Preparation And Application Of Micro/nano Porous Microspheres

Porous materials can be found in everywhere of nature world or modern city.The artificial porous materials are widely used in architecture,manned spaceflight,energy storage,adsorption and separation,and biomedicine field.Porous materials have gotten people's closely attention because of its special structure character,such as low density,high specific surface area,large porosity,and adsorption capacity.With the rapid change of social environment and the great enrichment of human material life,the demand for various porous materials in different circumstances increaseed continually.Compared with single structure porous materials,the functionally porous materials are more demanded by the world.Therefore,it is of very importance to design and prepare micro or nanoscale composite porous microspheres with hierarchical pore structure.In this work,three kinds of micro/nanoscale porous composite microspheres with different structures were prepared,and their applications in metal protection or dye adsorption were studied respectively.The main content of the research are as follows:1.Hollow mesoporous silica microspheres(HM-SiO2)with specific surface area of 674.0 m2/g were obtained by the condensation polymerization of alkoxysiIane on the surface of polystyrene microspheres in emulsion system and the removal of the template microspheres.HM-SiO2 microspheres were modified by 3-methacryloxypropyltrimethoxysilane,a silane coupling agent with double bond functional groups.Poly(dimethylamino-ethyl methacrylate)(PDMAEMA)polymer chains with pH responsive ability were grafted onto the surface of the microspheres by radiation technology.Then,HM-SiO2@PDMAEMA composite microspheres with average diameter of 275 nm were obtained.The corrosion inhibitor benzotriazole(BTA)was loaded into HM-SiO2@PDMAEMA composite microspheres by physical decompression technology.The composite microspheres exhibited different release behavior of BTA in acid/base environment and ideal anticorrosion performance for metal.2.Using sulfonated polystyrene microspheres as seed microspheres,cagelike polystyrene microspheres with specific surface area of 32.6 m2/g and a range of 60-80 nm pore size were prepared in specific water/alcohol system by organic solvent swelling.Then,pH responsive PDMAEMA and self-repairing poly(5-acetylamino pentyl acrylate)(PAAPA)were grafted onto the surface of the microspheres to endow cagelike polystyrene/polymer composite microspheres with self-repairing property.The composite microspheres exhibited environmental responsive ability at different pH.In addition,the microspheres can be self-repaired well after being scratched.3.Construct specific mixture solvent of alcohol,water,and other organic solvent for preparing fibrous silica microspheres based on polystyrene microspheres as templates.With the catalysis of alkali and dissolution performance of organic solvents,silica shell with fibrous structure were formed on the surface of modified polystyrene template microspheres,and the template microspheres were etched out at the same time.Therefore,fibrous hollow silica microspheres with suprehigh specific surface area(704.4 m2/g)and homogeneous particle size(?10nm)were obtained in one step method.The adsorption properties of the microspheres for different dyes were studied.It was found that fibrous hollow silica microspheres had high adsorption capacity for rhodamine B dye(250 mg/g).