Epoxy resin matrix material for carbon fiber pultrusion plate, carbon fiber reinforced pultrusion plate and preparation method and application of carbon fiber reinforced pultrusion plate

Abstract

The invention relates to an epoxy resin matrix material for a carbon fiber pultrusion plate, a carbon fiber reinforced pultrusion plate and a preparation method and application of the carbon fiber reinforced pultrusion plate. The adhesive comprises the following components in parts by weight: 100 parts of bisphenol A epoxy resin, 105 parts of methyl tetrahydrophthalic anhydride, 1-2 parts of phenol, 1-2 parts of a release agent, 2-5 parts of maleic anhydride, 1-5 parts of aluminum hydroxide and 1-5 parts of polypropylene glycol. The epoxy resin matrix material for the carbon fiber pultrusion plate, the carbon fiber reinforced pultrusion plate and the preparation method and application of the epoxy resin matrix material and the carbon fiber reinforced pultrusion plate are provided to solve the problems that existing fibers are directly soaked in epoxy resin, the wettability of an epoxy resin matrix is poor, tight interaction is difficult to form, and the service life is long. The difference between the mechanical property, the fatigue property and the like of the composite material and theoretical values is large, and the adhesive film is extremely easy to generate in the production process; and the yield is reduced. And the combination of fibers and perfusion resin is poor, so that the blade manufacturing difficulty is increased, and the blade use safety and reliability are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of pultruded plate preparation, and in particular to an epoxy resin matrix material for a carbon fiber pultruded plate, a carbon fiber reinforced pultruded plate, and a preparation method and application thereof. Background Art

[0002] To improve the utilization efficiency of wind turbine blades, reduce the cost of electricity, and develop offshore and low-wind resources, wind turbines are gradually developing towards larger, lighter units. Wind turbine blades are a critical component of the entire wind turbine system. Increasing blade length exponentially increases blade weight, placing high strength modulus and low weight requirements on the blade's main beam. Currently, the industry primarily uses high-strength, high-modulus, and highly corrosion-resistant carbon fiber pultruded sheet for blades over 100 meters in length. Large-tow carbon fiber with a density of 48K or higher is widely used in this beam due to its low production cost and high single-strength performance.

[0003] The performance of carbon fiber pultruded sheet materials is determined by the properties of the carbon fiber and epoxy resin themselves, as well as the interfacial properties between the two. Excellent interfacial bonding is a necessary prerequisite for fully realizing its performance. However, due to the inherent surface chemical inertness of carbon fiber, it has poor wettability with the epoxy resin matrix, making it difficult to form a close interaction. This, on the one hand, leads to a large gap between the mechanical and fatigue properties of the composite material and the theoretical values. On the other hand, it increases the difficulty of the production process, easily causing pultrusion process problems such as sticking, and increasing production costs. The poor bonding performance of the epoxy resin used for infusion in the later production of blades increases the risk of blade use and greatly restricts the development and application of carbon fiber pultruded sheet materials in the wind power industry.

[0004] Therefore, in order to solve the above problems, the present invention urgently needs to provide an epoxy resin matrix material for carbon fiber pultruded plate, carbon fiber reinforced pultruded plate, and a preparation method and application thereof. Summary of the Invention

[0005] The purpose of the present invention is to provide an epoxy resin matrix material for carbon fiber pultruded sheet, carbon fiber reinforced pultruded sheet, and a preparation method and application thereof. The proposal of the epoxy resin matrix material for carbon fiber pultruded sheet solves the problem in the prior art that the fiber is directly impregnated in epoxy resin, the epoxy resin matrix has poor wettability, and it is difficult to form a close interaction, which easily leads to a large gap between the mechanical, fatigue and other properties of the composite material and the theoretical value, and it is very easy to produce process problems such as mucous membrane during the production process, thereby reducing the yield rate; in addition, the fiber has poor bonding with the infusion resin, which increases the difficulty of blade production and reduces the safety and reliability of blade use.

[0006] The present invention provides an epoxy resin matrix material for carbon fiber pultruded plates, which comprises, by weight, 100 parts of bisphenol A epoxy resin, 105 parts of methyltetrahydrophthalic anhydride, 1-2 parts of phenol, 1-2 parts of a release agent, 2-5 parts of maleic anhydride, 1-5 parts of aluminum hydroxide and 1-5 parts of polypropylene glycol.

[0007] Preferably, the particle size of aluminum hydroxide is ≤4 μm.

[0008] Preferably, the molecular weight of the polypropylene glycol is 1000.

[0009] Preferably, the phenol is 2,4,6-tris(dimethylaminomethyl)phenol;

[0010] The release agent is release agent INT-1890M or release agent g-172;

[0011] The viscosity of bisphenol A epoxy resin is 5000-14000 mPa·s.

[0012] Preferably, the acid value of methyltetrahydrophthalic anhydride is 350-700 mg KOH / g.

[0013] The present invention also provides a method for preparing carbon fiber reinforced pultruded sheet materials, comprising the following steps: impregnating carbon fiber into an epoxy resin matrix material for carbon fiber pultruded sheet materials as described in any one of the above-mentioned methods; after impregnation, pulling the impregnated carbon fiber into a heating and curing mold, heating and curing the mold, cutting, and winding to obtain a pultruded sheet material for a pultruded main beam of a wind turbine blade.

[0014] Preferably, in the pultruded plate, the weight fraction of the carbon fiber is 64-70 parts, and the weight fraction of the modified resin matrix is 30-35 parts.

[0015] Preferably, the heating and curing mold includes a front heating and curing zone and a post heating and curing zone, the front heating and curing zone is divided into three temperature zones in sequence, and the temperatures are set to 140-150°C, 165-175°C and 185-195°C in sequence; the post heating and curing zone is divided into four temperature zones, and the temperatures are set to 60-190°C, 140-180°C, 120-160°C and 100-140°C in sequence.

[0016] The present invention also provides a carbon fiber reinforced pultruded plate obtained based on the preparation method of the carbon fiber reinforced pultruded plate as described in any one of the above.

[0017] The present invention also provides a use of the carbon fiber reinforced pultruded plate material as described above in a pultruded main beam of a wind turbine blade.

[0018] The epoxy resin matrix material for carbon fiber pultruded sheet, carbon fiber reinforced pultruded sheet, preparation method and application thereof provided by the present invention have the following improvements compared with the prior art:

[0019] 1. The epoxy resin matrix material for carbon fiber pultruded sheet provided by the present invention is prepared by adding aluminum hydroxide, maleic anhydride and polypropylene glycol to bisphenol A epoxy resin at the same time, which can improve the fluidity of bisphenol A epoxy resin and ensure the mechanical properties of the prepared carbon fiber pultruded sheet.

[0020] 2. The epoxy resin matrix material for the carbon fiber pultruded sheet provided by the present invention is prepared by introducing aluminum hydroxide into the bisphenol A epoxy resin. The aluminum hydroxide is dispersed in the bisphenol A epoxy resin to prepare the carbon fiber pultruded sheet. When the carbon fiber pultruded sheet is subjected to external force and cracks propagate, the elastic modulus of the added aluminum hydroxide is different from that of the bisphenol A epoxy resin. When the cracks encounter the aluminum hydroxide, they will be deflected and continue to propagate around the particles, thereby increasing the path length of the crack propagation and consuming more energy.

[0021] 3. The epoxy resin matrix material for carbon fiber pultruded sheet provided by the present invention limits the particle size of the added aluminum hydroxide to below 4 μm, which has better dispersibility and avoids agglomeration. It can span between the two surfaces of the crack and play a bridging role. This bridging effect can resist the opening of the crack through the interfacial force between the particles and the matrix, thereby inhibiting the further expansion of the crack and playing a toughening role.

[0022] 4. The epoxy resin matrix material for carbon fiber pultruded sheet provided by the present invention, the epoxy resin matrix material for carbon fiber pultruded sheet provided, introduces polypropylene glycol into the bisphenol A epoxy resin matrix material, firstly, polypropylene glycol can make aluminum hydroxide better dispersed in the matrix, avoid filler agglomeration, and aluminum hydroxide can be more evenly distributed inside the material, give full play to its reinforcing effect, and improve the mechanical properties such as modulus and hardness of the material; secondly, polypropylene glycol has a long flexible carbon chain structure. When polypropylene glycol is mixed with epoxy resin, the molecular chain will participate in the curing network of bisphenol A epoxy resin and be embedded in the originally rigid epoxy resin cross-linked network as a flexible chain segment. These flexible chain segments can increase the activity of the molecular chain, so that the cured epoxy resin can be more flexible when subjected to external forces. When the carbon fiber pultruded sheet is subjected to external impact, these dispersed phase regions can act as stress concentration points, triggering the formation of silver crazing and shear bands. The formation and development of silver crazing and shear bands can absorb a large amount of impact energy, preventing the rapid expansion of cracks, thereby improving the toughness of the bisphenol A epoxy resin. Polypropylene glycol has active end groups, such as carboxyl, amino, and epoxy groups, which can chemically react with the epoxy resin, connecting the polypropylene glycol and epoxy resin through covalent bonds, resulting in a good interfacial bonding between the polypropylene glycol and epoxy resin. This strong interfacial interaction facilitates the effective transfer of stress to the polypropylene glycol phase region when subjected to stress, giving full play to the toughening effect of polypropylene glycol, allowing the dispersed phase to better absorb and dissipate energy, and improving the impact resistance of the epoxy resin.

[0023] 5. The epoxy resin matrix material for the carbon fiber pultruded sheet provided by the present invention uses polypropylene glycol with a molecular weight of 1000. Because of its moderate viscosity, it is easy to disperse evenly in the epoxy resin; at the same time, it avoids the excessively long chain segments caused by the high molecular weight, resulting in incomplete cross-linking reaction and reduced performance of the carbon fiber pultruded sheet.

[0024] 6. The epoxy resin matrix material for carbon fiber pultruded plates provided by the present invention, the epoxy resin matrix material for carbon fiber pultruded plates, introduces maleic anhydride into the epoxy resin matrix material, participates in the curing reaction of the epoxy resin, and can chemically react with active groups such as hydroxyl groups in polypropylene glycol. During the reaction, it can act as a bridge to connect the polypropylene glycol molecules, promote the reaction, and improve the crosslinking degree and reaction conversion rate of the system. DETAILED DESCRIPTION

[0025] The technical solution of the present invention will be described clearly and completely below. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] The invention provides an epoxy resin matrix material for carbon fiber pultruded plates. The epoxy resin matrix material comprises, by weight, 100 parts of bisphenol A epoxy resin, 105 parts of methyltetrahydrophthalic anhydride, 1-2 parts of phenol, 1-2 parts of a release agent, 2-5 parts of maleic anhydride, 1-5 parts of aluminum hydroxide and 1-5 parts of polypropylene glycol.

[0027] Specifically, the particle size of aluminum hydroxide is ≤4 μm.

[0028] Specifically, the molecular weight of the polypropylene glycol is 1,000.

[0029] Specifically, the phenol is 2,4,6-tris(dimethylaminomethyl)phenol;

[0030] The release agent is release agent INT-1890M or release agent g-172;

[0031] The viscosity of bisphenol A epoxy resin is 5000-14000 mPa·s.

[0032] Specifically, the acid value of methyltetrahydrophthalic anhydride is 350-700 mg KOH / g.

[0033] The present invention also provides a method for preparing carbon fiber reinforced pultruded sheet materials, comprising the following steps: impregnating carbon fiber into an epoxy resin matrix material for carbon fiber pultruded sheet materials as described in any one of the above-mentioned methods; after impregnation, pulling the impregnated carbon fiber into a heating and curing mold, heating and curing the mold, cutting, and winding to obtain a pultruded sheet material for a pultruded main beam of a wind turbine blade.

[0034] Specifically, in the pultruded plate, the weight fraction of the carbon fiber is 64-70 parts, and the weight fraction of the modified resin matrix is 30-35 parts.

[0035] Specifically, the heating and curing mold includes a front heating and curing zone and a post heating and curing zone. The front heating and curing zone is divided into three temperature zones in sequence, and the temperatures are set to 140-150°C, 165-175°C and 185-195°C in sequence; the post heating and curing zone is divided into four temperature zones, and the temperatures are set to 60-190°C, 140-180°C, 120-160°C and 100-140°C in sequence.

[0036] The present invention also provides a carbon fiber reinforced pultruded plate obtained based on the preparation method of the carbon fiber reinforced pultruded plate as described in any one of the above.

[0037] The present invention also provides a use of the carbon fiber reinforced pultruded plate material as described above in a pultruded main beam of a wind turbine blade.

[0038] The epoxy resin matrix material for carbon fiber pultruded plates provided by the present invention is characterized in that aluminum hydroxide, maleic anhydride and polypropylene glycol are simultaneously added to bisphenol A epoxy resin, thereby improving the fluidity of the bisphenol A epoxy resin and ensuring the mechanical properties of the prepared carbon fiber pultruded plates. The addition of polypropylene glycol can solve the problem that the existing fibers are directly impregnated in epoxy resin, the epoxy resin matrix has poor wettability, and it is difficult to form a close interaction, which easily leads to a large difference between the mechanical and fatigue properties of the composite material and the theoretical values, and process problems such as mucous membrane are easily generated during the production process, which reduces the yield rate. In addition, the fibers have poor bonding with the infusion resin, which increases the difficulty of blade production and reduces the safety and reliability of the blades.

[0039] The present invention introduces aluminum hydroxide into bisphenol A epoxy resin, and the aluminum hydroxide is dispersed in the bisphenol A epoxy resin to prepare a carbon fiber pultruded plate. When the carbon fiber pultruded plate is subjected to an external force and cracks propagate, the elastic modulus of the added aluminum hydroxide is different from that of the bisphenol A epoxy resin. When the cracks encounter the aluminum hydroxide, they deflect and continue to propagate around the particles, thereby increasing the path length of the crack propagation and consuming more energy.

[0040] The present invention limits the particle size of the added aluminum hydroxide to below 4 μm, which has better dispersibility and avoids agglomeration. The aluminum hydroxide can span between the two surfaces of the crack and play a bridging role. This bridging effect can resist the opening of the crack through the interfacial force between the particles and the matrix, thereby inhibiting further expansion of the crack and playing a toughening role.

[0041] The epoxy resin matrix material for carbon fiber pultruded plates provided by the present invention introduces polypropylene glycol into the bisphenol A epoxy resin matrix material. First, polypropylene glycol can make aluminum hydroxide better dispersed in the matrix, avoid filler agglomeration, and aluminum hydroxide can be more evenly distributed inside the material, giving full play to its reinforcing effect, and improving the mechanical properties of the material such as modulus and hardness; secondly, polypropylene glycol has a long flexible carbon chain structure. When polypropylene glycol is mixed with epoxy resin, the molecular chain will participate in the curing network of bisphenol A epoxy resin and be embedded in the originally rigid epoxy resin cross-linked network as a flexible chain segment. These flexible chain segments can increase the activity of the molecular chain, so that the molecular chains of the cured epoxy resin can be mutually connected when subjected to external force. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture. The bisphenol A epoxy resin is a material that is difficult to manufacture and difficult to manufacture.

[0042] The present invention selects polypropylene glycol with a molecular weight of 1000 because of its moderate viscosity and easy to disperse evenly in the epoxy resin; at the same time, it avoids the excessively long chain segments caused by the high molecular weight, resulting in incomplete cross-linking reaction and reduced performance of the carbon fiber pultruded plate.

[0043] The epoxy resin matrix material for carbon fiber pultruded plates provided by the present invention introduces maleic anhydride into the epoxy resin matrix material to participate in the curing reaction of the epoxy resin and can chemically react with active groups such as hydroxyl groups in polypropylene glycol. During the reaction, it can serve as a bridge to connect polypropylene glycol molecules, promote the reaction, and improve the crosslinking degree and reaction conversion rate of the system.

[0044] Example 1

[0045] The present invention also provides a method for preparing a carbon fiber reinforced pultruded plate, comprising the following steps:

[0046] 101) mixing, by weight, 100 parts of bisphenol A epoxy resin, 105 parts of methyltetrahydrophthalic anhydride, 1 part of phenol, 1 part of a release agent, 2 parts of maleic anhydride, 1 part of aluminum hydroxide, and 1 part of polypropylene glycol to obtain a modified epoxy resin matrix material;

[0047] 102) The carbon fibers are impregnated in an epoxy resin matrix material. After impregnation, the carbon fibers are pulled into a heating and curing mold, heated and cured to form, cut, and rolled to obtain a pultruded sheet for a pultruded main beam of a wind turbine blade.

[0048] In the pultruded plate of this embodiment, the weight fraction of carbon fiber is 64 parts, and the weight fraction of modified resin matrix is 30 parts.

[0049] The particle size of the aluminum hydroxide in this embodiment is ≤4 μm.

[0050] The molecular weight of the polypropylene glycol in this embodiment is 1000.

[0051] The phenol in the present embodiment is 2,4,6-tris(dimethylaminomethyl)phenol.

[0052] The release agent in this embodiment is release agent INT-1890M.

[0053] The viscosity of the bisphenol A epoxy resin in this embodiment is 9000-14000 mPa·s.

[0054] The acid value of the methyltetrahydrophthalic anhydride in this embodiment is 400-600 mg KOH / g.

[0055] The heating and curing mold of this embodiment includes a front heating and curing zone and a rear heating and curing zone. The front heating and curing zone is divided into three temperature zones in sequence, and the temperatures are set to 140°C, 165°C and 185°C in sequence; the rear heating and curing zone is divided into four temperature zones, and the temperatures are set to 160°C, 140°C, 120°C and 100°C in sequence.

[0056] The carbon fiber reinforced pultruded sheet obtained in this example is used to prepare the pultruded main beam of a wind turbine blade. The mechanical properties of the obtained carbon fiber reinforced pultruded sheet are shown in Table 1.

[0057] Example 2

[0058] The present invention also provides a method for preparing a carbon fiber reinforced pultruded plate, comprising the following steps: 101) mixing, by weight, 100 parts of bisphenol A epoxy resin, 105 parts of methyltetrahydrophthalic anhydride, 2 parts of phenol, 2 parts of a release agent, 5 parts of maleic anhydride, 5 parts of aluminum hydroxide, and 5 parts of polypropylene glycol to obtain a modified epoxy resin matrix material;

[0059] The carbon fibers are impregnated with an epoxy resin matrix material. After impregnation, the carbon fibers are drawn into a heat-curing mold, heat-cured and formed, cut, and rolled to obtain a pultruded sheet material for use in pultruded main beams of wind turbine blades. In this embodiment, the pultruded sheet material comprises 70 parts by weight of the carbon fibers and 35 parts by weight of the modified resin matrix.

[0060] The aluminum hydroxide in this embodiment is micron-sized aluminum hydroxide, and the particle size of the aluminum hydroxide is ≤4 μm.

[0061] The molecular weight of the polypropylene glycol in this embodiment is 1000.

[0062] The phenol in the present embodiment is 2,4,6-tris(dimethylaminomethyl)phenol.

[0063] The release agent in this embodiment is release agent g-172.

[0064] The viscosity of the bisphenol A epoxy resin in this embodiment is 8000-10000 mPa·s.

[0065] The acid value of the methyltetrahydrophthalic anhydride in this embodiment is 500-700 mg KOH / g.

[0066] The heating and curing mold of this embodiment includes a front heating and curing zone and a rear heating and curing zone. The front heating and curing zone is divided into three temperature zones in sequence, and the temperatures are set to 150°C, 175°C and 195°C in sequence; the rear heating and curing zone is divided into four temperature zones, and the temperatures are set to 190°C, 180°C, 160°C and 140°C in sequence.

[0067] The carbon fiber reinforced pultruded sheet obtained in this example is used to prepare the pultruded main beam of a wind turbine blade. The mechanical properties of the obtained carbon fiber reinforced pultruded sheet are shown in Table 1.

[0068] Example 3

[0069] The present invention also provides a method for preparing a carbon fiber reinforced pultruded plate, comprising the following steps: 101) mixing, by weight, 100 parts of bisphenol A epoxy resin, 105 parts of methyltetrahydrophthalic anhydride, 1.5 parts of phenol, 1.5 parts of a release agent, 4 parts of maleic anhydride, 3 parts of aluminum hydroxide, and 3 parts of polypropylene glycol to obtain a modified epoxy resin matrix material;

[0070] The carbon fiber is impregnated in an epoxy resin matrix material. After impregnation, the carbon fiber is pulled into a heating and curing mold, heated and cured to form, cut, and rolled to obtain a pultruded sheet for the pultruded main beam of a wind turbine blade.

[0071] In the pultruded plate of this embodiment, the weight fraction of carbon fiber is 65 parts, and the weight fraction of modified resin matrix is 32 parts.

[0072] The aluminum hydroxide in this embodiment is micron-sized aluminum hydroxide, and the particle size of the aluminum hydroxide is ≤4 μm.

[0073] The molecular weight of the polypropylene glycol in this embodiment is 1000.

[0074] The phenol in the present embodiment is 2,4,6-tris(dimethylaminomethyl)phenol.

[0075] The release agent in this embodiment is release agent g-172.

[0076] The viscosity of the bisphenol A epoxy resin in this embodiment is 5000-8000 mPa·s.

[0077] The acid value of the methyltetrahydrophthalic anhydride in this embodiment is 350-620 mg KOH / g.

[0078] The heating and curing mold of this embodiment includes a front heating and curing zone and a rear heating and curing zone. The front heating and curing zone is divided into three temperature zones in sequence, and the temperatures are set to 145°C, 170°C and 190°C in sequence; the rear heating and curing zone is divided into four temperature zones, and the temperatures are set to 150°C, 160°C, 150°C and 120°C in sequence.

[0079] The carbon fiber reinforced pultruded sheet obtained in this example is used to prepare the pultruded main beam of a wind turbine blade. The mechanical properties of the obtained carbon fiber reinforced pultruded sheet are shown in Table 1.

[0080] Comparative Example 1

[0081] The difference between this comparative example and Example 1 is that the modified epoxy resin matrix material does not contain aluminum hydroxide and polypropylene glycol. The other ingredients and the preparation steps of the carbon fiber reinforced pultruded plate are the same as those in Example 1. The mechanical properties of the obtained carbon fiber reinforced pultruded plate are shown in Table 1.

[0082] Comparative Example 2

[0083] The difference between this comparative example and Example 1 is that the modified epoxy resin matrix material does not contain polypropylene glycol. The other ingredients and the preparation steps of the carbon fiber reinforced pultruded plate are the same as those in Example 1. The mechanical properties of the obtained carbon fiber reinforced pultruded plate are shown in Table 1.

[0084] Comparative Example 3

[0085] The difference between this comparative example and Example 1 is that maleic anhydride is not contained in the modified epoxy resin matrix material. The other ingredients and the preparation steps of the carbon fiber reinforced pultruded plate are the same as those in Example 1. The mechanical properties of the obtained carbon fiber reinforced pultruded plate are shown in Table 1.

[0086] Comparative Example 4

[0087] The difference between this comparative example and Example 1 is that the particle size of the aluminum hydroxide is 5-10 μm. The mechanical properties of the obtained carbon fiber reinforced pultruded plate are shown in Table 1.

[0088] Comparative Example 5

[0089] The only difference between this comparative example and Example 1 is that the molecular weight of the added polypropylene glycol is greater than 2000. The mechanical properties of the obtained carbon fiber reinforced pultruded plate are shown in Table 1.

[0090] Table 1 Mechanical properties of carbon fiber reinforced pultruded sheets

[0091]

[0092] As can be seen from Table 1, the carbon fiber reinforced pultruded sheet materials of Examples 1 to 3 all have excellent tensile strength, compressive strength and shear strength, etc., which meet the requirements for use in the preparation of pultruded main beams for wind turbine blades. Compared with Example 1, Comparative Example 1 does not add aluminum hydroxide and polypropylene glycol. As can be seen from Table 1, the 0° tensile strength, 0° compressive strength and layer shear strength of Comparative Example 1 are all lower than those of Example 1, indicating that the addition of aluminum hydroxide and polypropylene glycol can improve the mechanical properties of carbon fiber reinforced pultruded sheet materials compared to Comparative Example 1. Compared with Comparative Example 1, although aluminum hydroxide is added to Comparative Example 2, polypropylene glycol is not present. Although the mechanical properties are improved to a certain extent, they are still lower than those of Example 1. This shows that the combination of aluminum hydroxide and polypropylene glycol has a significant effect on the improvement of mechanical properties. The data of Comparative Example 3 show that the addition of maleic anhydride has no obvious effect on mechanics; the aluminum hydroxide particle size in Comparative Example 4 is 5-10 μm, and its mechanics is lower than that of Example 1, indicating that the excessive particle size of aluminum hydroxide reduces the mechanical properties of the plate; Comparative Example 5 shows that the mechanics of the plate is lower than that of Example 1, suggesting that the molecular weight of polypropylene glycol affects the dispersion degree of aluminum hydroxide, thereby reducing the mechanical properties of the plate.

[0093] Table 2 Interface properties of carbon fiber reinforced pultruded sheet and infusion resin

[0094]

[0095] Compared with Example 1, Comparative Example 1 does not add aluminum hydroxide and polypropylene glycol, and Comparative Example 2 is polypropylene glycol-free. It can be seen from the interface test results in Table 2 that the tensile strength and shear strength of the splicing seams of Comparative Example 1 and Comparative Example 2 are lower than those of Example 1, indicating that compared with Comparative Example 1, the addition of polypropylene glycol can improve the bonding between the carbon fiber reinforced pultruded sheet and the infusion resin.

[0096] Compared with Example 1, Comparative Example 3 does not contain maleic anhydride. Compared with Example 1 and the other comparative examples, Comparative Example 3 has the lowest tensile strength and shear strength of the joint, indicating that maleic anhydride has a significant effect on improving the bonding between carbon fiber reinforced pultruded sheet and infusion resin.

[0097] In comparative example 4, the particle size of aluminum hydroxide is greater than 4 μm. Compared with example 1, the tensile strength and shear strength of the splicing seam are reduced. It can be seen that controlling the particle size range of aluminum hydroxide has a certain influence on the bonding between the carbon fiber reinforced pultruded plate and the infusion resin.

[0098] In comparative example 5, the molecular weight of the added polypropylene glycol is greater than 2000. Compared with example 1, the tensile strength and shear strength of the splicing seam are reduced. It can be seen that the excessive molecular weight of the polypropylene glycol also has a certain impact on the bonding between the carbon fiber reinforced pultruded plate and the infusion resin.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An epoxy resin matrix material for carbon fiber pultruded sheet, characterized by: Calculated by weight, the invention comprises 100 parts of bisphenol A epoxy resin, 105 parts of methyltetrahydrophthalic anhydride, 1-2 parts of phenol, 1-2 parts of release agent, 2-5 parts of maleic anhydride, 1-5 parts of aluminum hydroxide and 1-5 parts of polypropylene glycol.

2. The epoxy resin matrix material for carbon fiber pultruded sheet according to claim 1, characterized in that: The particle size of aluminum hydroxide is ≤4μm.

3. The epoxy resin matrix material for carbon fiber pultruded sheet according to claim 1, characterized in that: The molecular weight of polypropylene glycol is 1000.

4. The epoxy resin matrix material for carbon fiber pultruded sheet according to claim 1, characterized in that: Phenol is 2,4,6-tris(dimethylaminomethyl)phenol; The release agent is release agent INT-1890M or release agent g-172; The viscosity of bisphenol A epoxy resin is 5000-14000 mPa·s.

5. The epoxy resin matrix material for carbon fiber pultruded sheet according to claim 1, characterized in that: The acid value of methyltetrahydrophthalic anhydride is 350-700mg KOH / g.

6. A method for preparing a carbon fiber reinforced pultruded plate, characterized in that: The method comprises the following steps: impregnating carbon fiber into an epoxy resin matrix material for carbon fiber pultruded sheet material according to any one of claims 1 to 5; after impregnation, pulling the impregnated carbon fiber into a heating and curing mold, heating and curing the mold, cutting, and winding to obtain a pultruded sheet material for a pultruded main beam of a wind turbine blade.

7. The method for preparing a carbon fiber reinforced pultruded plate according to claim 6, characterized in that: In the pultruded plate, the weight fraction of carbon fiber is 64-70 parts, and the weight fraction of modified resin matrix is 30-35 parts.

8. The method for preparing a carbon fiber reinforced pultruded plate according to claim 7, characterized in that: The heating and curing mold includes a front heating and curing zone and a post heating and curing zone. The front heating and curing zone is divided into three temperature zones, and the temperatures are set to 140-150°C, 165-175°C and 185-195°C respectively; the post heating and curing zone is divided into four temperature zones, and the temperatures are set to 60-190°C, 140-180°C, 120-160°C and 100-140°C respectively.

9. A carbon fiber reinforced pultruded plate obtained by the preparation method of the carbon fiber reinforced pultruded plate according to any one of claims 6 to 8.

10. Use of the carbon fiber reinforced pultruded plate according to claim 9 in a pultruded main beam of a wind turbine blade.

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