Bio-based resin matrix, bio-based resin composite material as well as preparation method and application of bio-based resin composite material
By using enzyme catalysts to catalyze the polymerization of vegetable oils and the mixing of nanocellulose, the problems of high viscosity and low modulus in bio-based resin composites have been solved, enabling the preparation of high-performance bio-based resin composites suitable for wind turbine blades.
Patent Information
- Application Number
- CN202511600729.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-04
- Publication Date
- 2026-01-30
AI Technical Summary
Existing bio-based resin composite materials suffer from high viscosity, low modulus, and poor water resistance, which limits their large-scale application in the field of wind turbine blades.
A bio-based resin matrix was prepared by using an enzyme catalyst to catalyze the polymerization reaction of vegetable oils. This matrix was then mixed with nanocellulose to form a continuous nanoscale network structure, which enhanced the mechanical properties and water resistance of the material.
The viscosity of the resin was reduced, the tensile modulus was increased, the water resistance of the material was improved, the performance requirements of wind turbine blades were met, and carbon emissions throughout the entire life cycle were reduced.
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Figure CN121428028A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wind power materials technology, specifically to a bio-based matrix, a bio-based resin composite material, and their preparation methods and applications. Background Technology
[0002] In the wind power sector, wind turbine blades, as the core component of wind turbine units, play a decisive role in the unit's power generation efficiency and service life due to their material properties. Currently, the mainstream blade material is mainly glass fiber reinforced petroleum-based epoxy resin. However, petroleum-based raw materials rely on non-renewable resources and generate high carbon emissions during production, which is inconsistent with the concept of sustainable development. Existing technologies often use bio-based resins to replace glass fiber reinforced petroleum-based epoxy resins. While bio-based resins can replace petroleum-based raw materials to some extent, they also have many problems. Traditional bio-based resins have excessively high room temperature viscosity, making them difficult to adapt to existing vacuum infusion equipment and causing inconvenience in production. At the same time, their composite materials have low modulus and poor water resistance, resulting in high mass loss rates in humid environments. These defects severely limit their large-scale application in the wind turbine blade field.
[0003] To address the issue of excessively high viscosity in bio-based resins, existing technologies often employ high-temperature polymerization or the addition of large amounts of diluents. However, high temperatures can lead to resin degradation, affecting resin performance; while adding diluents reduces the mechanical properties of the composite material, neither of which are ideal solutions. To improve the performance of composite materials, carbon fiber reinforcement is frequently used, but carbon fiber is expensive and has poor compatibility with bio-based resins, hindering its widespread application.
[0004] Therefore, developing a bio-based resin composite material with low viscosity, high modulus, and excellent water resistance is a technical problem that urgently needs to be solved in this field. Summary of the Invention
[0005] This invention provides a bio-based matrix to solve the problems of high resin viscosity, low modulus, and poor water resistance in existing bio-based resin composite materials.
[0006] The present invention also provides a bio-based resin composite material comprising the above-described bio-based matrix.
[0007] In a first aspect, the present invention provides a method for preparing a bio-based resin matrix, comprising the following steps: Under the action of a catalyst, the vegetable oil undergoes a polymerization reaction until the viscosity at room temperature is <500cp, thus obtaining the bio-based resin matrix; The catalyst includes an enzyme catalyst.
[0008] In one alternative embodiment, the enzyme catalyst includes at least one of lipase, carboxylesterase, and acetylesterase.
[0009] In one alternative embodiment, the mass ratio of the vegetable oil to the catalyst is 100:0.8-1.2.
[0010] In one optional embodiment, the polymerization reaction is carried out at a temperature of 40°C-60°C for 8-12 hours.
[0011] In one alternative implementation, the step of adjusting the pH to 7-8 is also included.
[0012] In one alternative embodiment, the vegetable oil includes at least one of castor oil, flaxseed oil, and rapeseed oil.
[0013] In a second aspect, the present invention provides a bio-based resin matrix prepared by the preparation method described in the first aspect.
[0014] Thirdly, the present invention provides a bio-based resin composite material, comprising a bio-based resin matrix and nanocellulose; The bio-based resin matrix is either the bio-based resin matrix prepared by the preparation method described in the first aspect or the bio-based resin matrix described in the second aspect.
[0015] In one optional embodiment, the mass ratio of the bio-based resin matrix to the nanocellulose is 1:0.03-0.08.
[0016] In one optional embodiment, the nanocellulose has a length of 5nm-800nm and a diameter of 3nm-35nm.
[0017] In one optional embodiment, the bio-based resin has a tensile modulus ≥3.5 GPa and a mass loss rate ≤0.8% after being placed in an 80% humidity environment for 30 days.
[0018] Fourthly, the present invention provides a method for preparing the bio-based resin composite material described in the third aspect, comprising the following steps: mixing the bio-based resin matrix and the nanocellulose to obtain the composite material.
[0019] Fifthly, the present invention provides an application of the bio-based resin composite material described in the third aspect or the bio-based resin composite material described in the fourth aspect in wind power materials.
[0020] The technical solution of this invention has the following advantages: 1. The bio-based resin composite material provided by this invention comprises a bio-based resin matrix and nanocellulose; the bio-based resin matrix is prepared by polymerizing vegetable oil under the action of an enzyme catalyst; the enzyme catalysis-nano-reinforcement synergistic technology is used to simultaneously solve the problems of high viscosity of bio-based resin and high modulus and poor water resistance of composite materials; specifically, this invention uses an enzyme catalyst, the reaction conditions are relatively mild, the growth rate of resin molecular chains is controllable, and the viscosity will not increase rapidly due to excessively vigorous reaction; the introduction of nanocellulose has the effect of enhancing the mechanical properties of materials, reducing viscosity by more than 40% at room temperature and increasing tensile modulus by more than 20%; on the other hand, nanocellulose has a large specific surface area, which can form a stronger interfacial bonding force when in contact with the bio-based resin matrix; and its high crystallinity allows it to be uniformly dispersed in the bio-based resin matrix, forming a continuous nanoscale network structure that prevents water molecules from penetrating. Attached Figure Description
[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0022] Figure 1 This is a process flow diagram of the preparation method of the bio-based resin composite material according to an embodiment of the present invention. Detailed Implementation
[0023] The following embodiments are provided to better understand the present invention, but the following embodiments do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the scope of protection of the present invention.
[0024] Unless otherwise specified, all experimental steps or conditions in the examples were performed according to conventional experimental procedures and conditions in the art. Reagents or instruments whose manufacturers are not specified are all commercially available products.
[0025] To address the problems existing in the aforementioned related technologies, according to a first aspect of the present invention, a method for preparing a bio-based resin matrix is provided, comprising the following steps: Under the action of a catalyst, the vegetable oil undergoes a polymerization reaction until the viscosity at room temperature is <500cp, thus obtaining the bio-based resin matrix; The catalyst includes an enzyme catalyst.
[0026] In one optional embodiment, the enzyme catalyst includes at least one of lipase, carboxylesterase, and acetylesterase, preferably lipase.
[0027] In one alternative embodiment, the mass ratio of the vegetable oil to the catalyst is 100:0.8-1.2.
[0028] It should be noted that by controlling the mass ratio of vegetable oil to catalyst to be 100:0.8-1.2, the viscosity of the bio-based resin matrix can be controlled to be <500 cP.
[0029] It should be noted that the present invention also includes a vacuum distillation step of the vegetable oil to remove impurities and free fatty acids, thereby obtaining refined plant-based raw materials. In the vacuum distillation step, the vacuum degree is 0.08MPa-0.09MPa, the temperature is 120℃-150℃, and the time is 2h-3h.
[0030] In one optional embodiment, the polymerization reaction is carried out at a temperature of 40°C-60°C for 8-12 hours.
[0031] In one alternative implementation, the step of adjusting the pH to 7-8 is also included.
[0032] In one alternative embodiment, the vegetable oil includes at least one of castor oil, flaxseed oil, and rapeseed oil.
[0033] In a second aspect, the present invention provides a bio-based resin matrix prepared by the preparation method described in the first aspect.
[0034] Thirdly, the present invention provides a bio-based resin composite material, comprising a bio-based resin matrix and nanocellulose; The bio-based resin matrix is either the bio-based resin matrix prepared by the preparation method described in the first aspect or the bio-based resin matrix described in the second aspect.
[0035] It should be noted that nanocellulose is prepared by chemical pretreatment and mechanical grinding of wood pulp fibers. Specifically, the wood pulp fibers are pretreated with a 5wt%-10wt% NaOH solution at 80℃-90℃ for 2h-3h, washed until neutral, and then ground with a ball mill for 0.5h-6h, preferably 3h, to obtain nanocellulose.
[0036] In one optional embodiment, the mass ratio of the bio-based resin matrix to the nanocellulose is 1:0.03-0.08.
[0037] In one optional embodiment, the nanocellulose has a length of 5nm-800nm and a diameter of 3nm-35nm.
[0038] It should be noted that the present invention controls the length of the nanocellulose to be 5nm-800nm and the diameter to be 3nm-35nm, making it less prone to agglomeration and able to be uniformly dispersed in the bio-based resin composite material, thereby improving the mechanical properties of the bio-based resin composite material. If the length or diameter is too large, the macroscopic size of the nanocellulose increases, the van der Waals forces between particles are enhanced, and ultrasonic dispersion is difficult to break up the agglomeration, which will form blocky or flocculent aggregates in the resin, affecting the uniformity of subsequent vacuum infusion. If the length or diameter is too small, the specific surface area of the nanocellulose will increase excessively, the surface energy will rise sharply, and "secondary agglomeration" will occur more easily, resulting in uneven dispersion, destroying the continuity of the resin matrix, and affecting the mechanical properties of the composite material.
[0039] In one optional embodiment, the bio-based resin composite material has a tensile modulus ≥3.5 GPa and a mass loss rate ≤0.8% after being placed in an 80% humidity environment for 30 days.
[0040] Fourthly, the present invention provides a method for preparing the bio-based resin composite material described in the third aspect, comprising the following steps: mixing the bio-based resin matrix and the nanocellulose to obtain the composite material.
[0041] It should be noted that the mixing method is ultrasonic treatment, and the dispersion power of the ultrasonic treatment is 300W-500W, and the time is 15min-30min.
[0042] Fifthly, the present invention provides an application of the bio-based resin composite material described in the third aspect or the bio-based resin composite material described in the fourth aspect in wind power materials.
[0043] It should be noted that the bio-based resin composite material is combined with glass fiber or carbon fiber through a vacuum infusion process and cured at 120℃-160℃ and 0.1MPa-0.5MPa for 2h-4h to prepare the load-bearing structural component of the wind turbine blade.
[0044] In this invention, the bio-based resin composite material does not require modification of existing vacuum infusion equipment, the resin injection efficiency is on par with petroleum-based resin, and it has strong production compatibility, which is conducive to its promotion and application on existing production lines.
[0045] In the bio-based resin composite material of this invention, the bio-based matrix content accounts for ≥90%, reducing carbon emissions by more than 30% throughout its entire life cycle. Furthermore, the fibers can be recovered through enzymatic hydrolysis after the wind turbine is decommissioned, further reducing environmental pollution and meeting the requirements of green development. Moreover, the raw material cost is basically the same as that of petroleum-based resins, and the performance meets blade material standards, enabling large-scale application and achieving a win-win situation for both economic and environmental benefits while ensuring performance.
[0046] The present invention will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed by the present invention.
[0047] Example 1 like Figure 1 As shown, this embodiment provides a method for preparing a bio-based resin composite material, including the following steps: (1) Weigh 1500g of castor oil, filter to remove impurities, and then distill under reduced pressure at 0.085MPa and 135℃ for 2.5h to obtain refined castor oil raw material; (2) Add 1000g of refined castor oil to the reactor, add 10g of lipase as a catalyst, control the reactor temperature at 50℃, adjust the pH value to 7.5 using NaH2PO4 buffer, and react for 10h; during the reaction, use a rotational viscometer to monitor the viscosity in real time, and stop the reaction when the viscosity reaches 450cP to obtain the bio-based resin matrix. (3) The wood pulp fiber was treated with 8wt% NaOH solution at 85℃ for 2.5h, washed until neutral, and then ground in a ball mill for 3h to obtain nanocellulose with a length of 150nm-400nm and a diameter of 8nm-15nm. 30g of nanocellulose was weighed and added to 1000g of bio-based resin semi-finished product. It was ultrasonically dispersed at 400W for 30min to make the nanocellulose uniformly dispersed in the resin. The residue of small molecules and water was removed by vacuum distillation to obtain bio-based resin composite material.
[0048] Example 2 like Figure 1 As shown, this embodiment provides a method for preparing a bio-based resin composite material, including the following steps: (1) Weigh 1500g of flaxseed oil, filter to remove impurities, and then distill under reduced pressure at 0.08MPa and 150℃ for 2h to obtain refined flaxseed oil raw material; (2) Add 1000g of refined flaxseed oil to the reaction vessel, add 8g of lipase as a catalyst, control the temperature of the reaction vessel at 60℃, adjust the pH value to 7 using NaH2PO4 buffer, and react for 8h; during the reaction, use a rotational viscometer to monitor the viscosity in real time, and stop the reaction when the viscosity reaches 450cP to obtain the bio-based resin matrix. (3) The wood pulp fiber was treated with 5wt% NaOH solution at 90℃ for 2h, washed until neutral, and then ground in a ball mill for 6h to obtain nanocellulose with a length of 80nm-300nm and a diameter of 3nm-15nm; 50g of nanocellulose was weighed and added to 1000g of bio-based resin semi-finished product, and ultrasonically dispersed at 300W for 20min to make the nanocellulose uniformly dispersed in the resin. The residual small molecules and water were removed by vacuum distillation to obtain bio-based resin composite material.
[0049] Example 3 like Figure 1 As shown, this embodiment provides a method for preparing a bio-based resin composite material, including the following steps: (1) Weigh 1500g of rapeseed oil, filter to remove impurities, and then distill under reduced pressure at 0.09MPa and 120℃ for 3h to obtain refined rapeseed oil raw material; (2) Add 1000g of refined rapeseed oil to the reaction vessel, add 12g of lipase as a catalyst, control the temperature of the reaction vessel at 40℃, adjust the pH value to 8 using NaH2PO4 buffer, and react for 12h; during the reaction, use a rotational viscometer to monitor the viscosity in real time, and stop the reaction when the viscosity reaches 450cP to obtain the bio-based resin matrix. (3) The wood pulp fiber was treated with 10wt% NaOH solution at 80℃ for 3h, washed until neutral, and then ground in a ball mill for 0.5h to obtain nanocellulose with a length of 500nm-800nm and a diameter of 20nm-35nm; 80g of nanocellulose was weighed and added to 1000g of bio-based resin matrix, and ultrasonically dispersed at 500W for 15min to make the nanocellulose uniformly dispersed in the resin. The residual small molecules and water were removed by vacuum distillation to obtain bio-based resin composite material.
[0050] Example 4 like Figure 1 As shown, this embodiment provides a method for preparing a bio-based resin composite material, including the following steps: (1) Weigh 1500g of flaxseed oil, filter to remove impurities, and then distill under reduced pressure at 0.083MPa and 125℃ for 2h to obtain refined flaxseed oil raw material; (2) Add 1000g of refined flaxseed oil to the reaction vessel, add 10g of carboxylesterase as a catalyst, control the temperature of the reaction vessel at 55℃, adjust the pH value to 7 using NaH2PO4 buffer, and react for 9h; during the reaction, use a rotational viscometer to monitor the viscosity in real time, and stop the reaction when the viscosity reaches 450cP to obtain the bio-based resin matrix. (3) The wood pulp fiber was treated with 6wt% NaOH solution at 90℃ for 2h, washed until neutral, and then ground in a ball mill for 5h to obtain nanocellulose with a length of 100nm-200nm and a diameter of 5nm-15nm; 40g of nanocellulose was weighed and added to 1000g of bio-based resin semi-finished product, and ultrasonically dispersed at 300W for 20min to make the nanocellulose uniformly dispersed in the resin. The residual small molecules and water were removed by vacuum distillation to obtain bio-based resin composite material.
[0051] Example 5 like Figure 1 As shown, this embodiment provides a method for preparing a bio-based resin composite material, including the following steps: (1) Weigh 1500g of rapeseed oil, filter to remove impurities, and then distill under reduced pressure at 0.087MPa and 140℃ for 3h to obtain refined rapeseed oil raw material; (2) Add 1000g of refined rapeseed oil to the reaction vessel, add 10g of acetylesterase as a catalyst, control the temperature of the reaction vessel at 45℃, adjust the pH value to 8 using NaH2PO4 buffer, and react for 11h; during the reaction, use a rotational viscometer to monitor the viscosity in real time, and stop the reaction when the viscosity reaches 450cP to obtain the bio-based resin matrix. (3) The wood pulp fiber was treated with 8wt% NaOH solution at 80℃ for 3h, washed until neutral, and then ground in a ball mill for 2h to obtain nanocellulose with a length of 200nm-400nm and a diameter of 10nm-20nmnm; 60g of nanocellulose was weighed and added to 1000g of bio-based resin matrix, and ultrasonically dispersed at 450W for 20min to make the nanocellulose uniformly dispersed in the resin. The residual small molecules and water were removed by vacuum distillation to obtain bio-based resin composite material.
[0052] Comparative Example 1 This comparative example provides a method for preparing a bio-based resin material, comprising the following steps: (1) Weigh 1500g of castor oil, filter to remove impurities, and then distill under reduced pressure at 0.085MPa and 135℃ for 2.5h to obtain refined castor oil raw material; (2) 1000g of refined castor oil was added to the reactor, and 10g of NaOH was added under high temperature (180℃) and high pressure (5MPa) for 10h to carry out the polymerization reaction to obtain bio-based resin material. The viscosity increased sharply within the same time as in Example 1, and reached 820cP after 10h, and continued to increase in the later stage.
[0053] Comparative Example 2 This comparative example provides a method for preparing a bio-based resin composite material, comprising the following steps: (1) Weigh 1500g of castor oil, filter to remove impurities, and then distill under reduced pressure at 0.085MPa and 135℃ for 2.5h to obtain refined castor oil raw material; (2) 1000g of refined castor oil was added to the reactor, and 10g of NaOH and KOH were added under high temperature (180℃) and high pressure (5MPa) to carry out polymerization reaction for 10h to obtain bio-based resin material; the viscosity increased sharply within the same time as in Example 1, and the viscosity reached 820cP after 10h, and continued to increase in the later stage. (3) The wood pulp fiber was treated with 8wt% NaOH solution at 85℃ for 2.5h, washed until neutral, and then ground in a ball mill for 3h to obtain nanocellulose with a length of 150nm-400nm and a diameter of 8nm-15nm. 30g of nanocellulose was weighed and added to 1000g of bio-based resin semi-finished product. The nanocellulose was ultrasonically dispersed at 400W for 30min to disperse the nanocellulose in the resin. The residue of small molecules and water was removed by vacuum distillation to obtain bio-based resin composite material.
[0054] Comparative Example 3 This comparative example provides a method for preparing a bio-based resin material, comprising the following steps: (1) Weigh 1500g of castor oil, filter to remove impurities, and then distill under reduced pressure at 0.085MPa and 135℃ for 2.5h to obtain refined castor oil raw material; (2) Add 1000g of refined castor oil to the reactor, add 10g of lipase as a catalyst, control the reactor temperature at 50℃, adjust the pH value to 7.5 using NaH2PO4 buffer, and react for 10h. During the reaction, use a rotational viscometer to monitor the viscosity in real time. When the viscosity reaches 450cP, stop the reaction to obtain bio-based resin material.
[0055] Comparative Example 4 This comparative example provides a method for preparing a bio-based resin composite material, comprising the following steps: (1) Weigh 1500g of castor oil, filter to remove impurities, and then distill under reduced pressure at 0.085MPa and 135℃ for 2.5h to obtain refined castor oil raw material; (2) Add 1000g of refined castor oil to the reactor, add 10g of NaOH as a catalyst, control the reactor temperature at 50℃, adjust the pH value to 7.5 using NaH2PO4 buffer, and react for 10h.
[0056] This reaction cannot produce a bio-based resin matrix. The traditional chemical catalyst NaOH exhibits extremely low catalytic activity under mild conditions of 50°C, failing to effectively break the ester bonds in castor oil and initiate polymerization. Consequently, the resin molecular chains cannot grow normally. Furthermore, due to insufficient activity, the reaction system often experiences only trace amounts of transesterification, failing to form a resin matrix with a certain molecular weight, viscosity, and structural stability. The final product is a mixture of unpolymerized or insufficiently polymerized castor oil.
[0057] Experimental Example 1 Viscosity and modulus tests were performed on the bio-based resin composite materials prepared in Examples 1-5 and Comparative Example 2, as well as the bio-based resin materials prepared in Comparative Examples 1 and 3. Mass tests were also performed before and after placing the materials in an environment with 80% humidity for one month, and the mass loss rate was calculated. The results are shown in Table 1. The mass loss rate is calculated as (m1-m2) / m1×100%, where m1 represents the mass of the bio-based resin composite material before placing it in an environment with 80% humidity for one month, and m2 represents the mass of the bio-based resin composite material after placing it in an environment with 80% humidity for one month.
[0058] Table 1. Viscosity test results of bio-based resin materials prepared in each embodiment and comparative example.
[0059] As shown in Table 1, the bio-based resin composite materials prepared in Examples 1-5 of this invention have low viscosity (455 cP-485 cP) and high tensile modulus (3.2 GPa-3.8 GPa). Furthermore, after being placed in an environment with 80% humidity for one month, the mass loss is only 0.3%-0.7%, demonstrating good water resistance. In contrast, the traditional chemical catalysts used in the comparative examples to catalyze castor oil easily lead to excessively high resin viscosity. Without the addition of nanocellulose, the modulus is only 2.8 GPa-3.0 GPa, and after being placed in an environment with 80% humidity for one month, the mass loss reaches a maximum of 2%. This is because traditional alkali metal hydroxide catalysts lack specificity. Under high temperature (180℃) and high pressure (5 MPa), they not only catalyze the polymerization of castor oil ester bonds but also induce random cross-linking and excessive growth of molecular chains. Unlike lipases, they cannot gently regulate the molecular chain length, leading to a sharp increase in the viscosity of the resin matrix. Furthermore, chemical catalysis leads to disordered distribution of resin molecular chains, structural defects such as breakage or excessive cross-linking, resulting in weak mechanical properties. Simultaneously, chemical catalysts are difficult to completely remove, and residual alkaline components accelerate the hydrolysis reaction of the resin under high humidity conditions. Without the addition of nanocellulose, the lack of a continuous stress transfer network formed by the nano-reinforcing phase prevents the improvement of overall rigidity through interfacial bonding, resulting in a low modulus, far below the level of the example. Additionally, the absence of nanocellulose to fill the internal voids of the resin allows water molecules to easily penetrate into the resin matrix, leading to the dissolution of a large amount of small molecules generated during hydrolysis, ultimately resulting in significant mass loss.
[0060] Experimental Example 2 The bio-based resin composites prepared in Examples 1-5 and Comparative Examples 1-3 were mixed with glass fibers at a mass ratio of 3:2. A vacuum infusion process was used to infuse the bio-based resin into the glass fiber preform under a vacuum of 0.08 MPa. The mixture was then cured at 120°C for 3 hours to prepare the bio-based composite material. According to the design requirements of the wind turbine blade, the prepared bio-based composite material was laid in a blade mold according to a specific layup pattern and cured at 150°C and 5 MPa for 2 hours to allow the layup structure to fully fuse and form a stable blade morphology, thus manufacturing the wind turbine blade. The specific layup process is as follows: First, the bio-based resin materials prepared in Examples 1-5 and Comparative Examples 1-3 are mixed with glass fibers at a mass ratio of 3:2. The resin is then fully impregnated with the glass fiber preform using a 0.08MPa vacuum infusion process, followed by curing at 120℃ for 3 hours to obtain a bio-based composite material board with basic mechanical properties. Subsequently, the composite material board undergoes targeted layup—the leaf root region employs "0° unidirectional layup (main load-bearing) + ±45° cross layup (shear resistance) + 90° circumferential layup". The blade employs a multi-layered composite structure with "layout (crack resistance)," with the number of layup layers controlled at 15-20 to enhance load-bearing capacity. The blade body primarily uses 0° unidirectional layup (60%-70%), supplemented by a small amount of ±45° layup (30%-40%), with the number of layup layers gradually increasing from 8 to 12 depending on the blade cross-section. The blade tip region utilizes a thinner layup design, primarily using ±45° cross layup (over 80%), supplemented by 2-3 layers of 0° layup to improve fatigue resistance, with the number of layup layers controlled at 5-8. During the layup process, it is crucial to ensure tight adhesion between each layer of composite material, avoiding interlayer bubbles and wrinkles. After all layup layers are completed, the entire blade is placed into a mold.
[0061] The wind turbine blades prepared in each embodiment and comparative example were subjected to tensile strength tests according to GB / T 1447-2005 "Test Method for Tensile Properties of Fiber Reinforced Plastics", flexural strength tests according to GB / T 1449-2005 "Test Method for Bending Properties of Fiber Reinforced Plastics", impact toughness tests according to GB / T 1451-2005 "Test Method for Impact Toughness of Simply Supported Beams of Fiber Reinforced Plastics", high and low temperature cycling stability tests (-40℃~80℃, 50 cycles) according to GB / T 2572-2005 "Test Method for Average Linear Expansion Coefficient of Fiber Reinforced Plastics", UV aging resistance tests (1000h UV irradiation) according to GB / T 16422.3-2014 "Laboratory Light Source Exposure Test Methods for Plastics Part 3: Fluorescent UV Lamp", and fatigue life tests (1000h UV irradiation) according to GB / T25398-2010 "Fatigue Test Method for Wind Turbine Blades". 7The glass transition temperature (Tg) was tested according to GB / T19466.2-2004 "Differential Scanning Calorimetry (DSC) for Plastics - Part 2: Determination of Glass Transition Temperature". The results are shown in Table 2.
[0062] Table 2. Test results of wind turbine blades prepared in each embodiment and comparative example.
[0063] As can be seen from Table 2, the wind turbine blades prepared in Examples 1-5 of this invention exhibit outstanding comprehensive performance, with tensile strength reaching 365MPa-400MPa, bending strength reaching 500MPa-550MPa, and impact toughness reaching 80kJ / m. 2 -92kJ / m 2 Furthermore, after 50 cycles of high and low temperature cycling from -40℃ to 80℃, the strength retention rate exceeded 87%; after 1000 hours of UV aging, the strength retention rate exceeded 87%; and after 10... 7 The fatigue life strength retention rate under cyclic loading reached 85%-92%, and the glass transition temperature (Tg) reached 132℃-140℃, exhibiting high environmental stability, fatigue resistance, and thermal stability. However, due to the high viscosity of the bio-based resin materials prepared in Comparative Examples 1 and 2, it was difficult to uniformly impregnate the glass fibers during vacuum infusion, leading to fiber agglomeration, poor resin-fiber interfacial bonding, internal bubbles, and microcracks in the wind turbine blades. These defects significantly reduced the performance of the comparative wind turbine blades, with tensile strength of only 290-310 MPa, flexural strength of only 390-420 MPa, and a strength retention rate of less than 80% after high and low temperature cycling and UV aging. 7 Under repeated cyclic loading, the fatigue life strength retention rate is as low as 65%-68%, and the glass transition temperature drops to 115℃-120℃, which cannot meet the actual usage requirements of wind turbine blades. Comparative Example 3 omits the addition of nanocellulose, and the lack of nanocellulose reinforcement and void filling makes it difficult to uniformly impregnate the glass fiber preform during vacuum infusion.
[0064] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for the preparation of a bio-based resin matrix, characterized in that, The method comprises the following steps: The plant oil is subjected to a polymerization reaction under the action of a catalyst until the room temperature viscosity is less than 500 cp, to obtain the bio-based resin matrix; The catalyst comprises an enzyme catalyst.
2. The method of preparing a bio-based resin matrix according to claim 1, characterized in that, The enzyme catalyst comprises at least one of lipase, carboxylic acid esterase and acetyl esterase. The mass ratio of the plant oil to the catalyst is 100:0.8-1.
2.
3. The method of producing a bio-based resin matrix according to claim 1, characterized in that, The polymerization reaction is performed at a temperature of 40-60 ℃ for 8-12 h. The method further comprises a step of adjusting the pH to 7-8. The plant oil comprises at least one of castor oil, flaxseed oil and rapeseed oil.
4. A bio-based resin matrix characterized in that, The bio-based resin matrix is prepared by the method of any one of claims 1-3.
5. A bio-based resin composite material, characterized by, The bio-based resin matrix and the nanocellulose. The bio-based resin matrix is prepared by the method of any one of claims 1-3 or the bio-based resin matrix of claim 4.
6. The bio-based resin composite material according to claim 5, characterized in that, The mass ratio of the bio-based resin matrix to the nanocellulose is 1:0.03-0.
08.
7. The bio-based resin composite material according to claim 6, characterized in that, The nanocellulose has a length of 5-800 nm and a diameter of 3-35 nm.
8. The bio-based resin composite material according to any one of claims 5-7, characterized in that, The bio-based resin has a tensile modulus of greater than or equal to 3.5 GPa and a mass loss rate of less than or equal to 0.8% after being placed in an 80% humidity environment for 30 days.
9. A method for the production of a bio-based resin composite according to any one of claims 5-8, characterized in that, The method comprises the following steps: mixing the bio-based resin matrix and the nanocellulose.
10. The bio-based resin composite of any one of claims 5-8 or the bio-based resin composite of claim 9 is applied to wind power materials.