Method for producing size-controllable magnetic hollow spheres

A hollow sphere and size technology, which is applied in the field of preparing size-controllable magnetic hollow spheres, can solve the problems of environmental pollution and high cost, and achieve the effects of broad application prospects, convenient operation, and simple steps

Inactive Publication Date: 2009-06-03
BEIJING UNIV OF CHEM TECH
View PDF1 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The above methods all introduce organic raw materials in the process of coating the template with magnetic particles or precursors, as precipitants, structure-directing agents or reaction media, so the synthesis process is costly and will pollute the environment

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] (1) Preparation of polystyrene template spheres with a size of 230 nm

[0028] At room temperature, add 1 g of polyvinylpyrrolidone, 220 mL of deionized water and 26 mL of styrene into the N 2 In the protected three-neck flask, under the stirring condition of 300 rpm, after stirring for 20 minutes, the temperature was raised to 70° C. in a water bath at a rate of 1° C. / min. Then, 20 mL of an aqueous potassium persulfate solution with a concentration of 30 g / L was dropped into the three-necked flask, and reacted at 70° C. for 24 hours. After the reaction solution was cooled to room temperature, it was centrifuged and washed twice with deionized water and ethanol to obtain polystyrene template spheres.

[0029] (2) Preparation of ferrite precursor-coated polystyrene spheres

[0030] At room temperature, ultrasonically disperse 80 mg of polystyrene template spheres in 50 mL of a mixed salt solution of cobalt nitrate and ferric chloride for 20 minutes, wherein the molar c...

Embodiment 2

[0035] (1) Preparation of polystyrene template spheres with a size of 560 nm

[0036] At room temperature, add 220 mL of deionized water and 26 mL of styrene to N 2 In the protected three-neck flask, under the stirring condition of 300 rpm, after stirring for 30 minutes, the temperature was raised to 70° C. in a water bath at a rate of 1° C. / min. Then, 20 mL of an aqueous potassium persulfate solution with a concentration of 30 g / L was dropped into the three-necked flask, and reacted at 70° C. for 20 hours. After the reaction solution was cooled to room temperature, it was centrifuged and washed twice with deionized water and ethanol to obtain polystyrene template spheres.

[0037] (2) Preparation of ferrite precursor-coated polystyrene spheres

[0038] At room temperature, ultrasonically disperse 80 mg template polystyrene spheres in 50 mL of a mixed salt solution of cobalt nitrate and ferric chloride for 20 minutes, wherein the molar concentration of divalent cobalt ions i...

Embodiment 3

[0043] (1) Preparation of polystyrene template spheres with a size of 560 nm

[0044] At room temperature, add 220 mL of deionized water and 26 mL of styrene to N 2 In the protected three-neck flask, under the stirring condition of 300 rpm, after stirring for 30 minutes, the temperature was raised to 70° C. in a water bath at a rate of 1° C. / min. Then, 20 mL of an aqueous potassium persulfate solution with a concentration of 30 g / L was dropped into the three-necked flask, and reacted at 70° C. for 20 hours. After the reaction solution was cooled to room temperature, it was centrifuged and washed twice with deionized water and ethanol to obtain polystyrene template spheres.

[0045] (2) Preparation of ferrite precursor-coated polystyrene spheres

[0046] At room temperature, ultrasonically disperse 80 mg template polystyrene spheres in 50 mL of a mixed salt solution of cobalt nitrate and ferric chloride for 20 minutes, wherein the molar concentration of divalent cobalt ions i...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
thicknessaaaaaaaaaa
diameteraaaaaaaaaa
Login to view more

Abstract

A method for producing size-controllable magnetic hollow spheres belongs to the technical field of magnetic materials. The method is characterized in that a monodisperse polystyrene sphere prepared by adopting the emulsion-polymerization method and dispersion-polymerization method is used as a template; inorganic metallic salts conduct coprecipitation under the action of a precipitating agent, namely sodium hydroxide, in a water solution; a ferrite precursor for coating the polystyrene sphere is formed by the deposition on the surface of the template sphere; and during the calcining process at the high-temperature, the ferrite precursor conducts the crystal transformation when the macromolecular spherical template decomposes, so that the polystyrene sphere coated with the ferrite precursor is converted into a corresponding magnetic hollow sphere. The method has the advantages of simple and convenient operation, favorable popularization and environmental friendliness. The magnetic hollow sphere prepared by adopting the method possesses a regulated and monodispersed hollow spherical structure and different magnetic properties, meets the requirement of different practical applications, and illustrates a good prospect of application in the fields, such as the separation science, the drug targeting preparation, the material science, the coating industry, and the like.

Description

technical field [0001] The invention belongs to the technical field of magnetic materials, and in particular provides a method for preparing magnetic hollow spheres with controllable size. technical background [0002] Magnetic materials with micro-nano structures have attracted the attention of researchers for many years due to their great application potential in ferrofluids, catalysts, dyes, high-density magnetic recording materials, and medical diagnosis. Among them, hollow spherical magnetic materials have the characteristics of low density, large specific surface area and good dispersion in liquid, and have great application prospects in the fields of separation science, drug targeting preparation, material science and coating industry. Thus, magnetic hollow spherical materials have attracted increasing research interest. [0003] The preparation methods of magnetic hollow spheres mainly include template-free one-time synthesis method and template removal method. In ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B01J13/02
Inventor 张慧侯荣盘登科段雪
Owner BEIJING UNIV OF CHEM TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap