Preparation method of friction-wear-resistant rape straw / polyvinyl chloride wood-plastic composite material
By performing low-temperature crushing and removing ginger core components on rape straw, combined with the preparation of multi-micron wear-resistant fillers and uniform dispersion technology, the problem of ginger core components in composite materials affecting performance is solved, significantly improving wear resistance and overall performance, and achieving high-value utilization of rape straw.
Patent Information
- Application Number
- CN202510258048.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-05
- Publication Date
- 2025-05-13
AI Technical Summary
The prior art is difficult to effectively remove the tartar components in rapeseed straw, resulting in a decrease in strength and toughness of the composite material. Moreover, a variety of fillers are difficult to disperse uniformly in the PVC matrix, and the wear resistance of the wood-plastic composite material cannot be fully improved.
The core components of the rape straw were removed by low temperature crushing and pneumatic flotation, and the residual core was removed by heating and soaking in a mixed solution of sodium sulfite and hydrogen peroxide. At the same time, nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a specific proportion, and multi-micron-scale wear-resistant fillers are prepared through ultrasonic dispersion and high-energy ball milling. Combined with ultrasonic assisted dispersion and spray drying technology, the uniform dispersion of the fillers is achieved.
It significantly improves the friction and wear resistance of composite materials, enhances the overall performance, and realizes the high-value utilization of rapeseed straw. It has simple process and low cost, and has good economic and environmental benefits.
Smart Images
Figure CN119978664A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of composite material preparation, and in particular to a method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material. Background Art
[0002] As an important part of the sustainable development strategy, the treatment and resource utilization of agricultural waste has received extensive attention. Rapeseed straw is a large amount of waste generated during rapeseed cultivation. If it is not properly treated, it will cause waste of resources and cause environmental pollution. Therefore, converting rapeseed straw into high-value-added materials and realizing its resource utilization has important economic and environmental significance.
[0003] Wood-plastic composites have been widely used in many fields such as construction, packaging, and electronics due to their good processing properties, chemical stability, electrical insulation, and relatively low cost. However, their poor wear resistance limits their application in scenarios with high requirements for wear resistance.
[0004] The structure of rapeseed straw is relatively complex. The core part is loose in texture and mainly composed of thin-walled cells. It has significant differences in physical and chemical properties from the external phloem part. Existing technologies often fail to fully recognize the negative impact of the core components on the performance of composite materials and fail to take effective measures to completely remove the core. The remaining core is like a "weak point" in the composite material. When subjected to external forces, it can easily become the source of cracks, resulting in reduced strength and toughness of the composite material, seriously affecting the overall performance of the material.
[0005] In the field of composite materials, friction and wear performance is a key indicator to measure material quality and application scope. In order to improve the wear resistance of PVC, the industry often adds traditional wear-resistant fillers. However, these fillers have poor compatibility with the PVC matrix, are difficult to disperse evenly, and are easy to agglomerate to produce stress concentration points, which cause crack propagation during friction. Not only can they not effectively improve the wear resistance, but they also reduce the comprehensive mechanical properties of the material, such as tensile strength and impact toughness.
[0006] In the process of preparing composite fillers and blending them with straw, due to the large differences in particle size, surface properties, etc. of various fillers, it is difficult to achieve their uniform dispersion in straw and PVC matrices with existing technologies. Micron materials are prone to agglomeration due to their small particle size and large specific surface area, and are difficult to be evenly distributed in the matrix, thus failing to fully exert the synergistic reinforcement effect between the components, resulting in limited performance improvement of the composite materials.
[0007] In summary, there are many technical bottlenecks in the use of rape straw to prepare high-performance wood-plastic composites. Developing a preparation method that can effectively remove the adverse components that affect the performance, make full use of the advantageous components of rape straw, and achieve uniform dispersion of multiple fillers in the PVC matrix, improve the wear resistance of wood-plastic composites, and ensure the stability of the composite material performance is of vital practical significance for promoting the resource utilization of agricultural waste and expanding the application field of wood-plastic composites. Summary of the invention
[0008] Based on the above background technology and the problem that rape straw / / PVC wood-plastic composite materials have poor friction and wear resistance, the present invention aims to provide a method for preparing a friction and wear resistant rape straw / PVC composite material, which improves the friction and wear resistance of the composite material by special treatment of rape straw and reasonable preparation and application of multi-component composite wear-resistant fillers, thereby achieving high-value utilization of rape straw and improvement of the friction and wear resistance of the composite material.
[0009] To achieve the above object, the present invention is implemented through the following technical solutions: A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry, cut the rapeseed straw into sections, and then preliminarily crush it in a dry and low-temperature environment at -10℃~-20℃; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 4: Preparation of support filler: Disperse the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a water solution containing a polymer dispersant according to a specific ratio, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0010] Furthermore, in step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 7% to 12%; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 60 to 70° C.; and the particle size of the crushed straw is 80 to 100 meshes.
[0011] Furthermore, in step three, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 5%~8%; the temperature of the ultrasonic field is 85~90°C, the ultrasonic frequency is 50~80 kHz, and the ultrasonic dispersion time is 40-45 minutes; the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is 40~60 microns.
[0012] Furthermore, in step 4, the dispersion ratio of the straw powder and the multi-micron composite wear-resistant filler in the aqueous solution containing the polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 5%~6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 55~65°C, the ultrasonic frequency is 50~80 kHz, and the ultrasonic dispersion time is 30-35 minutes.
[0013] Furthermore, in step 4, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0014] Working principle of the present invention:
[0015] The present invention focuses on the preparation of a friction and wear resistant rape straw / polyvinyl chloride wood plastic composite material. Through the synergistic effect of each step, the friction and wear resistant rape straw / polyvinyl chloride wood plastic composite material prepared can give full play to the resource advantages of rape straw and effectively improve the wear resistance and overall performance of the composite material. The working principle of each step is further described as follows: Low-temperature crushing of rapeseed straw and removal of medullary components: The low temperature makes the material of the straw medullary core brittle, making it easier to break the straw into more regular fragments but not completely crushed. It is beneficial to use the difference in density between the phloem part and the medullary core part of rapeseed straw to separate the medullary core and the phloem part through a pneumatic flotation machine, and then heat and soak in a mixed solution of sodium sulfite and hydrogen peroxide. The synergistic effect of the two can dissolve or decompose lignin, hemicellulose and other components in the medullary core, thereby achieving the purpose of removing residual medullary core and completing the fiber surface modification of the phloem part.
[0016] Preparation of multi-component composite wear-resistant filler: Nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a specific mass ratio. Nano silicon carbide has high hardness and can enhance the wear resistance of the material; nano titanium dioxide has stable chemical properties and can improve the anti-aging performance of the material; graphene oxide has good mechanical properties and barrier properties. In the dispersion containing polymer dispersant, ultrasonic field is used for dispersion. The high-frequency vibration of ultrasound can break the agglomeration between filler particles and make them evenly dispersed in the dispersion. After drying, high-energy ball milling is used to obtain micron-level multi-component wear-resistant filler. The ball milling process further refines the particles and makes the components more evenly mixed at the microscopic level, giving full play to the synergistic enhancement effect of each component.
[0017] Preparation of support filler: The straw powder and multi-component micron composite wear-resistant filler are dispersed and blended in proportion by ultrasonic assisted mixing. The role of ultrasound is to promote the uniform dispersion of the straw powder and the multi-component micron composite wear-resistant filler in the aqueous solution, avoid agglomeration, and make the two fully contact. After spray drying, the support filler powder is obtained. In the powder, the straw powder is used as a support, and the multi-component micron composite wear-resistant filler is evenly loaded, laying the foundation for the subsequent compounding with PVC.
[0018] The beneficial effects of the present invention are:
[0019] By low-temperature crushing of rape straw, the damage to the fiber structure is reduced while effectively crushing it, laying the foundation for subsequent processing and compounding. By combining pneumatic flotation and chemical immersion, the pith is efficiently removed, the quality of straw raw materials is improved, and the overall performance of the composite material is enhanced. Through reasonable component ratios and preparation processes, the friction and wear resistance of the composite material is significantly improved, and its application field is broadened. The preparation of the carrier filler allows the wear-resistant filler to be fully combined with the straw powder, which is conducive to uniform dispersion in the composite material, further improving the performance of the composite material. The preparation method is simple and feasible, with relatively low cost, and realizes the resource utilization of rape straw, with good economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 The wear and physical and mechanical properties test results of Examples 1 to 3 and Comparative Examples 1 to 3; Figure 2 The microscopic morphology of the impact fracture surface and the worn surface of the composite material of Example 1; Figure 3 The microscopic morphology of the impact fracture surface and the worn surface of the composite material of Example 2; Figure 4 The microscopic morphology of the impact fracture surface and the worn surface of the composite material of Example 3; Figure 5 The microscopic morphology of the impact fracture and wear surface of the composite material in Example 1 is shown; Figure 6The microscopic morphology of the impact fracture and wear surface of the composite material in Example 2 is shown; Figure 7 The microscopic morphology of the impact fracture surface and the worn surface of the composite material of Example 3 is shown. DETAILED DESCRIPTION Example 1
[0021] A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry and cut the rapeseed straw into sections, and then use a crusher to preliminarily crush it in a dry and low-temperature environment of -15°C; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 4: Preparation of support filler: Disperse the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a water solution containing a polymer dispersant according to a specific ratio, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0022] Furthermore, in step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 9%; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 65° C.; and the particle size of the crushed straw is 100 mesh.
[0023] Furthermore, in step three, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 6%; the temperature of the ultrasonic field is 85°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 45 minutes; and the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is less than 50 microns.
[0024] Furthermore, in step 4, the dispersion ratio of the straw powder and the multi-component micron composite wear-resistant filler in the aqueous solution containing the polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 60°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 30 minutes.
[0025] Furthermore, in step five, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0026] The physical, mechanical and friction and wear properties test results of the prepared friction and wear resistant rape straw / polyvinyl chloride composite material are as follows: Figure 1 As shown in the figure, the microscopic morphology of the material cross section and the microscopic morphology of the wear surface are as follows: Figure 2 shown. Example 2
[0027] A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry and cut the rapeseed straw into sections, and then use a crusher to preliminarily crush it in a dry and low-temperature environment of -15°C; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 4: Preparation of support filler: Disperse the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a water solution containing a polymer dispersant according to a specific ratio, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0028] Furthermore, in step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 10%; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 60° C.; and the particle size of the crushed straw is 90 mesh.
[0029] Furthermore, in step three, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 6%; the temperature of the ultrasonic field is 85°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 45 minutes; and the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is less than 50 microns.
[0030] Furthermore, in step 4, the dispersion ratio of the straw powder and the multi-component micron composite wear-resistant filler in the aqueous solution containing the polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 55°C, the ultrasonic frequency is 50 kHz, and the ultrasonic dispersion time is 30 minutes.
[0031] Furthermore, in step five, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0032] The physical, mechanical and friction and wear properties test results of the prepared friction and wear resistant rape straw / polyvinyl chloride composite material are as follows: Figure 1 As shown in the figure, the microscopic morphology of the material cross section and the microscopic morphology of the wear surface are as follows: Figure 3 shown. Example 3
[0033] A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry and cut the rapeseed straw into sections, and then use a crusher to preliminarily crush it in a dry and low-temperature environment of -15°C; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 4: Preparation of support filler: Disperse the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a water solution containing a polymer dispersant according to a specific ratio, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0034] Furthermore, in step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 12%; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 70° C.; and the particle size of the crushed straw is 80 meshes.
[0035] Furthermore, in step three, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 6%; the temperature of the ultrasonic field is 85°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 40 minutes; and the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is less than 50 microns.
[0036] Furthermore, in step 4, the dispersion ratio of the straw powder and the multi-micron composite wear-resistant filler in the aqueous solution containing the polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 65°C, the ultrasonic frequency is 80 kHz, and the ultrasonic dispersion time is 35 minutes.
[0037] Furthermore, in step five, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0038] The physical, mechanical and friction and wear properties test results of the prepared friction and wear resistant rape straw / polyvinyl chloride composite material are as follows: Figure 1 As shown in the figure, the microscopic morphology of the material cross section and the microscopic morphology of the wear surface are as follows: Figure 4 shown. Comparative Example 1
[0039] A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: washing, drying, cutting and crushing the rape straw to obtain rape straw powder; Step 2, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 3: Preparation of support filler: Disperse the straw powder obtained in step 1 and the multi-component micron composite wear-resistant filler obtained in step 2 in a specific ratio into an aqueous solution containing a polymer dispersant, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 4: Preparation of composite materials: The support filler powder obtained in step 3 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0040] Furthermore, in step 1, the particle size of the straw after crushing is 100 mesh.
[0041] Furthermore, in step 2, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 6%; the temperature of the ultrasonic field is 85°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 45 minutes; and the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is less than 50 microns.
[0042] Furthermore, in step three, the dispersion ratio of straw powder and multi-micron composite wear-resistant filler in the aqueous solution containing polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 60°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 30 minutes.
[0043] Furthermore, in step 4, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0044] The physical, mechanical and friction and wear properties test results of the prepared friction and wear resistant rape straw / polyvinyl chloride composite material are as follows: Figure 1 As shown in the figure, the microscopic morphology of the material cross section and the microscopic morphology of the wear surface are as follows: Figure 5 shown. Comparative Example 2
[0045] A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry and cut the rapeseed straw into sections, and then use a crusher to preliminarily crush it in a dry and low-temperature environment of -15°C; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3: Mix nano silicon carbide, nano titanium dioxide and graphene oxide in a specific ratio to obtain a mixed multi-component micron composite wear-resistant filler; Step 4: Preparation of support filler: Disperse the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a water solution containing a polymer dispersant according to a specific ratio, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0046] Furthermore, in step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 9; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 65° C.; and the particle size of the crushed straw is 100 mesh.
[0047] Furthermore, in step three, the mixing ratio of nano silicon carbide, nano titanium dioxide and graphene oxide is 10:5:3 by mass, and the mixing is three-dimensional blending.
[0048] Furthermore, in step 4, the dispersion ratio of the straw powder and the multi-component micron composite wear-resistant filler in the aqueous solution containing the polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 60°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 30 minutes.
[0049] Furthermore, in step five, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0050] The physical, mechanical and friction and wear properties test results of the prepared friction and wear resistant rape straw / polyvinyl chloride composite material are as follows: Figure 1 As shown in the figure, the microscopic morphology of the material cross section and the microscopic morphology of the wear surface are as follows: Figure 6 shown. Comparative Example 3
[0051] A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized by comprising the following steps: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry and cut the rapeseed straw into sections, and then use a crusher to preliminarily crush it in a dry and low-temperature environment of -15°C; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 4: Preparation of support filler: blending the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a specific ratio to obtain a support filler; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
[0052] Furthermore, in step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 9; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 65° C.; and the particle size of the crushed straw is 100 mesh.
[0053] Furthermore, in step three, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 6%; the temperature of the ultrasonic field is 85°C, the ultrasonic frequency is 70 kHz, and the ultrasonic dispersion time is 45 minutes; and the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is less than 50 microns.
[0054] Furthermore, in step 4, the ratio of the straw powder to the multi-component micron composite wear-resistant filler is 1:1 by mass.
[0055] Furthermore, in step five, the mass ratio of the support powder, PVC, coupling agent, and stabilizer is 100:100:3:6; the PVC, coupling agent, and stabilizer used are all powders with a particle size of less than 80 mesh.
[0056] The physical, mechanical and friction and wear properties test results of the prepared friction and wear resistant rape straw / polyvinyl chloride composite material are as follows: Figure 1 As shown in the figure, the microscopic morphology of the material cross section and the microscopic morphology of the wear surface are as follows: Figure 7 shown.
[0057] To better illustrate the present invention, the wear-resistant rape straw / polyvinyl chloride wood-plastic composite materials obtained in Examples 1 to 3 and the rape straw / polyvinyl chloride wood-plastic composite materials obtained in Comparative Examples 1 to 3 were tested for physical, mechanical and friction and wear properties using standard testing methods in the industry. The test results are shown in the figure. Figure 1 shown.
[0058] Depend on Figure 1 It can be seen that the composite material prepared by the technical method of the present invention has a lower specific wear rate, significantly enhanced physical and mechanical properties, and significantly improved friction and wear resistance.
[0059] Depend on Figures 2 to 4 It can be seen that the impact cross section of the composite material prepared by the technical method of the present invention shows that the internal structure of the composite material is dense, the straw is tightly combined with the matrix, the wear surface is smooth and flat, and the material removal caused by wear is small; Figures 5 to 7The impact cross section of the composite material in the control group showed that there were many weak bonding surfaces inside the composite material, obvious fiber pull-out and holes, rough wear surface, messy surface texture, and much material removal.
[0060] The present invention provides a method for preparing wear-resistant rape straw / polyvinyl chloride wood-plastic composite materials by combining a process for separating and pretreating components of rape straw with a preparation process of a multi-component micron wear-resistant filler, thus providing a new method for enhancing the friction and wear resistance of the wood-plastic composite materials.
[0061] The above embodiments of the present invention are only examples for explaining the present invention, and are not intended to limit the specific implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above examples. It is impossible to give detailed examples of all implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.
Claims
1. A method for preparing a friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material, characterized in that The following steps are involved: Step 1: Low-temperature crushing of rapeseed straw: Wash, dry, cut the rapeseed straw into sections, and then preliminarily crush it in a dry and low-temperature environment at -10℃~-20℃; Step 2, removing the pith components of rape straw: using a pneumatic flotation machine to float the crushed rape straw fragments obtained in step 1, and then heating and soaking the obtained bast part of the rape straw in a mixed solution of sodium sulfite and hydrogen peroxide, removing the residual pith, and then washing to neutrality, and then drying and crushing; Step 3, preparation of multi-component composite wear-resistant filler: nano silicon carbide, nano titanium dioxide and graphene oxide are mixed in a dispersion containing a polymer dispersant according to a specific ratio, dispersed in an ultrasonic field and then dried, and then crushed by high-energy ball milling to obtain a micron-sized multi-component wear-resistant filler; Step 4: Preparation of support filler: Disperse the straw powder obtained in step 2 and the multi-component micron composite wear-resistant filler obtained in step 3 in a water solution containing a polymer dispersant according to a specific ratio, disperse and blend with the aid of ultrasonic wave, and then spray dry to obtain support filler powder; Step 5: Preparation of composite materials: The support filler powder obtained in step 4 is blended with PVC, a coupling agent and a stabilizer, and then extruded using an extrusion molding technology to prepare a composite material.
2. The method for preparing the friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material according to claim 1, characterized in that: In step 2, the concentration of the mixed solution of sodium sulfite and hydrogen peroxide is 7% to 12%; the volume ratio is 3:1; the temperature of the mixed solution of sodium sulfite and hydrogen peroxide during soaking is 60 to 70° C.; the particle size of the crushed straw is 80 to 100 meshes.
3. The method for preparing the friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material according to claim 1, characterized in that: In step three, the mixing ratio of nano-silicon carbide, nano-titanium dioxide and graphene oxide is 10:5:3 by mass; the concentration of the aqueous solution of the polymer dispersant is 5%~8%; the temperature of the ultrasonic field is 85~90°C, the ultrasonic frequency is 50~80kHz, and the ultrasonic dispersion time is 40-45 minutes; the particle size of the multi-component composite wear-resistant filler after high-energy ball milling is 40~60 microns.
4. The method for preparing the friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material according to claim 1, characterized in that: In step 4, the dispersion ratio of straw powder and multi-micron composite wear-resistant filler in the aqueous solution containing polymer dispersant is 1g:1g:4ml; the concentration of the aqueous solution of the polymer dispersant is 5%~6%; the ultrasonic temperature during ultrasonic-assisted dispersion is 55~65℃, the ultrasonic frequency is 50~80 kHz, and the ultrasonic dispersion time is 30-35 minutes.
5. The method for preparing the friction and wear resistant rape straw / polyvinyl chloride wood-plastic composite material according to claim 1, characterized in that: In step 4, the mass ratio of the support powder, PVC, coupling agent and stabilizer is 100:100:3:6; the PVC, coupling agent and stabilizer used are all powders with a particle size of less than 80 mesh.