CN112723418A

CN112723418A - Method for simply and conveniently preparing large amount of monodisperse magnetic nanoparticles

Info

Publication number: CN112723418A
Application number: CN202011241922.3A
Authority: CN
Inventors: 刘江帅; 汤颖珍; 傅勇军
Original assignee: Jinhua Nuoke Biotechnology Co ltd
Current assignee: Jinhua Nuoke Biotechnology Co ltd
Priority date: 2020-11-09
Filing date: 2020-11-09
Publication date: 2021-04-30

Abstract

The invention relates to a method for simply and conveniently preparing a large number of monodisperse magnetic nanoparticles, which comprises the following steps: step 1, carrying out reflux reaction on sodium oleate and ferric chloride hexahydrate in a mixed solvent of absolute ethyl alcohol, deionized water and normal hexane to prepare an iron oleate complex; step 2, taking water as a solvent, and extracting and purifying the iron oleate complex for multiple times; step 3, dissolving the purified waxy iron oleate complex and oleic acid in a 1-octadecene solvent, performing pyrolysis, then precipitating with ethanol, and performing centrifugation and drying to obtain monodisperse magnetic nanoparticles; the simple and convenient method for preparing the monodisperse magnetic nanoparticles in large quantity, provided by the invention, has the advantages that the reaction conditions are convenient to control, the product is simple and convenient to separate and purify, the magnetic nanoparticles can be simply and conveniently prepared in large quantity, the sizes of the magnetic nanoparticles can be regulated and controlled through the concentration of oleic acid and the boiling point of a reaction solvent, and the magnetic nanoparticles with different sizes can be conveniently prepared.

Description

Method for simply and conveniently preparing large amount of monodisperse magnetic nanoparticles

Technical Field

The invention relates to the technical field of magnetic nano materials, in particular to a method for simply and conveniently preparing a large amount of monodisperse magnetic nano particles.

Background

The application of the magnetic nano material can be said to relate to various fields, have extensive application prospects in the fields of machinery, electronics, optics, magnetism, chemistry, biology and the like, the birth of the nano scientific technology can generate profound influence on the human society, and can possibly fundamentally solve many problems faced by human beings, in particular important problems of energy, human health, environmental protection and the like, the main task of the next century is to design various novel materials and devices conforming to the century according to various novel physical and chemical characteristics of the nano material, the novel product of the high-tech content and the development nano structure of the traditional product is improved by modifying the nano material scientific technology, the novel product becomes the basis of the economic and new point of the next century, the magnetic nano material becomes a great bright star in the nano material scientific field, and the magnetic nano material can be a great splendid star in the fields of new materials, energy and energy, energy and biology and the like, Information, biomedicine, and the like play important roles.

The magnetic nano materials are more in variety, the most widely applied iron oxide is currently used, the existing preparation methods of the iron oxide magnetic nano particles comprise a precipitation method, an impinging stream method, a reverse microemulsion method, a sol-gel method, a polyol method and the like, the reaction conditions of the methods are difficult to control, the separation and purification of products are complex, the large-scale preparation cannot be simply and conveniently carried out, and the size of the nano particles is regulated and controlled by adjusting experimental conditions.

Disclosure of Invention

Technical problem to be solved

The invention aims to provide a method for simply, conveniently and massively preparing monodisperse magnetic nanoparticles, and aims to solve the problems that in the prior art, the preparation method of the iron oxide magnetic nanoparticles comprises a precipitation method, an impinging stream method, a reverse microemulsion method, a sol-gel method, a polyol method and the like, the reaction conditions of the methods are difficult to control, the separation and purification of products are complex, the massive preparation cannot be simply and conveniently carried out, and the size of the nanoparticles is regulated and controlled by adjusting experimental conditions.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: a method for simply preparing a large amount of monodisperse magnetic nanoparticles comprises the following steps:

step (1), preparation of iron oleate complex: weighing 120mmol of sodium oleate and putting into a 500ml three-necked bottle, weighing 40mmol of ferric chloride hexahydrate and adding into the three-necked bottle, weighing 280ml of reaction solvent and pouring into the three-necked bottle, then building a condensation reflux device, heating to 70 ℃ under the protection of nitrogen, keeping constant temperature and carrying out reflux reaction for 4 hours, standing for a period of time after the reaction is finished, and collecting an upper layer solution to obtain an iron oleate complex mixed solution;

step (2), purifying an iron oleate complex: pouring the mixed solution of the iron oleate complex obtained in the step (1) into a separating funnel in batches, pouring 50ml of deionized water into each batch, adding the deionized water into an extraction bottle, repeatedly oscillating, standing for layering, collecting supernatant, repeatedly extracting for 3 times, collecting the supernatants of all batches, performing rotary evaporation, removing n-hexane, and drying in a vacuum drying box to obtain a waxy iron oleate complex;

step (3), preparing monodisperse magnetic nanoparticles: weighing 40mmol of the waxy iron oleate complex obtained in the step, measuring 20mmol of oleic acid, adding the waxy iron oleate complex into a three-necked bottle, adding a reaction solvent, mixing to dissolve the waxy iron oleate complex, placing the waxy iron oleate complex into an oil bath kettle, building a condensation reflux reaction device, slowly heating to 320 ℃ at a constant heating rate, keeping constant temperature for reflux reaction for 30min, cooling to room temperature after the reaction is finished, pouring the mixed solution into a 1000ml beaker, measuring 500ml of ethanol, adding the ethanol into the beaker for precipitation, and centrifuging to obtain the monodisperse magnetic nanoparticles. .

Preferably, in the step (1), the reaction solvent is a mixed solution of absolute ethyl alcohol, deionized water and n-hexane.

Preferably, in the step (1), the mixing ratio of the absolute ethyl alcohol, the deionized water and the normal hexane in the reaction solvent is 4:3: 7.

Preferably, in the step (3), the reaction solvent is one of 1-hexadecene, dioctyl ether, 1-octadecene, 1-eicosene and trioctylamine, and the addition amount of the reaction solvent is 0.79 mol.

Preferably, in the step (3), the reaction solvent is 1-octadecene.

Preferably, in the step (3), the temperature is slowly increased to 320 ℃ at a constant temperature increase rate of 3.3 ℃/min during the reaction.

(III) advantageous effects

The invention provides a simple and convenient method for preparing a large number of monodisperse magnetic nanoparticles, which is characterized in that sodium oleate and ferric chloride hexahydrate are used for preparing an iron oleate complex, then water is used for extracting the iron oleate complex for a plurality of times to obtain a waxy iron oleate complex, the waxy iron oleate complex and oleic acid are dissolved in a 1-octadecene solvent for high-temperature decomposition, then ethanol is used for precipitation, and centrifugation and drying are carried out to obtain the monodisperse magnetic nanoparticles.

Drawings

Figure 1 is a reaction scheme for the preparation of iron oleate complexes from sodium oleate and ferric chloride hexahydrate.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Examples

A method for simply preparing a large amount of monodisperse magnetic nanoparticles comprises the following steps:

step (1), preparation of iron oleate complex: weighing 120mmol of sodium oleate, putting the sodium oleate into a 500ml three-necked bottle, weighing 40mmol of ferric chloride hexahydrate, adding the ferric chloride hexahydrate into the three-necked bottle, then respectively weighing 80ml of absolute ethyl alcohol, 60ml of deionized water and 140ml of n-hexane by using a measuring cylinder, adding the absolute ethyl alcohol, 60ml of deionized water and 140ml of n-hexane into the three-necked bottle to serve as reaction solvents, then building a condensation reflux device, heating to 70 ℃ under the protection of nitrogen, keeping constant-temperature reflux reaction for 4 hours, standing for a period of time after the reaction is finished, collecting an upper-layer solution, and obtaining an iron oleate complex mixed solution;

wherein the reaction route of the iron oleate complex is shown in figure 1

step (3), preparing monodisperse magnetic nanoparticles: weighing 40mmol of the waxy iron oleate complex obtained in the step, weighing 20mmol of oleic acid, adding into a three-necked bottle, weighing 0.79mol of 1-octadecene, adding into the three-necked bottle, mixing, dissolving the iron oleate complex, placing in an oil bath pot, building a condensation reflux reaction device, slowly heating to 320 ℃ at a constant heating rate of 3.3 ℃/min, keeping a constant temperature reaction for 30min, cooling to room temperature after the reaction is finished, pouring the mixed solution into a 1000ml beaker, weighing 500ml of ethanol, adding into the beaker, precipitating, centrifuging, and drying the obtained product in a drying box to obtain the monodisperse magnetic nanoparticles.

Wherein, the influence of the boiling point of the reaction solvent in the step (3) on the size of the monodisperse magnetic nanoparticles was studied, and the results are shown in table 1:

TABLE 1 Effect of solvent boiling on magnetic nanoparticle size

As can be seen from table 1, the sizes of the magnetic nanoparticles are different at different boiling points of the solvent, and the sizes of the magnetic nanoparticles gradually increase with the increase of the boiling point of the solvent, and in addition, the influence of the concentration of oleic acid on the sizes of the magnetic nanoparticles is also studied, and the increase of the concentration of oleic acid and the increase of the sizes of the magnetic nanoparticles are found, so that the sizes of the magnetic nanoparticles can be adjusted and controlled by adjusting the reaction conditions.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A method for simply preparing a large amount of monodisperse magnetic nanoparticles is characterized by comprising the following steps:

step (3), preparing monodisperse magnetic nanoparticles: weighing 40mmol of the waxy iron oleate complex obtained in the step, measuring 20mmol of oleic acid, adding the waxy iron oleate complex into a three-necked bottle, adding a reaction solvent, mixing to dissolve the waxy iron oleate complex, placing the waxy iron oleate complex into an oil bath kettle, building a condensation reflux reaction device, slowly heating to 320 ℃ at a constant heating rate, keeping constant temperature for reflux reaction for 30min, cooling to room temperature after the reaction is finished, pouring the mixed solution into a 1000ml beaker, measuring 500ml of ethanol, adding the ethanol into the beaker for precipitation, and centrifuging to obtain the monodisperse magnetic nanoparticles.

2. The method of claim 1, wherein the method comprises the following steps: in the step (1), the reaction solvent is a mixed solution of absolute ethyl alcohol, deionized water and normal hexane.

3. A simple method for the mass production of monodisperse magnetic nanoparticles according to claim 1 or 2, characterized in that: in the step (1), the mixing ratio of the absolute ethyl alcohol, the deionized water and the normal hexane in the reaction solvent is 4:3: 7.

4. The method of claim 1, wherein the method comprises the following steps: in the step (3), the reaction solvent is one of 1-hexadecene, dioctyl ether, 1-octadecene, 1-eicosene and trioctylamine, and the addition amount of the reaction solvent is 0.79 mol.

5. A simple method for preparing a large amount of monodisperse magnetic nanoparticles according to claim 1 or 4, wherein: in the step (3), the reaction solvent is 1-octadecene.

6. The method of claim 1, wherein the method comprises the following steps: in the step (3), the temperature is slowly increased to 320 ℃ at a constant temperature increase rate of 3.3 ℃/min in the reaction process.