Composite protective layer, its preparation method, and protection device for wind turbine blade

Abstract

The present application discloses a composite protective layer, a preparation method thereof, and a protection device for a wind turbine blade. The composite protective layer includes a stacked first modified ultra-high molecular weight polyethylene layer and a modified polyethylene layer. By providing the stacked first modified ultra-high molecular weight polyethylene layer and the modified polyethylene layer, the first modified ultra-high molecular weight polyethylene layer is used to accelerate heat transfer, and its ultra-weather resistance and high impact resistance can resist natural damage for a long time. The modified polyethylene layer transfers heat to assist in removing ice and snow on the outer layer. The composite protective layer obtained by the cooperation of each protective layer is light in weight, soft and bendable, can be attached to the blade surface, will not bring excessive weight, does not affect the structural safety, and also has good de-icing efficiency and mechanical property retention rate.

Description

Technical Field

[0001] The present invention relates to the field of polymer materials, and particularly to a composite protective layer, a preparation method thereof, and a protection device for a wind turbine blade. Background Art

[0002] Wind energy is a clean, harmless, and renewable energy source. In addition, wind power generation has a short construction period and high efficiency, and is currently one of the main ways of clean energy power generation in China. Due to the environmental protection and high power generation characteristics of wind power generation, it has received more and more attention.

[0003] However, some wind turbines are in high-altitude and high-humidity environments, and it is easy to ice on the blade surface as the temperature drops. After the blade is covered with ice, its mass increases, and an uneven surface will be formed, which not only increases the load during blade operation, shortens the service life of the components connecting the blades, but also seriously affects the aerodynamic performance of the blade surface, resulting in a sharp reduction in the power generation of the wind turbine.

[0004] There are mainly two categories of traditional blade de-icing methods: one is active de-icing, that is, by inputting external energy to heat the blade surface, so that the ice melts and then is thrown out with the rotation of the blade. Commonly used methods include microwave de-icing, electrothermal de-icing, air flow de-icing, etc. However, active de-icing has the following disadvantages: loading an energy transmission device inside the blade increases the overall weight of the blade, affects structural safety, the built-in equipment is complex and not easy to maintain, and at the same time, the heating element is vulnerable to lightning strikes. The other is passive de-icing, which constructs a coating on the blade surface to change the surface contact angle or generate contact deformation, so that ice is difficult to adhere to the surface or forms broken ice and is easily thrown out with the rotation of the blade. Passive de-icing also has the following disadvantages: the preparation process of the coating is complex, the durability of the hydrophobic coating is poor, the de-icing effect is poor, and the attached ice cannot be completely removed. Summary of the Invention

[0005] Based on this, it is necessary to provide a composite protective layer with good weather resistance and good de-icing effect, a preparation method thereof, and a protection device for a wind turbine blade.

[0006] The present application provides a composite protective layer, including a stacked first modified ultra-high molecular weight polyethylene layer and a modified polyethylene layer;

[0007] Wherein, the first modified ultra-high molecular weight polyethylene layer comprises raw materials in the following weight parts:

[0008]

[0009] The modified polyethylene layer comprises raw materials in the following weight parts:

[0010] 70 parts to 100 parts of polyethylene, and 2 parts to 25 parts of a conductive material.

[0011] In one embodiment, it further includes a second modified ultra-high molecular weight polyethylene layer that contacts the side surface of the modified polyethylene layer away from the first modified ultra-high molecular weight polyethylene layer;

[0012] Wherein, the second modified ultra-high molecular weight polyethylene layer comprises raw materials in the following parts by weight:

[0013] 85 to 102 parts of second ultra-high molecular weight polyethylene, and

[0014] 0.5 to 12 parts of porous material.

[0015] In one embodiment, the molecular weights of the first ultra-high molecular weight polyethylene and the second ultra-high molecular weight polyethylene are each independently 1,000,000 to 2,000,000.

[0016] In one embodiment, one or more of the following conditions are satisfied:

[0017] (1) The modified polyethylene layer further comprises 0.01 to 5 parts of a first additive;

[0018] (2) The second modified ultra-high molecular weight polyethylene layer further comprises 0.01 to 5 parts of a second additive;

[0019] (3) The porous material comprises one or more of silicate, diatomite, silica gel, and activated carbon;

[0020] (4) The thickness of the second modified ultra-high molecular weight polyethylene layer is 0.1 mm to 3 mm.

[0021] In one embodiment, the first additive and the second additive each independently comprise 0.01 to 1 part of polyethylene wax, 0.01 to 3 parts of coupling agent, 0.01 to 1 part of stearic acid, 0.01 to 2 parts of antioxidant, and 0.01 to 1 part of polyvinylpyrrolidone.

[0022] In one embodiment, the ultraviolet absorber comprises one or more of 2,2'-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one), 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-n-octyloxybenzophenone, and zinc oxide.

[0023] In one embodiment, the radical scavenger includes one or more of bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-bis[(2,2,6,6-tetramethylpiperidyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidyl)imino]}, N,N'''-1,2-ethanediylbis[N-[3-[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-1,3,5-triazin-2-yl]amino]propyl]-N,N''-dibutyl-N,N''-bis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,3,5-triazine-2,4,6-triamine, and 2,2,6,6-tetramethylpiperidine 1-oxyl.

[0024] In one embodiment, the conductive material includes one or more of metal, carbon fiber, graphene, and carbon black.

[0025] In one embodiment, one or more of the following conditions are satisfied:

[0026] (1) The thickness of the first modified ultra-high molecular weight polyethylene layer is 0.5 mm to 4 mm;

[0027] (2) The thickness of the modified polyethylene layer is 0.1 mm to 3 mm;

[0028] (3) The resistance of the modified polyethylene layer is 1 Ω to 100 Ω.

[0029] The present application also provides a method for preparing the composite protective layer as described above, including the following steps:

[0030] Provide and mix the raw materials of each layer respectively to prepare the mixture of the first modified ultra-high molecular weight polyethylene layer and the mixture of the modified polyethylene layer;

[0031] Add the mixture of the first modified ultra-high molecular weight polyethylene layer and the mixture of the modified polyethylene layer into a co-extrusion device respectively, and perform extrusion to prepare the first modified ultra-high molecular weight polyethylene layer and the modified polyethylene layer.

[0032] In one embodiment, one or more of the following conditions are satisfied:

[0033] (1) The extrusion conditions of the first modified ultra-high molecular weight polyethylene layer include a screw temperature of 180 °C to 200 °C and a die head temperature of 220 °C to 225 °C;

[0034] (2) The extrusion conditions of the modified polyethylene layer include a screw temperature of 175 °C to 185 °C and a die head temperature of 220 °C to 225 °C.

[0035] Furthermore, the present application also provides a protection device for a wind turbine blade, including the composite protective layer as described above.

[0036] By arranging the laminated first modified ultra-high molecular weight polyethylene layer and modified polyethylene layer, the above-mentioned composite protective layer utilizes the first modified ultra-high molecular weight polyethylene layer to accelerate heat transfer. Its super weather resistance and high impact resistance can resist natural damage for a long time. The modified polyethylene layer transfers heat to assist in removing ice and snow on the outer layer. The composite protective layer obtained by the cooperation of each protective layer is light in weight, soft and bendable, can be attached to the blade surface, will not bring excessive weight, does not affect the structural safety, and also has good de-icing efficiency and mechanical property retention rate. Description of the Drawings

[0037] Figure 1 This is a composite protective layer provided by a specific example of the present application;

[0038] Figure 2 This is another composite protective layer provided by a specific example of the present application;

[0039] Description of the Reference Numerals: 10: Composite protective layer, 110: First modified ultra-high molecular weight polyethylene layer, 120: Modified polyethylene layer, 130: Second modified ultra-high molecular weight polyethylene layer. Detailed Embodiments

[0040] The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity and does not itself indicate the relationship between the various embodiments and / or arrangements discussed.

[0041] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the application, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically defined. In the description of the present application, "several" means at least one, such as one, two, etc., unless otherwise specifically defined.

[0042] Unless otherwise specified, all percentages, fractions, and ratios are calculated based on the total mass of the compositions of the present application. Unless otherwise specified, all masses of the listed ingredients are given for the content of the active substances, and thus they do not include solvents or by-products that may be contained in commercially available materials. The term "mass percentage content" herein can be represented by the symbol "%"

[0043] The terms "comprising", "including", "containing", "having", or other variants herein are intended to cover non-closed inclusion, and no distinction is made among these terms. The term "including" means that other steps and ingredients can be added without affecting the final result. The term "including" also includes the terms "consisting of" and "consisting essentially of". The compositions and methods / processes of the present application comprise, consist of, and consist essentially of the essential elements and limitations described herein, as well as any additional or optional ingredients, components, steps, or limitations described herein. No distinction is made among the terms "efficacy", "performance", "effect", and "efficiency" herein.

[0044] The words "preferably", "more preferably", etc. in the present application refer to the embodiments of the present application that can provide certain beneficial effects in certain cases. However, in the same or other cases, other embodiments may also be preferred. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not available, nor is it intended to exclude other embodiments from the scope of the present application.

[0045] When a numerical range is disclosed herein, the above range is considered continuous and includes the minimum and maximum values of the range, as well as each value between such minimum and maximum values. Further, when the range refers to integers, it includes each integer between the minimum and maximum values of the range. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all sub-ranges subsumed therein.

[0046] The present application, as Figure 1 shown, provides a composite protective layer 10, comprising a laminated first modified ultra-high molecular weight polyethylene layer 110 and a modified polyethylene layer 120;

[0047] Wherein, the first modified ultra-high molecular weight polyethylene layer 110 comprises the following raw materials in parts by weight:

[0048]

[0049] The modified polyethylene layer 120 comprises the following raw materials in parts by weight:

[0050] 70 to 100 parts of polyethylene, and

[0051] 2 to 25 parts of conductive material.

[0052] As Figure 2 shown, it further includes a second modified ultra-high molecular weight polyethylene layer 130 in contact with the surface of the modified polyethylene layer 120 away from the first modified ultra-high molecular weight polyethylene layer 110;

[0053] The second modified ultra-high molecular weight polyethylene layer 130 includes raw materials in the following weight parts:

[0054] 85 to 102 parts of second ultra-high molecular weight polyethylene, and

[0055] 0.5 to 12 parts of porous material.

[0056] This application provides a composite protective layer 10, which further includes a first modified ultra-high molecular weight polyethylene layer 110, a modified polyethylene layer 120, and a second modified ultra-high molecular weight polyethylene layer 130 that are stacked in sequence;

[0057] Among them, the first modified ultra-high molecular weight polyethylene layer 110 includes raw materials in the following weight parts:

[0058]

[0059] The modified polyethylene layer 120 includes raw materials in the following weight parts:

[0060] 75 to 90 parts of polyethylene, and,

[0061] 10 to 23 parts of conductive material;

[0062] The second modified ultra-high molecular weight polyethylene layer 130 includes raw materials in the following weight parts:

[0063] 87 to 99 parts of second ultra-high molecular weight polyethylene, and

[0064] 1 to 10 parts of porous material.

[0065] The first modified ultra-high molecular weight polyethylene layer 110 obtains super weather resistance by adding ultraviolet absorption aids and free radical scavengers, maintaining its high impact resistance characteristics, and can protect the blade from being invaded by external factors (such as rain erosion, insects, and sand and dust) for a long time. Adding graphene can accelerate the heat transfer in the first modified ultra-high molecular weight polyethylene layer 110, with better anti-icing and energy-saving effects, and combined with the self-lubricating performance of ultra-high molecular weight polyethylene itself, it reduces the adhesion of ice on its surface. In addition, ultra-high molecular weight polyethylene also has excellent insulation properties, which helps to develop a lightning protection system.

[0066] The modified polyethylene layer 120 is modified by a conductive material to play a role in transferring heat. It is connected to a power source through a wire, and the heat is directly transferred to the first modified ultra-high molecular weight polyethylene layer 110 to remove ice and snow on the blade.

[0067] The second modified ultra-high molecular weight polyethylene layer 130 is modified by using a porous material to obtain a composite material with a porous structure, which plays a good heat insulation role and can effectively reduce the transfer of heat generated by the heating unit to the inside of the wind turbine blade to be protected, achieving the purpose of energy conservation.

[0068] In a specific example, the molecular weights of the first ultra-high molecular weight polyethylene and the second ultra-high molecular weight polyethylene are each independently 1,000,000 to 2,000,000.

[0069] Furthermore, the molecular weights of the first ultra-high molecular weight polyethylene and the second ultra-high molecular weight polyethylene are each independently 1,200,000 to 1,800,000. Specifically, the molecular weights of the first ultra-high molecular weight polyethylene and the second ultra-high molecular weight polyethylene can each independently be, but are not limited to, 1,200,000, 1,300,000, 1,400,000, 1,500,000, 1,600,000, 1,700,000 or 1,800,000.

[0070] In a specific example, the porous material includes one or more of silicate, diatomaceous earth, silica gel, and activated carbon.

[0071] In a specific example, the modified polyethylene layer 120 further includes 0.01 part to 5 parts of a first additive.

[0072] Furthermore, the molecular weight of the polyethylene in the modified polyethylene layer 120 is 8,000 to 12,000. Specifically, the molecular weight of the polyethylene can be, but is not limited to, 8,000, 8,500, 9,000, 9,500, 10,000, 10,500, 11,000, 11,500 or 12,000.

[0073] In a specific example, the second modified ultra-high molecular weight polyethylene layer 130 further includes 0.01 part to 5 parts of a second additive.

[0074] In a specific example, the first additive and the second additive each independently include 0.01 part to 1 part of polyethylene wax, 0.01 part to 3 parts of a coupling agent, 0.01 part to 1 part of stearic acid, 0.01 part to 2 parts of an antioxidant, and 0.01 part to 1 part of polyvinylpyrrolidone.

[0075] Furthermore, the first additive includes 0.01 part to 2 parts of polyethylene wax, 0.01 part to 1 part of stearic acid, 0.01 part to 2 parts of antioxidant 1010, and 0.01 part to 1 part of polyvinylpyrrolidone PVP.

[0076] Further, the second auxiliary agent includes 0.01 part to 1 part of polyethylene wax, 0.01 part to 2 parts of titanate coupling agent, and 0.01 part to 1 part of silane coupling agent.

[0077] In a specific example, the ultraviolet absorber includes one or more of 2,2'-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one), 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-n-octyloxybenzophenone, and zinc oxide.

[0078] Further, the ultraviolet absorber includes one or more of TINUVIN B75, UV-326, UV-531, and zinc oxide.

[0079] In a specific example, the radical scavenger includes one or more of bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-bis[(2,2,6,6,-tetramethyl-piperidyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidyl)imino]}, N,N'''-1,2-ethanediylbis[N-[3-[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-1,3,5-triazin-2-yl]amino]propyl]-N,N''-dibutyl-N,N''-bis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,3,5-triazine-2,4,6-triamine, and 2,2,6,6-tetramethylpiperidine 1-oxyl.

[0080] Further, the radical scavenger includes one or more of RIASORB UV-770, UV-944, RIASORB UV-119, and TEMPO.

[0081] In a specific example, the conductive material includes one or more of metal, carbon fiber, graphene, and carbon black.

[0082] In a specific example, the thickness of the first modified ultra-high molecular weight polyethylene layer 110 is 0.5 mm to 4 mm. Further, the thickness of the first modified ultra-high molecular weight polyethylene layer 110 is 0.8 mm to 2 mm. Specifically, the thickness of the first modified ultra-high molecular weight polyethylene layer 110 can be, but is not limited to, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, or 2 mm.

[0083] In a specific example, the thickness of the modified polyethylene layer 120 is 0.1 mm to 3 mm. Further, the thickness of the modified polyethylene layer 120 is 0.2 mm to 1 mm. Specifically, the thickness of the modified polyethylene layer 120 can be, but is not limited to, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, or 1 mm.

[0084] In a specific example, the thickness of the second modified ultra-high molecular weight polyethylene layer 130 is 0.1 mm to 3 mm. Further, the thickness of the second modified ultra-high molecular weight polyethylene layer 130 is 0.2 mm to 1 mm. Specifically, the thickness of the second modified ultra-high molecular weight polyethylene layer 130 can be, but is not limited to, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, or 1 mm.

[0085] In a specific example, the resistance of the modified polyethylene layer 120 is 1 Ω to 100 Ω. Further, the resistance of the modified polyethylene layer 120 can be, but is not limited to, 1 Ω, 10 Ω, 20 Ω, 30 Ω, 40 Ω, 50 Ω, 60 Ω, 70 Ω, 80 Ω, 90 Ω, or 100 Ω.

[0086] The above composite protective layer 10 is formed by sequentially laminating a first modified ultra-high molecular weight polyethylene layer 110, a modified polyethylene layer 120, and a second modified ultra-high molecular weight polyethylene layer 130. The first modified ultra-high molecular weight polyethylene layer 110 is used to accelerate heat transfer, and its super weather resistance and high impact resistance can resist natural damage for a long time. The modified polyethylene layer 120 transfers heat to assist in removing ice and snow on the outer layer. The second modified ultra-high molecular weight polyethylene layer 130 has good heat insulation to prevent heat from being transferred to the protected blade. The composite protective layer 10 obtained by the cooperation of the three protective layers is light in weight, soft, and can be bent and deformed. It can be attached to the blade surface without adding too much weight and does not affect the structural safety. It also has good de-icing efficiency and mechanical property retention rate.

[0087] This application also provides a Figure 1 preparation method of the composite protective layer 10 as described above, including the following steps:

[0088] Provide and mix the raw materials for each layer respectively to prepare the mixture for the first modified ultra-high molecular weight polyethylene layer 110 and the mixture for the modified polyethylene layer 120;

[0089] Add the mixture for the first modified ultra-high molecular weight polyethylene layer 110 and the mixture for the modified polyethylene layer 120 into a co-extrusion device respectively and perform extrusion to prepare the first modified ultra-high molecular weight polyethylene layer 110 and the modified polyethylene layer 120.

[0090] The present application also provides a method for preparing the composite protective layer 10 as described above Figure 2 , comprising the following steps:

[0091] Provide and mix the raw materials for each layer respectively to prepare the mixture of the first modified ultra-high molecular weight polyethylene layer 110, the modified polyethylene layer 120, and the second modified ultra-high molecular weight polyethylene layer 130;

[0092] Respectively add the mixture of the first modified ultra-high molecular weight polyethylene layer 110, the modified polyethylene layer 120, and the second modified ultra-high molecular weight polyethylene layer 130 into a three-layer co-extrusion device for extrusion to prepare the first modified ultra-high molecular weight polyethylene layer 110, the modified polyethylene layer 120, and the second modified ultra-high molecular weight polyethylene layer 130.

[0093] It can be understood that before putting the above-mentioned mixture of the first modified ultra-high molecular weight polyethylene layer 110, the modified polyethylene layer 120, and the second modified ultra-high molecular weight polyethylene layer 130 into the co-extrusion device, it is placed at a temperature of 70°C to 90°C for 10 hours to 14 hours. Further, the above-mentioned placement temperature can be but is not limited to 70°C, 75°C, 80°C, 85°C, or 90°C, and the placement time can be but is not limited to 10 hours, 11 hours, 12 hours, 13 hours, or 14 hours.

[0094] In a specific example, the extrusion conditions of the first modified ultra-high molecular weight polyethylene layer 110 include a screw temperature of 180°C to 200°C and a die head temperature of 220°C to 225°C.

[0095] Further, in the extrusion conditions of the first modified ultra-high molecular weight polyethylene layer 110, the screw temperature can be but is not limited to 180°C, 185°C, 190°C, 195°C, or 200°C, and the die head temperature can be but is not limited to 220°C, 221°C, 222°C, 223°C, 224°C, or 225°C.

[0096] In a specific example, the extrusion conditions of the modified polyethylene layer 120 include a screw temperature of 175°C to 185°C and a die head temperature of 220°C to 225°C.

[0097] Further, in the extrusion conditions of the modified polyethylene layer 120, the screw temperature can be but is not limited to 175°C, 177°C, 179°C, 181°C, 183°C, or 185°C, and the die head temperature can be but is not limited to 220°C, 221°C, 222°C, 223°C, 224°C, or 225°C.

[0098] In a specific example, the extrusion conditions of the second modified ultra-high molecular weight polyethylene layer 130 include a screw temperature of 185°C to 210°C and a die head temperature of 220°C to 225°C.

[0099] Further, in the extrusion conditions of the second modified ultra-high molecular weight polyethylene layer 130, the screw temperature can be, but is not limited to, 185°C, 190°C, 195°C, 200°C, 205°C or 210°C, and the die head temperature can be, but is not limited to, 220°C, 221°C, 222°C, 223°C, 224°C or 225°C.

[0100] Further, the present application also provides a protection device for a wind turbine blade, including the composite protective layer 10 as described above.

[0101] It can be understood that the surface of the second modified ultra-high molecular weight polyethylene layer 130 away from the modified polyethylene layer 120 is surface-treated so that it can achieve good adhesion with the wind turbine blade substrate through a structural adhesive. Further, the above surface treatment can be, but is not limited to, vacuum plasma treatment.

[0102] The following further elaborates on the composite protective layer and its preparation method of the present application in conjunction with specific embodiments. The raw materials used in the following embodiments are all commercially available products unless otherwise specified.

[0103] Example 1

[0104] This example provides a composite protective layer, including a first modified ultra-high molecular weight polyethylene layer with a thickness of 1 mm, a modified polyethylene layer with a thickness of 0.5 mm, and a second modified ultra-high molecular weight polyethylene layer with a thickness of 0.5 mm, which are laminated in sequence;

[0105] Among them, the raw materials of the first modified ultra-high molecular weight polyethylene layer include 90 parts of ultra-high molecular weight polyethylene with a molecular weight of 1.5 million, 4 parts of ultraviolet absorber, 1 part of radical scavenger, and 5 parts of graphene. The ultraviolet absorber includes UV-326 and zinc oxide with a mass ratio of 1:3, and the radical scavenger includes RIASORB UV-119 and TEMPO with a mass ratio of 1:1;

[0106] The raw materials of the modified polyethylene layer include 77.7 parts of polyethylene with a molecular weight of 10,000, 20 parts of conductive material carbon black, 0.5 parts of polyethylene wax, 0.3 parts of stearic acid, 0.5 parts of antioxidant 1010, and 1 part of polyvinylpyrrolidone PVP;

[0107] The raw materials of the second modified ultra-high molecular weight polyethylene layer include 89.5 parts of ultra-high molecular weight polyethylene with a molecular weight of 1.5 million, 8 parts of porous material diatomite, 0.5 parts of polyethylene wax, 1 part of titanate coupling agent, and 1 part of silane coupling agent.

[0108] Example 2

[0109] The difference between this embodiment and Embodiment 1 lies in that there are only the first modified ultra-high molecular weight polyethylene layer and the modified polyethylene layer.

[0110] The preparation method of the composite protective layer in this embodiment includes the following steps:

[0111] Prepare materials according to the raw materials of each layer above, mix them separately, prepare the mixture for the first modified ultra-high molecular weight polyethylene layer, the mixture for the modified polyethylene layer, and the mixture for the second modified ultra-high molecular weight polyethylene layer, and place them at 80 °C for 12 hours to remove moisture;

[0112] Add the above-mentioned mixture for the first modified ultra-high molecular weight polyethylene layer, the mixture for the modified polyethylene layer, and the mixture for the second modified ultra-high molecular weight polyethylene layer into a three-layer co-extrusion casting device respectively, obtain a three-layer composite sheet through co-extrusion, then emboss and cut to obtain a suitable product.

[0113] The temperatures of the three screws of the three-layer co-extrusion device are respectively:

[0114]

[0115] The die head temperature of the three-layer co-extrusion device:

[0116] Die Zone 1 Temperature (°C) Die Zone 2 Temperature (°C) Die Zone 3 Temperature (°C) Die Zone 4 Temperature (°C) Die Zone 5 Temperature (°C) 223 223 220 220 220

[0117] Comparative Example 1

[0118] The difference between this comparative example and Embodiment 1 lies in that there is only the first modified ultra-high molecular weight polyethylene layer.

[0119] Comparative Example 2

[0120] The difference between this comparative example and Embodiment 1 lies in that there are only the first modified ultra-high molecular weight polyethylene layer and the second modified ultra-high molecular weight polyethylene layer.

[0121] Comparative Example 3

[0122] The difference between this comparative example and Embodiment 1 lies in that there are only the modified polyethylene layer and the second modified ultra-high molecular weight polyethylene layer.

[0123] Comparative Example 4

[0124] The difference between this comparative example and Embodiment 1 is the raw materials and proportions of the ultraviolet absorber in the first modified ultra-high molecular weight polyethylene layer in Comparative Examples 4-1 to 4-4. The specific differences are summarized in the following table.

[0125]

[0126] Test method and test results

[0127] Weather resistance test: Place the composite material in an ultraviolet aging chamber for 1000 h according to the ISO 16474-3-2013 standard, and test its mechanical properties before and after 1000 hours of placement. The calculation method of the mechanical property retention rate is as follows:

[0128] Anti-icing test: Spray water droplets on the surface of the composite material, then place it in an environment of -18°C for 48 hours, and then connect the conductive layer to transfer heat. Compare the remaining area of the ice layer before and after power-on. The results of the above examples and comparative examples are summarized in the following table.

[0129]

[0130]

[0131] It can be seen from the above data that the composite material provided by the present application realizes the effects of both good mechanical properties and de-icing efficiency for the raw material ratio in the composite material and through interlayer compounding. The first modified ultra-high molecular weight polyethylene layer is used to accelerate heat transfer, and the ultra-high weather resistance and high impact resistance can resist natural damage for a long time. The modified polyethylene layer transfers heat to assist in removing the outer layer of ice and snow. The composite protective layer obtained by the cooperation of the protective layer is light in weight, soft and bendable, can be attached to the surface of the blade, will not bring extra weight, does not affect the structural safety, and also has good de-icing efficiency and mechanical property retention rate.

[0132] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0133] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0134] The above-described embodiments merely represent several implementation manners of the present application, facilitating a specific and detailed understanding of the technical solution of the present application. However, it should not be construed as a limitation on the scope of patent protection of the application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can be made, and these all fall within the protection scope of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning, or limited experiments based on the technical solution provided by the present application are all within the protection scope of the appended claims of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the content of the appended claims, and the specification can be used to explain the content of the claims.

Claims

1. A composite protective layer, characterized in that, It includes a stacked first modified ultra-high molecular weight polyethylene layer and a modified polyethylene layer; Among them, the first modified ultra-high molecular weight polyethylene layer includes raw materials in the following parts by weight: The modified polyethylene layer includes raw materials in the following parts by weight: 70 to 100 parts of polyethylene, and 2 to 25 parts of a conductive material.

2. The composite protective layer according to claim 1, wherein It further includes a second modified ultra-high molecular weight polyethylene layer in contact with the surface of the modified polyethylene layer away from the first modified ultra-high molecular weight polyethylene layer; Among them, the second modified ultra-high molecular weight polyethylene layer includes raw materials in the following parts by weight: 85 to 102 parts of second ultra-high molecular weight polyethylene, and 0.5 to 12 parts of a porous material.

3. The composite protective layer according to claim 2, wherein, The molecular weights of the first ultra-high molecular weight polyethylene and the second ultra-high molecular weight polyethylene are independently 1,000,000 to 2,000,000.

4. The composite protective layer according to claim 2, characterized in that, Meet one or more of the following conditions: (1) The modified polyethylene layer further includes 0.01 to 5 parts of a first auxiliary agent; (2) The second modified ultra-high molecular weight polyethylene layer further includes 0.01 to 5 parts of a second auxiliary agent; (3) The porous material includes one or more of silicate, diatomite, silica gel, and activated carbon; (4) The thickness of the second modified ultra-high molecular weight polyethylene layer is 0.1 mm to 3 mm.

5. The composite protective layer according to claim 4, characterized in that, The first auxiliary agent and the second auxiliary agent each independently include 0.01 to 1 part of polyethylene wax, 0.01 to 3 parts of a coupling agent, 0.01 to 1 part of stearic acid, 0.01 to 2 parts of an antioxidant, and 0.01 to 1 part of polyvinylpyrrolidone.

6. The composite protective layer according to claim 1, characterized in that, The ultraviolet absorber includes one or more of 2,2'-(1,4-phenylene) bis(4H-3,1-benzoxazin-4-one), 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-n-octyloxybenzophenone, and zinc oxide.

7. The composite protective layer according to claim 1, characterized in that, The radical scavenger includes one or more of bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-bis[(2,2,6,6-tetramethyl-piperidyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidyl)imino]}, N,N”'-1,2-ethanediylbis[N-[3-[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-1,3,5-triazin-2-yl]amino]propyl]-N,N”-dibutyl-N,N”-bis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,3,5-triazine-2,4,6-triamine, and 2,2,6,6-tetramethylpiperidine oxide.

8. The composite protective layer according to claim 1, wherein The conductive material includes one or more of metal, carbon fiber, graphene, and carbon black.

9. The composite protective layer according to any one of claims 1 to 8, characterized in that, Meet one or more of the following conditions: (1) The thickness of the first modified ultra-high molecular weight polyethylene layer is 0.5 mm to 4 mm; (2) The thickness of the modified polyethylene layer is 0.1 mm to 3 mm; (3) The resistance of the modified polyethylene layer is 1 Ω to 100 Ω.

10. A method for preparing a composite protective layer according to any one of claims 1 to 9, characterized in that, It includes the following steps: Provide and mix the raw materials of each layer respectively to prepare the mixture of the first modified ultra-high molecular weight polyethylene layer and the mixture of the modified polyethylene layer; Add the mixture of the first modified ultra-high molecular weight polyethylene layer and the mixture of the modified polyethylene layer into the co-extrusion equipment respectively and conduct extrusion to prepare the first modified ultra-high molecular weight polyethylene layer and the modified polyethylene layer.

11. The preparation method according to claim 10, characterized in that, Meet one or more of the following conditions: (1) The extrusion conditions of the first modified ultra-high molecular weight polyethylene layer include that the screw temperature is 180 °C to 200 °C and the die head temperature is 220 °C to 225 °C; (2) The extrusion conditions of the modified polyethylene layer include that the screw temperature is 175 °C to 185 °C and the die head temperature is 220 °C to 225 °C.

12. A protection device for a wind power blade, characterized in that, It includes the composite protective layer as described in any one of claims 1 to 9.

Images