PVC (polyvinyl chloride) wood-plastic material with high weather resistance and preparation method of PVC wood-plastic material

Abstract

The invention provides a high-weather-resistance PVC wood-plastic material and a preparation method thereof, and relates to the technical field of wood-plastic composites, the high-weather-resistance PVC wood-plastic material comprises the following materials by weight: 90-120 parts of PVC resin, 30-50 parts of wood flour, 10-30 parts of calcium carbonate, 10-20 parts of weather-resistant master batch, 5-10 parts of a stabilizer, 2-5 parts of a foaming agent, 1-3 parts of a coupling agent, and 1-4 parts of a lubricant; the weather-resistant master batch comprises a core layer, a middle layer and a shell layer, the core layer is titanium oxide, the shell layer is an ultraviolet light absorber, and the middle layer is a compatibilizing material. The technical core point of the invention lies in the design and use of the weather-resistant master batch, so that the weather resistance of the PVC wood-plastic material system is obviously enhanced, and the weather-resistant effect can be exerted for a long time.

Description

Technical Field

[0001] The invention relates to the technical field of wood-plastic composite materials, and in particular to a PVC wood-plastic material with strong weather resistance and a preparation method thereof. Background Art

[0002] Wood-plastic composite materials are a new type of composite material made of wood as the main raw material, which is properly treated to mix it with various plastics (mainly polyvinyl chloride, polyethylene, polypropylene, polystyrene, methyl methacrylate) in a certain proportion and add additives such as coupling agents, dispersants, plasticizers, lubricants, colorants, mildew inhibitors, etc., and is made through high temperature, extrusion, molding and other processes. It is a high-performance, high-value-added green and environmentally friendly composite material with a wide range of uses, green and environmentally friendly, and has broad development prospects. PVC wood-plastic material is the main type of wood-plastic composite material, that is, a composite material made by processing polyvinyl chloride (PVC) and plant fiber materials (usually wood powder).

[0003] PVC wood-plastic materials can be used in various panels, such as wall panels, floors and other home furnishing fields. The weather resistance requirements of PVC wood-plastic materials used in the home field, especially outdoor home furnishings, are relatively high. The weather resistance of PVC wood-plastic materials usually refers to the ability to resist damage from natural environments such as ultraviolet rays, humidity, high temperature and extreme weather. If the weather resistance is poor, the panels are prone to fading, corrosion, cracking and other problems, which seriously affect the service life of the panels.

[0004] Based on this, the present invention discloses a wood-plastic material with strong weather resistance and a preparation method thereof, which improves the weather resistance of the PVC wood-plastic material and enhances its advantage in being applied in the field of outdoor furniture. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides a PVC wood-plastic material with strong weather resistance and a preparation method thereof, which solves the technical problem that the prior PVC wood-plastic material has poor weather resistance.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] The weather-resistant PVC wood-plastic material includes the following materials in parts by weight: 90-120 parts of PVC resin, 30-50 parts of wood powder, 10-30 parts of calcium carbonate, 10-20 parts of weather-resistant masterbatch, 5-10 parts of stabilizer, 2-5 parts of foaming agent, 1-3 parts of coupling agent, and 1-4 parts of lubricant;

[0010] The weather-resistant masterbatch comprises a core layer, an intermediate layer and a shell layer, the core layer is titanium oxide, the shell layer is an ultraviolet absorber, and the intermediate layer is a compatibilizing material.

[0011] Preferably, the mass ratio of the shell layer, the intermediate layer and the core layer is 1:(0.3-0.6):(5-8).

[0012] Preferably, the particle size of the weather-resistant masterbatch is 10-30 μm.

[0013] Preferably, the ultraviolet absorber includes EV75, UV5411 and UV91 in a mass ratio of 1:(1-1.5):(2-3).

[0014] Preferably, the compatibilizing material of the intermediate layer is maleic anhydride grafted polylactic acid.

[0015] Preferably, the preparation method of the maleic anhydride grafted polylactic acid is:

[0016] Maleic anhydride and benzoyl peroxide are dissolved in acetone solution, then evenly mixed with polylactic acid and Sunobo, melt grafted after volatilization, extruded, cooled, crushed and dried to obtain the grafted product maleic anhydride grafted polylactic acid.

[0017] Preferably, the mixing temperature during the grafting of maleic anhydride to polylactic acid is 160-170° C., the rotation speed is 30-35 r / min, and the grafting time is 9-11 min.

[0018] Preferably, when maleic anhydride is grafted onto polylactic acid, the amount of maleic anhydride used is 3-5% of the polylactic acid, and the amount of Surnobo used is 1.5-3% of the polylactic acid.

[0019] Preferably, the stabilizer is an organotin stabilizer.

[0020] Preferably, the blowing agent is azodicarbonamide.

[0021] Preferably, the coupling agent is titanate.

[0022] Preferably, the lubricant is paraffin.

[0023] The preparation method of the weather-resistant PVC wood-plastic material specifically comprises the following steps:

[0024] S1. Screening wood powder with a particle size of 120-150 mesh, drying the wood powder, mixing it evenly with PVC resin, calcium carbonate, lubricant, and weathering masterbatch, then adding stabilizer, foaming agent, coupling agent, and taking out the materials after mixing evenly, adding them to the extruder for granulation, and extruding them into sheets after granulation is completed;

[0025] S2. coating a weather-resistant water-based coating on the surface of the sheet, and drying the coating after the coating surface is left to dry to obtain a finished product.

[0026] Preferably, in S1, the temperature range of each zone of the extruder barrel and the die head is 140-180°C; a single-screw extruder is used to prepare the sheet, and the temperature of each zone of the single screw is 120°C, 130°C, 155°C, 170°C, 180°C, and the rotation speed is 12r / min.

[0027] Preferably, the weather-resistant water-based coating in S2 is V (Sunobo): V (acrylic emulsion) = 1: (80-100).

[0028] (III) Beneficial effects

[0029] The present invention provides a PVC wood-plastic material with strong weather resistance and a preparation method thereof. Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention adds weather-resistant masterbatch to the PVC wood-plastic material formula system, and the weather-resistant masterbatch includes a core layer titanium oxide material, an intermediate layer volume-increasing material, and a shell layer ultraviolet absorber material. The shell layer material is mainly used to resist the damage of ultraviolet rays while ensuring the mechanical properties of the system; the intermediate layer mainly has two functions: one is to provide interface volume-increasing for the core layer and the shell layer materials to improve the compatibility of the core layer and the shell layer materials, thereby improving the overall stability of the weather-resistant masterbatch, and the other function is to further improve the weather resistance of the weather-resistant masterbatch; the core layer material titanium oxide has excellent weather resistance, and when the shell layer and the intermediate layer are eroded by light or humidity, the core layer material can continue to play a weather-resistant role.

[0031] 2. The design and use of the weather-resistant masterbatch of the present invention significantly enhances the weather resistance of the PVC wood-plastic material system and can exert the weather resistance effect for a long time.

[0032] 3. The preparation method of the present invention is simple and can be industrialized. After the PVC wood-plastic sheet is prepared, a layer of weather-resistant coating is coated on the surface thereof to further improve the weather resistance of the PVC wood-plastic material. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The embodiment of the present application solves the technical problem of poor weather resistance of existing PVC wood-plastic materials by providing a PVC wood-plastic material with strong weather resistance and a preparation method thereof.

[0035] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with specific implementation methods.

[0036] The raw materials used in the technical solution disclosed in the present invention are all purchased from cooperative manufacturers.

[0037] Embodiment 1:

[0038] The weather-resistant PVC wood-plastic material comprises the following materials in parts by weight: 90 parts of PVC resin, 30 parts of wood flour, 10 parts of calcium carbonate, 10 parts of weather-resistant masterbatch with a particle size of 10-30 μm, 5 parts of organic tin stabilizer, 2 parts of azodicarbonamide, 1 part of titanate, and 1 part of paraffin;

[0039] The specific composition of weather-resistant masterbatch is shown in the following table:

[0040]

[0041] The preparation method of the middle layer maleic anhydride grafted polylactic acid is as follows:

[0042] Dissolve maleic anhydride and benzoyl peroxide in acetone solution, then mix them with polylactic acid and Sunobao VX-597 evenly, the mixing temperature is 160℃, the rotation speed is 30r / min, the grafting time is 11min, and melt grafting is carried out after volatilization. After extrusion, it is cooled, crushed and dried to obtain maleic anhydride grafted polylactic acid; among them, the maleic anhydride material is 3% of the polylactic acid, and the Sunobao material is 1.5% of the polylactic acid.

[0043] The preparation method of the weather-resistant PVC wood-plastic material specifically comprises the following steps:

[0044] S1. Screen the wood powder with a particle size of 120-150 mesh, dry the wood powder, mix it evenly with PVC resin, calcium carbonate, paraffin, and weather-resistant masterbatch, then add organic tin stabilizer, azodicarbonamide, and titanate. After the materials are evenly mixed, take them out and add them to the extruder for granulation. The temperature range of each zone of the extruder barrel and the die head is 140-180°C;

[0045] After granulation, a single screw extruder is used to extrude into sheets. The temperatures of each zone of the single screw are 120°C, 130°C, 155°C, 170°C, and 180°C, and the speed is 12r / min;

[0046] S2. Apply a weather-resistant water-based coating with a ratio of V (Sunobao VX-597): V (acrylic emulsion) = 1:80 on the surface of the sheet, let it stand until the surface of the coating becomes dry, and then dry it to obtain a finished product.

[0047] Embodiment 2:

[0048] A PVC wood-plastic material with strong weather resistance, comprising the following materials in parts by weight: 100 parts of PVC resin, 40 parts of wood flour, 20 parts of calcium carbonate, 15 parts of weather-resistant masterbatch with a particle size of 10-30 μm, 7 parts of organic tin stabilizer, 4 parts of azodicarbonamide, 2 parts of titanate, and 3 parts of paraffin;

[0049] The specific composition of weather-resistant masterbatch is shown in the following table:

[0050]

[0051] The preparation method of the middle layer maleic anhydride grafted polylactic acid is as follows:

[0052] Dissolve maleic anhydride and benzoyl peroxide in acetone solution, then evenly mix with polylactic acid and Sunopol VX-597, the mixing temperature is 170°C, the rotation speed is 35r / min, the grafting time is 10min, and melt grafting is performed after volatilization. After extrusion, it is cooled, crushed and dried to obtain maleic anhydride grafted polylactic acid; wherein, the maleic anhydride material is 4% of the polylactic acid, and the Sunopol material is 2.5% of the polylactic acid.

[0053] The preparation method of the weather-resistant PVC wood-plastic material specifically comprises the following steps:

[0054] S1. Screen the wood powder with a particle size of 120-150 mesh, dry the wood powder, mix it evenly with PVC resin, calcium carbonate, paraffin, and weather-resistant masterbatch, then add organic tin stabilizer, azodicarbonamide, and titanate. After the materials are evenly mixed, take them out and add them to the extruder for granulation. The temperature range of each zone of the extruder barrel and the die head is 140-180°C;

[0055] After granulation, a single screw extruder is used to extrude into sheets. The temperatures of each zone of the single screw are 120°C, 130°C, 155°C, 170°C, and 180°C, and the speed is 12r / min;

[0056] S2. Apply a weather-resistant water-based coating with a ratio of V (Sunobao VX-597): V (acrylic emulsion) = 1:90 on the surface of the sheet, let it stand until the surface of the coating becomes dry, and then dry it to obtain a finished product.

[0057] Example 3

[0058] The weather-resistant PVC wood-plastic material comprises the following materials in parts by weight: 120 parts of PVC resin, 50 parts of wood powder, 30 parts of calcium carbonate, 20 parts of weather-resistant masterbatch with a particle size of 10-30 μm, 10 parts of organic tin stabilizer, 5 parts of azodicarbonamide, 3 parts of titanate, and 4 parts of paraffin;

[0059] The specific composition of weather-resistant masterbatch is shown in the following table:

[0060]

[0061] The preparation method of the middle layer maleic anhydride grafted polylactic acid is as follows:

[0062] Dissolve maleic anhydride and benzoyl peroxide in acetone solution, then mix them with polylactic acid and Sunobao VX-597 evenly, the mixing temperature is 170℃, the rotation speed is 35r / min, the grafting time is 9min, and melt grafting is carried out after volatilization. After extrusion, it is cooled, crushed and dried to obtain maleic anhydride grafted polylactic acid; wherein, the maleic anhydride material is 5% of the polylactic acid, and the Sunobao material is 3% of the polylactic acid.

[0063] The preparation method of the weather-resistant PVC wood-plastic material specifically comprises the following steps:

[0064] S1. Screen the wood powder with a particle size of 120-150 mesh, dry the wood powder, mix it evenly with PVC resin, calcium carbonate, paraffin, and weather-resistant masterbatch, then add organic tin stabilizer, azodicarbonamide, and titanate. After the materials are evenly mixed, take them out and add them to the extruder for granulation. The temperature range of each zone of the extruder barrel and the die head is 140-180°C;

[0065] After granulation, a single screw extruder is used to extrude into sheets. The temperatures of each zone of the single screw are 120°C, 130°C, 155°C, 170°C, and 180°C, and the speed is 12r / min;

[0066] S2. Apply a weather-resistant water-based coating with a ratio of V (Sunobao VX-597): V (acrylic emulsion) = 1:100 on the surface of the sheet, let it stand until the surface of the coating becomes dry, and then dry it to obtain a finished product.

[0067] Comparative Example 1 is different from Example 2 in that:

[0068] Remove weather-resistant masterbatch from PVC wood-plastic material system.

[0069] Comparative Example 2 is different from Example 2 in that:

[0070] The weather-resistant masterbatch only includes the core layer titanium oxide and the shell layer ultraviolet absorber, and does not include the intermediate layer. The difference between Comparative Example 3 and Example 2 is that:

[0071] When preparing maleic anhydride grafted polylactic acid, no Sunobao VX-597 is added.

[0072] Comparative Example 4 is different from Example 2 in that:

[0073] When preparing the intermediate layer material, the polylactic acid is not grafted and modified.

[0074] Comparative Example 5 is different from Example 2 in that:

[0075] When preparing the intermediate layer material, polylactic acid was grafted and modified using methacrylate hydroglycerol. The difference between Comparative Example 6 and Example 2 is that:

[0076] The mass ratio of the shell layer, middle layer and core layer of the weather-resistant masterbatch is 1:0.2:5.

[0077] Comparative Example 7 is different from Example 2 in that:

[0078] The mass ratio of the shell layer, middle layer and core layer of the weather-resistant masterbatch is 1:0.45:9.

[0079] Comparative Example 8 is different from Example 2 in that:

[0080] Delete EV75 in the UV absorber.

[0081] Comparative Example 9 is different from Example 2 in that:

[0082] Delete UV91 in UV absorber.

[0083] Comparative Example 10 is different from Example 2 in that:

[0084] Delete UV5411 in UV absorber.

[0085] Comparative Example 11 is different from Example 2 in that:

[0086] Use UV151 instead of EV75.

[0087] Comparative Example 12 is different from Example 2 in that:

[0088] Use UV3529 instead of UV91.

[0089] Comparative Example 13 is different from Example 2 in that:

[0090] Use UV326 instead of UV5411.

[0091] Comparative Example 14 is different from Example 2 in that:

[0092] Use UV151 instead of EV75 and UV3529 instead of UV91.

[0093] Comparative Example 15 is different from Example 2 in that:

[0094] The mass ratio of EV75, UV5411 and UV91 is 1:0.5:2.

[0095] Comparative Example 16 is different from Example 2 in that:

[0096] The mass ratio of EV75, UV5411, and UV91 is 1:1.25:1.

[0097] Comparative Example 17 is different from Example 2 in that:

[0098] The mass ratio of EV75, UV5411 and UV91 is 1:1.25:4.

[0099] Performance test data

[0100] The high heat-resistant PVC wood-plastic composite materials and the preparation methods thereof prepared by the methods of Examples 1-3 and Comparative Examples 1-17 were sampled, and the following performance tests were performed on each group of samples.

[0101] The samples were subjected to UV aging tests using a Q-Sun air-cooled xenon lamp, with reference to the relevant provisions of ASTM G155-05a, through 102 minutes of light exposure, 18 minutes of light exposure + spraying, with an irradiation intensity of 0.35W / m2@340nm and a temperature setting of 63±2℃, and a cycle of 2000 hours.

[0102] 1. Color difference △E measurement

[0103] Color difference △E is one of the important means to measure the color change of the material before and after aging. According to GB / T7921-2008, the SC-80C fully automatic colorimeter and the Konica Minolta CM-2600d spectrophotometer were used to test the color difference △E of the samples before and after aging. Each sample was tested 6 times at different positions, and the average value was taken. The test results are recorded in Table 1.

[0104] 2. Determination of flexural strength retention rate

[0105] According to GB / T 9341-2008, the bending strength of the sample before and after UV aging was measured, and the bending strength retention rate was calculated to characterize the weather resistance of the sample. The test results are recorded in Table 1.

[0106] Table 1-Related test data of samples

[0107]

[0108]

[0109] From the data in Table 1, we can see that:

[0110] 1. The sample experimental data of Examples 1-3 show that the PVC wood-plastic material prepared by the technical solution of the present invention has excellent weather resistance.

[0111] 2. The sample experimental data of Example 2 and Comparative Example 1 show that the key technical point of the present invention is the addition of weather-resistant masterbatch, and the weather-resistant masterbatch has a great influence on the weather resistance of the PVC wood-plastic material system.

[0112] 3. The experimental data of the samples of Example 2 and Comparative Examples 2-5 show that the maleic anhydride grafted polylactic acid in the middle layer of the weather-resistant masterbatch has an excellent effect in improving weather resistance. This may be because the maleic anhydride grafted polylactic acid itself has a volume-increasing effect, which can make the core layer and the shell layer of the weather-resistant masterbatch tightly connected, thereby improving the overall stability of the weather-resistant masterbatch. In addition, Sunobao VX-597 is also added to the middle layer, which is beneficial to further improve the weather resistance of the weather-resistant masterbatch.

[0113] 4. The experimental data of the samples of Example 2 and Comparative Examples 6-7 show that the weather resistance performance of the weather resistance masterbatch can be maximized by controlling the mass ratio of the shell layer, the middle layer and the core layer of the weather resistance masterbatch within an appropriate range.

[0114] 5. The experimental data of the samples of Example 2 and Comparative Examples 8-14 show that there is a synergistic effect between the three components of EV75, UV5411, and UV91. This may be because EV75 and UV5411 are both benzotriazole light stabilizers with excellent ultraviolet absorption performance, and the free radical capture effect of UV91 hindered amine light stabilizer can synergistically enhance the material's anti-light aging performance. Moreover, when these three components are replaced by other light stabilizers with similar effects, the anti-light aging effect is also excellent, but it cannot reach the effect when these three components act together.

[0115] 6. The experimental data of the samples of Example 2 and Comparative Examples 15-17 show that the ratio between the three components of EV75, UV5411 and UV91 will also affect the overall weather resistance of the system. Therefore, the ratio needs to be controlled within an appropriate range to fully exert the effectiveness of the synergistic components.

[0116] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0117] 1. The present invention adds weather-resistant masterbatch to the PVC wood-plastic material formula system, and the weather-resistant masterbatch includes a core layer titanium oxide material, an intermediate layer volume-increasing material, and a shell layer ultraviolet absorber material. The shell layer material is mainly used to resist the damage of ultraviolet rays while ensuring the mechanical properties of the system; the intermediate layer mainly has two functions: one is to provide interface volume-increasing for the core layer and the shell layer materials to improve the compatibility of the core layer and the shell layer materials, thereby improving the overall stability of the weather-resistant masterbatch, and the other function is to further improve the weather resistance of the weather-resistant masterbatch; the core layer material titanium oxide has excellent weather resistance, and when the shell layer and the intermediate layer are eroded by light or humidity, the core layer material can continue to play a weather-resistant role.

[0118] 2. The design and use of the weather-resistant masterbatch of the present invention significantly enhances the weather resistance of the PVC wood-plastic material system and can exert the weather resistance effect for a long time.

[0119] 3. The preparation method of the present invention is simple and can be industrialized. After the PVC wood-plastic sheet is prepared, a layer of weather-resistant coating is coated on the surface thereof to further improve the weather resistance of the PVC wood-plastic material.

[0120] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0121] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A weather-resistant PVC wood-plastic material, characterized in that: The materials include the following parts by weight: 90-120 parts of PVC resin, 30-50 parts of wood flour, 10-30 parts of calcium carbonate, 10-20 parts of weather-resistant masterbatch, 5-10 parts of stabilizer, 2-5 parts of foaming agent, 1-3 parts of coupling agent, and 1-4 parts of lubricant; The weather-resistant masterbatch comprises a core layer, an intermediate layer and a shell layer, the core layer is titanium oxide, the shell layer is an ultraviolet absorber, and the intermediate layer is a compatibilizing material.

2. The weather-resistant PVC wood-plastic material according to claim 1, characterized in that: The mass ratio of the shell layer, the intermediate layer and the core layer is 1:(0.3-0.6):(5-8).

3. The weather-resistant PVC wood-plastic material according to claim 1, characterized in that: The ultraviolet absorber includes EV75, UV5411 and UV91 in a mass ratio of 1:(1-1.5):(2-3).

4. The weather-resistant PVC wood-plastic material according to claim 3, characterized in that: The compatibilizing material of the intermediate layer is maleic anhydride grafted polylactic acid.

5. The weather-resistant PVC wood-plastic material according to claim 4, characterized in that: The preparation method of the maleic anhydride grafted polylactic acid is: Maleic anhydride and benzoyl peroxide are dissolved in acetone solution, then evenly mixed with polylactic acid and Sunobo, melt grafted after volatilization, extruded, cooled, crushed and dried to obtain the grafted product maleic anhydride grafted polylactic acid.

6. The weather-resistant PVC wood-plastic material according to claim 4, characterized in that: The mixing temperature during the grafting of maleic anhydride to polylactic acid is 160-170° C., the rotation speed is 30-35 r / min, and the grafting time is 9-11 min.

7. The weather-resistant PVC wood-plastic material according to claim 1, characterized in that: When maleic anhydride is grafted onto polylactic acid, the amount of maleic anhydride used is 3-5% of the polylactic acid, and the amount of Surnobo used is 1.5-3% of the polylactic acid.

8. The method for preparing the weather-resistant PVC wood-plastic material according to any one of claims 1 to 7, characterized in that: The specific steps include: S1. Screening wood powder with a particle size of 120-150 mesh, drying the wood powder, mixing it evenly with PVC resin, calcium carbonate, lubricant, and weathering masterbatch, then adding stabilizer, foaming agent, coupling agent, and taking out the materials after mixing evenly, adding them to the extruder for granulation, and extruding them into sheets after granulation is completed; S2. coating a weather-resistant water-based coating on the surface of the sheet, allowing the coating to stand for a while until the surface becomes dry, and then drying the coating to obtain a finished product.

9. The method for preparing the weather-resistant PVC wood-plastic material according to claim 8, characterized in that: In S1, the temperature range of each zone of the extruder barrel and the die head is 140-180°C; a single-screw extruder is used to prepare the sheet, and the temperatures of each zone of the single screw are 120°C, 130°C, 155°C, 170°C, and 180°C, and the rotation speed is 12r / min.

10. The method for preparing the weather-resistant PVC wood-plastic material according to claim 8, characterized in that: The weather-resistant water-based coating in S2 is V (Sunobo): V (acrylic emulsion) = 1: (80-100).

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