High-temperature-resistant resin system for winding prepreg tape by dry method and preparation method of high-temperature-resistant resin system

Abstract

According to the high-temperature-resistant resin system for dry-method winding of the prepreg tape and the preparation method, dicyclopentadiene phenolic epoxy and polyfunctional naphthalene ring epoxy resin are selected as matrix resin, multiple components are used for adjusting the viscosity of the system, a composite curing agent is selected for adjusting the rheological manufacturability and curing activity of the system, and the high-temperature-resistant resin system for dry-method winding of the prepreg tape is obtained. An organic / inorganic hybrid latent polyphosphazene curing agent is adopted to synergistically improve the high temperature resistance and mechanical properties of the system, and a metal phthalocyanine high-temperature-resistant modified component is adopted to further adjust the high temperature resistance and rheological properties. By adjusting the chemical structures and proportions of the resin matrix, the composite curing agent and the high-temperature-resistant modified component, a resin system with excellent high-temperature resistance and an intelligent adhesion characteristic is obtained, and the prepared prepreg tape has a yarn releasing intelligent adhesion characteristic and a winding intelligent adhesion characteristic which are adaptive to dry winding. According to the technology, the blank of a high-temperature-resistant resin material system for dry-method winding is filled up, and development and application of dry-method winding in lightweight parts in the aerospace field are powerfully promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of resin-based composite materials, and mainly relates to a high-temperature resistant resin system for dry winding prepreg tape and a preparation method thereof. Background Art

[0002] Carbon fiber composite wound rotating body structural parts are widely used in the field of lightweight parts in the aerospace field due to their light weight and high strength. Fiber winding molding is mainly divided into wet winding and dry winding. The traditional winding process is mainly based on wet winding of impregnated resin, and usually only medium and low viscosity resin systems can be used. During the winding process, it is easily affected by resin flow and yarn slippage, resulting in the resin content and finished product quality being difficult to control. Considering the harsh application environment in the aerospace field, it is necessary to further improve the high temperature resistance of the resin system, which inevitably leads to an increase in resin viscosity, making wet winding no longer applicable. Dry winding is a new process that separates impregnation from winding. It can accurately control the resin content of the wound part (within an error of ±2%), and further increase the fiber volume fraction, breaking through the performance bottleneck of composite materials. At the same time, the high viscosity resin system is suitable for the preparation of dry prepreg tapes, which facilitates the application of high temperature resistant resins with better performance in winding molding products to meet the needs of high temperature resistance in the aerospace field. However, high-temperature resistant resins often have too high a viscosity, making it difficult to perfectly cover the fiber surface during impregnation and difficult to avoid adhesion between fibers during yarn laying. Therefore, the design of high-temperature resistant resin systems for dry winding prepreg tapes requires not only attention to the high-temperature resistant molecular structure design of the material system, but also attention to the matching of material properties and process parameters.

[0003] At present, Chinese patent CN103608378B discloses a rheologically adjustable resin and preparation method, which selects a solid and liquid multi-component epoxy mixture to adjust the rheological properties of the resin system, but is only applicable to the normal and medium temperature range; Chinese patent CN113733400A discloses a dry winding prepreg preparation device and preparation process, which adopts the β-ray method to detect the glue content online and accurately control it, but the solvent preparation process used in it is difficult to avoid the solvent remaining in the resin system, so that the performance of the composite material after curing is obviously low; Chinese patent CN107901447A discloses a prepreg preheating forming carbon fiber composite rotating part winding process, which combines the prepreg slitting preparation method with the winding core mold preheating process method to solve the temperature accurate control and molding mold heating problems existing in the dry winding technology, but the slitting process inevitably damages the fiber, resulting in a decrease in the performance of the product, and the core mold preheating cannot adapt to the uniform heating under multi-layer winding, and the practical application is limited. There is no public patent for high temperature resistant resin material system for dry winding prepreg tape in the current public data. Although the above patent can provide certain guidance for the design and development of high temperature resistant resin material system for dry winding prepreg tape and the optimization of prepreg tape preparation process, it cannot realize the application of high temperature resistant resin system in dry winding. The problem of coordinated matching of "material-process" in the design of high temperature resistant resin for dry winding has always been an unresolved problem. At the same time, there is a lack of evaluation method for the "smart adhesion" characteristics of dry winding prepreg tape, which restricts the development and iteration of resin system for dry winding prepreg tape. To solve this problem, the present invention provides a high temperature resistant resin system and a preparation method for dry winding prepreg tape, guides the screening of the main resin and the curing agent according to the "structure-performance" structure-activity relationship theory, achieves synergistic enhancement of the curing activity and mechanical properties of the resin system through the designed and prepared latent polyphosphazene curing agent, and then further regulates the high temperature resistance and process rheology of the resin system by using a metal phthalocyanine high temperature modified component, constructs a complete design method of the high temperature resistant resin system for dry winding prepreg tape, and formulates a reasonable evaluation method according to the requirements of the prepreg preparation process and the application needs of dry winding to facilitate the subsequent screening and development of other resin systems, fills the gap in the design of the high temperature resistant resin material system for dry winding, and provides a matrix material for the development and application of the dry winding process in lightweight components in the aerospace field. Summary of the invention

[0004] The purpose of the present invention is to provide a high temperature resistant resin system for dry winding prepreg and a preparation method thereof. The resin matrix selects dicyclopentadiene phenolic epoxy and multifunctional naphthalene epoxy resin as the main resin, and is supplemented with a multi-component epoxy resin to adjust the viscosity and viscosity of the system. A composite curing agent is selected to adjust the viscosity and curing activity of the resin system. An organic / inorganic hybrid latent polyphosphazene is used as a secondary curing agent component to adjust the high temperature resistance and room temperature latency of the system. End amino metal phthalocyanine is used as a high temperature resistant modification component. The application of the resin system in the preparation of prepreg is realized by dynamically matching material-process parameters. Dicyclopentadiene-type phenolic epoxy and multifunctional naphthalene epoxy resins are selected as the main resins to ensure basic performance, and multiple component resins are selected to regulate the viscosity and stickiness of the resin matrix, including glycidylamine type, hydantoin type, silicone modified epoxy resin, etc.; composite curing agents are selected to ensure the mechanical properties of the resin after curing, and low-viscosity high-temperature resistant aromatic amines and alicyclic amines are used as the main body to ensure the high-temperature resistance of the curing system. The secondary curing agent uses alicyclic or aromatic diisocyanate-terminated latent polyphosphazene, which has good room temperature latency; terminal amino metal phthalocyanine is selected as a high-temperature resistant modification component to further optimize the high-temperature resistance and process performance of the resin system. Through the deployment of the above components, combined with the dynamic optimization and matching of the preparation process parameters, the precise design and successful preparation of the high-temperature resistant resin system for dry winding prepreg tapes are achieved.

[0005] The solution adopted by the present invention to solve the technical problem is:

[0006] A high temperature resistant resin system for dry winding prepreg tape consists of a resin matrix, a composite curing agent and a high temperature resistant modified component.

[0007] Preferably, the high temperature resistant resin system for the dry winding prepreg tape has the following formula: 100 parts of resin matrix, 10-50 parts of composite curing agent, and 1-15 parts of high temperature resistant modified component.

[0008] Optionally, the resin matrix is ​​composed of a main resin and a component resin, wherein the main resin is 60-100 parts and the component resin is 10-50 parts, the main resin is a mixture of one or more of dicyclopentadiene-type phenolic epoxy resin and multifunctional naphthalene-ring epoxy resin, and the component resin is a mixture of one or more of glycidylamine-type, hydantoin-type, and silicone-modified epoxy resin. The dicyclopentadiene-type phenolic epoxy resin is a new type of special epoxy resin obtained by polycondensation and epoxidation of dicyclopentadiene and phenol and its derivatives. It can give the resin properties such as high adhesion and high fluidity while exerting the high temperature resistance of the phenolic resin, which helps to adjust the viscosity and stickiness of the resin system and make the prepreg process more complete; the molecular structure of the multifunctional naphthalene-ring epoxy resin contains a naphthalene ring and two or more epoxy groups, has high thermal stability and high temperature mechanical properties, and can further improve the comprehensive high temperature resistance of the resin matrix; the glycidylamine-type epoxy resin is the same as the common Compared with glycidyl ether epoxies, the carbon-oxygen bond is replaced by a carbon-nitrogen bond, which significantly improves its high-temperature resistance. Hydantoin epoxy resin is a new type of special epoxy resin with a hydantoin heterocycle obtained by glycidylating hydantoin or its derivatives. The hydantoin heterocycle structure gives it excellent electrical insulation, high temperature resistance, weather resistance and wear resistance. Silicone-modified epoxy resin is a special epoxy resin with a flexible silicon-oxygen structure obtained by physically blending or chemically grafting epoxy resin with a siloxane structure. It can not only improve the resin's high temperature resistance, weather resistance and flexibility, but also reduce the internal stress of the system. Preferably, poly[(phenyl glycidyl ether)-co-dicyclopentadiene] (epoxy equivalent of 270-300 g / eq) and naphthalene diamine tetraepoxy (epoxy equivalent of 120-170 g / eq) with excellent high temperature resistance are used as the main resin, and tetraglycidyl diaminodiphenylmethane (epoxy equivalent of 110-125 g / eq), 5,5'-dimethyl-1,3-di(oxiranylmethyl)imidazolidine-2,4-dione (epoxy equivalent of 153-154 g / eq), 5,5'-dimethyl-1,3-di(2-oxiranyl-ethoxymethyl)imidazolidine-2,4-dione (epoxy equivalent of 135-143 g / eq), glycidyl ether oxygen propyl cyclotetrasiloxane (epoxy equivalent of 160-190 g / eq) and the like are preferably used as component resins to jointly constitute the resin matrix.

[0009] Optionally, the composite curing agent is composed of a main curing agent component and a latent polyphosphazene curing agent, the main curing agent component is a compound of one or more high-temperature resistant aromatic amines, alicyclic amines, etc. The aromatic amine curing agents include: diethyltoluenediamine, dimethylthiotoluenediamine, metaphenylenediamine, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenylmethane, etc., and the alicyclic amine curing agents include: 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, isophoronediamine, etc. Preferably, 4,4'-diaminodiphenylmethane, diethyltoluenediamine, dimethylthiotoluenediamine, and 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane are selected as the main curing agent components and mixed with a latent polyphosphazene curing agent to obtain a composite curing agent with excellent high temperature resistance. The high temperature resistance is further improved by increasing the content of the heat-resistant macrocyclic structure of the system. At the same time, the selected curing agents such as dimethylthiotoluenediamine themselves have good latency and excellent rheological properties, which can further optimize the dry processability of the resin system and improve the processing convenience and storage stability of the resin system for the preparation of prepreg tapes.

[0010] Optionally, the latent polyphosphazene curing agent is an organic / inorganic hybrid polymer having a phosphazene ring and an aromatic ring structure, the synthetic raw materials are selected from A2 monomer and B6 monomer, and a terminal amine curing agent with a hyperbranched structure and a size of 200-800nm ​​is prepared by solution polymerization. On this basis, alicyclic or aromatic diisocyanate is used to cap the latent property at room temperature to achieve regulation. A2 monomers include: 4,4'-diaminodiphenyl sulfone, 4,4'-diaminobenzophenone, 3,3'-diamino-4,4'-dihydroxydiphenyl sulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, etc.; B6 monomers include: hexafluorocyclotriphosphazene, hexachlorocyclotriphosphazene, hexa(p-carboxyphenoxy)cyclotriphosphazene, hexa(4-carboxyphenoxy)cyclotriphosphazene, hexa(allyloxy)cyclotriphosphazene, etc.; alicyclic or aromatic diisocyanate capping agents include: toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, etc. Preferably, hexachlorocyclotriphosphazene and 4,4'-diaminodiphenyl sulfone are used as reaction monomers, triethanolamine is used as an acid-binding agent, and acetonitrile is used as a solvent for solution polymerization to prepare a hyperbranched polyphosphazene curing agent; the terminal amine polyphosphazene is mixed with isophorone diamine diisocyanate, and the active amine group of the curing agent is blocked at room temperature so that it can only be unblocked again after it rises to a specific temperature, thereby giving the polyphosphazene curing agent good latency. The hyperbranched structure increases the toughness by increasing the free volume of the material, and at the same time, it has abundant terminal groups that can chemically bond with the resin matrix to strengthen the mechanical properties of the material. In addition, the introduction of phosphazene rings and benzene rings helps to improve the high temperature resistance of the system, and achieves the simultaneous enhancement of the high temperature resistance and mechanics of the resin matrix by the high temperature resistant component.

[0011] Optionally, the high temperature resistant modified component is an amino-terminated metal phthalocyanine, which is an amino-terminated cobalt phthalocyanine, copper phthalocyanine, iron phthalocyanine or zinc phthalocyanine with a planar macrocyclic structure. Nitrophthaloyl derivatives, urea, metal chlorides and catalysts are selected as reaction raw materials, and a terminal nitrophthalocyanine intermediate is obtained by microwave heating, and then a reducing agent is used to convert the nitro group into an amino group to obtain a metal phthalocyanine with an amino-terminated structure. The selection of raw material monomers should meet the synthesis requirements of the phthalocyanine structure. Nitroamide, diacid or anhydride can form a planar macrocyclic conjugated structure composed of four isoindole units with urea under certain conditions. Nitrophthaloyl derivatives include: 4-nitrophthalamide, 4-nitrophthalic acid, 4-nitrophthalonitrile, etc.; metal chlorides include: cobalt chloride hexahydrate, cupric chloride dihydrate, ferrous chloride tetrahydrate, zinc acetate dihydrate, etc.; catalysts include: ammonium molybdate, 1,8-diazacyclo[5,4,0]undecene-7, sodium-molybdenum composite catalysts, etc. Preferably, 4-nitrophthalamide, urea and copper chloride dihydrate are mixed, ammonium molybdate is used as a catalyst, and the mixture is evenly mixed and then microwaved to prepare copper tetranitrophthalocyanine. The product is washed and then heated with sodium sulfide nonahydrate in DMF for reaction, and then washed and dried to obtain copper tetraaminophthalocyanine. The macrocyclic structure of phthalocyanine can further enhance the high temperature resistance of the resin system, and the polyamino reaction sites can further regulate and improve the rigid structure of the cross-linked network by participating in the formation process of the epoxy cross-linked network, thereby improving the high temperature resistance of the resin system, and the terminal amino group improves the compatibility of the epoxy resin system, and also has an auxiliary regulating effect on the curing activity and rheological properties of the resin system.

[0012] Preferably, the composite curing agent is a mixture of aromatic amine, alicyclic amine and latent polyphosphazene, wherein the aromatic amine is 100 parts, the alicyclic amine is 5-20 parts and the polyphosphazene is 10-30 parts.

[0013] The method for preparing a high temperature resistant resin system for dry winding prepreg is characterized by the following preparation steps:

[0014] 1) Preparation process of resin matrix: The resin matrix is ​​mixed with a main resin and a plurality of component resins, wherein the main resin is 60-100 parts and the component resin is 10-50 parts, heated to 80-150° C. and mixed with a mechanical stirrer at a speed of 300-600 rpm for 5-15 minutes until the system is uniform and transparent, to obtain a resin matrix with suitable viscosity and tack;

[0015] 2) Preparation process of latent polyphosphazene curing agent: tetrahydrofuran, N,N'-dimethylformamide or acetonitrile are selected as solvent, A2 monomer and B6 monomer are reacted at 40-80°C for 4-8h in a mass ratio of 2.5-2.8:1-1.2, precipitated and separated, washed and dried, and then the product and diisocyanate blocking agent are heated to 60-80°C in dimethyl sulfoxide or N,N'-dimethylformamide for 0.5-3h to block, thereby obtaining latent polyphosphazene curing agent;

[0016] 3) Preparation process of composite curing agent: The main curing agent component is selected from high temperature resistant aromatic amine and alicyclic amine with room temperature viscosity lower than 1000mPa·s, and a latent polyphosphazene curing agent is added. The above three components are mixed and prepared in a mass ratio of 100:5-20:1-30, heated to 80-180°C and mechanically stirred for 10-30min, and a uniform and stable composite curing agent can be obtained;

[0017] 4) Preparation process of high temperature resistant modified component: select nitrophthaloyl derivatives, urea, metal chloride and catalyst as reaction raw materials, mix the raw materials evenly according to the stoichiometric ratio, react at 160-200°C for 1-3h, wash the obtained nitrophthalocyanine intermediate and add the reducing agent to react for 1-3h, wash and purify the product, and the terminal amino metal phthalocyanine high temperature resistant modified component can be obtained.

[0018] 5) Preparation process of high temperature resistant resin system: the resin matrix prepared in step 1), the composite curing agent prepared in step 3) and the high temperature resistant modified component prepared in step 4) are mixed at a mass ratio of 100:10-50:1-15 at 60-120°C with stirring for 10-15 minutes to obtain a resin system for dry winding with excellent high temperature resistance.

[0019] The high temperature resistant resin system and preparation method for dry winding prepreg are characterized in that the prepared high temperature resistant resin system is subjected to a certain preparation process to prepare the dry winding prepreg, and the processability of the prepared resin system and the "smart adhesion" characteristics of the prepreg are evaluated by the following evaluation means, mainly as follows:

[0020] 1) Preparation of "smart adhesion" property test: The high temperature resistant resin system must be compatible with the prepreg preparation process. Under the condition of retaining a wide adjustable range of process parameters, the resin viscosity is low during high temperature infiltration to achieve good infiltration of the resin and fiber, and the resin viscosity is high during low temperature shaping to achieve the cluster shaping of the prepreg. This test adopts the rotation viscosity method in GB / T12007.4-89 for characterization. The viscosity should be higher than 90000mPa·s at 25°C and lower than 3000mPa·s at 80°C.

[0021] 2) Test of the “smart adhesion” property of yarn release: The prepreg tape made of the high temperature resistant resin system needs to be rolled up and stored in a certain linear shape. Therefore, it needs to be pulled under a certain tension during use to achieve continuous and stable yarn release without damaging the prepreg tape. This test adopts the parallel pulling test method. The specific operation is as follows: Apply a tension of 10-50N to make the yarn release direction tangent to the coil body, such as Figure 1 As shown in (a), the classification and evaluation are carried out based on the peeling state of the prepreg on the coil. The evaluation indicators are divided according to the bonding condition when the yarn is released, the amount of resin overflow on the surface of the prepreg, the amount of fuzzing and the edge regularity. Figure 1 As shown in (bd) in the figure, the evaluation is performed based on the bonding of the prepreg tape during yarn laying, the amount of surface resin overflow, the amount of fuzzing, and the edge regularity;

[0022] 3) Test of the "smart adhesion" property of winding: The prepreg made of the high temperature resistant resin system needs to meet the application requirements of dry winding molding, so it is necessary to use a variable angle and variable tension winding method to test the slippage of the prepreg during the winding process; this test uses a variable angle and variable tension winding test method, and spirally winds the prepreg on the surface of the core mold under a tension of 10-100N to observe whether the prepreg will slip during the variable angle winding of 15-90 degrees. The possible slippage of the prepreg is as follows: Figure 2 As shown, the evaluation was performed based on the slippage of the prepreg tape on the mandrel.

[0023] The high temperature resistant resin system and preparation method for dry winding prepreg tape, when evaluating the "smart adhesion" characteristics of the prepared resin system and prepreg tape, comprehensively consider various indicators in the "smart adhesion" characteristic test, and divide the "smart adhesion" characteristics of the prepreg tape into five levels. The evaluation criteria are as follows:

[0024] Table 1 Evaluation criteria for the “smart adhesion” level of prepreg tapes

[0025] Prepreg tape grades Yarn bonding condition Surface resin overflow The amount of hair adhesion between layers Edge regularity Excellent No bonding Very rare none Completely regular good Slightly bonded Very rare less Basic regularity generally Slightly bonded Partial overflow less Partially incomplete Poor Severe adhesion More overflow More Partially incomplete Very bad Severe adhesion More overflow a lot of Often damaged

[0026] Effects of the Invention

[0027] (1) By selecting dicyclopentadiene-type phenolic epoxy and multifunctional naphthalene epoxy resins as the main resins, a variety of component resins with excellent high temperature resistance and mechanical properties are selected to participate in the rheological properties and high temperature resistance of the resin matrix, ensuring that the physical properties of the resin matrix are dynamically matched with the requirements of the dry process while improving the high temperature resistance of the resin system;

[0028] (2) Introducing inorganic phosphazene ring structures into the design of organic molecular structures, designing and preparing organic / inorganic hybrid latent polyphosphazene curing agents, mixing them with high-temperature resistant low-viscosity aromatic amines and alicyclic amines as secondary curing agents, and then introducing metal phthalocyanine high-temperature modified components to participate in the formation of epoxy cross-linking networks, thereby synergistically regulating the high-temperature resistance and mechanical properties of the resin system;

[0029] (3) Based on the actual process requirements for the preparation and application of prepreg tapes, and taking into account the coordinated matching of "materials-processes", an evaluation method for the "smart adhesion" properties of prepreg tapes for dry winding was established around the key indicators of the "smart adhesion" property test, which has guiding significance for the development and iteration of resin systems for prepreg tapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of evaluation method and index classification of prepreg tape

[0031] Figure 2 Schematic diagram of possible yarn slippage during dry winding of prepreg tape

[0032] Figure 3 Schematic diagram of viscosity-temperature law of resin system for dry and wet winding DETAILED DESCRIPTION

[0033] The present invention provides a high temperature resistant resin system for dry winding prepreg tape and a preparation method. The present invention is further explained below through examples and comparative examples, but the present invention is not limited to the following examples; the present invention can be explained in other broader aspects and is not limited by these examples.

[0034] High temperature resistance performance example 1

[0035] Hexachlorocyclotriphosphazene and 4,4'-diaminodiphenyl sulfone, triethanolamine as acid binding agent, acetonitrile as solvent for solution polymerization, react for 6 hours under N2 atmosphere, take the product and wash it, add isophorone diisocyanate to react for 2 hours to obtain a latent polyphosphazene curing agent; diethyltoluenediamine, 4,4'-diaminodicyclohexylmethane and polyphosphazene are mixed in an optimal ratio of 40:7.5:6 and added into a beaker with mechanical stirring, heated to 80°C, stirring speed of 600r / min, time for 45min, to obtain a composite curing agent; 4-nitrophthalamide, urea and cupric chloride dihydrate are mixed, ammonium molybdate is used as a catalyst, mixed evenly and heated in a microwave for 1.5 hours, the product is washed, heated and stirred with sodium sulfide nonahydrate in DMF for 2.5 hours, washed The tetraaminophthalocyanine copper high temperature modified component is obtained by drying; then poly[(phenyl glycidyl ether)-co-dicyclopentadiene], 1,5-naphthalene diamine tetraepoxy, 4,4'-diaminodiphenylmethane tetraglycidylamine and glycidyl ether oxypropyl cyclotetrasiloxane are compounded according to a mass fraction of 60:20:30:10, and then mixed with a composite curing agent according to the ratio of epoxy group: active hydrogen of amine = 1:1, and finally 5 parts of the high temperature modified component are added, and the mixing conditions are oil bath 125°C, stirring speed 400r / min, time 10min, vacuum degassing for 15min, and then poured into a metal mold for curing treatment, and the curing system is 90°C / 1h+120°C / 2h+150°C / 3h. After natural cooling and demolding, it is polished and tested according to national standards.

[0036] The specific formula design of each component in this embodiment is shown in Table 2, and the test results of the mechanical properties of the casting body and other process characteristics of the resin system are shown in Tables 3 and 4. From the test data in Tables 3 and 4, it can be seen that the resin system in this embodiment has good high temperature resistance and mechanical properties, and the process characteristics are suitable for dry winding molding process.

[0037] High temperature resistance performance comparison example 1-1

[0038] The polyphosphazene curing agent and the high temperature resistant modified component are not added, and the ratios of the other components and the experimental steps are the same as those in Example 1. By comparison, it can be seen that the polyphosphazene curing agent and the high temperature resistant modified component significantly improve the high temperature resistance of the resin system without substantially losing mechanical properties, that is, the resin system of Example 1 has better comprehensive performance.

[0039] High temperature resistance performance comparison example 1-2

[0040] The preparation method of the polyphosphazene curing agent and the high temperature resistant modified component is the same as that in Example 1; diethyltoluenediamine, 4,4'-diaminodicyclohexylmethane and polyphosphazene are mixed in a mass ratio of 40:7.5:9, and the remaining experimental steps are the same as those in Example 1. By comparison, it can be seen that the increase in the content of the polyphosphazene component significantly improves the high temperature resistance of the system, but the agglomeration caused by excessive addition is prone to loss of mechanical properties.

[0041] High temperature resistance performance example 2

[0042] The preparation method of the polyphosphazene curing agent and the high temperature resistant modified component is the same as that in Example 1; diethyltoluenediamine, 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane and polyphosphazene are mixed in an optimal ratio of 40:5:2.5:6 and added into a beaker with mechanical stirring, and the heating temperature is 80°C, the stirring speed is 600r / min, and the time is 45min to obtain a composite curing agent; poly[(phenyl glycidyl ether)-co-dicyclopentadiene], 1,5-naphthalene diamine tetraepoxy, 5,5'-dimethyl-1,3-di(ethylene oxide) Methyl) imidazolidine-2,4-dione and glycidyl ether oxypropyl cyclotetrasiloxane are compounded in a mass fraction of 60:20:30:10, and then mixed with a composite curing agent in the ratio of epoxy group: active hydrogen of amine = 1:1, and finally 5 parts of high temperature resistant modified components are added. The mixing conditions are oil bath 125°C, stirring speed 400r / min, time 10min, vacuum degassing for 15min, and then poured into a metal mold for curing treatment. The curing system is 90°C / 1h+120°C / 2h+150°C / 3h. After natural cooling and demoulding, it is polished and tested according to national standards.

[0043] The specific formula design of each component in this embodiment is shown in Table 2, and the test results of the mechanical properties of the casting body and other process characteristics of the resin system are shown in Tables 3 and 4. From the test data in Tables 3 and 4, it can be seen that the resin system in this embodiment has good high temperature resistance and mechanical properties, and the process characteristics are suitable for dry winding molding process.

[0044] High temperature resistance performance comparison example 2-1

[0045] No polyphosphazene curing agent and high temperature resistant modified component were added, and the ratio of other components and the experimental steps were the same as those in Example 2. By comparison, it can be seen that the addition of polyphosphazene in Example 2 helps to improve the high temperature resistance of the resin system, and compared with Example 1, it can be seen that hydantoin epoxy is beneficial to the enhancement of the tensile properties and rheological processability of the material system.

[0046] High temperature resistance performance comparison example 2-2

[0047] The preparation method of the polyphosphazene curing agent and the high temperature resistant modified component is the same as that in Example 1; diethyltoluenediamine, 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane and polyphosphazene are mixed in a mass ratio of 40:5:2.5:9, and the remaining experimental steps are the same as those in Example 2. By comparison, it can be seen that as the content of the polyphosphazene component increases, the high temperature resistance of the system is significantly improved, and the mechanical properties are slightly lost.

[0048] High temperature resistance performance example 3

[0049] The preparation method of the polyphosphazene curing agent and the high temperature resistant modified component is the same as that in Example 1; dimethylthiotoluene diamine, 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane and polyphosphazene are mixed in an optimal ratio of 40:2.5:5:6 and added into a beaker with mechanical stirring, and the heating temperature is 80°C, the stirring speed is 600r / min, and the time is 45min to obtain a composite curing agent; poly[(phenyl glycidyl ether)-co-dicyclopentadiene], 1,5-naphthalene diamine tetraepoxy, 4,4'-diaminodiphenylmethane tetraglycidylamine and 5,5 '-Dimethyl-1,3-di(oxiranylmethyl)imidazolidine-2,4-dione was compounded in a mass fraction of 60:20:15:25, and then mixed with a composite curing agent in the ratio of epoxy group:active hydrogen of amine=1:1, and finally 5 parts of high temperature resistant modified components were added. The mixing conditions were oil bath 125°C, stirring speed 400r / min, time 10min, and vacuum degassing for 15min before pouring it into a metal mold for curing treatment. The curing system was 90°C / 1h+120°C / 2h+150°C / 3h. After natural cooling and demoulding, it was polished and tested according to national standards.

[0050] The specific formula design of each component in this embodiment is shown in Table 2, and the test results of the mechanical properties of the casting body and other process characteristics of the resin system are shown in Tables 3 and 4. From the test data in Tables 3 and 4, it can be seen that the resin system in this embodiment has good high temperature resistance and mechanical properties, and the process characteristics are suitable for dry winding molding process.

[0051] High temperature resistance performance comparison example 3-1

[0052] No polyphosphazene curing agent and high temperature resistant modified component were added, and the ratio of other components and the experimental steps were the same as those in Example 3. By comparison, it can be seen that the addition of polyphosphazene in Example 3 can also further improve the high temperature resistance of the resin system. Compared with Example 1, it can be seen that the silicone epoxy has a significant effect on the rheological processability, and the methylthio-substituted aromatic amine curing agent system has a longer process window.

[0053] High temperature resistance performance comparison example 3-2

[0054] The preparation method of the polyphosphazene curing agent and the high temperature resistant modified component is the same as that in Example 1; dimethylthiotoluenediamine, 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane and polyphosphazene are mixed in a mass ratio of 40:2.5:5:9, and the remaining experimental steps are the same as those in Example 3. By comparison, it can be seen that with the increase of the content of the polyphosphazene component, the high temperature resistance of the system is significantly improved, and the mechanical properties of the system are seriously lost due to the lack of regulation of silicone epoxy.

[0055] Example of "Smart Adhesion" Characteristics of Prepreg Tape Preparation Process

[0056] The preparation and mixing methods of the components of the resin system are the same as those in Example 1; the test is carried out using a rotational viscometer according to standard GB / T12007.4-89, and the results are as follows: Figure 3 As shown in (1), the viscosity of the resin system for dry winding should be higher than 90000 mPa·s at 25°C and lower than 3000 mPa·s at 80°C.

[0057] Comparative example of "smart bonding" characteristics of prepreg tape preparation process

[0058] The common wet winding resin system is configured as follows: bisphenol A diglycidyl ether (CYD128) and diethyltoluenediamine are mixed evenly at a mass ratio of 100:24; a rotational viscometer is used to test according to standard GB / T 12007.4-89. The results are as follows Figure 3 As shown in (2), the viscosity of the wet winding resin at both low and high temperatures is much lower than that of the dry winding resin.

[0059] Example of "smart bonding" characteristics of prepreg tape laying process

[0060] The prepreg coil prepared by the resin system of Example 1 was selected, and the process parameters were adjusted to control the resin volume fraction of the prepreg to be 28±2%. Figure 1 The parallel pulling test shown in the figure shows the yarn laying results. Figure 1 As shown in case (1), there is no glue overflow on the surface of the prepreg tape, the edge regularity is high, and there is no fuzzing when the yarn is laid. It is rated as "excellent" according to the method in Table 1.

[0061] Comparative Example 1 of the “Smart Bonding” Characteristics of Prepreg Tape Yarn Laying Process

[0062] The prepreg coil prepared by the resin system of Example 1 was selected, and the process parameter adjustment accuracy was reduced so that the resin volume fraction of the prepreg was 35±5%. Figure 1 The parallel pulling test shown in the figure shows the yarn laying results. Figure 1As shown in case (2), there is a small amount of glue overflow on the surface of the prepreg tape, the edge regularity is average, and there is a small amount of fuzzing when the yarn is laid. It is rated as "average" according to the method in Table 1.

[0063] Comparative Example 2 of “Smart Bonding” Characteristics of Prepreg Tape Yarn Laying Process

[0064] The resin system of Example 1 is selected without adding glycidyloxypropyl cyclotetrasiloxane, and the process parameters are adjusted to reduce the precision so that the resin volume fraction of the prepreg is 35±5%. Figure 1 The parallel pulling method shown in the figure is used to test the obtained prepreg tape, and the yarn laying results are shown in FIG. Figure 1 As shown in case (3), the prepreg tape surface has a lot of glue overflow and is uneven, the edge is very poorly regular and often has adhesion damage, and the yarn is severely fuzzed when it is laid. It is rated as "very poor" according to the method in Table 1.

[0065] Example of “Smart Adhesion” Characteristics of Prepreg Tape Winding Process

[0066] The prepreg coil prepared by the resin system of Example 1 was selected to carry out a variable angle and variable tension winding test. The spiral winding was carried out at a fixed winding angle each time, and the tension was gradually increased from 10N to 100N. The prepreg did not slip during the spiral winding of 15-90 degrees.

[0067] Comparison of “smart bonding” characteristics of prepreg winding process

[0068] The wet winding resin system used in the comparative example of the "smart adhesion" property of the prepreg preparation process was selected to carry out the variable angle and variable tension winding test. The spiral winding was carried out at a fixed winding angle each time, and the tension was gradually increased from 10N to 100N. It can be seen that when the winding angle of wet winding is less than 45 degrees, once the tension exceeds 50N, the yarn will slip. The direction of the slip trend is as follows Figure 2 shown.

[0069] Table 2 Mass fraction of each component in the embodiments and comparative examples

[0070]

[0071] Table 3 Test results of resin glue performance of the embodiments and comparative examples

[0072]

[0073] Table 4 Mechanical properties test results of resin casting bodies of embodiments and comparative examples

[0074]

Claims

1. A high temperature resistant resin system for dry winding prepreg tape, characterized in that: The resin system is composed of a resin matrix, a composite curing agent and a high temperature resistant modified component, and is characterized in that the resin system has the following proportions: 100 parts of the resin matrix, 10-50 parts of the composite curing agent, and 1-15 parts of the high temperature resistant modified component.

2. A high temperature resistant resin system for dry winding prepreg according to claim 1, characterized in that: The resin matrix is ​​formed by mixing a main resin and a component resin in a mass ratio of 60-100:10-50. The main resin is a compound of one or more of dicyclopentadiene phenolic epoxy resin and multifunctional naphthalene epoxy resin, and the component resin is a compound of one or more of glycidylamine type, hydantoin type and silicone modified epoxy resin.

3. A high temperature resistant resin system for dry winding prepreg according to claim 1, characterized in that: The latent polyphosphazene curing agent is an organic / inorganic hybrid polymer having a phosphazene ring and an aromatic ring structure. An aromatic diamine monomer (hereinafter referred to as A2 monomer) and a hexafunctional monomer having a phosphazene ring structure (hereinafter referred to as B6 monomer) are selected. The reactive group of the B6 monomer is polymerized with the amine group of the A2 monomer to prepare an amine-terminated curing agent having a hyperbranched structure and a size of 200-800 nm. An alicyclic or aromatic diisocyanate is used as a capping agent to obtain a polyphosphazene curing agent having room temperature latency.

4. A high temperature resistant resin system for dry winding prepreg according to claim 1, characterized in that: The high temperature resistant modified component is one of cobalt phthalocyanine, copper phthalocyanine, iron phthalocyanine or zinc phthalocyanine with a polyamino structure. Nitrophthaloyl derivatives, urea, metal chloride and catalyst are selected as reaction raw materials. A terminal nitrophthalocyanine intermediate is obtained by microwave heating, and then a reducing agent is used to convert the nitro group into an amino group to obtain a terminal amino metal phthalocyanine high temperature resistant modified component.

5. A high temperature resistant resin system for dry winding prepreg according to claim 1, characterized in that: The composite curing agent is composed of a main curing agent component and a latent polyphosphazene curing agent, wherein the main curing agent component is a compound of one or more of high temperature resistant aromatic amines and alicyclic amines, and the main curing agent component and the latent polyphosphazene curing agent component are uniformly mixed in a mass ratio of 100-120:1-30 by mechanical stirring to obtain the composite curing agent.

6. A method for preparing a high temperature resistant resin system for dry winding prepreg tape, used for preparing a high temperature resistant resin system for dry winding prepreg tape as described in any one of claims 1 to 6, characterized in that: The preparation process is as follows: (1) Preparation process of resin matrix: The resin matrix is ​​mixed with a main resin and a component resin, wherein 60-100 parts of the main resin and 10-50 parts of the component resin are heated to 80-150° C. and mixed with a mechanical stirrer at a speed of 300-600 rpm for 5-15 minutes until the system is uniform and transparent, thereby obtaining a resin matrix with suitable viscosity and tack; (2) Preparation process of latent polyphosphazene curing agent: tetrahydrofuran, N,N'-dimethylformamide or acetonitrile are selected as solvent, A2 monomer and B6 monomer are reacted at a mass ratio of 2.5-2.8:1-1.2 at 40-80°C for 4-8h, precipitated and separated, washed and dried, and then the product and diisocyanate blocking agent are heated to 60-80°C in dimethyl sulfoxide or N,N'-dimethylformamide for 0.5-3h to block, thereby obtaining latent polyphosphazene curing agent; (3) Preparation process of composite curing agent: The main curing agent component is selected from high temperature resistant aromatic amine and alicyclic amine with room temperature viscosity lower than 1000 mPa·s, and the main curing agent component and latent polyphosphazene curing agent are mixed in a mass ratio of 100-120:1-30, and heated to 80-180° C. and mechanically stirred for 10-30 minutes to obtain a uniform and stable composite curing agent; (4) Preparation process of high temperature resistant modified component: select nitrophthaloyl derivative, urea, metal chloride and catalyst as reaction raw materials, mix the raw materials evenly, react at 160-200°C for 1-3h, wash the obtained nitrophthalocyanine intermediate and add reducing agent to react for 1-3h, wash and purify the product, and obtain terminal amino metal phthalocyanine high temperature resistant modified component. (5) Preparation process of high temperature resistant resin system: The resin matrix prepared in step (1), the composite curing agent prepared in step (3) and the high temperature resistant modified component prepared in step (4) are mixed at a mass ratio of 100:10-50:1-15 at 60-120° C. and stirred for 10-15 min to obtain a resin system for dry winding with excellent high temperature resistance.

7. A dry winding prepreg tape, prepared from the resin system obtained by the method of claim 6, characterized in that: The processability of the prepared resin system and the "smart adhesion" characteristics of the prepreg tape were evaluated by the following evaluation methods, as follows: (1) Preparation of "smart adhesion" property test: The resin system used to prepare the prepreg tape was tested at 25°C and 80°C according to the rotational viscosity method in GB / T 12007.4-89, and evaluated based on the viscosity; (2) Yarn laying "smart adhesion" property test: simulate the actual use scenario of prepreg coils, and test the prepared prepreg by parallel traction yarn laying under a certain tension. The prepreg adhesion, surface resin overflow, fuzzing and edge regularity are evaluated during yarn laying. (3) Winding "smart adhesion" property test: Simulate the actual dry winding scenario, use the prepared prepreg tape to carry out 15-90 degree variable angle winding under a certain tension, and evaluate based on the slippage of the prepreg tape on the core mold.

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