阅读说明：本技术 一种磁性塑料及其制备方法 (Magnetic plastic and preparation method thereof ) 是由 陈宇 于 2021-08-16 设计创作，主要内容包括：本申请涉及高分子材料的技术领域,具体公开了一种磁性塑料及其制备方法。一种磁性塑料,由包含以下重量份的原料制成：低密度聚乙烯40-50份、硅藻土1-1份、氮化硼1-3份、粘胶纤维1-3份、聚乳酸40-60份、磁性体10-20份,所述磁性体包括纳米磁粉和分散材料,所述分散材料包括十二烷基硫酸钠；其制备方法为：S1、一次混合；S2、二次混合；S3、挤出成型。本申请的磁性塑料能够提高磁粉在磁性塑料中的分散性,进而提高磁性塑料的磁性。另外,本申请的磁性塑料的制备方法操作简单、应用广泛。(The application relates to the technical field of high polymer materials, and particularly discloses a magnetic plastic and a preparation method thereof. The magnetic plastic is prepared from the following raw materials in parts by weight: 40-50 parts of low-density polyethylene, 1-1 part of diatomite, 1-3 parts of boron nitride, 1-3 parts of viscose fiber, 40-60 parts of polylactic acid and 10-20 parts of magnetic body, wherein the magnetic body comprises nano magnetic powder and a dispersion material, and the dispersion material comprises sodium dodecyl sulfate; the preparation method comprises the following steps: s1, primary mixing; s2, secondary mixing; and S3, extrusion molding. The magnetic plastic can improve the dispersibility of magnetic powder in the magnetic plastic, and further improves the magnetism of the magnetic plastic. In addition, the preparation method of the magnetic plastic is simple to operate and wide in application.)

1. The magnetic plastic is characterized by being prepared from the following raw materials in parts by weight:

40-50 parts of low-density polyethylene;

1-1 part of diatomite;

1-3 parts of boron nitride;

1-3 parts of viscose;

40-60 parts of polylactic acid;

10-20 parts of a magnetic body, wherein the magnetic body comprises nano magnetic powder and a dispersion material, and the dispersion material comprises sodium dodecyl sulfate.

2. A magnetic plastic according to claim 1, wherein: the nano magnetic powder comprises nano barium ferrite and a surfactant, the surfactant is coated outside the nano barium ferrite to form a nano magnetic powder microsphere with a core-shell structure, and the nano magnetic powder microsphere with the core-shell structure is prepared by the following method:

(1) preparation of a soot-like powder: mixing 1-3 parts by weight of barium carbonate, 8-12 parts by weight of ferric nitrate nonahydrate, 9-15 parts by weight of citric acid and 10-20 parts by weight of water, stirring for 10-16h, adjusting the pH value to 5-9, and evaporating and combusting to obtain soot-like powder;

(2) and (3) calcining: grinding the soot-like powder in the step (1) and then calcining to obtain nano barium ferrite;

(3) coating: and (3) mixing the surfactant and the nano barium ferrite in the step (2) according to the mass ratio of (4-8): (8-12) stirring after mixing to obtain the nano magnetic powder microspheres with the core-shell structure.

3. A magnetic plastic according to claim 2, wherein: the temperature of the calcination treatment in the step (2) is 850-950 ℃.

4. A magnetic plastic according to claim 2, wherein: the particle size of the nano barium ferrite is 10-15 nanometers.

5. A magnetic plastic according to claim 2, wherein: the surfactant comprises any one of sodium oleate, Tween 80 and PEG surfactant.

6. A magnetic plastic according to claim 5, wherein: the surfactant comprises a PEG surfactant, and the PEG surfactant is PEG 4000.

7. A magnetic plastic according to claim 1, wherein: the magnetic body is prepared by the following method: according to the weight portion, 1-3 portions of nano magnetic powder, 2-4 portions of absolute ethyl alcohol, 3-5 portions of agate balls and 2-4 portions of dispersing material are put into a ball mill according to the mass ratio, and are ball milled for 10-20 hours at the rotating speed of 400 plus materials 600r/min, so as to obtain the magnetic body.

8. The method for preparing a magnetic plastic according to any one of claims 1 to 7, comprising the following steps:

s1, primary mixing: according to the formula, mixing and stirring the diatomite, the boron nitride and the viscose fiber to obtain a mixture;

s2, secondary mixing: sequentially adding the low-density polyethylene, the polylactic acid, the magnetic body and the mixture into a temperature-controlled high-speed mixer, and mixing and stirring to obtain a mixed material;

s3, extrusion molding: and adding the mixed materials into a double-screw extruder, melting, extruding and naturally airing to obtain the magnetic plastic.

Technical Field

The application relates to the technical field of high polymer materials, in particular to a magnetic plastic and a preparation method thereof.

Background

The magnetic plastic is a plastic product with magnetism, common plastic has no ferromagnetism, but the ferromagnetic plastic can be formed by a special method: one approach, which has been sought to alter the composition of plastics so that they are magnetic, is under investigation. Secondly, magnetic powder is added into common plastic to form composite magnetic plastic, and the magnetic plastic manufactured by the method is widely applied in our lives.

The composite magnetic plastic is mainly composed of resin and magnetic powder, wherein the resin plays a role in bonding, and the magnetic powder is a magnetic source. The magnetic powder used for filling is mainly ferrite magnetic powder and rare earth permanent magnetic powder. The composite magnetic plastics can be divided into two categories according to the magnetic characteristics: one is that the easy magnetization direction of the magnetic particles is arranged disorderly, called isotropic magnetic plastic, which has lower performance. The other type is that the easy magnetization directions of the magnetic powder are arranged in sequence by an external magnetic field or mechanical force in the processing process, and the magnetic powder is called anisotropic magnetic plastic.

The magnetic nanometer polymer material has wide application prospect and is commonly used for preparing magnetic plastics in magnetic powder. However, the nano particles are easy to agglomerate due to small particle size, so that the magnetic powder is not easy to be uniformly dispersed in the rest components of the magnetic plastic, and the magnetism of the magnetic plastic needs to be improved.

Disclosure of Invention

In order to improve the dispersibility of magnetic powder in magnetic plastics and further improve the magnetism of the magnetic plastics, the application provides the magnetic plastics and a preparation method thereof.

In a first aspect, the present application provides a magnetic plastic, which adopts the following technical scheme:

the magnetic plastic is prepared from the following raw materials in parts by weight: 40-50 parts of low-density polyethylene, 1-1 part of diatomite, 1-3 parts of boron nitride, 1-3 parts of viscose fiber, 40-60 parts of polylactic acid and 10-20 parts of magnetic body, wherein the magnetic body comprises nano magnetic powder and a dispersion material, and the dispersion material comprises sodium dodecyl sulfate.

By adopting the technical scheme, the magnetic body is added into the magnetic plastic, and the magnetic body comprises the nanometer magnetic powder and the dispersed material, so that the nanometer magnetic powder has larger magnetism compared with the common magnetic powder. Meanwhile, the addition of the sodium dodecyl sulfate is combined with the nano magnetic powder to improve the dispersibility of the nano magnetic powder, so that the uniform dispersion of the nano magnetic powder in the magnetic plastic is improved, and the magnetism of the magnetic plastic is further improved.

Preferably, the nano magnetic powder comprises nano barium ferrite and a surfactant, the surfactant is coated outside the nano barium ferrite to form a nano magnetic powder microsphere with a core-shell structure, and the nano magnetic powder microsphere with the core-shell structure is prepared by the following method:

(1) preparation of a soot-like powder: mixing 1-3 parts by weight of barium carbonate, 8-12 parts by weight of ferric nitrate nonahydrate, 9-15 parts by weight of citric acid and 10-20 parts by weight of water, stirring for 10-16h, adjusting the pH value to 5-9, and evaporating and combusting to obtain soot-like powder;

(2) and (3) calcining: grinding the soot-like powder in the step (1) and then calcining to obtain nano barium ferrite;

(3) coating: and (3) mixing the surfactant and the nano barium ferrite in the step (2) according to the mass ratio of (4-8): (8-12) stirring after mixing to obtain the nano magnetic powder microspheres with the core-shell structure.

By adopting the technical scheme, the nano barium ferrite is used for enabling the magnetic plastic to have magnetism, and the surfactant is used for carrying out surface modification on the nano barium ferrite, so that the nano barium ferrite, the dispersing material and the other components of the magnetic plastic are well combined, and the nano magnetic powder, namely the dispersibility of the nano barium ferrite in the magnetic plastic is further improved. The core-shell structure is used for enabling the surface active agent to be uniformly coated on the surface of the nano barium ferrite, so that the nano barium ferrite and the surface active agent have larger combination area, and the modification effect of the nano barium ferrite is improved. The microsphere structure makes the surface of the nanometer magnetic powder smooth, and increases the lubricity of the nanometer magnetic powder, thereby further improving the dispersibility of the nanometer magnetic powder and further improving the magnetism of the magnetic plastic.

Preferably, the temperature of the calcination treatment in the step (2) is 850-.

By adopting the technical scheme, the ash-shaped powder in the step (1) is calcined at the temperature to generate more pure nano barium ferrite, so that the magnetism of the nano barium ferrite is improved, and further the magnetism of the magnetic plastic is improved.

Preferably, the particle size of the nano barium ferrite is 10-15 nanometers.

By adopting the technical scheme, the nanometer barium ferrite with the grain diameter of 10-15 nanometers can improve the magnetism of the nanometer magnetic powder. The nano magnetic powder microspheres with the particle size of 1-10 microns are small in particle size, and can be conveniently dispersed in the magnetic plastic to form good combination with other components of the magnetic plastic after being combined with the dispersing material. Meanwhile, the nanometer magnetic powder microspheres with the particle size range enable the surfactant to have better coating thickness on the nanometer magnetic powder, and further improve the dispersibility of the nanometer magnetic powder microspheres, so that the magnetism of the magnetic plastic is further improved.

Preferably, the surfactant comprises any one of sodium oleate, tween 80 and PEG surfactant.

By adopting the technical scheme, the sodium, Tween 80 and PEG surfactants can be uniformly and stably coated outside the nano barium ferrite compared with other surfactants to form nano magnetic powder with uniform granularity, so that the magnetism of the nano magnetic powder is improved, and the magnetism of the magnetic plastic is improved.

Preferably, the surfactant comprises a PEG surfactant, which is PEG 4000.

By adopting the technical scheme, the PEG4000 has strong capability of entering an oil-water interface, and the adsorption of the PEG4000 on the interface is not easily influenced by physical factors, so that the PEG4000 can be stably combined with the nano barium ferrite, the dispersibility of the nano magnetic powder is improved, and the magnetism of the magnetic plastic is improved.

Preferably, the magnetic body is prepared by the following method: according to the weight portion, 1-3 portions of nano magnetic powder, 2-4 portions of absolute ethyl alcohol, 3-5 portions of agate balls and 2-4 portions of dispersing material are put into a ball mill according to the mass ratio, and are ball milled for 10-20 hours at the rotating speed of 400 plus materials 600r/min, so as to obtain the magnetic body.

By adopting the technical scheme, the nano magnetic powder and the dispersed material can form uniform and stable combination through ball milling, so that the dispersibility of the magnetic body in the magnetic plastic is improved, and the magnetism of the magnetic material is further improved.

In a second aspect, the present application provides a method for preparing a magnetic plastic, which adopts the following technical scheme:

a preparation method of magnetic plastic comprises the following preparation steps:

s1, primary mixing: according to the formula, mixing and stirring the diatomite, the boron nitride and the viscose fiber to obtain a mixture;

s2, secondary mixing: sequentially adding the low-density polyethylene, the polylactic acid, the magnetic body and the mixture into a temperature-controlled high-speed mixer, and mixing and stirring to obtain a mixed material;

s3, extrusion molding: and adding the mixed materials into a double-screw extruder, melting, extruding and naturally airing to obtain the magnetic plastic.

By adopting the technical scheme, the diatomite, the boron nitride and the viscose fibers with less parts by weight are uniformly mixed by one-time mixing. And then the low-density polyethylene, the polylactic acid, the magnetic body and the mixture are uniformly mixed by a secondary mixing and temperature-controlled high-speed mixer to form a uniform and stable mixed material. And then, mixing the materials to form a melt through a double-screw extruder, extruding and naturally airing to obtain the magnetic plastic.

In summary, the present application has the following beneficial effects:

1. because this application adopts the magnetic substance to add to the magnetism plastics, and the magnetic substance includes nanometer magnetic powder and dispersed material, and nanometer magnetic powder has great magnetism compared in ordinary magnetic powder, simultaneously, the addition of lauryl sodium sulfate forms the combination with nanometer magnetic powder, improves the dispersibility of nanometer magnetic powder, consequently, improves nanometer magnetic powder homodisperse in the magnetism plastics, and then has improved the magnetism of magnetism plastics.

2. The nano barium ferrite in the application is used for enabling the magnetic plastic to have magnetism, the surfactant is used for carrying out surface modification on the nano barium ferrite, the nano barium ferrite is enabled to be well combined with the dispersing material and other components of the magnetic plastic, the nano magnetic powder is further improved, namely the dispersibility of the nano barium ferrite in the magnetic plastic, the core-shell structure is used for enabling the surfactant to be evenly coated on the surface of the nano barium ferrite, the nano barium ferrite and the surfactant have large combining area, the modification effect of the nano barium ferrite is improved, the surface of the nano magnetic powder is enabled to be smooth through the microsphere structure, the lubricity of the nano magnetic powder is improved, the dispersibility of the nano magnetic powder is further improved, and the magnetism of the magnetic plastic is further improved.

3. According to the method, the diatomite, the boron nitride and the viscose fibers which are few in parts by weight are uniformly mixed through one-time mixing, then the mixture is mixed through the second time, the low-density polyethylene, the polylactic acid, the magnetic body and the mixture are uniformly mixed through the temperature-control high-speed mixer to form uniform and stable mixed materials, then the mixed materials are formed into melts through the double-screw extruder, and the magnetic plastic is obtained through extrusion and natural drying.

Detailed Description

The present application will be described in further detail with reference to examples.

In the examples of the present application, the equipment used is shown in Table 1:

table 1 instrument of the examples of the present application

In the examples of the present application, the drugs used are shown in Table 2:

TABLE 2 pharmaceutical products of the examples of the present application

Preparation example of Nano magnetic powder

Preparation example 1

In the preparation example, commercially available nano barium ferrite is used as the nano magnetic powder.

Preparation example 2: the nano magnetic powder of the preparation example is prepared by the following method:

the nano magnetic powder of the preparation example is prepared by the following method:

(1) preparation of a soot-like powder: weighing 1kg of barium carbonate, 8kg of ferric nitrate nonahydrate, 9kg of citric acid and 10kg of water, mixing, stirring at a rotating speed of 100r/min for 10h, then adjusting the pH to 5, and then evaporating and combusting at 50 ℃ to obtain soot-like powder;

(2) and (3) calcining: grinding the soot powder in the step (1) by a grinder to enable the particle size of the soot powder to reach 10 nanometers, and calcining for 10 hours at 850 ℃ to obtain the nano barium ferrite with the particle size of 10 nanometers, namely the nano magnetic powder.

Preparation example 3: the nano magnetic powder of the preparation example is prepared by the following method:

(1) preparation of a soot-like powder: weighing 1kg of barium carbonate, 8kg of ferric nitrate nonahydrate, 9-15kg of citric acid and 10kg of water, mixing, stirring at a rotating speed of 100r/min for 10h, then adjusting the pH to 5, and evaporating and combusting at 50 ℃ to obtain soot-like powder;

(2) and (3) calcining: grinding the soot powder in the step (1) by a grinder to enable the particle size of the soot powder to reach 10 nanometers, and calcining for 10 hours at 850 ℃ to obtain nano barium ferrite with the particle size of 10 nanometers;

(3) coating: and (3) mixing the PEG4000 surfactant and the nano barium ferrite in the step (3) according to a mass ratio of 4: 5 stirring for 20min at the rotating speed of 120r/min after mixing to obtain the nano magnetic powder microspheres with the core-shell structure, namely the nano magnetic powder.

Preparation example 4: the nano magnetic powder of the preparation example is prepared by the following method:

(1) preparation of a soot-like powder: weighing 2kg of barium carbonate, 10kg of ferric nitrate nonahydrate, 12kg of citric acid and 15kg of water, mixing, stirring at a rotating speed of 100r/min for 10h, then adjusting the pH to 5, and then evaporating and combusting at 50 ℃ to obtain soot-like powder;

(2) and (3) calcining: grinding the soot powder in the step (1) by a grinder to enable the particle size of the soot powder to reach 10 nanometers, and calcining for 10 hours at 850 ℃ to obtain nano barium ferrite with the particle size of 10 nanometers;

(3) coating: and (3) mixing the PEG4000 surfactant and the nano barium ferrite in the step (3) according to a mass ratio of 4: 5 stirring for 20min at the rotating speed of 120r/min after mixing to obtain the nano magnetic powder microspheres with the core-shell structure, namely the nano magnetic powder.

Preparation example 5: the nano magnetic powder of the preparation example is prepared by the following method:

(1) preparation of a soot-like powder: weighing 3kg of barium carbonate, 12kg of ferric nitrate nonahydrate, 15kg of citric acid and 20kg of water, mixing, stirring at a rotating speed of 100r/min for 10h, then adjusting the pH to 5, and then evaporating and combusting at 50 ℃ to obtain soot-like powder;

(2) and (3) calcining: grinding the soot powder in the step (1) by a grinder to enable the particle size of the soot powder to reach 10 nanometers, and calcining for 10 hours at 850 ℃ to obtain nano barium ferrite with the particle size of 10 nanometers;

(3) coating: and (3) mixing the PEG4000 surfactant and the nano barium ferrite in the step (3) according to a mass ratio of 4: 5 stirring for 20min at the rotating speed of 120r/min after mixing to obtain the nano magnetic powder microspheres with the core-shell structure, namely the nano magnetic powder.

Preparation example 6: the difference between the preparation example and the preparation example 3 is that:

the preparation example uses sodium oleate surfactant instead of PEG4000 surfactant in preparation example 3.

Preparation example 7: the difference between the preparation example and the preparation example 3 is that:

the preparation example uses tween 80 surfactant instead of the PEG4000 surfactant in preparation example 3.

Preparation example 8: the difference between the preparation example and the preparation example 3 is that:

this preparation example used PEG600 surfactant instead of PEG4000 surfactant in preparation example 3.

Preparation example 9: the difference between the preparation example and the preparation example 3 is that:

the preparation example adopts a silane coupling agent to replace the PEG4000 surfactant in the preparation example 3.

Preparation example 10: the difference between the preparation example and the preparation example 3 is that:

the temperature of calcination in step (2) of this preparation example was 1100 ℃.

Preparation example of magnetic body

Preparation example 11: the magnetic body of the preparation example was prepared by the following method:

2kg of sodium dodecyl sulfate as a dispersion material, 2kg of absolute ethyl alcohol and 1kg of the nano magnetic powder of the preparation example 1 were mixed and stirred at a rotation speed of 400r/min for 15 hours to obtain a magnetic body.

Preparation example 12: the magnetic body of the preparation example was prepared by the following method:

1kg of the magnetic nanoparticles of preparation example 1, 2kg of absolute ethanol, 3kg of agate balls and 2kg of sodium dodecyl sulfate were taken as dispersion materials and put into a ball mill, and ball milling was carried out at a rotation speed of 400r/min for 15 hours to obtain a magnetic body.

Preparation example 13: the magnetic body of the preparation example was prepared by the following method:

1.5kg of the magnetic nanoparticles of preparation example 1, 3kg of absolute ethanol, 4kg of agate balls and 3kg of sodium dodecyl sulfate were taken as dispersion materials and put into a ball mill, and ball milling was carried out at a rotation speed of 400r/min for 15 hours to obtain a magnetic body.

Preparation example 14: the magnetic body of the preparation example was prepared by the following method:

3kg of the magnetic nanoparticles of preparation example 1, 4kg of absolute ethanol, 5kg of agate balls and 4kg of sodium dodecyl sulfate were taken as dispersion materials and put into a ball mill, and ball milling was carried out at a rotation speed of 400r/min for 15 hours to obtain a magnetic body.

Preparation examples 15 to 23: the manufacturing examples 15 to 23 are different from the manufacturing example 12 in the point that the nano-magnetic powder used is different, as shown in table 3.

TABLE 3 selection of the Nanomagnetic powders in preparation examples 15-23

Examples

Example 1: example 1 was prepared as follows:

s1, primary mixing: weighing 40kg of low-density polyethylene, 1kg of diatomite, 1kg of boron nitride, 1kg of viscose, 40kg of polylactic acid and 10kg of magnetic body in preparation example 11, and mixing and stirring the diatomite, the boron nitride and the viscose at the rotating speed of 300r/min according to the formula to obtain a mixture;

s2, secondary mixing: sequentially adding low-density polyethylene, polylactic acid, a magnetic body and a mixture into a temperature-control high-speed mixer, adjusting the temperature of the temperature-control high-speed mixer to be 40 ℃, and mixing and stirring at the rotating speed of 800r/min for 10min to obtain a mixed material;

s3, extrusion molding: adding the mixed materials into a double-screw extruder, setting the rotating speed of the double-screw extruder to be 300rpm, and setting the temperature of each temperature zone to be: the 1 st temperature zone is 150 ℃, the 2 nd-9 th temperature zone is 170 ℃, the 10 th-11 th temperature zone is 160 ℃, and the magnetic plastic is obtained by extrusion and natural drying after melting.

Example 2: example 2 was prepared as follows:

s1, primary mixing: weighing 45kg of low-density polyethylene, 1.5kg of diatomite, 2kg of boron nitride, 2kg of viscose, 50kg of polylactic acid and 15kg of magnetic body in preparation example 11, and mixing and stirring the diatomite, the boron nitride and the viscose at the rotating speed of 300r/min according to the formula to obtain a mixture;

s2, secondary mixing: sequentially adding low-density polyethylene, polylactic acid, a magnetic body and a mixture into a temperature-control high-speed mixer, adjusting the temperature of the temperature-control high-speed mixer to be 40 ℃, and mixing and stirring at the rotating speed of 800r/min for 10min to obtain a mixed material;

s3, extrusion molding: adding the mixed materials into a double-screw extruder, setting the rotating speed of the double-screw extruder to be 300rpm, and setting the temperature of each temperature zone to be: the 1 st temperature zone is 150 ℃, the 2 nd-9 th temperature zone is 170 ℃, the 10 th-11 th temperature zone is 160 ℃, and the magnetic plastic is obtained by extrusion and natural drying after melting.

Example 3: example 3 was prepared as follows:

s1, primary mixing: weighing 50kg of low-density polyethylene, 2kg of diatomite, 3kg of boron nitride, 3kg of viscose, 60kg of polylactic acid and 20kg of magnetic body in preparation example 11, and mixing and stirring the diatomite, the boron nitride and the viscose at the rotating speed of 300r/min according to the formula to obtain a mixture;

s2, secondary mixing: sequentially adding low-density polyethylene, polylactic acid, a magnetic body and a mixture into a temperature-control high-speed mixer, adjusting the temperature of the temperature-control high-speed mixer to be 40 ℃, and mixing and stirring at the rotating speed of 800r/min for 10min to obtain a mixed material;

s3, extrusion molding: adding the mixed materials into a double-screw extruder, setting the rotating speed of the double-screw extruder to be 300rpm, and setting the temperature of each temperature zone to be: the 1 st temperature zone is 150 ℃, the 2 nd-9 th temperature zone is 170 ℃, the 10 th-11 th temperature zone is 160 ℃, and the magnetic plastic is obtained by extrusion and natural drying after melting.

Examples 4 to 15: examples 4 to 15 differ from example 1 in the magnetic material selected, as shown in table 4.

TABLE 4 selection of magnetic bodies in examples 4 to 15

Comparative example

Comparative example 1

The magnetic body of the present comparative example contains only the nano-magnetic powder, which is a commercially available nano-barium ferrite.

Performance test

Magnetic performance detection method

And (3) detecting by using a vibration sample magnetometer according to the use instruction, and testing the magnetization intensity of the magnetic plastic.

TABLE 5 Performance test Table

Examples 1-3 were compared, but examples 1-3 were different in the ratio of the magnetic plastic material, and example 2 had the highest magnetization, so example 2 had the best magnetic properties, and thus example 2 had the best ratio of the material.

Example 4 was compared with example 1, and example 4 was different from example 1 in that example 1 and example 4 were successively added to a quick setting material using the magnetic bodies of preparation example 11 and preparation example 12, and the magnetic bodies of preparation example 11 and preparation example 12 were different in preparation method. The method of preparing the magnetic body in example 4 is more preferable because the magnetization of example 4 is higher and thus the magnetic property of example 4 is better.

Examples 4 to 6 were compared, and examples 4 to 6 were different in that examples 4 to 6 were prepared by sequentially adding the magnetic materials of preparation examples 12 to 14 to the magnetic plastic, and preparation examples 12 to 14 were different in that the magnetic materials were prepared in different proportions, and example 5 had the highest magnetization, so that the magnetic material of example 5 was the strongest and the proportion of the magnetic material of example 5 was the best.

Example 7 was compared with example 4, and example 7 was different from example 4 in that example 7 and example 4 were added to a magnetic plastic using the magnetic bodies of preparation example 15 and preparation example 12 in this order, and the magnetic body of preparation example 15 was different from the magnetic body of preparation example 12 in that preparation example 15 used the nano-magnetic powder of preparation example 2 and preparation example 12 used the nano-magnetic powder of preparation example 1. The nano magnetic powder of preparation example 1 was a commercially available nano barium ferrite, and the nano magnetic powder of preparation example 2 was a nano barium ferrite prepared by the method in the present application. The nano barium ferrite prepared by the method of the present application is superior because the magnetization of example 7 is high, and thus the magnetic property of example 7 is high.

Example 8 was compared with example 7, and example 8 was different from example 7 in that example 8 and example 7 were sequentially added to a magnetic plastic using the magnetic bodies of production example 16 and production example 15, and the magnetic body of production example 16 was different from the magnetic body of production example 15 in that production example 16 used the nano-magnetic powder of production example 3 and production example 15 used the nano-magnetic powder of production example 2. The difference between the preparation example 3 and the preparation example 2 is that the PEG4000 surfactant is added in the step (3) in the preparation example 3, so as to prepare the nano magnetic powder microsphere with the core-shell structure. The magnetization intensity of the embodiment 8 is higher, so the magnetism of the embodiment 8 is higher, and the magnetic property of the magnetic plastic is improved by adding the PEG4000 surfactant to prepare the nanometer magnetic powder microsphere with the core-shell structure.

Examples 8 to 10 were compared, and examples 8 to 10 were different in that examples 8 to 10 were sequentially prepared by adding the magnetic materials of preparation examples 16 to 18 to a magnetic plastic, and the magnetic materials of preparation examples 16 to 18 were sequentially prepared by using the magnetic nanoparticles of preparation examples 3 to 5, and preparation examples 3 to 5 were different in that the ratio of raw materials was different when preparing the magnetic nanoparticle microspheres of core-shell structure, whereas example 9 had the highest magnetization intensity, so that the magnetic property of example 9 was the strongest, and the ratio of raw materials was the best when preparing the magnetic nanoparticle microspheres of core-shell structure in example 9.

Examples 11-14 are compared, with examples 11-14 differing in the surfactants selected, with example 11 having the highest magnetization and therefore the best magnetic properties, and therefore the best PEG4000 surfactant, used in example 11, being the best magnetic properties, because of example 11.

Finally, comparing comparative example 1 with example 1, comparative example 1 is different from example 1 in that the magnetic body of comparative example 1 contains only nano-magnetic powder using commercially available nano-barium ferrite, and the magnetic property of example 1 is higher because the magnetization of example 1 is higher, so the addition of the dispersion material improves the magnetic property of the magnetic plastic.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.