Degradable epoxy-resin system material, and use, body, and composite material thereof and recovery method therefor

Abstract

The present invention belongs to the technical field of recoverable epoxy resins, and relates to a degradable epoxy-resin system material, and the use, a body, and a composite material thereof and a recovery method therefor. The degradable epoxy-resin system material comprises a first component and a second component, wherein the first component comprises a first epoxy resin and a second epoxy resin, and the second component comprises a first curing agent, a second curing agent and an accelerator. The first epoxy resin is one or a mixture of several of a glycidyl ether epoxy resin and a glycidyl amine epoxy resin, and the mass content thereof is 15-35% of the first component. The second epoxy resin is selected from one or more epoxy resins, the structure of which comprises (I), and the mass content thereof is 60-80% of the first component. The first curing agent is one or a mixture of several of alicyclic amines, and the mass content thereof is 40-60% of the second component. The second curing agent is one or a mixture of several of polyether amines, and the mass content thereof is 40-60% of the second component. The accelerator accounts for 0.5-3% of the second component. The present invention can satisfy requirements of the vacuum infusion of wind turbine blades.

Description

Biodegradable epoxy resin systems and their applications, main body, composite materials and their recycling methods Technical Field

[0001] This invention belongs to the field of recyclable epoxy resin technology, and particularly relates to a biodegradable epoxy resin system material and its uses, the main body, the composite material and its recycling method. Background Technology

[0002] Wind energy is a typical clean natural energy source. Converting wind energy into electricity through wind turbine generators effectively utilizes wind power, reduces the use of fossil fuels, and plays a crucial role in achieving carbon neutrality. Mass installation of wind power in my country began in 2004, reaching its peak in 2020. However, the design life of wind turbine generators is generally 20-25 years, meaning that from 2024 onwards, a large number of wind turbine generators will need to be replaced. Therefore, the rational and scientific recycling and reuse of the composite materials from the retired wind turbine blades has become a key issue for the development of the wind power renewable energy industry.

[0003] Currently, the main methods for recycling and reusing retired wind turbine blades include mechanical crushing, pyrolysis, and chemical degradation. Mechanical crushing involves cutting and grinding the composite materials from the wind turbine blades into powder for use in building materials and composite material additives. However, due to immature recycling equipment technology, low efficiency, the inability of recycled fiber quality to meet downstream product requirements, and severe dust emissions and noise pollution, sustainable development is not possible. Pyrolysis involves heating the thermosetting resin molecular chains of the organic components in the wind turbine blade composite materials to break them down into multi-component small molecule gases or liquids, separating and recovering fibers and fillers. However, pyrolysis production lines are relatively expensive, and the recovery of reinforcing materials such as glass fiber is difficult to generate high economic value. Pyrolysis is mainly used for carbon fiber reinforced composite materials with high residual value. Chemical degradation involves using solvents, temperature, and / or pressure to break down polymers at specific bond sites, forming long-chain monomers or resin raw materials. This method can simultaneously recover reinforcing materials and resin components with minimal damage to fibers, truly achieving a circular economy.

[0004] Introducing dynamic covalent bonds into the resin structure is the most direct and effective method to achieve chemical degradation. However, existing methods involve synthesizing / modifying epoxy resins or curing agents and then adding them to the formulation. For example, CN114195984A discloses a bisphenol A type epoxy curing agent containing dynamic enamine bonds and a biodegradable epoxy resin, as well as its preparation, reshaping, and degradation methods. This method synthesizes a bisphenol A type epoxy curing agent containing dynamic enamine bonds and utilizes the breaking of enamine bonds under acidic conditions to achieve resin degradation. However, the curing agent has a large molecular weight and high viscosity, and the enamine bonds are unstable and sensitive to acid. Since acidic conditions are very common in the natural environment, the performance of the cured product in actual use is difficult to directly meet requirements. CN106832767B discloses a fiber-reinforced vacuum infusion resin... The degradable epoxy resin composition uses degradable aliphatic amine curing agent ACV-1001 and degradable cycloaliphatic amine curing agent ACV-1005 as curing agents. Degradation is achieved by breaking the ketal structure under acidic conditions. Like the enamine bond, the structure is unstable and very sensitive to acid. The performance of the cured product in actual use is difficult to meet the requirements. CN115594949A discloses a recyclable epoxy wind turbine blade material and its preparation and recycling methods. The curing agent is an aromatic curing agent containing disulfide bonds. The blade material is recycled by breaking the disulfide bonds. However, the aromatic curing agent used in this method is a solid and is difficult to disperse in the resin. It requires the use of solvents, which makes the process complicated. Moreover, the curing temperature of the aromatic curing agent is higher than that of the existing wind turbine blade curing temperature.

[0005] In summary, the existing technical routes are generally complex and costly. The modified epoxy resin or curing agent has a significant impact on the performance of the blade. In addition, the modified resin system is difficult to meet the requirements of vacuum infusion during the preparation of wind turbine blade composite materials. Problems such as excessively high resin viscosity or excessively rapid viscosity increase at low temperatures, poor fiber wetting performance during infusion, and high post-curing temperature exist. Summary of the Invention

[0006] The purpose of this invention is to provide a biodegradable epoxy resin system material and its uses, the main body, the composite material and its recycling method, to solve the above problems. It can meet the requirements of low viscosity, slow reaction rate and high glass transition temperature of the cured product for vacuum infusion of wind turbine blades, and the degradation conditions are mild and do not cause significant damage to the properties of the recycled material.

[0007] In a first aspect, the present invention provides a biodegradable epoxy resin system material, comprising a first component and a second component, wherein the first component comprises a first epoxy resin and a second epoxy resin, and the second component comprises a first curing agent, a second curing agent and an accelerator;

[0008] The first epoxy resin is one or a mixture of several of glycidyl ether epoxy resins and glycidyl amine epoxy resins, and its mass content accounts for 15%-35% of the first component.

[0009] The second epoxy resin is selected from one or more structures containing The epoxy resin, wherein R is one or more of the following structures: C1-C18 aliphatic carbon chain, benzene ring and its derivatives, and heterocyclic structure and its derivative containing oxygen, nitrogen, silicon, phosphorus, sulfur or selenium elements; R1 is selected from at least one structure of methylene and cyclohexyl; R2 and R3 are each independently one or more of the following structures: hydrogen atom, C1-C18 aliphatic carbon chain, benzene ring and its derivatives, and structure containing carboxyl, hydroxyl, aldehyde or epoxy group; and the mass content of the second epoxy resin accounts for 60%-80% of the first component.

[0010] The first curing agent is one or more of alicyclic amines, and its mass content accounts for 40%-60% of the second component;

[0011] The second curing agent is one or more of polyetheramines, and its mass content accounts for 40%-60% of the second component;

[0012] The accelerator accounts for 0.5%-3% of the second component by mass.

[0013] Optionally, it has at least one of the following features:

[0014] The mass ratio of the first component to the second component is 100:(25-45);

[0015] The glycidyl ether epoxy resin includes one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and bisphenol S type epoxy resin;

[0016] The glycidylamine epoxy resin includes one or more selected from diglycidylaniline, N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenylmethane, N,N,N′,N′-tetra(epoxyethylenemethyl)-1,3-phenylenediamine, N-(2-methylphenyl)-N-(1,2-epoxypropyl)-epoxyethylenemethylamine, and triglycidyl-p-aminophenol;

[0017] The second epoxy resin includes one or more selected from diglycidyl hexahydrophthalic acid, diglycidyl 4,5-epoxytetrahydrophthalic acid, and diglycidyl phthalate.

[0018] The alicyclic amines include those selected from 4,4-diaminodicyclohexylmethane, isophorone diamine, 3,3'-dimethyl-4,4-didiaminodicyclohexylmethane, N-aminoethylpiperazine, etc. One or more of alkyldiamine and hydrogenated diaminodiphenylmethane;

[0019] The polyetheramine includes one or both selected from D230 and D400;

[0020] The accelerator is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, benzyl dimethylamine, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-trizabicyclo[4.4.0]dec-5-ene, and organometallic salts.

[0021] Optionally, the first component further includes a toughening agent, which is one or a mixture of several of inorganic nanoparticles, polysulfide rubber, PU prepolymer and polyether polyol, and accounts for 0%-10% of the first component by mass.

[0022] Optionally, the biodegradable epoxy resin system material has at least one of the following characteristics:

[0023] The initial mixed viscosity at 25℃ is 100-300 mPa·s;

[0024] The time for the viscosity to increase to 1000 mPa·s at 40℃ is 100-200 min;

[0025] The degree of reaction is over 95% when cured at 65-80℃ for 4-10 hours.

[0026] The glass transition temperature of a fully cured resin is above 85°C.

[0027] Secondly, the present invention proposes an application of the biodegradable epoxy resin system material as described above, wherein the biodegradable epoxy resin system material is used to prepare biodegradable epoxy resin bulk or biodegradable epoxy resin composite material using a vacuum infusion process.

[0028] Thirdly, the present invention provides a biodegradable epoxy resin body, which is prepared by mixing and curing the biodegradable epoxy resin system materials as described above. The preparation of the biodegradable epoxy resin body includes:

[0029] Weigh the first component and the second component according to the set mass ratio;

[0030] The first component and the second component are mixed and then vacuum stirred to remove bubbles, resulting in a mixture.

[0031] The mixture is poured into a mold coated with a release agent and then cured to obtain a biodegradable epoxy resin matrix.

[0032] Optionally, the step of curing the mixture after pouring it into a mold coated with a release agent includes:

[0033] Heat to 65-80℃ and hold for 6-12 hours to cure.

[0034] Alternatively, first heat to 30-40℃ for pre-reaction for 0-4 hours, then heat to 65-80℃ and maintain the temperature for curing for 6-10 hours.

[0035] Fourthly, the present invention proposes a method for recycling the biodegradable epoxy resin bulk as described above, comprising the following steps:

[0036] The biodegradable epoxy resin body is immersed in the degradation solution;

[0037] The temperature is raised to 80-120℃ to carry out the degradation reaction until the biodegradable epoxy resin is completely dissolved to obtain a solution.

[0038] The solution was subjected to vacuum distillation to separate the recovered degradation solution and the recovered degradation resin.

[0039] The degradation solution comprises one or more of amine compounds and alcohol compounds, as well as an organic amine catalyst.

[0040] Optionally, it has at least one of the following features:

[0041] The degradation solution contains amine compounds at a mass ratio of 0-96%, alcohol compounds at a mass ratio of 0-97%, and organic amine catalysts at a mass ratio of 1%-5%.

[0042] The amine compounds include one or more selected from ethylenediamine, butanediamine, hexanediamine, m-xylenediamine, isophoronediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine;

[0043] The alcohol compounds include one or more selected from methanol, ethanol, ethylene glycol, glycerol, isopropanol, and benzyl alcohol;

[0044] The organic amine catalyst is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, modified 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and amine-metal complexes.

[0045] Fifthly, the present invention proposes a biodegradable epoxy resin composite material, which is prepared by mixing the biodegradable epoxy resin system material as described above, compounding it with reinforcing materials, and then curing it.

[0046] Optionally, the reinforcing material is one or a mixture of several of glass fiber, carbon fiber, polyester fiber and polyamide fiber.

[0047] Optionally, the reinforcing material and the biodegradable epoxy resin system material are used to prepare the biodegradable epoxy resin composite material by vacuum infusion.

[0048] Optionally, the preparation steps of the biodegradable epoxy resin composite material include:

[0049] Weigh the first component and the second component according to the set mass ratio;

[0050] The first component and the second component are mixed and then vacuum stirred to remove bubbles, resulting in a mixture.

[0051] Vacuum is applied, and the mixture is then impregnated with the laid reinforcing material and cured to obtain a biodegradable epoxy resin composite material.

[0052] Optionally, the step of curing the mixture after impregnating the laid reinforcing material includes:

[0053] Heat to 65-80℃ and hold for 6-12 hours to cure.

[0054] Alternatively, first heat to 30-40℃ for pre-reaction for 0-4 hours, then heat to 65-80℃ and maintain the temperature for curing for 6-10 hours.

[0055] Sixthly, the present invention provides a method for recycling the biodegradable epoxy resin composite material as described above, comprising the following steps:

[0056] The biodegradable epoxy resin composite material is immersed in the degradation solution;

[0057] The temperature was raised to 80-120℃ for 10-48 hours to carry out the degradation reaction, resulting in a solution and recycled reinforcing material.

[0058] The recovered reinforcing material is retrieved, washed, and dried.

[0059] The solution was subjected to vacuum distillation to separate the recovered degradation solution and the recovered degradation resin.

[0060] The degradation solution comprises one or more of amine compounds and alcohol compounds, as well as an organic amine catalyst.

[0061] Optionally, it has at least one of the following features:

[0062] The degradation solution contains amine compounds at a mass ratio of 0-96%, alcohol compounds at a mass ratio of 0-97%, and organic amine catalysts at a mass ratio of 1%-5%.

[0063] The amine compounds include one or more selected from ethylenediamine, butanediamine, hexanediamine, m-xylenediamine, isophoronediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine;

[0064] The alcohol compounds include one or more selected from methanol, ethanol, ethylene glycol, glycerol, isopropanol, and benzyl alcohol;

[0065] The organic amine catalyst is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, modified 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and amine-metal complexes.

[0066] Compared with the prior art, the beneficial effects of the biodegradable epoxy resin system material and its uses, the main body, the composite material and its recycling method of the present invention are as follows:

[0067] 1) This invention uses commercially available epoxy resins and curing agents, employing glycidyl ester epoxy resins containing ester bonds as functional raw materials. Through formulation design, the biodegradable epoxy resin system, epoxy resin matrix, and epoxy resin composite materials can meet the requirements of low viscosity, slow reaction rate, and high glass transition temperature of the cured product for vacuum infusion of wind turbine blades. This is beneficial to the vacuum infusion process. At the same time, the resin and reinforcing material have good wetting properties, which can reduce production defects. Moreover, the structure of ester bonds is more stable than imine bonds, ketal bonds, etc. After reacting with the curing agent, the performance of the cured product is less affected under natural conditions and has good stability under normal use conditions. The prepared fiber-reinforced composite material has mechanical properties that are comparable to or even better than those of existing wind turbine blade products, meeting all the process performance and use performance requirements of existing wind turbine blade production and use.

[0068] 2) The recycling method of the present invention can rapidly degrade epoxy resin bulk and composite materials at low temperatures. The degradation conditions are relatively mild and can be achieved at normal pressure and 80-120°C. The equipment is simple, and there is no waste discharge during the degradation process. At the same time, the resin and reinforcing materials are recovered. The degradation and recycling process does not cause significant damage to the performance of the recovered reinforcing materials. The recovered reinforcing materials can be directly taken out, washed, dried and recycled for reuse. The degraded resin can be directly reused after being separated from the degradation liquid by vacuum distillation. Attached Figure Description

[0069] Figure 1 is a schematic flowchart of a method for recycling a biodegradable epoxy resin body according to an embodiment of the present invention.

[0070] Figure 2 is a schematic flowchart of a method for recycling biodegradable epoxy resin composite materials according to an embodiment of the present invention;

[0071] Figure 3 is a gel permeation chromatogram of the recycled and degraded resin of Example 1. Detailed Implementation

[0072] This invention proposes a biodegradable epoxy resin system comprising a first component and a second component. The first component comprises a first epoxy resin and a second epoxy resin, and the second component comprises a first curing agent, a second curing agent, and an accelerator. The first epoxy resin is one or a mixture of several glycidyl ether epoxy resins and glycidyl amine epoxy resins, and its mass content accounts for 15%-35% of the first component. The second epoxy resin is a functional epoxy resin selected from one or more structures containing... The epoxy resin comprises, wherein R is one or more of the following structures: C1-C18 aliphatic carbon chains, benzene rings and their derivatives, and heterocyclic structures and their derivatives containing elements such as oxygen, nitrogen, silicon, phosphorus, sulfur and / or selenium; R1 is selected from at least one structure of methylene and cyclohexyl; R2 and R3 are each independently a group attached to the R structure, and can be one or more of the following structures: hydrogen atom, methyl ethyl, etc., C1-C18 short aliphatic carbon chains, benzene rings and their derivatives, and structures containing carboxyl, hydroxyl, aldehyde or epoxy groups. The structures of R2 and R3 in the above chemical structural formula can be the same or different, and can be selected from the above structures; two R1s with the same structure are symmetrically arranged. The second epoxy resin accounts for 60%-80% of the mass content of the first component. The first curing agent is one or more of alicyclic amines, accounting for 40%-60% of the mass content of the second component. The second curing agent is one or more of polyether amines, accounting for 40%-60% of the mass content of the second component. The accelerator accounts for 0.5%-3% of the mass content of the second component.

[0073] Among them, glycidyl ether epoxy resins include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, etc. Glycidyl amine epoxy resins include one or more selected from diglycidyl aniline, N,N,N′,N′-tetraglycyloxypropyl-4,4′-diaminodiphenylmethane, N,N,N′,N′-tetra(epoxyethylenemethyl)-1,3-phenylenediamine, N-(2-methylphenyl)-N-(1,2-epoxypropyl)-epoxyethylenemethylamine, triglycidyl-p-aminophenol, etc. The second epoxy resin includes one or more selected from diglycidyl hexahydrophthalic acid, 4,5-epoxytetrahydrophthalic acid, diglycidyl phthalate, etc. Alicyclic amines include those selected from 4,4-diaminodicyclohexylmethane, isophorone diamine, 3,3′-didimethyl-4,4-diaminodicyclohexylmethane, N-aminoethylpiperazine, etc. One or more of alkyldiamines, hydrogenated diaminodiphenylmethane, etc. Polyetheramines include one or more selected from D230, D400, etc. The accelerator is one or a mixture of several of 2,4,6-tris(dimethylaminomethyl)phenol, benzyldimethylamine, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4,0]dec-5-ene, and organometallic salts.

[0074] In some embodiments of the present invention, the mass ratio of the first component to the second component is 100:(25-45).

[0075] In some embodiments of the present invention, the first component further includes a toughening agent, which is one or a mixture of several of inorganic nanoparticles, polysulfide rubber, PU prepolymer and polyether polyol, and the mass content accounts for 0%-10% of the first component.

[0076] The biodegradable epoxy resin system material of some embodiments of the present invention has at least one of the following characteristics:

[0077] The initial mixed viscosity at 25℃ is 100-300 mPa·s;

[0078] The time for the viscosity to increase to 1000 mPa·s at 40℃ is 100-200 min;

[0079] The degree of reaction is over 95% when cured at 65-80℃ for 4-10 hours.

[0080] The glass transition temperature of a fully cured resin is above 85°C.

[0081] Specifically, when the first and second components of the biodegradable epoxy resin system are mixed, at the curing temperature, the epoxy groups of the epoxy resin interact with the active groups of the curing agent and gradually crosslink. The aforementioned "degree of reaction" can also be called the degree of curing, which refers to the proportion of epoxy groups that have participated in the crosslinking chemical reaction to the total number of initial epoxy groups during the curing process of the first and second components of the biodegradable epoxy resin system.

[0082] The present invention also proposes a use of the biodegradable epoxy resin system material as described above, which can be used to prepare biodegradable epoxy resin bulk or biodegradable epoxy resin composite material using a vacuum infusion process.

[0083] This invention also proposes a biodegradable epoxy resin body, which is prepared by mixing and curing the biodegradable epoxy resin system materials as described above. The preparation steps include:

[0084] Weigh the first component and the second component according to the set mass ratio;

[0085] The first and second components are mixed and then vacuum stirred to remove bubbles, resulting in a mixture.

[0086] After the mixture is poured into a mold coated with a release agent, it is placed in an oven for curing to obtain a biodegradable epoxy resin matrix.

[0087] In some embodiments of the present invention, the step of curing the mixture after pouring it into a mold coated with a release agent includes:

[0088] Heat to 65-80℃ and hold for 6-12 hours to cure.

[0089] Alternatively, first heat to 30-40℃ for pre-reaction for 0-4 hours, then heat to 65-80℃ and maintain the temperature for curing for 6-10 hours.

[0090] This invention also proposes a method for recycling biodegradable epoxy resin bulk, as shown in Figure 1, comprising the following steps:

[0091] Step S101: Immerse the biodegradable epoxy resin body in the degradation solution;

[0092] Step S102: Heat to 80-120℃ and carry out reflux degradation reaction for 10-48 hours until the biodegradable epoxy resin is completely dissolved to obtain a solution. At this time, the biodegradable epoxy resin is degraded into small molecule oligomers that dissolve in the degradation solution.

[0093] Step S103: The solution is subjected to vacuum distillation at 40℃-190℃ to separate the recovered degradation solution and the recovered degradation resin.

[0094] Before immersing the biodegradable epoxy resin in the degradation solution, the resin is broken down into smaller pieces to accelerate degradation. 100g of degradation solution can typically recover and degrade 0-70g of the biodegradable epoxy resin. Complete degradation generally takes 10-48 hours. Degradation is carried out in a sealed container equipped with a condenser to allow for continuous reflux during the degradation process.

[0095] The degradation solution comprises one or more of amine compounds and alcohol compounds, as well as an organic amine catalyst. In some embodiments of the present invention, the mass percentage of amine compounds in the degradation solution is 0-96%, the mass percentage of alcohol compounds is 0-97%, and the mass percentage of organic amine catalyst is 1%-5%. The amine compounds include one or more selected from ethylenediamine, butanediamine, hexamethylenediamine, m-xylenediamine, isophoronediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. The alcohol compounds include one or more selected from methanol, ethanol, ethylene glycol, glycerol, isopropanol, and benzyl alcohol. The organic amine catalyst is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, modified 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and amine-metal complexes.

[0096] The present invention also proposes a biodegradable epoxy resin composite material, which is prepared by mixing the biodegradable epoxy resin system material as described above, compounding it with reinforcing materials, and then curing it.

[0097] The reinforcing material is one or a mixture of several of glass fiber, carbon fiber, polyester fiber and polyamide fiber.

[0098] In one embodiment of the present invention, a biodegradable epoxy resin composite material is prepared by vacuum infusion using a reinforcing material and a biodegradable epoxy resin system. The preparation steps include:

[0099] Weigh the first component and the second component according to the set mass ratio;

[0100] The first and second components are mixed and then vacuum stirred to remove bubbles, resulting in a mixture.

[0101] Vacuum is applied, and the mixture is then impregnated with the laid-up reinforcing material and cured to obtain a biodegradable epoxy resin composite material.

[0102] In some embodiments of the present invention, the step of curing the mixture after impregnating the laid reinforcing material includes:

[0103] Heat to 65-80℃ and hold for 6-12 hours to cure.

[0104] Alternatively, first heat to 30-40℃ for pre-reaction for 0-4 hours, then heat to 65-80℃ and maintain the temperature for curing for 6-10 hours.

[0105] This invention also proposes a method for recycling biodegradable epoxy resin composite materials, as shown in Figure 2, comprising the following steps:

[0106] Step S201: Immerse the biodegradable epoxy resin composite material in the degradation solution;

[0107] Step S202: Heat to 80-120℃ and carry out reflux degradation reaction for 10-48h to obtain solution and recycled reinforcing material. At this time, the biodegradable epoxy resin system material is degraded into small molecule oligomers and dissolved in the degradation solution.

[0108] Step S203: Take out the recycled reinforcing material, wash and dry it with water, rinse it three times, and dry it in an oven at 120°C for 2 hours;

[0109] Step S204: The solution is subjected to vacuum distillation at 40℃-190℃ to separate the recovered degradation solution and the recovered degradation resin.

[0110] Before immersing the biodegradable epoxy resin composite material in the degradation solution, the composite material is broken down into smaller pieces to accelerate degradation. 100g of degradation solution can typically recover and degrade 0-180g of the biodegradable epoxy resin composite material. Degradation is carried out in a sealed container equipped with a condenser to allow for continuous reflux during the degradation process.

[0111] The degradation solution comprises one or more of amine compounds and alcohol compounds, as well as an organic amine catalyst. In some embodiments of the present invention, the mass percentage of amine compounds in the degradation solution is 0-96%, the mass percentage of alcohol compounds is 0-97%, and the mass percentage of organic amine catalyst is 1%-5%. The amine compounds include one or more selected from ethylenediamine, butanediamine, hexamethylenediamine, m-xylenediamine, isophoronediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. The alcohol compounds include one or more selected from methanol, ethanol, ethylene glycol, glycerol, isopropanol, and benzyl alcohol. The organic amine catalyst is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, modified 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and amine-metal complexes.

[0112] The biodegradable epoxy resin system of the present invention can be used as a raw material to prepare biodegradable epoxy resin bulk, and can also be compounded with reinforcing materials (such as fibers, fabrics, etc.) to prepare biodegradable epoxy resin composite materials. Furthermore, both the biodegradable epoxy resin bulk and the composite materials can be manufactured using a vacuum infusion system.

[0113] It should be noted that in this application, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible secondary ranges and individual numerical values ​​(including integers and fractions) within those ranges. For the sake of brevity, not all possible combinations of the various technical features in the various embodiments or examples are described. Therefore, as long as the combinations of these technical features do not contradict each other, the various technical features in the various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification. In this invention, the sum of the percentage contents of all components contained in the composition is 100%.

[0114] To make the objectives, technical solutions, and advantages of this invention more readily understood, the invention will be further described in detail below with reference to specific embodiments. These embodiments are only some, not all, of the embodiments of this invention. It should be noted that while these embodiments illustrate many specific details to provide a thorough understanding of the invention, the invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, these specific embodiments do not constitute any limitation on the actual scope of protection of this invention, and the invention is not limited to the specific embodiments disclosed below.

[0115] In all the following examples and comparative examples, unless otherwise specified, "parts" of component amounts refer to parts by weight. In engineering, the first component is often referred to as component A and the second component as component B; therefore, the following examples will follow the engineering terminology. The biodegradable epoxy resin composites in the following examples are all prepared by vacuum infusion of reinforcing materials and biodegradable epoxy resin system materials. The infusion process determines that the content of reinforcing materials in the biodegradable epoxy resin composites is generally around 75%, with very little variation between the examples; therefore, the ratio of biodegradable epoxy resin system materials to reinforcing materials in the biodegradable epoxy resin composites will not be described in detail. Furthermore, for different reinforcing materials, the mass ratio will vary greatly due to differences in fiber density; therefore, the mass ratio of biodegradable epoxy resin system materials to reinforcing materials in the biodegradable epoxy resin composites is not a constant value.

[0116] Example 1

[0117] Prepare biodegradable epoxy resin system materials: Component A: 33 parts diglycidyl aniline, 62 parts diglycidyl hexahydrophthalic acid, 5 parts polyether polyol; Component B: 42 parts isophorone diamine, 57 parts polyether amine D230, 1 part 2,4,6-tris(dimethylaminomethyl)phenol.

[0118] Preparation of biodegradable epoxy resin body: Based on the above biodegradable epoxy resin system material, mix components A and B in a mass ratio of 100:33, stir and degas under vacuum, pour into a mold, heat to 40℃ for pre-reaction for 3 hours, then heat to 80℃ for curing for 7 hours to obtain biodegradable epoxy resin body.

[0119] Recovery of biodegradable epoxy resin bulk: First, weigh 97 parts of anhydrous ethanol and 3 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and stir until completely dissolved to obtain a degradation solution; cut the biodegradable epoxy resin bulk into 1×1×0.2cm sample blocks, weigh 10g and place them in a round-bottom flask; pour in 50ml of degradation solution, heat to 100℃ and stir for 40h, until the epoxy resin bulk is completely degraded into small molecule oligomers that dissolve in the degradation solution to obtain a solution; distill the solution under reduced pressure at 40℃ to separate the recovered degradation solution and recovered degradation resin. The resin recovery rate can reach 100%.

[0120] Preparation of biodegradable epoxy resin composite material: Based on the above biodegradable epoxy resin system material, the components A and B are mixed evenly at a mass ratio of 100:33. After vacuum stirring and degassing, a mixture is obtained. The mixture is then introduced into glass fiber cloth through vacuum. The mixture is first heated to 40°C for pre-reaction for 3 hours, and then heated to 80°C for curing for 7 hours to obtain the biodegradable epoxy resin composite material.

[0121] Recovery of biodegradable epoxy resin composite materials: First, weigh 97 parts of anhydrous ethanol and 3 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, stir until completely dissolved to obtain a degradation solution; cut the biodegradable epoxy resin composite material into 2×2×0.2cm sample blocks, weigh 20g and place them in a round-bottom flask; pour in 50ml of degradation solution, heat to 100℃ and stir for 30h, the resin is completely degraded into small molecule oligomers that dissolve in the degradation solution and separate from the reinforcing fibers to obtain a solution and recovered reinforcing material; remove the recovered reinforcing fibers from the solution, rinse three times with water, and dry in an oven at 120℃ for 2h; distill the solution under reduced pressure at 40℃ to separate the recovered degradation solution and recovered degradation resin. The recovery rate of reinforcing fibers and resin can reach 100%.

[0122] Example 2

[0123] Prepare biodegradable epoxy resin system materials: Component A: 33 parts diglycidyl aniline, 43 parts diglycidyl phthalate, 19 parts diglycidyl hexahydrophthalate, and 5 parts polyether polyol; Component B: 42 parts isophorone diamine, 57 parts polyether amine D230, and 1 part 2,4,6-tris(dimethylaminomethyl)phenol.

[0124] Preparation of biodegradable epoxy resin body: Based on the above biodegradable epoxy resin system material, mix components A and B in a mass ratio of 100:38, perform vacuum stirring to remove bubbles, pour into a mold, heat to 70℃ and keep warm for 10 hours to obtain biodegradable epoxy resin body.

[0125] Recovery of biodegradable epoxy resin bulk: First, weigh 96 parts of anhydrous ethanol and 4 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and stir until completely dissolved to obtain a degradation solution; cut the biodegradable epoxy resin bulk into 1×1×0.2cm sample blocks, weigh 10g and place them in a round-bottom flask; pour in 50ml of degradation solution, heat to 90℃ and stir for 48h, until the epoxy resin bulk is completely degraded into small molecule oligomers that dissolve in the degradation solution to obtain a solution; distill the solution under reduced pressure at 40℃ to separate the recovered degradation solution and recovered degradation resin. The resin recovery rate can reach 100%.

[0126] Preparation of biodegradable epoxy resin composite material: Based on the above biodegradable epoxy resin system material, the components A and B are mixed evenly at a mass ratio of 100:38. After vacuum stirring and degassing, a mixture is obtained. The mixture is then introduced into glass fiber cloth through vacuum and heated to 70°C for 10 hours to prepare the biodegradable epoxy resin composite material.

[0127] Recovery of biodegradable epoxy resin composite materials: First, weigh 96 parts of anhydrous ethanol and 4 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, stir until completely dissolved to obtain a degradation solution; cut the biodegradable epoxy resin composite material into 2×2×0.2cm sample blocks, weigh 20g and place them in a round-bottom flask; pour in 50ml of degradation solution, heat to 90℃ and stir for 36h, the resin is completely degraded into small molecule oligomers that dissolve in the degradation solution, separate from the reinforcing fibers, and obtain the solution and recovered reinforcing material; remove the recovered reinforcing fibers from the solution, rinse three times with water, and dry in an oven at 120℃ for 2h; distill the solution under reduced pressure at 40℃ to separate the recovered degradation solution and recovered degradation resin. The recovery rate of reinforcing fibers and resin can reach 100%.

[0128] Example 3

[0129] Prepare biodegradable epoxy resin system materials: Component A: 20 parts of triglycidyl-p-aminophenol, 80 parts of diglycidyl hexahydrophthalic acid; Component B: 58 parts of 3,3'-dimethyl-4,4-diaminodicyclohexylmethane, 41 parts of polyetheramine D230, and 1 part of 2,4,6-tris(dimethylaminomethyl)phenol.

[0130] Preparation of biodegradable epoxy resin body: Based on the above biodegradable epoxy resin system material, mix components A and B in a mass ratio of 100:41, perform vacuum stirring to remove bubbles, pour into a mold, heat to 70℃ and keep warm for 10 hours to obtain biodegradable epoxy resin body.

[0131] Recovery of biodegradable epoxy resin bulk: First, weigh 96 parts of diethylenetriamine and 4 parts of 1,8-diaza-bicyclo(5,4,0)-7-undecene, stir and dissolve evenly to obtain a degradation solution; cut the biodegradable epoxy resin bulk into 1×1×0.2cm sample blocks, weigh 10g and place them in a round-bottom flask; pour in 50ml of degradation solution, heat to 90℃ and stir for 24h, the epoxy resin bulk is completely degraded into small molecule oligomers dissolved in the degradation solution to obtain a solution; distill the solution under reduced pressure at 190℃ to separate the recovered degradation solution and recovered degradation resin. The resin recovery rate can reach 100%.

[0132] Preparation of biodegradable epoxy resin composite material: Based on the above biodegradable epoxy resin system material, the components A and B are mixed evenly at a mass ratio of 100:41. After vacuum stirring and degassing, a mixture is obtained. The mixture is then introduced into glass fiber cloth through vacuum and heated to 70°C for 10 hours to prepare the biodegradable epoxy resin composite material.

[0133] Recovery of biodegradable epoxy resin composites: First, weigh 96 parts of diethylenetriamine and 4 parts of 1,8-diaza-bicyclo(5,4,0)-7-undecene, stir and dissolve evenly to obtain a degradation solution; cut the biodegradable epoxy resin composite into 2×2×0.2cm sample blocks, weigh 20g and place them in a round-bottom flask; pour in 50ml of the degradation solution, heat to 90℃ and stir for 13h, the resin is completely degraded into small molecule oligomers that dissolve in the degradation solution and separate from the reinforcing fibers, obtaining the solution and recovered reinforcing material; remove the recovered reinforcing fibers from the solution, rinse three times with water, and dry in an oven at 120℃ for 2h; distill the solution under reduced pressure at 190℃ to separate the recovered degradation solution and recovered degraded resin. The recovery rate of reinforcing fibers and resin can reach 100%.

[0134] Example 4

[0135] Prepare biodegradable epoxy resin system materials: Component A: 9 parts triglycidyl-p-aminophenol, 24 parts diglycidyl aniline, 62 parts diglycidyl phthalate, and 5 parts polyether polyol; Component B: 45 parts isophorone diamine, 54 parts polyether amine D230, and 1 part 2,4,6-tris(dimethylaminomethyl)phenol.

[0136] Preparation of biodegradable epoxy resin body: Based on the above biodegradable epoxy resin system material, mix components A and B in a mass ratio of 100:35, stir and degas under vacuum, pour into a mold, heat to 30℃ for pre-reaction for 4 hours, then heat to 70℃ for curing for 10 hours to obtain biodegradable epoxy resin body.

[0137] Recovery of biodegradable epoxy resin bulk: First, weigh 49 parts of anhydrous ethanol, 49 parts of hexamethylenediamine, and 2 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and stir until completely dissolved to obtain a degradation solution; cut the biodegradable epoxy resin bulk into 1×1×0.2cm sample blocks, weigh 10g and place them in a round-bottom flask; pour in 50ml of the degradation solution, heat to 100℃ and stir for 21h, until the epoxy resin bulk is completely degraded into small molecule oligomers that dissolve in the degradation solution to obtain a solution; distill the solution under reduced pressure at 40℃ and 180℃ to separate the recovered degradation solution and recovered degradation resin. The resin recovery rate can reach 100%.

[0138] Preparation of biodegradable epoxy resin composite material: Based on the above biodegradable epoxy resin system material, the components A and B are mixed evenly at a mass ratio of 100:35. After vacuum stirring and degassing, a mixture is obtained. The mixture is then introduced into glass fiber cloth through vacuum. The mixture is first heated to 30°C for pre-reaction for 4 hours, and then heated to 70°C for heat preservation and curing for 10 hours to prepare the biodegradable epoxy resin composite material.

[0139] Recovery of biodegradable epoxy resin composite materials: First, weigh 49 parts of anhydrous ethanol, 49 parts of hexamethylenediamine, and 2 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and stir until completely dissolved to obtain a degradation solution; cut the biodegradable epoxy resin composite material into 2×2×0.2cm sample blocks, weigh 20g and place them in a round-bottom flask; pour in 50ml of the degradation solution, heat to 100℃ and stir for 10h, the resin is completely degraded into small molecule oligomers that dissolve in the degradation solution and separate from the reinforcing fibers, obtaining a solution and recovered reinforcing material; remove the recovered reinforcing fibers from the solution, rinse three times with water, and dry in an oven at 120℃ for 2h; distill the solution under reduced pressure at 40℃ and 180℃ to separate the recovered degradation solution and recovered degradation resin. The recovery rate of reinforcing fibers and resin can reach 100%.

[0140] Comparative Example

[0141] Taking the epoxy resin system material that is widely used in the market and has superior performance as an example, it was purchased from Daosheng Tianhe Materials Technology (Shanghai) Co., Ltd., with the brand name TECHSTORM190 / 195. It is a two-component system, with TS190 being epoxy resin and TS195 being curing agent.

[0142] Preparation of epoxy resin matrix: Daosheng Tianhe TS190 epoxy resin and Daosheng Tianhe TS195 curing agent are mixed evenly at a ratio of 100:28. After vacuum stirring and degassing, the mixture is poured into a mold, heated to 30℃ for pre-reaction for 4 hours, and then heated to 70℃ for curing for 10 hours to obtain epoxy resin matrix.

[0143] A recycling test was conducted on the epoxy resin bulk: 96 parts of hexamethylenediamine and 4 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene were weighed and stirred until completely dissolved to obtain a degradation solution; the epoxy resin bulk was cut into 1×1×0.2cm sample blocks, and 10g of each block was weighed and placed in a round-bottom flask; 50ml of degradation solution was poured in, and the temperature was raised to 100℃ and stirred for 48h. The sample blocks showed no change and were not degradable.

[0144] Preparation of epoxy resin composite material: Daosheng Tianhe TS190 epoxy resin and Daosheng Tianhe TS195 curing agent were mixed evenly at a ratio of 100:28. After vacuum stirring and degassing, a mixture was obtained. The mixture was then introduced into glass fiber cloth through vacuum. The mixture was first heated to 30℃ for pre-reaction for 4 hours, and then heated to 70℃ for heat preservation and curing for 10 hours to obtain epoxy resin composite material.

[0145] A recycling test was conducted on the epoxy resin composite material: 96 parts of hexamethylenediamine and 4 parts of 1,5,7-triazabicyclo[4.4.0]dec-5-ene were weighed and stirred until completely dissolved to obtain a degradation solution; the epoxy resin composite material was cut into 2×2×0.2cm sample blocks, and 20g of each block was weighed and placed in a round-bottom flask; 50ml of degradation solution was poured in, and the temperature was raised to 100℃ and stirred for 48h. The sample blocks showed no change and were not degradable.

[0146] The epoxy resin system material, matrix, and composite material of the above embodiments and comparative examples were tested respectively to characterize the performance of the epoxy resin system material, matrix, and composite material of the present invention.

[0147] Viscosity and viscosity growth tests were conducted on the epoxy resin system materials and components of each embodiment and comparative example according to standard DIN 53019. The test results are shown in Table 1 below. Table 1 shows that the initial mixed viscosity of the biodegradable epoxy resin system material used for vacuum infusion of wind turbine blades is 100-300 mPa·s (25℃), and the time for viscosity growth to reach 1000 mPa·s is 100-200 min (40℃). The epoxy resin system material in this invention has a low viscosity and a slow viscosity growth rate, resulting in high operability when used for vacuum infusion of wind turbine blades, which is beneficial for good wetting of the resin into the reinforcing material and the bonding between the resin and the reinforcing material.

[0148] Table 1: Viscosity and viscosity growth test results of epoxy resin system materials and components in Examples 1 to 4 and the comparative examples.

[0149] The glass transition temperature (Tg) of the epoxy resin bulk materials of each embodiment and comparative example was tested according to standard ISO 11357; the tensile properties of the epoxy resin bulk materials of each embodiment and comparative example were tested according to standard ISO 527-2; the flexural properties of the epoxy resin bulk materials of each embodiment and comparative example were tested according to standard ISO 178; and the tensile properties of the epoxy resin composite materials of each embodiment and comparative example were tested according to standard ISO 527-5. The test results are shown in Table 2 below. As can be seen from Table 2, the Tg of the epoxy resin bulk material of the present invention is higher than 85°C, and the curing temperature of the resin is lower than 80°C, making it suitable for existing wind turbine blade production equipment. The tensile strength, tensile modulus, flexural strength, and flexural modulus of the epoxy resin bulk material and vacuum-infused composite material of the present invention are all higher than those of the commercially available product TS 190 / 195. The epoxy resin bulk material and vacuum-infused composite material of the present invention are biodegradable at lower temperatures, and the reinforcing fibers and resin can be recycled simultaneously.

[0150] Table 2: Test results of glass transition temperature, tensile properties, and flexural properties of epoxy resin bulk and composite materials in Examples 1 to 4 and comparative examples.

[0151] In summary, the biodegradable epoxy resin system material, epoxy resin body, and epoxy resin composite material of the present invention can meet the requirements of low viscosity, slow reaction rate, and high glass transition temperature of cured products for vacuum infusion of wind turbine blades, which is beneficial to the vacuum infusion process. Under normal use conditions, they have good stability and mechanical properties that are comparable to or even better than those of existing conventional wind turbine blade products, and can meet all the process performance and use performance requirements of existing wind turbine blade production and use.

[0152] Taking the GPC (gel permeation chromatography) test of the recycled and degraded resin of Example 1 as an example, the performance of the recycled and degraded resin was analyzed. The chromatogram of the recycled and degraded resin of Example 1 is shown in Figure 3. As can be seen from Figure 3, the molecular weight of the recycled and degraded resin is relatively small, mainly between 200 and 1300, which is beneficial for the reuse of the degradation products. Subsequent use verification showed that the strength of the recycled reinforcing fiber of the present invention can be maintained at more than 95% of the original fiber, and the degraded resin can be directly reused as a curing agent or toughening agent, etc.

[0153] It should be noted that "an embodiment" or "an embodiment" in this application refers to a specific feature, structure, or characteristic that can be included in at least one implementation of the present invention. The phrases "in one embodiment" and "an embodiment" appearing in different places in this specification do not all refer to the same embodiment, nor are they embodiments that are mutually exclusive, either alone or selectively, with other embodiments. The terms "comprising" or "including" indicate the presence of the claimed feature but do not exclude the presence of one or more other features. The term "and / or" as used in this application includes any and all combinations of one or more of the related listed items. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0154] The present invention has the following beneficial effects:

[0155] 1) This invention uses commercially available epoxy resins and curing agents, employing glycidyl ester epoxy resins containing ester bonds as functional raw materials. Through formulation design, the biodegradable epoxy resin system, epoxy resin matrix, and epoxy resin composite materials can meet the requirements of low viscosity, slow reaction rate, and high glass transition temperature of the cured product for vacuum infusion of wind turbine blades. This is beneficial to the vacuum infusion process. At the same time, the resin and reinforcing material have good wetting properties, which can reduce production defects. Moreover, the structure of ester bonds is more stable than imine bonds, ketal bonds, etc. After reacting with the curing agent, the performance of the cured product is less affected under natural conditions and has good stability under normal use conditions. The prepared fiber-reinforced composite material has mechanical properties that are comparable to or even better than those of existing wind turbine blade products, meeting all the process performance and use performance requirements of existing wind turbine blade production and use.

[0156] 2) The recycling method of the present invention can rapidly degrade epoxy resin bulk and composite materials at low temperatures. The degradation conditions are relatively mild and can be achieved at normal pressure and 80-120°C. The equipment is simple, and there is no waste discharge during the degradation process. At the same time, the resin and reinforcing materials are recovered. The degradation and recycling process does not cause significant damage to the performance of the recovered reinforcing materials. The recovered reinforcing materials can be directly taken out, washed, dried and recycled for reuse. The degraded resin can be directly reused after being separated from the degradation liquid by vacuum distillation.

[0157] Although the methods described above are illustrated and depicted as a series of actions for the sake of simplicity, it should be understood and appreciated that these methods are not limited by the order of the actions, as some actions may occur in a different order and / or concurrently with other actions from the illustrations and descriptions herein or not illustrated and described herein but which may be understood by those skilled in the art, according to one or more embodiments.

[0158] The method steps of this application illustrated in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications (e.g., parameter values, material usage, etc.) are possible without substantially departing from the novel teachings and advantages of the subject matter described in this application. Therefore, all such modifications are intended to be included within the scope of this invention. The order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments. Various corresponding modifications and variations can be made by those skilled in the art according to this invention without departing from its spirit and essence, but all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A biodegradable epoxy resin system material, characterized in that, It includes a first component and a second component, wherein the first component includes a first epoxy resin and a second epoxy resin, and the second component includes a first curing agent, a second curing agent and an accelerator; The first epoxy resin is one or a mixture of several of glycidyl ether epoxy resins and glycidyl amine epoxy resins, and its mass content accounts for 15%-35% of the first component. The second epoxy resin is selected from one or more structures containing The epoxy resin, wherein R is one or more of the following structures: C1-C18 aliphatic carbon chain, benzene ring and its derivatives, and heterocyclic structure and its derivative containing oxygen, nitrogen, silicon, phosphorus, sulfur or selenium elements; R1 is selected from at least one structure of methylene and cyclohexyl; R2 and R3 are each independently one or more of the following structures: hydrogen atom, C1-C18 aliphatic carbon chain, benzene ring and its derivatives, and structure containing carboxyl, hydroxyl, aldehyde or epoxy group; and the mass content of the second epoxy resin accounts for 60%-80% of the first component. The first curing agent is one or more of alicyclic amines, and its mass content accounts for 40%-60% of the second component; The second curing agent is one or more of polyetheramines, and its mass content accounts for 40%-60% of the second component; The accelerator accounts for 0.5%-3% of the second component by mass.

2. The biodegradable epoxy resin system material according to claim 1, characterized in that, It has at least one of the following characteristics: The mass ratio of the first component to the second component is 100:(25-45); The glycidyl ether epoxy resin includes one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and bisphenol S type epoxy resin; The glycidylamine epoxy resin includes one or more selected from diglycidylaniline, N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenylmethane, N,N,N′,N′-tetra(epoxyethylenemethyl)-1,3-phenylenediamine, N-(2-methylphenyl)-N-(1,2-epoxypropyl)-epoxyethylenemethylamine, and triglycidyl-p-aminophenol; The second epoxy resin includes one or more selected from diglycidyl hexahydrophthalic acid, diglycidyl 4,5-epoxytetrahydrophthalic acid, and diglycidyl phthalic acid. The alicyclic amines include one or more selected from 4,4-diaminodicyclohexylmethane, isophorone diamine, 3,3′-dimethyl-4,4-diaminodicyclohexylmethane, N-aminoethylpiperazine, cyclohexane diamine and hydrogenated diaminodiphenylmethane; The polyetheramine includes one or both selected from D230 and D400; The accelerator is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, benzyl dimethylamine, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-trizabicyclo[4.4.0]dec-5-ene, and organometallic salts.

3. The biodegradable epoxy resin system material according to claim 1, characterized in that, The first component further includes a toughening agent, which is one or a mixture of several of inorganic nanoparticles, polysulfide rubber, PU prepolymer and polyether polyol, and accounts for 0%-10% of the first component by mass.

4. The use of a biodegradable epoxy resin system material as described in any one of claims 1-3, characterized in that, The biodegradable epoxy resin system material is used to prepare biodegradable epoxy resin bulk or biodegradable epoxy resin composite material using a vacuum infusion process.

5. A biodegradable epoxy resin matrix, characterized in that, The biodegradable epoxy resin body is prepared by mixing and curing the biodegradable epoxy resin system materials as described in any one of claims 1-3, wherein the preparation of the biodegradable epoxy resin body comprises: Weigh the first component and the second component according to the set mass ratio; The first component and the second component are mixed and then vacuum stirred to remove bubbles, resulting in a mixture. The mixture is poured into a mold coated with a release agent and then cured to obtain a biodegradable epoxy resin matrix.

6. The biodegradable epoxy resin matrix according to claim 5, characterized in that, The steps of pouring the mixture into a mold coated with a release agent and then curing it include: Heat to 65-80℃ and hold for 6-12 hours to cure. Alternatively, first heat to 30-40℃ for pre-reaction for 0-4 hours, then heat to 65-80℃ and maintain the temperature for curing for 6-10 hours.

7. A method for recycling the biodegradable epoxy resin bulk as described in claim 5, characterized in that, Includes the following steps: The biodegradable epoxy resin body is immersed in the degradation solution; The temperature is raised to 80-120℃ to carry out the degradation reaction until the biodegradable epoxy resin is completely dissolved to obtain a solution. The solution was subjected to vacuum distillation to separate the recovered degradation solution and the recovered degradation resin. The degradation solution comprises one or more of amine compounds and alcohol compounds, as well as an organic amine catalyst.

8. The method for recycling the biodegradable epoxy resin bulk according to claim 7, characterized in that, It has at least one of the following characteristics: The degradation solution contains amine compounds at a mass ratio of 0-96%, alcohol compounds at a mass ratio of 0-97%, and organic amine catalysts at a mass ratio of 1%-5%. The amine compounds include one or more selected from ethylenediamine, butanediamine, hexanediamine, m-xylenediamine, isophoronediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; The alcohol compounds include one or more selected from methanol, ethanol, ethylene glycol, glycerol, isopropanol, and benzyl alcohol; The organic amine catalyst is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, modified 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and amine-metal complexes.

9. A biodegradable epoxy resin composite material, characterized in that, It is prepared by mixing the biodegradable epoxy resin system material as described in any one of claims 1-3, compounding it with reinforcing materials, and then curing it.

10. The biodegradable epoxy resin composite material according to claim 9, characterized in that, The reinforcing material is one or a mixture of several of glass fiber, carbon fiber, polyester fiber and polyamide fiber.

11. The biodegradable epoxy resin composite material according to claim 9, characterized in that, The biodegradable epoxy resin composite material is prepared by vacuum infusion of the reinforcing material and the biodegradable epoxy resin system material.

12. The biodegradable epoxy resin composite material according to claim 11, characterized in that, The preparation steps of the biodegradable epoxy resin composite material include: Weigh the first component and the second component according to the set mass ratio; The first component and the second component are mixed and then vacuum stirred to remove bubbles, resulting in a mixture. Vacuum is applied, and the mixture is then impregnated with the laid reinforcing material and cured to obtain a biodegradable epoxy resin composite material.

13. The biodegradable epoxy resin composite material according to claim 12, characterized in that, The step of curing the mixture after impregnating the laid reinforcing material includes: Heat to 65-80℃ and hold for 6-12 hours to cure. Alternatively, first heat to 30-40℃ for pre-reaction for 0-4 hours, then heat to 65-80℃ and maintain the temperature for curing for 6-10 hours.

14. A method for recycling the biodegradable epoxy resin composite material as described in claim 9, characterized in that, Includes the following steps: The biodegradable epoxy resin composite material is immersed in the degradation solution; The temperature was raised to 80-120℃ for 10-48 hours to carry out the degradation reaction, resulting in a solution and recycled reinforcing material. The recovered reinforcing material is retrieved, washed, and dried. The solution was subjected to vacuum distillation to separate the recovered degradation solution and the recovered degradation resin. The degradation solution comprises one or more of amine compounds and alcohol compounds, as well as an organic amine catalyst.

15. The method for recycling the biodegradable epoxy resin composite material according to claim 14, characterized in that, It has at least one of the following characteristics: The degradation solution contains amine compounds at a mass ratio of 0-96%, alcohol compounds at a mass ratio of 0-97%, and organic amine catalysts at a mass ratio of 1%-5%. The amine compounds include one or more selected from ethylenediamine, butanediamine, hexanediamine, m-xylenediamine, isophoronediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; The alcohol compounds include one or more selected from methanol, ethanol, ethylene glycol, glycerol, isopropanol, and benzyl alcohol; The organic amine catalyst is one or a mixture of several of the following: 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7-undecene, N-aminoethylpiperazine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, modified 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and amine-metal complexes.

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