Modified magnetic wood powder, functional wood-plastic composite material and preparation method thereof

Abstract

The application discloses modified magnetic wood powder and a preparation process thereof, and is prepared by loading ferroferric oxide particles on the surface of wood powder through in-situ synthesis and combining with modification treatment. The modified magnetic wood powder has good dispersibility in water, can effectively adsorb micro-nano plastic particles in a solution, and can be removed from the solution by using a magnet. The modified magnetic wood powder adsorbed with the micro-nano plastic particles is subjected to hot-pressing forming to prepare functional wood-plastic composite materials with excellent physical and mechanical properties, magnetism, electromagnetic wave absorption and flame retardancy, and realizes the reuse of the magnetic particle materials after adsorbing the micro-nano plastic particles. The application can effectively adsorb and remove micro-nano plastics in water, and simultaneously realizes the high-value utilization of the adsorbed materials, has the advantages of simple operation, low cost and sustainability, and solves the problems of micro-plastic pollution treatment and the reuse of the treated materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage purification and waste recycling, and particularly relates to modified magnetic wood powder, a functional wood-plastic composite material prepared from the modified magnetic wood powder for adsorbing micro-nano plastic in a solution and a preparation method thereof. BACKGROUND

[0002] In recent years, the degree of plastic pollution in the environment has shown a continuous upward trend. Plastic accumulates in the environment, causing the environment, such as water, soil, and air, on which humans rely for survival to be polluted. Micro-nano plastic refers to plastic particles with a particle size in the range of 1 nm to 5 μm. Due to its small size, micro-nano plastic particles can enter the body through water, food, or air, reach organs and tissues of the body, cause physiological changes, structural damage, and dysfunction, and pose a potential threat to human health. Therefore, it is very urgent to separate micro-nano plastic particles from their existing medium, especially water environment, using appropriate methods.

[0003] There are many ways to treat micro-nano plastic particles in the traditional water treatment industry, such as membrane bioreactor (MBR), rapid sand rate method, dissolved air flotation (DAF), etc. These methods have high removal efficiency for microplastics with a particle size greater than 20 μm, but they are not suitable for removing small-sized micro-nano plastics. In addition, there are methods such as flocculation, filtration, and microalgae adsorption. The flocculation method separates micro-nano plastic particles from water by co-sedimentation, which has low processing cost, but can cause secondary pollution. The filtration method uses high porosity and small pore size filter media, which has high removal efficiency, but still cannot completely retain small-sized micro-nano plastics, and the filter media will be clogged after long-term use. The microalgae adsorption method does not use chemical reagents, but it is difficult to recover the adsorbed micro-nano plastics, and the microalgae will be toxic.

[0004] To solve the above problems, nano-sized magnetic particles are ideal materials for treating micro-nano plastic particles in water due to their own charge characteristics. After adjusting the electric potential, the magnetic particles can adsorb charged micro-nano plastic particles through charge interaction. Among them, magnetic iron oxide nanoparticles can adsorb nano-sized polystyrene (PS), polymethyl methacrylate (PMMA), polyethylene (PE), and other micro-nano plastic particles, and then remove them from water by applying an external magnetic field. However, nano-sized magnetic particle adsorption materials are prone to agglomeration during water treatment, affecting their dispersion in water and reducing their adsorption capacity for micro-nano plastic particles. In addition, the magnetic particle materials after adsorbing micro-nano plastic have low desorption efficiency and cannot be further used, resulting in insufficient utilization of the materials.

[0005] Therefore, how to improve the dispersibility of the nano magnetic particles in water to improve the adsorption efficiency of the nano magnetic particles on the micro-nano plastic particles, and recycle the nano magnetic particle material after adsorbing the micro-nano plastic particles, is an urgent problem to be solved. SUMMARY

[0006] In order to solve the problems in the above background art, the present application provides a modified magnetic wood powder and a preparation process thereof, the modified magnetic wood powder has good dispersibility in a solution and can effectively adsorb micro-nano plastic particles in a solution containing the micro-nano plastic particles, and the modified magnetic wood powder can be removed from the solution by using a magnet. In addition, the present application also provides a functional wood-plastic composite material and a preparation method thereof, which realizes the recycling of the nano magnetic particle material after adsorbing the micro-nano plastic particles, and the modified magnetic wood powder after adsorbing the micro-nano plastic particles in the solution is hot-pressed to prepare a functional wood-plastic composite material having excellent physical and mechanical properties, magnetism, electromagnetic wave absorption and flame retardancy.

[0007] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0008] In a first aspect of the present application, a preparation method of a modified magnetic wood powder is provided, comprising the following steps:

[0009] S1, preparation of magnetic wood powder:

[0010] The wood powder with a mesh size of 50-150 is reacted with ferric chloride hexahydrate, ferrous chloride tetrahydrate and ammonia water to prepare the magnetic wood powder.

[0011] S2, preparation of modified magnetic wood powder:

[0012] The hexadecyl trimethoxysilane is dissolved in methanol, and then the magnetic wood powder is added thereto, and after ultrasonic reaction, washing and drying treatment, the modified magnetic wood powder is obtained.

[0013] The above technical solutions are adopted:

[0014] Firstly, the surface of the wood powder contains a large number of hydroxyl groups, which can form a complex with metal ions (Fe 3+ and Fe 2+ ) in ferric chloride and ferrous chloride, and the metal ions are adsorbed on the surface of the wood powder. After adding ammonia water, it reacts with Fe 3+ and Fe 2+ adsorbed on the surface of the wood powder.The ion generation reaction forms water-insoluble iron hydroxide (Fe(OH)3) and ferrous hydroxide (Fe(OH)2) precipitates, which are deposited on the surface of the wood powder and ultimately form a magnetic material on the surface of the wood powder after subsequent conversion. Then, the magnetic wood powder is modified by treating it with hexadecyl trimethoxysilane (HDTMS). The hydrophobic long-chain alkyl group of HDTMS is grafted onto the surface of the wood powder, improving the dispersion effect and dispersion stability of the magnetic wood powder in water and reducing the agglomeration phenomenon. The magnetic wood powder can effectively adsorb micro-nano plastic particles in a solution containing the micro-nano plastic particles, thereby more thoroughly adsorbing the micro-nano plastic particles in the water body. In addition, the magnetic property of the magnetic wood powder is beneficial for separating the adsorbed particles from the water body using an external magnetic field, without causing secondary pollution to the water body environment.

[0015] Further, the step S2 is specifically: dissolving hexadecyl trimethoxysilane into methanol to obtain a mixed solution with a volume concentration of 1-8%, adding magnetic wood powder to the mixed solution, and then ultrasonic treating for 3-5 min. The modified magnetic wood powder is removed from the solution under the action of a magnet, washed with methanol, and dried in an oven to obtain the modified magnetic wood powder.

[0016] Further, in the step S1, the wood powder is pretreated by stirring the wood powder in an ethanol solution with a volume concentration of ≥20% at 50-80°C for 1-3 h. The pretreated wood powder is separated and washed with deionized water, and then dried to obtain the pretreated wood powder.

[0017] The wood powder is pretreated with ethanol to change the surface properties of the wood powder and make it a good carrier for magnetic particles.

[0018] Further, in the step S1, the preparation process of the magnetic wood powder is specifically: preparing a mixed solution of iron chloride hexahydrate with a mass concentration of 10-30% and ferrous chloride tetrahydrate with a mass concentration of 5-10%, adding wood powder to the mixed solution, and vacuum impregnating for 1-5 h. After impregnation, an ammonia solution with the same volume as the mixed solution is added, and the mixture is stirred uniformly and then vacuum impregnated for another 1-5 h. After complete impregnation, the magnetic wood powder is removed from the solution under the action of a magnet to obtain the magnetic wood powder loaded with iron oxide particles.

[0019] In a second aspect, the application provides a modified magnetic wood powder prepared by the above preparation method.

[0020] Through test, the maximum adsorption rate of the prepared modified magnetic wood powder for micro-nano plastic particles in water is 2571 mg / g.

[0021] In a third aspect, the application provides a preparation method of a functional wood-plastic composite material, which comprises the following steps:

[0022] (1) adsorbing micro-nano plastic particles in water:

[0023] The modified magnetic wood powder prepared above is added to a solution containing micro-nano plastic particles for stirring adsorption, then the modified magnetic wood powder adsorbed with micro-nano plastic particles is removed from the solution by a magnet, and then dried;

[0024] (2) wood-plastic composite material preparation:

[0025] The modified magnetic wood powder adsorbed with micro-nano plastic particles after drying treatment is added to a hot-pressing mold, and a functional wood-plastic composite material is obtained through hot-pressing forming treatment.

[0026] By adopting the technical scheme above:

[0027] In the present application, the modified magnetic wood powder adsorbed with micro-nano plastic particles is prepared into a functional wood-plastic composite material through hot-pressing forming. Compared with ordinary wood-plastic composite materials, the plastic component of the functional wood-plastic composite material comes from water bodies, which not only realizes the removal of micro-nano plastic pollutants in wastewater, but also realizes the recycling of waste resources (waste wood powder and micro-nano plastic particles in wastewater). The functional wood-plastic composite material prepared has not only good strength, but also more special functions, such as magnetism, flame retardancy and electromagnetic wave absorption function, and can be widely used in the field of engineering construction.

[0028] Further, in the step (2), the hot-pressing forming treatment is specifically: hot-pressing time 30-60 min, pressure 5-20 MPa, temperature 120-220℃.

[0029] Further, the step (1) is specifically: the modified magnetic wood powder prepared is placed in a solution containing micro-nano plastic particles, and stirring is carried out at 20-60℃ and a rotation speed of 300-500 rpm / min for more than 20 min. After stirring, the modified magnetic wood powder adsorbed with micro-nano plastic particles is removed from the solution by a magnet, and then dried.

[0030] Further, the micro-nano plastic particles contained in the solution are thermoplastic plastic, the size of the micro-nano plastic particles is 50 nm-5 μm, and the pH value of the solution containing micro-nano plastic particles is 2-9.

[0031] In a fourth aspect, the present application provides a functional wood-plastic composite material prepared by the preparation method.

[0032] Compared with the prior art, the present application has the following beneficial effects:

[0033] (1) The raw material wood powder is a common processing residue in the wood industry, which is low-carbon, environmentally friendly, easy to obtain, and low in cost. The wood powder has a large specific surface area and low processing difficulty. The surface properties of the wood powder can be changed by pretreating the wood powder with ethanol, so that the wood powder can become an excellent carrier for magnetic particles.

[0034] (2) The wood powder loaded with magnetic particles on the surface is modified. The magnetic wood powder is treated with hexadecyltrimethoxysilane (HDTMS), and the hydrophobic long-chain alkyl group of HDTMS is grafted onto the surface of the wood powder, which improves the dispersion effect and dispersion stability of the magnetic wood powder in water and reduces the agglomeration phenomenon. The magnetic wood powder can effectively adsorb micro-nano plastic particles in a solution containing micro-nano plastic particles, thereby more thoroughly adsorbing micro-nano plastic particles in water. In addition, the magnetic property of the modified magnetic wood powder is beneficial for separating the adsorbed particles from water using an external magnetic field, and does not cause secondary pollution to the water environment.

[0035] (3) The modified magnetic wood powder has excellent adsorption effect on various plastic particle pollutants in the water environment, including different sizes, micrometer and nanometer, and different types, such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polymethyl methacrylate (PMMA), and polycarbonate (PC). The modified magnetic wood powder is also applicable in different acid and alkaline environments and has universality. The maximum adsorption efficiency of the modified magnetic wood powder is 2571 mg / g.

[0036] (4) The modified magnetic wood powder loaded with micro-nano plastic particles is then hot-pressed to prepare a functional wood-plastic composite material. Compared with ordinary wood-plastic composite materials, the plastic component of the functional wood-plastic composite material comes from the water, which not only removes micro-nano plastic pollutants in wastewater, but also recycles waste resources (waste wood powder and micro-nano plastic particles in wastewater).

[0037] (5) Due to the loaded magnetic particles, the functional wood-plastic composite material prepared from the modified magnetic wood powder loaded with micro-nano plastic particles has not only good strength, but also more special functions, such as magnetism, flame retardancy, and electromagnetic wave absorption function, which can be widely used in the field of engineering construction. BRIEF DESCRIPTION OF DRAWINGS

[0038] The present application will be further described in detail below with reference to the accompanying drawings and specific examples.

[0039] Figure 1 The flowchart for preparing a functional wood-plastic composite material from the modified magnetic wood powder loaded with micro-nano plastic particles in the present application is shown in the figure.

[0040] Figure 2 The scanning electron microscope image of the modified magnetic wood powder prepared in Example 1 is shown in the figure.

[0041] Figure 3 Adsorption amount of modified magnetic wood powder prepared for example 1-4 on PS and PMMA plastic particles of 5pm and 400nm changes with adsorption time chart;

[0042] Figure 4 The functional wood-plastic composite material obtained by hot pressing of the modified magnetic wood powder prepared for example 2 after adsorbing PS plastic particles is attracted by a magnet, and its magnetization curve is shown in the figure;

[0043] Figure 5 The functional wood-plastic composite material obtained by hot pressing of the modified magnetic wood powder prepared for example 2 after adsorbing PS plastic particles is attracted by a magnet, and its magnetization curve is shown in the figure; DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0045] Example 1

[0046] A method for preparing a functional wood-plastic composite material from magnetic wood powder adsorbing micro-nano plastic particles in water, as shown in Figure 1 , comprising the following steps:

[0047] (1) Wood powder of 60 mesh is screened out using a powder screen, and the wood powder is placed in an ethanol solution with a concentration of 65%, stirred and treated at 70°C for 2h, then separated out using a suction filtration device and washed with deionized water, and then moved into an oven to dry to absolute dryness to obtain pretreated wood powder.

[0048] (2) A mixed solution of ferric chloride hexahydrate with a mass concentration of 15% and ferrous chloride tetrahydrate with a mass concentration of 7% is configured, then the pretreated wood powder is added, vacuum impregnated for 3h; after impregnation, an ammonia water solution with the same volume as the mixed solution is added, stirred uniformly, and then vacuum impregnated for another 3h; after complete impregnation, the magnetic wood powder is removed from the solution under the action of a magnet, and magnetic wood powder loaded with iron oxide particles is prepared.

[0049] (3) Hexadecyl trimethoxysilane is dissolved in methanol to obtain a mixed solution with a volume concentration of 5%, and the magnetic wood powder is added, ultrasonically treated for 5min, then the modified magnetic wood powder is removed from the solution under the action of a magnet, washed with methanol, and then dried to absolute dryness in an oven to obtain modified magnetic wood powder.

[0050] (4) The prepared modified magnetic wood powder is placed in water containing 5 pm PS plastic particles, stirred at a temperature of 25°C and a rotation speed of 300 rpm / min for more than 80 min, and then the modified magnetic wood powder adsorbed with micro-nano plastic particles is removed from the solution under the action of a magnet, and then dried in a drying oven at 70°C.

[0051] (5) The dried modified magnetic wood powder adsorbed with micro-nano plastic particles is loaded into a hot-pressing mold for hot-pressing molding, wherein the hot-pressing time is 40 min, the pressure is 10 MPa, the temperature is 180°C, and the thickness of the plate is controlled to be 5 mm by using a thickness gauge, and finally a functional wood-plastic composite material is obtained.

[0052] Example 2

[0053] The difference between this example and Example 1 is that:

[0054] In step (4), the prepared modified magnetic wood powder is placed in water containing 400 nm PS plastic particles.

[0055] The others are the same as Example 1.

[0056] Example 3

[0057] The difference between this example and Example 1 is that:

[0058] In step (4), the prepared modified magnetic wood powder is placed in water containing 5 pm PMMA plastic particles.

[0059] The others are the same as Example 1.

[0060] Example 4

[0061] The difference between this example and Example 1 is that:

[0062] In step (4), the prepared modified magnetic wood powder is placed in water containing 400 nm PMMA plastic particles.

[0063] The others are the same as Example 1.

[0064] Comparative Example 1

[0065] The wood powder without any treatment is directly mixed with 5 pm PS plastic particles and loaded into a hot-pressing mold for hot-pressing molding, and the ratio of wood powder to plastic is the same as the calculated value of plastic adsorption in Example 1, and the hot-pressing time is 40 min, the pressure is 10 MPa, the temperature is 180°C, and the thickness of the plate is controlled to be 5 mm by using a thickness gauge, and finally a common wood-plastic composite material is obtained.

[0066] Comparative Example 2

[0067] The wood powder without any treatment was directly mixed with 400 nm PS plastic particles and loaded into a hot-pressing mold for hot-pressing molding, the ratio of wood powder to plastic was kept the same as the calculated value of plastic adsorption in Example 1, the hot-pressing time was 40 min, the pressure was 10 MPa, the temperature was 180℃, the thickness of the plate was controlled to be 5 mm by using a thickness gauge, and finally a common wood-plastic composite material was prepared.

[0068] Comparative Example 3

[0069] The wood powder without any treatment was directly mixed with 5 μm PMMA plastic particles and loaded into a hot-pressing mold for hot-pressing molding, the ratio of wood powder to plastic was kept the same as the calculated value of plastic adsorption in Example 1, the hot-pressing time was 40 min, the pressure was 10 MPa, the temperature was 180℃, the thickness of the plate was controlled to be 5 mm by using a thickness gauge, and finally a common wood-plastic composite material was prepared.

[0070] Comparative Example 4

[0071] The wood powder without any treatment was directly mixed with 400 nm PMMA plastic particles and loaded into a hot-pressing mold for hot-pressing molding, the ratio of wood powder to plastic was kept the same as the calculated value of plastic adsorption in Example 1, the hot-pressing time was 40 min, the pressure was 10 MPa, the temperature was 180℃, the thickness of the plate was controlled to be 5 mm by using a thickness gauge, and finally a common wood-plastic composite material was prepared.

[0072] Application Example 1

[0073] The modified magnetic wood powder prepared in Example 1 was subjected to scanning electron microscope analysis, and the results are shown in Figure 2 The scanning electron microscope results of Figure 2 can be seen that a layer of ferroferric oxide particles is loaded on the surface of the wood powder, which indicates that the modified magnetic wood powder is successfully prepared according to the steps of the application.

[0074] Subsequently, the modified magnetic wood powder prepared in Examples 1-4 was subjected to adsorption performance test, and the test results are shown in Figure 3 and Table 1.

[0075] Table 1 Adsorption amount of modified magnetic wood powder to PS and PMMA plastic

[0076] Number Plastic kind and size Adsorption amount (mg / g) Example 1 5 μm PS 2571±37 Example 2 400 nm PS 186.4±5.3 Example 3 5 μm PMMA 2544±47 Example 4 400 nm PMMA 103.7±12.2

[0077] From Figure 3From Table 1, it can be seen that the modified magnetic wood powder prepared in Examples 1-4 has good adsorption capacity for PS and PMMA in water, and the modified magnetic wood powder has better adsorption capacity for micro-sized plastic particles. In addition, the adsorption capacity of the modified magnetic wood powder in Examples 1-4 for plastic particles increases with the extension of the adsorption time, and reaches adsorption saturation at about 80 min.

[0078] Application Example 2

[0079] The functional wood-plastic composite materials prepared in Examples 1 and 3 and the ordinary wood-plastic composite materials prepared in Comparative Examples 1 and 3 were subjected to mechanical and water absorption tests, and the test results are shown in Table 2. A mechanical testing machine was used to test the bending and tensile strength of all the samples to be tested. The samples to be tested were dried in a drying oven until dry, and the weight and thickness values were recorded. Then the samples were placed in a water tank containing deionized water, and after 20 days of immersion, the weight and thickness were measured, and the weight change rate and water absorption thickness expansion rate of the samples before and after water absorption were calculated.

[0080] Table 2 Mechanical strength and water absorption of functional wood-plastic composite materials and ordinary wood-plastic composite materials

[0081]

[0082] From Table 2, it can be seen that the functional wood-plastic composite materials prepared in Examples 1 and 3 have significantly increased bending strength and tensile strength compared with the ordinary wood-plastic composite materials prepared in Comparative Examples 1 and 3. In particular, the bending strength of Example 1 is about 4.4 times higher than that of Comparative Example 1, which indicates that the functional wood-plastic composite material prepared by the present application has better mechanical properties. In addition, the functional wood-plastic composite material exhibits lower water absorption rate and water absorption thickness expansion than the ordinary wood-plastic composite material, which also indicates that it has better dimensional stability. The improvement in these physical and mechanical properties indicates that the functional wood-plastic composite material prepared by adsorbing micro-nano plastic can be suitable for engineering materials.

[0083] Application Example 3

[0084] The functional wood-plastic composite materials prepared in Examples 2 and 4 and the ordinary wood-plastic composite materials prepared in Comparative Examples 2 and 4 were subjected to magnetic, flame retardant and wave absorption performance tests. A vibrating sample magnetometer was used to test the magnetism of the samples, a cone calorimeter was used to test the combustion performance according to the ISO5660-1 standard, and a microwave network vector analyzer was used to test the wave absorption performance of the samples.

[0085] Table 3 Flame retardant properties of functional wood-plastic composite materials and ordinary wood-plastic composite materials

[0086]

[0087] From Figure 4and Figure 5 It can be seen that the functional wood-plastic composite material prepared in Example 2 can be easily attracted by a magnet without falling off; and the magnetic saturation strength of Example 2 reaches 10.6 emu / g, while Comparative Example 2 has no magnetic strength and does not have magnetism. The magnetism of Example 2 is mainly due to the fact that the component contains iron oxide particles, and the obvious Fe element can be observed from the elemental scanning result. Therefore, the iron oxide particles contained in the functional wood-plastic composite material prepared in Example 2 endow it with excellent absorption performance, and the maximum electromagnetic wave absorption value thereof in the range of 2-18 GHz reaches -22.4 dB.

[0088] It can be seen from the flame retardant test results in Table 3 that the heat release rate and total heat release amount of the functional wood-plastic composite material prepared in Example 2 and Example 4 are smaller than those of the ordinary wood-plastic composite material of Comparative Example 2 and Comparative Example 4. Among them, the peak heat release rate and total heat release amount of Example 4 relative to Comparative Example 4 are lowered by 34% and 26.8%, respectively; and in terms of smoke release amount, Example 4 is lowered by 85.7% relative to Comparative Example 4. It can be seen that by preparing modified magnetic wood powder, the present application can not only efficiently adsorb micro-nano plastic in water, but also the functional wood-plastic composite material prepared by the wood powder after adsorption has excellent physical and mechanical properties and special functions of magnetism, wave absorption and flame retardancy.

[0089] Although the embodiments of the present application have been shown and described, it can be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a functional wood plastic composite, characterized in that, It comprises the following steps: (1) Adsorbing micro-nano plastic particles in water: The modified magnetic wood powder is added to the solution containing micro-nano plastic particles for stirring adsorption, and then the modified magnetic wood powder adsorbed with micro-nano plastic particles is removed from the solution by a magnet, and then dried; (2) Wood-plastic composite material preparation: The modified magnetic wood powder adsorbed with micro-nano plastic particles after drying treatment is added to a hot pressing mold, and a functional wood-plastic composite material is obtained after hot pressing forming treatment. The preparation method of the modified magnetic wood powder is as follows: S1, Preparation of magnetic wood powder: The wood powder with a mesh size of 50-150 is reacted with ferric chloride hexahydrate, ferrous chloride tetrahydrate and ammonia water to prepare magnetic wood powder loaded with magnetite particles; S2, Preparation of modified magnetic wood powder: Hexadecyl trimethoxysilane is dissolved in methanol, and then magnetic wood powder is added thereto, and after ultrasonic reaction, washing and drying treatment, modified magnetic wood powder is obtained.

2. The method of claim 1, wherein the functional wood plastic composite is prepared by mixing the wood powder, the thermoplastic resin, the coupling agent, and the functional additive. Step S2 is specifically: hexadecyl trimethoxysilane is dissolved in methanol to obtain a mixed solution with a volume concentration of 1-8%, magnetic wood powder is added thereto, and after ultrasonic treatment for 3-5 min, the modified magnetic wood powder is removed from the solution under the action of a magnet, then washed with methanol, and dried in an oven to prepare the modified magnetic wood powder. 3.The method of claim 1, wherein the functional wood plastic composite is prepared by mixing the wood powder, the thermoplastic resin, and the functional material in a ratio of 60:30:10 to 80:10:

10. In step S1, the wood powder is pretreated by stirring in an ethanol solution with a volume concentration of ≥20% at 50-80°C for 1-3 h, and then the treated wood powder is separated and washed with deionized water, and then dried to obtain pretreated wood powder.

4. The method of claim 1 or 3, wherein the functional wood plastic composite is prepared by mixing the wood powder, the thermoplastic resin, and the functional material, and then extruding the mixture. In step S1, the preparation process of the magnetic wood powder is specifically: a mixed solution of ferric chloride hexahydrate with a mass concentration of 10-30% and ferrous chloride tetrahydrate with a mass concentration of 5-10% is prepared, and wood powder is added to the mixed solution for vacuum immersion for 1-5 h; After immersion, an ammonia water solution with the same volume as the mixed solution is added, stirred uniformly, and then vacuum immersed for 1-5 h; After complete immersion, the magnetic wood powder is removed from the solution under the action of a magnet to obtain magnetic wood powder loaded with magnetite particles. 5.The method of claim 1, wherein the functional wood plastic composite is prepared by mixing the wood powder, the thermoplastic resin, and the functional material. In step (2), the hot pressing forming treatment is specifically: hot pressing time is 30-60 min, pressure is 5-20 MPa, and temperature is 120-220°C. 6.The method of claim 1, wherein the functional wood plastic composite is prepared by mixing the wood powder, the thermoplastic resin, and the functional material in a ratio of 60:30:10 to 80:10:

10. Step (1) is specifically: the prepared modified magnetic wood powder is placed in a solution containing micro-nano plastic particles, stirred at 20-60°C and a rotation speed of 300-500 rpm for more than 20 min, the modified magnetic wood powder adsorbed with micro-nano plastic particles is removed from the solution by a magnet after stirring, and then dried.

7. The method for preparing the functional wood-plastic composite material according to claim 1 or 6, characterized in that, The micro-nano plastic particles in the solution are thermoplastic, the size of the micro-nano plastic particles is 50 nm-5 μm, and the pH value of the solution containing micro-nano plastic particles is 2-9.

8. A functional wood plastic composite, characterized by It is prepared by the preparation method of any one of claims 1-7. It is prepared by the preparation method of any one of claims 1-7.

Images