Preparation method and recycling method of hollow glass bead / PMMA (polymethyl methacrylate) wind power blade core material

Abstract

The invention relates to a preparation method and a recycling method of a hollow glass bead / PMMA (polymethyl methacrylate) wind power blade core material, and belongs to the technical field of high polymer materials. According to the preparation method of the hollow glass bead / PMMA wind power blade core material, firstly, polymethyl methacrylate and an initiator are dissolved in methyl methacrylate, a mixed solution is obtained, the viscosity of the mixed solution is adjustable, hollow glass beads with higher content can be added into the mixed solution, and the hollow glass bead / PMMA wind power blade core material with the density lower than 0.45 g / cm < 3 > is obtained. The prepared hollow glass bead / PMMA wind turbine blade core material can be repeatedly dissolved in a methyl methacrylate monomer, the hollow glass beads and organic materials can be separated through solid-liquid separation after dissolution, then the hollow glass beads and the organic materials are repeatedly utilized, no solid waste is generated, and the method is environmentally friendly. 100% recycling of materials can be achieved, and green and sustainable development of the wind power industry is achieved.

Description

Technical Field

[0001] The present invention relates to a preparation method and a recycling method of hollow glass microsphere / PMMA wind turbine blade core materials, belonging to the technical field of polymer materials. Background Art

[0002] With the rapid growth of the global economy, the demand for energy by humans is also increasing continuously. The rapid development of technology has led to the overconsumption of conventional energy mainly based on coal, oil, and natural gas. The shortage of energy and environmental pollution have become the main problems restricting the economic development of various countries. Only by vigorously developing new energy can sustainable development be achieved. The development and utilization of new energy can not only supplement conventional energy but also effectively reduce environmental pollution. In the process of developing new energy, wind energy has developed rapidly in various countries of the world due to its short construction period, low environmental requirements, rich reserves, and high utilization rate.

[0003] Traditional wind turbine web core materials mainly include PVC foam, PET foam, and balsa wood. A large amount of thermosetting resin needs to be poured when using wind turbine core materials. However, the above wind turbine core materials have the following disadvantages: (1) PVC foam, PET foam, and balsa wood cannot be integrally formed because the strength of PVC foam and PET foam is insufficient, and balsa wood is natural wood with limited dimensions, restricted by the place of production and growth cycle; (2) The use of thermosetting resin results in a large amount of solid waste generated after the retirement of wind turbine blades and cannot be recycled, causing great pollution to the environment. Therefore, it is crucial to develop recyclable wind turbine core materials to achieve the green and sustainable development of the wind power industry.

[0004] Thermoplastic resins can be recycled after use. Therefore, it is an inevitable trend in the development of wind power composites to replace thermosetting resins with thermoplastic resins. Chinese Patent Document CN106700373A discloses a method for preparing a glass microsphere / PMMA composite material. The method is to first pretreat PMMA particles and hollow glass microspheres, and then take 80 - 90 parts of pretreated PMMA and 10 - 20 parts of hollow glass microspheres by weight, add 0.03 - 0.06 parts of ultraviolet absorber, 0.02 - 0.05 parts of antioxidant, and 0.3 - 0.5 parts of demolding agent, and mix them evenly. Finally, use a twin-screw extruder to blend and granulate the mixture to prepare a glass microsphere / PMMA composite material. The method disclosed in this patent document is simple and easy to operate. By introducing hollow glass microspheres to be compounded with PMMA, the hardness and impact resistance of the PMMA material are improved, and it is transparent and has a low cost. However, in the method disclosed in this patent document, the composite material is processed by a twin-screw extruder to mix the molten PMMA resin and hollow glass microspheres. However, the viscosity of the molten PMMA resin is relatively large, and a large amount of hollow glass microspheres cannot be added, resulting in the density of the prepared composite material being above 0.6g / cm 3 3, making it difficult to prepare a hollow glass microsphere / PMMA wind turbine blade core material with a density below 0.45g / cm 3 3. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for preparing a hollow glass microsphere / PMMA wind turbine blade core material to solve the problem that the currently prepared hollow glass microsphere / PMMA wind turbine blade core material has a relatively large density.

[0006] Another purpose of the present invention is to provide a method for recycling a hollow glass microsphere / PMMA wind turbine blade core material to solve the problem that the currently existing wind turbine blade core material cannot be recycled.

[0007] In order to achieve the above purposes, the technical solution adopted by the method for preparing a hollow glass microsphere / PMMA wind turbine blade core material of the present invention is as follows:

[0008] A method for preparing a hollow glass microsphere / PMMA wind turbine blade core material, comprising the following steps: dissolving polymethyl methacrylate and an initiator in methyl methacrylate to obtain a mixed solution, and then mixing the mixed solution with hollow glass microspheres modified by a compatibilizer to obtain a mixture; then curing and molding the mixture to obtain a hollow glass microsphere / PMMA wind turbine blade core material; the weight-average molecular weight of the polymethyl methacrylate is 100,000 - 300,000, and the mass ratio of polymethyl methacrylate to methyl methacrylate is (5 - 30):100, and the density of the hollow glass microsphere / PMMA wind turbine blade core material is less than 0.45g / cm 3。

[0009] The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material of the present invention is to first dissolve polymethyl methacrylate and an initiator in methyl methacrylate to obtain a mixed solution. The viscosity of the mixed solution can be adjusted, and a higher content of hollow glass microspheres can be added to the mixed solution, and then a hollow glass microsphere / PMMA wind turbine blade core material with a density lower than 0.45 g / cm 3 is prepared. The hollow glass microsphere / PMMA wind turbine blade core material prepared by the present invention can be repeatedly dissolved in methyl methacrylate monomer, and after dissolution, the separation of hollow glass microspheres and organic materials can be achieved through solid-liquid separation, and then the hollow glass microspheres and organic materials can be reused, without generating any solid waste, and 100% recycling and reuse of the materials can be realized, thereby achieving the green and sustainable development of the wind power industry.

[0010] Preferably, the compatibilizer is an acrylate sizing agent. The preparation of the acrylate sizing agent includes: mixing butyl acrylate, methyl methacrylate, acrylic acid, an emulsifier and water to obtain a pre-emulsion; then adding the pre-emulsion and an initiator to the bottom liquid for polymerization reaction, adjusting the pH to 7-8, and then adding a thickener and mixing evenly; the bottom liquid is a surfactant solution.

[0011] Further preferably, when preparing the pre-emulsion, the mass ratio of butyl acrylate, methyl methacrylate, acrylic acid, an emulsifier and water is: (60-70):(30-40):(10-15):(3-5):(150-160); the mass concentration of the surfactant solution is 1.5-2%; the mass ratio of the water quality of the pre-emulsion to the mass of the bottom liquid is (150-160):(50-53). More preferably, the pre-emulsion and the initiator are added dropwise to the bottom liquid, and the dropping time is 3-3.5 h; the system temperature is maintained at 78-80 °C during the dropping process, and after the dropping is completed, it is kept warm at 78-80 °C for 1-1.5 h.

[0012] Preferably, the mass ratio of the water quality of the pre-emulsion to the mass of the thickener is (150-160):(1-1.5).

[0013] Preferably, the density of the hollow glass microspheres is 0.1-0.28 g / cm 3 ; the mass ratio of the hollow glass microspheres is not less than 14% of the mass of the hollow glass microsphere / PMMA wind turbine blade core material.

[0014] Preferably, the initiator is a high-temperature initiator or a normal-temperature initiator. The high-temperature initiator is benzoyl peroxide, azobisisobutyronitrile or azobisisoheptonitrile; the normal-temperature initiator is composed of benzoyl peroxide and a promoter, and the promoter is N,N-dimethylacetamide.

[0015] Preferably, the mass of the high-temperature initiator is 1-3% of the total mass of polymethyl methacrylate and methyl methacrylate; the mass of benzoyl peroxide in the room-temperature initiator is 1-2% of the total mass of polymethyl methacrylate and methyl methacrylate, and the mass of the accelerator is 0.1-0.5% of the total mass of polymethyl methacrylate and methyl methacrylate.

[0016] Preferably, the curing and molding is vacuum hot pressing. When vacuum hot pressing, the pressure is 1-1.5 MPa, the temperature is from room temperature to 90 °C, and the time is 6-8 h.

[0017] The technical solution adopted by the recycling method of the hollow glass microsphere / PMMA wind turbine blade core material of the present invention is as follows:

[0018] A recycling method for a hollow glass microsphere / PMMA wind turbine blade core material prepared by the preparation method of a hollow glass microsphere / PMMA wind turbine blade core material as described above, comprising the following steps: crushing the hollow glass microsphere / PMMA wind turbine blade core material and dissolving it in methyl methacrylate, and then performing solid-liquid separation. The solid obtained by solid-liquid separation is hollow glass microspheres, and the liquid obtained by solid-liquid separation is a mixture of polymethyl methacrylate and methyl methacrylate.

[0019] The hollow glass microsphere / PMMA wind turbine blade core material prepared by the present invention can be repeatedly dissolved in methyl methacrylate monomer. After dissolution, the separation of hollow glass microspheres and organic materials can be achieved through solid-liquid separation. Then, the hollow glass microspheres and organic materials can be reused without generating any solid waste, and 100% recycling and reuse of the materials can be realized, thereby achieving the green and sustainable development of the wind power industry. Detailed implementation manners

[0020] The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material of the present invention is a pioneering invention. First, polymethyl methacrylate and an initiator are dissolved in methyl methacrylate to obtain a mixed solution. The viscosity of the mixed solution can be adjusted, and a higher content of hollow glass microspheres can be added to the mixed solution, thereby preparing a hollow glass microsphere / PMMA wind turbine blade core material with a density lower than 0.45 g / cm 3 ³.

[0021] Since hollow glass microspheres are inorganic materials and have poor bonding strength with PMMA resin, in the present invention, the surface of the hollow glass microspheres is treated to form an organic film on the surface of the hollow glass microspheres, enhancing the bonding ability between the microspheres and the PMMA matrix resin, thereby enhancing the mechanical properties of the PMMA wind turbine blade core material. It is preferred to use an acrylate sizing agent to perform compatibilizing modification on the hollow glass microspheres.

[0022] Specifically, the preparation method of the acrylate sizing agent is as follows:

[0023] 1. Pre - emulsification: Mix 60 g of butyl acrylate (BA) monomer, 30 g of methyl methacrylate (MMA), 10 g of acrylic acid (AA), 3 g of emulsifier OP - 10 and 150 g of deionized water, and stir at high speed to form a pre - emulsion.

[0024] 2. Polymerization: Drop the pre - emulsion and 0.5 g of ammonium persulfate (APS) (dissolved in 10 g of water) into the reaction kettle (containing 50 g of deionized water + 1 g of sodium dodecyl sulfate (SDS)) at 80 °C. The dropping is completed in 3 hours, and then keep the temperature for 1 hour. The deionized water and SDS form a bottom liquid with a mass concentration of about 1.9%.

[0025] 3. Post - treatment: Cool down to 40 °C, add ammonia water to adjust the pH to 7 - 8, and finally add 1 g of thickener sodium polyacrylate and stir evenly.

[0026] The modification of hollow glass microspheres can be carried out in the following way: Mix the hollow glass microspheres and acrylate sizing agent, and then filter and dry to obtain the hollow glass microspheres modified by the compatibilizer. Specifically, add the hollow glass microspheres to the acrylate sizing agent. The addition amount of the hollow glass microspheres is based on the sizing agent being able to completely impregnate the hollow glass microspheres. Slowly stir the mixture of the hollow glass microspheres and the sizing agent for 10 - 20 min, then filter to remove the excess sizing agent, dry the filtered hollow glass microspheres, and screen them with a 100 - mesh sieve to obtain the hollow glass microspheres treated with the acrylate sizing agent.

[0027] The technical solutions of the present invention will be further described below in conjunction with specific embodiments.

[0028] I. Specific embodiments of the preparation method of the hollow glass microsphere / PMMA wind turbine blade core material of the present invention

[0029] Example 1

[0030] The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material in this example specifically includes the following steps:

[0031] (1) Crush the polymethyl methacrylate (PMMA) plastic particles into powder, then add the methyl methacrylate (MMA) monomer to the high - speed disperser, add the PMMA powder while stirring, and stir and disperse tightly for 3 h. Wait until all the PMMA powder is dissolved to obtain a liquid PMMA resin solution, whose viscosity at room temperature (25 °C) is 100 mPa·s; the weight - average molecular weight of polymethyl methacrylate is 100,000, the dosage of polymethyl methacrylate powder is 0.5 kg, and the dosage of methyl methacrylate monomer is 10 kg. The viscosity of this liquid PMMA resin solution can be adjusted, generally within the range of 100 - 1,000,000 mPa·s.

[0032] (2) Add 8.35 kg of the liquid PMMA resin solution prepared in step (1) and 240 g of initiator benzoyl peroxide (BPO, accounting for 2.8% of the liquid PMMA resin solution) to the blender, stir evenly until the initiator is completely dissolved, and then add 1.65 kg of hollow glass microspheres with a density of 0.1 g / cm 3 (after modification, the same below; the addition amount is 16.5% of the total mass of the core material) to the blender, continue to stir for 30 min to obtain a mixture, then weigh 10 kg of the mixture and add it to the mold (the mold specification is 25 L) of the vacuum hot press, the clamping pressure is 1 MPa, evacuate and heat up to 90 °C, keep warm and pressurize for 6 h, and open the mold after cooling to obtain hollow glass microsphere / PMMA wind turbine blade core material with a density of 0.4 g / cm 3 that can be used as the core material of wind turbine blades.

[0033] Example 2

[0034] The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material in this example specifically includes the following steps:

[0035] (1) Crush polymethyl methacrylate (PMMA) plastic particles into powders, then add methyl methacrylate (MMA) monomers to a high-speed disperser, add PMMA powders while stirring, close and stir for dispersion for 3 h, wait until all PMMA powders are dissolved to obtain a liquid PMMA resin solution, and the viscosity at room temperature is 1,000,000 mPa·s; the weight-average molecular weight of polymethyl methacrylate is 100,000, the amount of polymethyl methacrylate powder used is 3 kg, and the amount of methyl methacrylate monomer used is 10 kg.

[0036] (2) Add 8.1 kg of the liquid PMMA resin solution prepared in step (1) and 240 g of initiator azobisisobutyronitrile (AIBN, accounting for 2.9%) to the blender, stir evenly until the initiator is completely dissolved, and then add 2.97 kg of hollow glass microspheres with a density of 0.15 g / cm 3 (the addition amount is 26.8% of the total mass of the core material) to the blender, continue to stir for 30 min to obtain a mixture, then weigh 10 kg of the mixture and add it to the mold (the mold specification is 25 L) of the vacuum hot press, the clamping pressure is 1.5 MPa, evacuate and heat up to 90 °C, keep warm and pressurize for 6 h, and open the mold after cooling to obtain hollow glass microsphere / PMMA wind turbine blade core material with a density of 0.4 g / cm 3 that can be used as the core material of wind turbine blades.

[0037] Example 3

[0038] The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material in this example specifically includes the following steps:

[0039] (1) The polymethyl methacrylate (PMMA) plastic particles are crushed into powder, and then methyl methacrylate (MMA) monomer is added to a high-speed disperser. While stirring, the PMMA powder is added, and the mixture is stirred and dispersed in a closed state for 3 h. After all the PMMA powder is dissolved, a liquid PMMA resin solution is obtained, with a viscosity of 100 mPa·s at room temperature; the weight-average molecular weight of polymethyl methacrylate is 300,000, the amount of PMMA powder used is 0.5 kg, and the amount of methyl methacrylate monomer used is 10 kg.

[0040] (2) Add 5.7 kg of the liquid PMMA resin solution prepared in step (1), 57 g of initiator benzoyl peroxide (BPO, accounting for 1%) and 17 g of accelerator N,N-dimethylacetamide (DMA, accounting for 0.3%) to a blender, stir evenly until all the initiator is dissolved, and then add 0.88 kg of hollow glass microspheres with a density of 0.15 g / cm 3 and 4.5 kg of hollow glass microspheres with a density of 0.28 g / cm 3 (the total addition amount is 48.6% of the total mass of the core material) to the blender, continue to stir for 30 min to obtain a mixture. Then weigh 10 kg of the mixture and add it to the mold of a vacuum hot press (the mold specification is 25 L), with a closing pressure of 1.5 MPa, evacuate and heat up to 30 °C, keep warm and under pressure for 6 h, and open the mold after cooling to obtain hollow glass microsphere / PMMA wind turbine blade core material with a density of 0.4 g / cm 3 that can be used as the core material of wind turbine blades.

[0041] Example 4

[0042] The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material in this example specifically includes the following steps:

[0043] (1) The polymethyl methacrylate (PMMA) plastic particles are crushed into powder, and then methyl methacrylate (MMA) monomer is added to a high-speed disperser. While stirring, the PMMA powder is added, and the mixture is stirred and dispersed in a closed state for 3 h. After all the PMMA powder is dissolved, a liquid PMMA resin solution is obtained, with a viscosity of 1,000,000 mPa·s at room temperature; the weight-average molecular weight of polymethyl methacrylate is 300,000, the amount of PMMA powder used is 3 kg, and the amount of methyl methacrylate monomer used is 10 kg.

[0044] (2) Add 5.3 kg of the liquid PMMA resin solution prepared in step (1) and 122 g of initiator BPO (accounting for 2.3%) to a blender, stir evenly until all the initiator is dissolved, and then add 4.7 kg of hollow glass microspheres with a density of 0.28 g / cm 3Hollow glass microspheres (the addition amount is 47.0% of the total mass of the core material), continue to stir for 30 min to obtain a mixture. Then weigh 10 kg of the mixture and add it to the mold (the mold specification is 25 L) of a vacuum hot press. The mold closing pressure is 1 MPa, evacuate and heat up to 90 °C, keep warm and press for 6 h, open the mold after cooling, and obtain a density of 0.4 g / cm 3 Hollow glass microsphere / PMMA wind turbine blade core material that can be used as the core material of wind turbine blades.

[0045] II. Specific embodiments of the recycling method of the hollow glass microsphere / PMMA wind turbine blade core material of the present invention

[0046] Example 5

[0047] The recycling method of the hollow glass microsphere / PMMA wind turbine blade core material in this example includes the following steps: Cut the hollow glass microsphere / PMMA wind turbine blade core material prepared in Example 1 into small pieces to obtain composite material powder. Then soak the composite material powder in MMA monomer and mechanically stir for 24 h until the composite material powder is completely dissolved. Then filter to separate the hollow glass microspheres and the dissolved liquid. The hollow glass microspheres are washed with ethanol 2 - 3 times and can be reused after drying. The separated liquid can also be reused when preparing the PMMA liquid resin solution. Therefore, the hollow glass microsphere / PMMA wind turbine blade core material of the present invention can be recycled and reused without generating solid waste.

[0048] III. Comparative examples

[0049] Comparative example 1

[0050] The recycling method of the hollow glass microsphere / PMMA wind turbine blade core material in this comparative example includes the following steps: Crush polymethyl methacrylate (PMMA) plastic particles into powder. Then add methyl methacrylate (MMA) monomer to a high-speed disperser, add PMMA powder while stirring, and stir and disperse tightly for 3 h until the PMMA powder is completely dissolved to obtain a liquid PMMA resin solution; the weight-average molecular weight of polymethyl methacrylate is 300,000, the dosage of polymethyl methacrylate powder is 4 kg, and the dosage of methyl methacrylate monomer is 10 kg.

[0051] The mass ratio of PMMA resin to MMA monomer is 40:100. The PMMA liquid resin prepared in this way has too high viscosity and is difficult to stir with mechanical stirring, and the hollow glass microspheres cannot be dispersed evenly in it.

[0052] Comparative example 2

[0053] Recycling method of hollow glass microsphere / PMMA wind turbine blade core material in this comparative example includes the following steps: (1) Crushing polymethyl methacrylate (PMMA) plastic particles into powder, adding methyl methacrylate (MMA) monomer into a high-speed disperser, adding PMMA powder while stirring, sealing and stirring for 3 h until all PMMA powder is dissolved to obtain a liquid PMMA resin solution; the weight-average molecular weight of polymethyl methacrylate is 100,000, the dosage of PMMA powder is 3 kg, and the dosage of methyl methacrylate monomer is 10 kg.

[0054] (2) Adding 3.6 kg of the liquid PMMA resin solution prepared in step (1) and 83 g of initiator azobisisobutyronitrile (AIBN) into a blender, stirring evenly until all the initiator is dissolved, then adding 6.4 kg of hollow glass microspheres with a density of 0.3 g / cm 3 into the blender, continuing to stir for 30 min to obtain a mixture, then weighing 10 kg of the mixture, adding it into the mold (mold specification is 25 L) of a vacuum hot press, with a closing pressure of 1.5 MPa, evacuating and heating to 90 °C, maintaining temperature and pressure for 6 h, and opening the mold after cooling to obtain hollow glass microsphere / PMMA wind turbine blade core material with a density of 0.4 g / cm 3 which can be used as the wind turbine blade core material.

[0055] IV. Experimental Examples

[0056] Testing the compressive strength, tensile strength, and shear strength of the hollow glass microsphere / PMMA wind turbine blade core materials prepared in each example under the same conditions according to the provisions of standard ISO 15635:2017 "Determination of Compressive Strength of Rigid Cellular Plastics", standard GB / T 9461-1988 "Test Method for Tensile Properties of Rigid Cellular Plastics", and GB / T 10007-2008 "Test Method for Shear Strength of Rigid Cellular Plastics".

[0057] Existing web core materials use foam materials such as PVC foam. There are many pores on the surface of such materials, and the resin penetrates along the pores into the interior on its surface. Although it increases the strength of the wind turbine web, it also causes a significant increase in its own density. The resin absorption amount reflects the number of pores on the surface of the core material. The more pores on the surface, the greater the resin absorption amount, and the greater the final density of the product. When testing the resin absorption amount, immerse the foam material in the glue for 24 h, then remove the excess glue on the surface of the material, and after the glue cures, weigh the mass of the foam material before and after soaking in the glue to obtain the resin absorption amount.

[0058] The specific test results are shown in Table 1. The density of each material under the core material item in Table 1 is 0.4 g / cm 3 .

[0059] Table 1 Mechanical properties of the hollow glass microsphere / PMMA wind turbine blade core materials prepared in each example

[0060] Core material Compressive strength (MPa) Tensile strength (MPa) Shear strength (MPa) <![CDATA[Adhesive absorption amount (kg / m 2 )]]> Example 1 20.7 15.3 9.8 0 Example 2 21.4 16.1 9.1 0 Example 3 19.7 14.4 8.7 0 Example 4 22.3 15.9 9.6 0 Comparative example 2 7.1 4.8 3.1 0.1 PVC foam 3 1.69 0.8 0.6 PET foam 3 2.3 0.8 0.4 Balsa wood 10 3.9 2 0

[0061] As can be seen from Table 1, the mechanical properties of the PMMA / hollow glass microsphere wind turbine core materials prepared using liquid resin and hollow glass microspheres are superior to those of the commonly used PVC, PET, and balsa wood wind turbine core materials in all aspects. At the same time, the hollow glass microspheres have a closed-cell structure and there is no problem of resin absorption.

[0062] From the comparison between Comparative Example 2 and Examples 1 to 4, it can be seen that for the wind turbine blade core materials prepared using hollow glass microspheres with a density of 0.3 g / cm 3 , the surface is prone to powdering and the mechanical properties decrease significantly. This is because when the density of the hollow glass microspheres is too high, more hollow glass microspheres need to be added to achieve a density of 0.4 g / cm 3 , resulting in a lack of resin in the prepared material, which will in turn affect the performance of the product.

Claims

1. A preparation method of hollow glass microsphere / PMMA wind turbine blade core material, characterized in that, It includes the following steps: Dissolve polymethyl methacrylate and an initiator in methyl methacrylate to obtain a mixed solution, and then mix the mixed solution with hollow glass microspheres modified by a compatibilizer to obtain a mixture; then cure and mold the mixture to obtain a hollow glass microsphere / PMMA wind turbine blade core material; the weight-average molecular weight of the polymethyl methacrylate is 100,000 to 300,000, and the mass ratio of polymethyl methacrylate to methyl methacrylate is (5 to 30):

100. The density of the hollow glass microsphere / PMMA wind turbine blade core material is less than 0.45 g / cm 3 .

2. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 1, characterized in that The compatibilizer is an acrylate sizing agent, and the preparation of the acrylate sizing agent includes: mixing butyl acrylate, methyl methacrylate, acrylic acid, an emulsifier and water to obtain a pre-emulsion; then adding the pre-emulsion and an initiator to a bottom liquid for polymerization reaction, adjusting the pH to 7-8, and then adding a thickener and mixing well; the bottom liquid is a surfactant solution.

3. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 2, characterized in that, When preparing the pre-emulsion, the mass ratio of butyl acrylate, methyl methacrylate, acrylic acid, the emulsifier and water is: (60-70):(30-40):(10-15):(3-5):(150-160); the mass concentration of the surfactant solution is 1.5-2%; the mass ratio of the water quality of the pre-emulsion to the mass of the bottom liquid is (150-160):(50-53).

4. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 3, characterized in that, The pre-emulsion and the initiator are added dropwise to the bottom liquid, and the dropping time is 3-3.5 h; the system temperature is maintained at 78-80 °C during the dropping process, and after the dropping is completed, it is kept warm at 78-80 °C for 1-1.5 h.

5. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 2 or 3 or 4, characterized in that, The mass ratio of the water quality of the pre-emulsion to the thickener is (150-160):(1-1.5).

6. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 1, wherein The density of the hollow glass microspheres is 0.1 to 0.28 g / cm 3 ; the mass ratio of the hollow glass microspheres is not less than 14% of the mass of the hollow glass microspheres / PMMA wind turbine blade core material.

7. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 1, wherein, The initiator is a high-temperature initiator or a normal-temperature initiator. The high-temperature initiator is benzoyl peroxide, azobisisobutyronitrile or azobisisoheptonitrile; the normal-temperature initiator is composed of benzoyl peroxide and a promoter, and the promoter is N,N-dimethylacetamide.

8. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 7, characterized in that, The mass of the high-temperature initiator is 1-3% of the total mass of polymethyl methacrylate and methyl methacrylate; the mass of benzoyl peroxide in the normal-temperature initiator is 1-2% of the total mass of polymethyl methacrylate and methyl methacrylate, and the mass of the promoter is 0.1-0.5% of the total mass of polymethyl methacrylate and methyl methacrylate.

9. The preparation method of the hollow glass microsphere / PMMA wind turbine blade core material according to claim 1, wherein, The curing and forming is vacuum hot pressing. When vacuum hot pressing, the pressure is 1-1.5 MPa, the temperature is from room temperature to 90 °C, and the time is 6-8 h.

10. A method for recycling hollow glass microsphere / PMMA wind turbine blade core material prepared by the preparation method of hollow glass microsphere / PMMA wind turbine blade core material according to any one of claims 1-9, characterized in that, It includes the following steps: The hollow glass microsphere / PMMA wind turbine blade core material is crushed and then dissolved in methyl methacrylate, and then solid-liquid separation is carried out. The solid obtained by solid-liquid separation is hollow glass microspheres, and the liquid obtained by solid-liquid separation is a mixture of polymethyl methacrylate and methyl methacrylate.