.The experimental results showed that the mesoporous microspheres loaded with silver nanoparticles improved the processing ability of the composite microspheres to methylene blue and the recyclable reuse rate.