Preparation method of nano magnetic particles

[0024] See figure 1 , Is the process flow chart of the present invention, as shown in the figure, the method includes the following steps:

[0025] Step 1: Adsorb the hydrophobic substance on the magnetic particles to form hydrophobic strong magnetic particles;

[0026] Step 2: Perform the first emulsification, add surfactant, monomer solvent and initiator to the hydrophobic strong magnetic particles;

[0027] Step 3: The surfactant is adsorbed on the surface of the hydrophobic strong magnetic particles;

[0028] Step 4: Ultrasonic ultrasonic treatment;

[0029] Step 5: Form magnetic particles with uniform particle size in the core;

[0030] Step 6: Perform the second emulsification, add initiator and water, and heat to 90-110 。 C, the reaction time is 2-24h;

[0031] Step 7: Ultrasonic ultrasonic treatment and cleaning;

[0032] Step 8: Form magnetic particles with a uniform outer diameter of the polymer.

[0033] In this embodiment, the magnetic particles are one of ferric chloride, ferrous chloride, and iron oxide.

[0034] In this embodiment, the hydrophobic substance is an alkaline aqueous solution added with a strong adsorption substance.

[0035] In this embodiment, the strong adsorbent is one of fatty acid, fat, hydrophilic carboxyl group, and phosphorous group.

[0036] In this embodiment, the surfactant is a nonionic surfactant.

[0037] In this embodiment, the monomer solvent is one of a radical polymerization reaction monomer, styrene, acrylic acid, vinyl chloride, and acrylate.

[0038] In this embodiment, the initiator is one of potassium persulfate, ammonium persulfate, azobisisobutyronitrile, and azo polyethylene glycol.

[0039] The following is a specific embodiment of the method for preparing nano magnetic particles of the present invention:

[0040] 40nm magnetic particles are resolved in the aqueous solution, and the 200mg suspension is added with an aqueous sodium hydroxide solution of undecylenic acid. Undecylenic acid is adsorbed on the ferromagnetic particles to form hydrophobic magnetic particles. The hydrophobic ferromagnetic particles add non-ionic surface activity Agent, tirtonX-45 0.4g, treated with ultrasonic, non-ionic surfactant is adsorbed on the surface of hydrophobic particles to form a colloidal liquid. Add 0.1ml of the ionic surfactant n-undecylamine to the colloidal liquid to form a re-water There are non-ionic surfactants on the surface of gelatinous substances, and ionic activities coexist. In the polymerization reaction, styrene 3.0g, GMA 0.3g, AIBN 0.03g, DVB0.09g, and ethyl ether 2.5g were mixed into the gum to form a latex. Aging reaction, 70 degrees in KPS50mg, superposition reaction for 10 hours, washing three times to obtain iron oxide-coated polymer, through endoscopic observation, the average particle size is 163nm, the standard deviation is within 20nm, there are 1-4 titanium oxide in the core particle.