Micron-sized porous magnetic microsphere and preparation method and application thereof

[0037] A preparation method of micron-scale porous magnetic microspheres, comprising the steps of:

[0038] Step 1, preparing seed microspheres by dispersion method; the specific method of preparing polymer microspheres by dispersion method in said step 1 is: dissolving the dispersant in alcohol, deoxygenating with nitrogen, stirring, heating, and then adding dissolved trigger The ethylene double bond-containing monomer of the agent is reacted for more than 6 hours, and cooled to room temperature after the reaction is completed. The particle size of the seed microspheres in the step 1 is 200nm-5um, preferably, the particle size is 1-2um. The polymerization system of the dispersion polymerization method is ethanol, acetonitrile, water, toluene, and methanol; specifically, the ethylene double bond monomer used in the first step of the seed microsphere is one of styrene, divinylbenzene, vinyl acetate, and acrylate Or both synthesized by emulsion polymerization.

[0039] Step 2, de

[0060] 1. Preparation of seed microspheres

[0061] Add 3.0g of dispersant PVP, 70g of ethanol and 30g of water into a 250ml four-necked glass reaction bottle, stir and pre-disperse in an oil bath at 68°C for 30min, and replace the air in the reactor with nitrogen; then add 0.5g of AIBN and 10g of monomer Styrene was formulated into a solution and injected into the reactor for reaction at 70°C for 24h. Cool to room temperature after the reaction, and set aside, the obtained seed microspheres are 1um.

[0062] 2. Fe 3 o 4 deposited on the surface of microspheres

[0063] Take 100ml of the seed microspheres, put them into a 2-liter four-necked flask, add 1000ml of deionized water into the four-necked reaction flask, and stir for 30 minutes. Weigh 6.1g FeCl3·6H2O and 3.8g FeCl2·4H2O into the stirred solution to dissolve. Pass high-purity nitrogen gas for 30 minutes to remove oxygen in the reaction system, add 20ml of 28% concentrated ammonia water dropwise, and react at 70°C fo