Carbon fiber unmanned aerial vehicle part forming process

Abstract

The invention discloses a carbon fiber unmanned aerial vehicle part forming technology, and belongs to the technical field of unmanned aerial vehicle forming, and the technology comprises the following steps: taking a polymer latex air bag which is matched with the shape of an unmanned aerial vehicle part and retracts after being heated as a mold core; carbon fiber prepreg is laid on the surface of the mold core through a multi-angle and multi-layer laying technology, and a preformed part is obtained; the paving process comprises the following steps: sequentially paving a first carbon cloth layer, a second carbon cloth layer, a third carbon cloth layer, a fourth carbon cloth layer, a fifth carbon cloth layer and a sixth carbon cloth layer from inside to outside; molding the preformed part on a hot press, and removing the mold core to obtain a carbon fiber unmanned aerial vehicle part crude product; and the carbon fiber unmanned aerial vehicle part crude product is polished and refined, and a carbon fiber unmanned aerial vehicle part finished product is obtained. According to the invention, the paving between multiple layers of carbon cloth is smooth and stable.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of unmanned aerial vehicle part forming processing, and relates to a carbon fiber unmanned aerial vehicle part forming process. BACKGROUND

[0002] Carbon fiber is a new type of fiber material with a carbon content of more than 95%, high strength, high modulus and high temperature resistance, and is the first among all chemical fibers in terms of high temperature resistance. It is widely used in the fields of aerospace, electric power, new energy and major infrastructure projects. The wide application of carbon fiber not only brings "lightweight" in the application field, but also brings additional effects of "energy saving and emission reduction".

[0003] Carbon fiber can significantly improve the flight performance, load capacity and environmental adaptability of unmanned aerial vehicles due to its excellent performance, and is often used to prepare landing gear and arms and other parts of unmanned aerial vehicles. In the manufacturing process of unmanned aerial vehicles, the application of carbon fiber is usually combined with integrated forming technology. Integrated forming technology is a technology in which multiple layers of carbon fiber cloth are covered on a preform model, and then through curing, forming and heat treatment and other steps, the carbon fiber cloth is tightly combined with the model to finally form the frame structure of the unmanned aerial vehicle. However, due to the integration of multiple layers of carbon cloth, internal stress concentration or mutual constraint during the curing and shrinkage of each layer of resin is easily caused in the integrated forming process, resulting in uneven shrinkage, deformation, cracks, bubbles, uneven surface, poor finish and other common defects, and a high rate of defective products in the production process. SUMMARY

[0004] The purpose of the present application is to provide a carbon fiber unmanned aerial vehicle part forming process that solves the above problems.

[0005] The technical scheme adopted by the present application is as follows: A carbon fiber unmanned aerial vehicle part forming process, comprising the following steps: S1, using a heated and shrunk high molecular latex air bag matching the shape of the unmanned aerial vehicle part as a mold core; S2, laying carbon fiber prepreg on the surface of the mold core through a multi-angle and multi-layer laying process to obtain a preform; the multi-angle and multi-layer laying process comprises the following steps: laying a first carbon cloth layer, a second carbon cloth layer, a third carbon cloth layer, a fourth carbon cloth layer, a fifth carbon cloth layer and a sixth carbon cloth layer from inside to outside; The first carbon cloth layer and the sixth carbon cloth layer are both composed of 3K twill-200 carbon fiber prepreg; The second carbon cloth layer and the fifth carbon cloth layer are both composed of ±C45°-150 carbon fiber prepreg; The third carbon cloth layer is composed of C0°-150 carbon fiber prepreg; The fourth carbon cloth layer is composed of C90°-150 carbon fiber prepreg; S3, hot pressing on the preform, after removing the mold core, obtaining the carbon fiber unmanned aerial vehicle part roughcast; S4, polishing and finishing the carbon fiber unmanned aerial vehicle part roughcast, obtaining the carbon fiber unmanned aerial vehicle part finished product.

[0006] The application uses a high-molecular latex air bag that shrinks under heat as a mold core. During the heating forming and curing process, the mold core will shrink, reducing the volume, and separating from the formed product. When demolding, the mold core can be directly pulled out, which is simple and will not cause deformation or wear of the product appearance during demolding. In the application, the angles between the adjacent carbon cloth in the first carbon cloth layer, the second carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, the fifth carbon cloth layer, and the sixth carbon cloth layer are continuously transitioned, realizing the smooth and stable laying of the multiple layers of carbon cloth, and there are no significant gaps between adjacent layers.

[0007] Further, the fiber direction in the ±C45°-150 carbon fiber prepreg is arranged in two directions of 45° and -45°.

[0008] Further, the unmanned aerial vehicle part is a boom or a landing gear.

[0009] Further, the 3K twill-200 carbon fiber prepreg, the ±C45°-150 carbon fiber prepreg, the C0°-150 carbon fiber prepreg, and the C90°-150 carbon fiber prepreg are obtained by impregnation treatment with the same resin composition.

[0010] Further, the resin composition is composed of a resin slurry and a curing agent; the resin slurry is prepared from the following components in parts by weight: 5.5-7.5 parts of a spiroorthocarbonate monomer modified MOF derived ZnO@C composite, 30-35 parts of a bisphenol A epoxy resin, 35-40 parts of a bisphenol F epoxy resin, 8-10 parts of an epoxy diluent, 1-2 parts of a polyether modified polydimethylsiloxane dispersant, and an initiator; wherein the amount of the curing agent is 50% of the total amount of the bisphenol A epoxy resin and the bisphenol F epoxy resin; and the amount of the initiator is 0.8% of the mass of the spiroorthocarbonate monomer modified MOF derived ZnO@C composite.

[0011] In order to adapt to the multi-layer and multi-angle carbon cloth, avoid the uneven shrinkage stress between the multi-layer carbon cloth due to the thermal shrinkage of the epoxy resin in the heating and curing process, and the deformation phenomenon such as delamination and warping occurs; the spiro orthocarbonate expansion monomer is introduced into the resin to offset the thermal shrinkage of the epoxy resin; in the introduction process of the spiro orthocarbonate expansion monomer, the MOF derived ZnO@C composite is used as the carrier of the spiro orthocarbonate expansion monomer, and the porous structure thereof is utilized to inhibit the expansion rate of the expansion monomer to a certain extent and maintain the entire resin system in a relatively balanced state; because, the obvious shrinkage or expansion of the entire resin composition during curing will affect the uneven change of the interlayer flow, and in the actual application process, although the epoxy resin will shrink due to heating, the shrinkage rate of the epoxy resin is not high, and in general cases, it is lower than the expansion rate of the spiro orthocarbonate expansion monomer, therefore, the application wants to use the MOF derived ZnO@C composite as the carrier of the spiro orthocarbonate expansion monomer to inhibit the expansion degree of the expansion monomer, avoid the phenomenon that the resin composition will obviously expand during the curing process, and help to maintain the balance of the shrinkage and expansion of the entire resin system. In addition, the MOF derived ZnO@C composite has stable performance and certain thermal conductivity, which can not only enhance the mechanical properties of the resin, but also help to uniformly transfer heat during curing and reduce the stress caused by temperature gradient.

[0012] Further, the spiro orthocarbonate expansion monomer modified MOF derived ZnO@C composite is prepared by the following method: The MOF-74(Zn) precursor is placed in a tube furnace, calcined under argon protection, and cooled to obtain the MOF derived ZnO@C composite; the MOF derived ZnO@C composite is dispersed in toluene, stirred uniformly, and then 3-aminopropyltriethoxysilane and glacial acetic acid are added and heated to react, filtered to obtain the aminated MOF derived ZnO@C composite; The spiro orthocarbonate expansion monomer and 3-glycidyl ether propyltrimethoxysilane are heated to react under the catalysis of dibutyltin dilaurate to obtain an intermediate; the aminated ZnO@C composite is dispersed in anhydrous toluene, and the intermediate and triethylamine are added and heated to react, filtered, washed and dried to obtain the spiro orthocarbonate expansion monomer modified MOF derived ZnO@C composite; wherein the spiro orthocarbonate expansion monomer is 3,9-dihydroxymethyl-3',9'-diethyl-1,5,7,11-tetraoxaspiro[5,5]undecane.

[0013] Further, the epoxy diluent is allyl glycidyl ether AGE.

[0014] Further, the curing agent is methyl hexahydrophthalic anhydride, and the initiator is triflic anhydride initiator.

[0015] Further, the resin composition is prepared by the following method: mixing bisphenol A epoxy resin, bisphenol F epoxy resin and epoxy diluent, mechanically stirring at room temperature for 15-20 minutes to obtain a uniform resin base liquid; adding polyether modified polydimethylsiloxane dispersant and spiro orthocarbonate expansion monomer modified MOF derived ZnO@C composite into the resin base liquid, transferring to a high-speed dispersion machine, and high-speed shearing dispersion at room temperature for 30-45 minutes to obtain a premix slurry; adding initiator triflic anhydride into the premix slurry, and continuing to stir at room temperature for 10-15 minutes to obtain a resin slurry; before use, preheating the resin slurry to 45-50 DEG C, then adding a curing agent, stirring and defoaming to obtain the resin composition.

[0016] Further, the preform is shaped by a hot press in step S3, and the temperature is 145-150 DEG C; after removing the mold core, a carbon fiber unmanned aerial vehicle part crude product is obtained.

[0017] In summary, due to the adoption of the above technical solutions, the present application has the following advantages: 1. In the present application, the angles between adjacent carbon cloths in the first carbon cloth layer, the second carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, the fifth carbon cloth layer and the sixth carbon cloth layer are continuously transitioned, realizing the smooth and stable laying of the multi-layer carbon cloths, and there are no significant pores between adjacent layers, and the product after forming has no appearance defects and achieves the characteristics of light weight and high strength. 2. In the present application, the high polymer latex air bag which shrinks under heat is used as the mold core, and during the heating and forming and curing process, the mold core will shrink and the volume will decrease, and the mold core is separated from the formed product, and the mold core can be directly pulled out during demolding, so that the demolding is simple and the product appearance will not be deformed or abraded during demolding. 3. In the present application, in order to adapt to the multi-layer and multi-angle carbon cloth, avoid the uneven shrinkage stress between the multi-layer carbon cloths due to the thermal shrinkage of the epoxy resin during the heating and curing process, and avoid the deformation phenomena such as delamination and warping, the spiro orthocarbonate expansion monomer is introduced into the resin to offset the thermal shrinkage of the epoxy resin. 4. In the present application, the MOF derived ZnO@C composite is used as the carrier of the spiro orthocarbonate expansion monomer, which plays a role in uniform heating and mechanical property enhancement of the resin on the basis of maintaining the shrinkage and expansion balance of the entire resin system. DETAILED DESCRIPTION

[0018] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application, that is, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown herein can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present application provided is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0020] It should be noted that the relational terms such as "first" and "second" and the like are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus including a series of elements includes not only those elements, but also other elements not explicitly listed, or further includes elements inherent in such a process, method, article or apparatus. Without more limitations, the element defined by the statement "including a" does not exclude the presence of additional identical elements in the process, method, article or apparatus including the element.

[0021] The features and performances of the present application will be further described in detail below with reference to the embodiments.

[0022] The present application is a carbon fiber unmanned aerial vehicle part forming process, comprising the following steps: S1, using a heated and retracted polymer latex air bag matched with the shape of the unmanned aerial vehicle part as a mold core; S2, laying carbon fiber prepreg on the surface of the mold core through a multi-angle and multi-layer laying process to obtain a preformed part; the multi-angle and multi-layer laying process comprises the following steps: laying a first carbon cloth layer, a second carbon cloth layer, a third carbon cloth layer, a fourth carbon cloth layer, a fifth carbon cloth layer and a sixth carbon cloth layer in sequence from inside to outside; The first carbon cloth layer and the sixth carbon cloth layer are both composed of 3K twill-200 carbon fiber prepreg; The second carbon cloth layer and the fifth carbon cloth layer are both composed of ±C45°-150 carbon fiber prepreg; the fiber direction in the ±C45°-150 carbon fiber prepreg is arranged in a 45° and -45° direction interweave; The third carbon cloth layer is composed of C0°-150 carbon fiber prepreg; The fourth carbon cloth layer is composed of C90°-150 carbon fiber prepreg; S3, hot pressing on the preform, after removing the mold core, a carbon fiber unmanned aerial vehicle part crude product is obtained; S4, polishing and finishing the carbon fiber unmanned aerial vehicle part crude product to obtain a carbon fiber unmanned aerial vehicle part finished product.

[0023] In the following examples, the unmanned aerial vehicle part is an arm or a landing gear.

[0024] In the following examples, the 3K twill-200 carbon fiber prepreg, ±C45°-150 carbon fiber prepreg, C0°-150 carbon fiber prepreg, and C90°-150 carbon fiber prepreg are prepared by impregnation with the same resin composition.

[0025] In the following examples, the resin composition is composed of a resin slurry and a curing agent; the resin slurry is prepared from the following components in parts by weight: 5.5-7.5 parts of a spiroorthocarbonate dilatone modified MOF derived ZnO@C composite, 30-35 parts of a bisphenol A epoxy resin, 35-40 parts of a bisphenol F epoxy resin, 8-10 parts of an epoxy diluent, 1-2 parts of a polyether modified polydimethylsiloxane dispersant, and an initiator; wherein the amount of the curing agent is 50% of the total amount of the bisphenol A epoxy resin and the bisphenol F epoxy resin; the amount of the initiator is 0.8% of the mass of the spiroorthocarbonate dilatone modified MOF derived ZnO@C composite.

[0026] In the following examples, the spiroorthocarbonate dilatone modified MOF derived ZnO@C composite is prepared by the following method: The MOF-74(Zn) precursor is placed in a tube furnace, and under argon protection, it is raised to 200℃ at a rate of 1℃ / min, and held for 1h; then it is raised to 350℃ at a rate of 0.5℃ / min, and held for 2h; finally it is raised to 450℃ at a rate of 2℃ / min, and held for 4h, and cooled to obtain the MOF derived ZnO@C composite; 1g of the MOF derived ZnO@C composite is dispersed in 50 mL of toluene, and after stirring evenly, 2ml of 3-aminopropyltriethoxysilane and 0.1 mL of glacial acetic acid are added, and refluxed at 110℃ for 8h, and filtered to obtain the aminated MOF derived ZnO@C composite; 1g spiroorthocarbonate dilatant monomer (3,9-dihydroxymethyl-3',9'-diethyl-1,5,7,11-tetraoxaspiro[5,5]undecane) was reacted with 1.2g 3-glycidyloxypropyltrimethoxysilane under the catalysis of 0.05g dibutyltin dilaurate at 80°C for 6h to obtain an intermediate reactant (without separation, directly for the next step); 1g amino MOF derived ZnO@C composite was dispersed in 30mL anhydrous toluene, the intermediate reactant and 0.1g triethylamine were added, and stirring reaction was carried out at 80°C for 12h, then filtration, washing and drying were carried out to obtain a spiroorthocarbonate dilatant monomer modified MOF derived ZnO@C composite; wherein the spiroorthocarbonate dilatant monomer is 3,9-dihydroxymethyl-3',9'-diethyl-1,5,7,11-tetraoxaspiro[5,5]undecane.

[0027] In the following examples, the epoxy diluent is allyl glycidyl ether AGE.

[0028] In the following examples, the curing agent is methylhexahydrophthalic anhydride, and the initiator is triflic anhydride initiator.

[0029] In the following examples, the resin composition is prepared by the following method: the bisphenol A epoxy resin (liquid), bisphenol F epoxy resin (liquid) and epoxy diluent are mixed, mechanical stirring is carried out at room temperature at a speed of 500-800 rpm for 15-20 minutes to obtain a uniform resin base liquid; the polyether modified polydimethylsiloxane dispersant and the spiroorthocarbonate dilatant monomer modified MOF derived ZnO@C composite are added to the resin base liquid, and high-speed shearing dispersion is carried out in a high-speed dispersion machine at room temperature at a speed of 3000-3500 rpm for 30-45 minutes until the composite is uniformly dispersed and no visible agglomerates are present in the system to obtain a premix slurry; the initiator triflic anhydride is added to the premix slurry, and stirring is continued at room temperature at a speed of 500-800 rpm for 10-15 minutes to obtain a resin slurry; before use, the resin slurry is preheated to 45-50°C (preferably 50°C in actual use), then the curing agent is added, and stirring and defoaming are carried out to obtain the resin composition, which is used for impregnation treatment in the process of preparing carbon fiber prepreg.

[0030] In the following examples, the preform is shaped by a hot press in step S3 at a temperature of 145-150°C (preferably 150°C in actual preparation), and after the mold core is removed, a carbon fiber unmanned aerial vehicle part crude product is obtained.

[0031] Example 1

[0032] The carbon fiber unmanned aerial vehicle part forming process provided by the preferred embodiment of the present application takes the arm as the processing object, and includes the following steps: S1, using a heated-retracting polymer latex air bag matching the shape of the unmanned aerial vehicle part as a mold core; S2, laying carbon fiber prepreg on the surface of the mold core through a multi-angle, multi-layer laying process to obtain a preform; the multi-angle, multi-layer laying process comprises the following steps: laying a first carbon cloth layer, a second carbon cloth layer, a third carbon cloth layer, a fourth carbon cloth layer, a fifth carbon cloth layer, and a sixth carbon cloth layer in sequence from inside to outside; (the number of sheets used for each layer is determined according to the surface area of the processed part, and the processed part is completely covered by a single layer, and the thickness parameters of the carbon cloth used in the embodiment are 200g / m 2 , the thickness is 0.25mm / single layer, 150g / m 2 , the thickness is 0.15mm / single layer, and 3K twill is used for T700); The first carbon cloth layer and the sixth carbon cloth layer are both composed of 3K twill-200 carbon fiber prepreg; "-200" is the grammage, and "-150" has the same meaning below; The second carbon cloth layer and the fifth carbon cloth layer are both composed of ±C45°-150 carbon fiber prepreg; the fiber direction in the ±C45°-150 carbon fiber prepreg is arranged in 45° and -45° directions; The third carbon cloth layer is composed of C0°-150 carbon fiber prepreg; The fourth carbon cloth layer is composed of C90°-150 carbon fiber prepreg; S3, hot pressing the preform, the temperature is 150℃, and after removing the mold core, a carbon fiber unmanned aerial vehicle part crude product is obtained; S4, polishing and finishing the carbon fiber unmanned aerial vehicle part crude product to obtain a carbon fiber unmanned aerial vehicle part finished product; The 3K twill-200 carbon fiber prepreg, ±C45°-150 carbon fiber prepreg, C0°-150 carbon fiber prepreg, and C90°-150 carbon fiber prepreg are obtained by impregnation with the same resin composition, and the resin composition for impregnation treatment is composed of a resin slurry and a curing agent (methyl hexahydrophthalic anhydride), and the resin slurry is prepared from the following components in parts by weight: 5.5 parts of MOF-derived ZnO@C composite modified by spiro ortho carbonate expansion monomer, 30 parts of bisphenol A epoxy resin, 35 parts of bisphenol F epoxy resin, 8 parts of epoxy diluent (allyl glycidyl ether AGE), 1 part of polyether-modified polydimethylsiloxane dispersant, initiator (triflic anhydride initiator); wherein the amount of the curing agent is 50% of the total mass of the bisphenol A epoxy resin and the bisphenol F epoxy resin; the amount of the initiator is 0.8% of the mass of the MOF-derived ZnO@C composite modified by spiro ortho carbonate expansion monomer; and the resin composition is prepared by the following method: mixing the bisphenol A epoxy resin, the bisphenol F epoxy resin, and the epoxy diluent, mechanically stirring at a speed of 800 rpm at room temperature for 15 minutes to obtain a uniform resin base liquid; adding the polyether-modified polydimethylsiloxane dispersant and the MOF-derived ZnO@C composite modified by spiro ortho carbonate expansion monomer to the resin base liquid, transferring to a high-speed dispersion machine, and high-speed shearing dispersion at a speed of 3500 rpm at room temperature for 30 minutes until the composite is uniformly dispersed and the system has no visible agglomerates to obtain a premix slurry; adding the initiator triflic anhydride to the premix slurry, and continuing to stir at a speed of 500 rpm at room temperature for 15 minutes to obtain a resin slurry; before use, preheating the resin slurry to 50°C, then adding the curing agent, stirring to degas, and obtaining the resin composition for impregnation, which is used for impregnation treatment of the corresponding carbon fiber to obtain the carbon fiber prepreg.

[0033] Example 2

[0034] The resin composition for impregnation treatment in this example is composed of a resin slurry and a curing agent (methyl hexahydrophthalic anhydride), and the resin slurry is prepared from the following components in parts by weight: 6.5 parts of the spiro ortho carbonate dilatant monomer modified MOF derived ZnO@C composite, 33 parts of bisphenol A epoxy resin, 38 parts of bisphenol F epoxy resin, 9 parts of epoxy diluent (allyl glycidyl ether AGE), 1.5 parts of polyether modified polydimethylsiloxane dispersant, initiator (trifluoromethanesulfonic anhydride initiator); wherein the amount of the curing agent is 50% of the total amount of bisphenol A epoxy resin and bisphenol F epoxy resin; the amount of the initiator is 0.8% of the mass of the spiro ortho carbonate dilatant monomer modified MOF derived ZnO@C composite; and the rest is the same as in Example 1. The physical object before step S2 of laying and pasting (heating and forming) in this example is flat, without obvious abnormal phenomena such as edge lifting and bulging.

[0035] Example 3

[0036] The resin composition for impregnation treatment in this example is composed of a resin slurry and a curing agent (methyl hexahydrophthalic anhydride), and the resin slurry is prepared from the following components in parts by weight: 6.5 parts of the spiro ortho carbonate dilatant monomer modified MOF derived ZnO@C composite, 33 parts of bisphenol A epoxy resin, 38 parts of bisphenol F epoxy resin, 9 parts of epoxy diluent (allyl glycidyl ether AGE), 1.5 parts of polyether modified polydimethylsiloxane dispersant, initiator (trifluoromethanesulfonic anhydride initiator); wherein the amount of the curing agent is 50% of the total amount of bisphenol A epoxy resin and bisphenol F epoxy resin; the amount of the initiator is 0.8% of the mass of the spiro ortho carbonate dilatant monomer modified MOF derived ZnO@C composite; and the rest is the same as in Example 1. The physical object before step S2 of laying and pasting (heating and forming) in this example is flat, without obvious abnormal phenomena such as edge lifting and bulging.

[0037] Comparative Example 1 Based on Example 2, the resin composition for impregnation treatment in this comparative example is composed of a resin slurry and a curing agent (methyl hexahydrophthalic anhydride), and the resin slurry is composed of 33 parts of bisphenol A epoxy resin, 38 parts of bisphenol F epoxy resin, and 9 parts of epoxy diluent (allyl glycidyl ether AGE), wherein the amount of the curing agent is 50% of the total amount of bisphenol A epoxy resin and bisphenol F epoxy resin. The preparation method and carbon cloth laying process refer to Example 1; the resin used in this comparative example is a commonly used epoxy resin, and the carbon fiber prepreg used in this comparative example is equivalent to the existing carbon fiber prepreg.

[0038] Comparative Example 2 Based on Example 2, different from Example 2, the resin composition for impregnation treatment in the present comparative example is composed of resin slurry and curing agent (methyl hexahydrophthalic anhydride), the resin slurry is prepared from the following components in parts by weight: 3.2 parts of spiro ortho carbonate expansion monomer, 33 parts of bisphenol A epoxy resin, 38 parts of bisphenol F epoxy resin, 9 parts of epoxy diluent (allyl glycidyl ether AGE), 1.5 parts of polyether modified polydimethylsiloxane dispersant, initiator (triflic anhydride initiator); wherein the amount of curing agent is 50% of the total amount of bisphenol A epoxy resin and bisphenol F epoxy resin; the amount of initiator is 0.8% of the mass of spiro ortho carbonate expansion monomer; the rest is consistent with Example 2; the spiro ortho carbonate expansion monomer in the present comparative example does not use MOF derived ZnO@C composite as carrier, but is used directly, which is equivalent to using spiro ortho carbonate expansion monomer to modify the epoxy resin mixture; the present comparative example does not add MOF derived ZnO@C composite, the amount of spiro ortho carbonate expansion monomer is adjusted accordingly, and the preparation method is also adjusted accordingly, which does not include the preparation method of spiro ortho carbonate expansion monomer modified MOF derived ZnO@C composite.

[0039] Comparative Example 3 Based on Example 2, different from Example 2, the resin composition for impregnation treatment in the present comparative example is composed of resin slurry and curing agent (methyl hexahydrophthalic anhydride), the resin slurry is prepared from the following components in parts by weight: 3.5 parts of MOF derived ZnO@C composite (without amination treatment), 33 parts of bisphenol A epoxy resin, 38 parts of bisphenol F epoxy resin, 9 parts of epoxy diluent (allyl glycidyl ether AGE), 1.5 parts of polyether modified polydimethylsiloxane dispersant; wherein the amount of curing agent is 50% of the total amount of bisphenol A epoxy resin and bisphenol F epoxy resin; the present comparative example does not contain spiro ortho carbonate expansion monomer and initiator in the resin composition, and the rest is consistent with Example 2.

[0040] Comparative Example 4 Based on Example 2, different from Example 2, the present comparative example does not include initiator (triflic anhydride initiator) in the resin composition for impregnation treatment, and the rest is consistent with Example 2.

[0041] Comparative Example 5 Based on Example 2, different from Example 2, the laying process in the present comparative example lays the second carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, the fifth carbon cloth layer and the sixth carbon cloth layer from inside to outside, does not lay the first carbon cloth layer, and the second carbon cloth layer is laid first. The rest is consistent with Example 2.

[0042] Comparative Example 6 Based on Example 2, different from Example 2, in the laying process of the present comparative example, the first carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, the fifth carbon cloth layer, and the sixth carbon cloth layer are sequentially laid from the inside to the outside, and the second carbon cloth layer is not laid. The rest is consistent with Example 2.

[0043] Comparative Example 7 Based on Example 2, different from Example 2, in the laying process of the present comparative example, the first carbon cloth layer, the second carbon cloth layer, the fourth carbon cloth layer, the fifth carbon cloth layer, and the sixth carbon cloth layer are sequentially laid from the inside to the outside, and the third carbon cloth layer is not laid. The rest is consistent with Example 2.

[0044] Comparative Example 8 Based on Example 2, different from Example 2, in the laying process of the present comparative example, the first carbon cloth layer, the second carbon cloth layer, the third carbon cloth layer, the fifth carbon cloth layer, and the sixth carbon cloth layer are sequentially laid from the inside to the outside, and the fourth carbon cloth layer is not laid. The rest is consistent with Example 2.

[0045] Comparative Example 9 Based on Example 2, different from Example 2, in the laying process of the present comparative example, the first carbon cloth layer, the second carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, and the sixth carbon cloth layer are sequentially laid from the inside to the outside, and the fifth carbon cloth layer is not laid. The rest is consistent with Example 2.

[0046] Comparative Example 10 Based on Example 2, different from Example 2, in the laying process of the present comparative example, the first carbon cloth layer, the second carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, and the fifth carbon cloth layer are sequentially laid from the inside to the outside, and the sixth carbon cloth layer is not laid. The rest is consistent with Example 2.

[0047] Test Example 1 The appearance characteristics of the carbon fiber unmanned aerial vehicle arm rough product prepared in Examples 1-3 and Comparative Examples 1-10 were detected, whether there were obvious defects such as deformation, cracks, bubbles, and uneven surface, and the results are shown in Table 1; wherein the arm rough product prepared in the range of Example 2 shrinks after heating and curing, and can be directly demolded; Table 1 Appearance characteristics of carbon fiber unmanned aerial vehicle arm rough product Appearance of carbon fiber unmanned aerial vehicle arm rough product (after heat molding) Example 1 No significant defects such as deformation, cracks, bubbles, surface unevenness Example 2 No significant defects such as deformation, cracks, bubbles, surface unevenness Example 3 No significant defects such as deformation, cracks, bubbles, surface unevenness Comparative Example 1 Partial deformation, fine cracks, and surface unevenness occurred Comparative Example 2 Bulging and surface unevenness occurred Comparative Example 3 Partial warping deformation, fine cracks, and surface unevenness occurred Comparative Example 4 No significant defects such as deformation, cracks, bubbles, surface unevenness Comparative Example 5 Surface unevenness was significant Comparative Example 6 Significant cracks and pores were present Comparative Example 7 Visible twisting deformation Comparative Example 8 Visible bending deformation Comparative Example 9 Visible pores were present Comparative Example 10 Surface unevenness was significant and had a sharp burr feeling Compared with the comparative examples, the rough product prepared in the examples of the present application has no abnormal conditions on the surface except that the edge has a permissible edge that needs to be polished and other characteristics; the rough product prepared in Comparative Example 1 (unqualified) has a rough and uneven surface, and local cracks and deformation appear; the rough product prepared in Comparative Example 6 (unqualified) has obvious pores.

[0048] Test Example 2 The mechanical properties of the finished carbon fiber unmanned aerial vehicle arm product after fine grinding prepared in Examples 1-3 and Comparative Examples 1-4 and the scrap rate of 100 pieces in batch production are shown in Table 2.

[0049] Tensile strength test: refer to the test method of ASTM D3039 standard; sample preparation: cut a standard dumbbell-shaped sample (100 mm in length, 12.7 mm in width, and the actual thickness of the finished product) from each finished arm product; equipment: electronic universal testing machine (0.5 level of precision); test procedure: clamp the sample on the wedge-shaped clamp of the testing machine, ensure that the sample axis is consistent with the loading direction, set the loading speed to 2 mm / min, apply tension until the sample breaks, record the maximum load, and calculate the tensile strength, tensile strength = maximum load / original cross-sectional area of the sample; Bending strength test: refer to the test method of ASTM D790 standard; sample preparation: cut a rectangular beam sample (128 mm in length, 12.7 mm in width, and the actual thickness of the finished product) from the finished arm product; equipment: electronic universal testing machine (equipped with a three-point bending clamp); test procedure: place the sample on the three-point bending clamp with a 100 mm span, set the loading speed to 1 mm / min, apply the load at the midpoint of the span, until the sample cracks or breaks, record the maximum bending load, and calculate the bending strength, bending strength = 3xFxL / (2x b x h 2 (F is the maximum bending load, L is the span of the support, b is the width of the sample, and h is the thickness of the sample); Heat resistance test: refer to GB / T 1634.2 standard; sample: cut a 10 mm x 10 mm x 5 mm sample from the finished arm product; equipment: heat distortion temperature tester; test procedure: place the sample under a temperature rising rate of 3 ℃ / min, apply a static load of 0.45 MPa, and record the temperature when the heat distortion of the sample reaches 0.25 mm, which is the heat distortion temperature; Corrosion resistance: sample: cut a 20 mm x 20 mm x 5 mm sample from the finished arm product, and polish the surface; test medium: common working environment medium for unmanned aerial vehicles (5% NaCl solution, 0.1 mol / L HCl solution, and 0.1 mol / L NaOH solution); test procedure: completely immerse the sample in the three kinds of medium, take it out after 72 h of room temperature soaking, and observe whether there are corrosion phenomena such as bulging, delamination, discoloration, etc. on the surface; Density: refer to GB / T 1463-2005 “Fiber Reinforced Plastics Density and Relative Density Test Method”, and determine by the drainage method (immersion method); Scrap rate: produce 100 pieces of arm finished product in batch, check the appearance defects (deformation, cracks, bubbles, and uneven surface) one by one, and the finished product with appearance defects is a scrap, scrap rate = scrap number / 100 x 100%.

[0050] Table 2 Mechanical property detection and substandard rate detection results of finished products Tensile strength (MPa) Flexural strength (MPa) Heat resistance Corrosion resistance Density Defective rate Example 1 3450±50 2020±38 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm 3 ]] ≤2% Example 2 3680±45 2080±40 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm 3 ]] ≤2% Example 3 3520±55 2040±42 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm 3 ]] ≤2% Comparative Example 1 2850±60 1650±45 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm 3 ]] ＞15% Comparative Example 2 2050±55 1320±42 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm 3 ]] ＞10% Comparative Example 3 2920±58 1720±48 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm 3 ]] ＞10% Comparative Example 4 3250±50 1950±36 ＞300℃ No corrosion was observed in any of the three media 1.5-1.6 g / cm3 5-7% The application has stable forming process and low substandard rate; can prepare high-strength and light-weight unmanned aerial vehicle parts, and has good corrosion resistance and heat resistance, and is suitable for complex environments such as high temperature. The spiro orthocarbonate expansion monomer modified MOF derived ZnO@C composite in the application can effectively improve the mechanical properties of the product and reduce defects in the multi-layer lamination process.

[0051] Test Example 3 The shrinkage or expansion rate of the resin composition in Test Example 2 and Comparative Examples 1-4 was detected, and the results are shown in Table 3. Detection method: refer to standards GB / T 24148.9 and ISO 3521; the volume curing shrinkage rate of the cured resin is calculated according to the following formula: curing shrinkage rate = (1-ρbefore / ρafter) x 100%, wherein: ρbefore is the density of the resin before curing, g / cm 3 ; ρafter is the density of the resin after curing, g / cm 3 ; when the value is positive, it means that the resin shrinks after curing; when the value is negative, it means that the resin expands after curing; the density detection method of the resin is a prior art, and the content of the reference standard can be referred to, and will not be described in detail here.

[0052] Table 3 Shrinkage or expansion rate of resin composition Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Shrinkage rate -0.1%~0.1% 2.2%-2.5% -1.2%~-1% 1.5%~1.8% 0.4%~0.6% In the application, when the MOF@C carrier is absent in Comparative Example 2, the expansion behavior of the spiro orthocarbonate expansion monomer is violent and uncontrollable, and there is a significant large expansion in the middle of curing (monitored by real-time volume change), even if there is some shrinkage and slight expansion at the end, irreversible damage (bulges, unevenness) has been caused to the product.

[0053] The above only describes the preferred embodiments of the application and does not limit the protection scope of the application, and any modifications, equivalent replacements and improvements made by those skilled in the art within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A carbon fiber drone component molding process, characterized in that: Includes the following steps: S1. A heat-shrinkable polymer latex airbag that matches the shape of the drone parts is used as the mold core. S2. Carbon fiber prepreg is laid on the surface of the mold core through a multi-angle, multi-layer laying process to obtain a preform; the multi-angle, multi-layer laying process includes the following steps: laying the first carbon cloth layer, the second carbon cloth layer, the third carbon cloth layer, the fourth carbon cloth layer, the fifth carbon cloth layer, and the sixth carbon cloth layer in sequence from the inside to the outside. Both the first carbon cloth layer and the sixth carbon cloth layer are composed of 3K twill-200 carbon fiber prepreg; Both the second and fifth carbon cloth layers are composed of ±C45°-150 carbon fiber prepreg; The third carbon cloth layer is composed of C0°-150 carbon fiber prepreg; The fourth carbon cloth layer is composed of C90°-150 carbon fiber prepreg; S3. The preform is formed on a hot press, and after the mold core is removed, a rough carbon fiber drone part is obtained. S4. Grind and refine the rough carbon fiber drone parts to obtain the finished carbon fiber drone parts.

2. The carbon fiber UAV component molding process according to claim 1, characterized in that: The ±C45°-150 carbon fiber prepreg has fibers arranged in two interlaced directions: 45° and -45°.

3. The carbon fiber drone component molding process according to claim 1, characterized in that: The drone parts are arms or landing gear.

4. The carbon fiber drone component molding process according to claim 1, characterized in that: The 3K twill-200 carbon fiber prepreg, ±C45°-150 carbon fiber prepreg, C0°-150 carbon fiber prepreg, and C90°-150 carbon fiber prepreg are all obtained by impregnation treatment with the same resin composition.

5. The carbon fiber drone component molding process according to claim 4, characterized in that: The resin composition comprises a resin slurry and a curing agent; the resin slurry is prepared from the following components in parts by weight: 5.5-7.5 parts of spirocyclic orthocarbonate expanded monomer modified MOF-derived ZnO@C composite, 30-35 parts of bisphenol A epoxy resin, 35-40 parts of bisphenol F epoxy resin, 8-10 parts of epoxy diluent, 1-2 parts of polyether-modified polydimethylsiloxane dispersant, and initiator; wherein, the amount of curing agent added is 50% of the total amount of bisphenol A epoxy resin and bisphenol F epoxy resin; the amount of initiator added is 0.8% of the mass of spirocyclic orthocarbonate expanded monomer modified MOF-derived ZnO@C composite.

6. The carbon fiber drone component molding process according to claim 5, characterized in that: The spirocyclic orthocarbonate expanded monomer-modified MOF-derived ZnO@C complex was prepared by the following method: The MOF-74 (Zn) precursor was placed in a tube furnace and calcined under argon protection. After cooling, the MOF-derived ZnO@C complex was obtained. The MOF-derived ZnO@C complex was dispersed in toluene, stirred evenly, and then 3-aminopropyltriethoxysilane and glacial acetic acid were added. The mixture was heated and reacted, and then filtered to obtain the aminated MOF-derived ZnO@C complex. Spirocyclic orthocarbonate expanding monomer and 3-glycidyl etheroxypropyltrimethoxysilane were reacted under heating in the presence of dibutyltin dilaurate catalysis to obtain an intermediate reactant; the aminated ZnO@C complex was dispersed in anhydrous toluene, the intermediate reactant and triethylamine were added, the mixture was heated, filtered, washed and dried to obtain a MOF-derived ZnO@C complex modified by spirocyclic orthocarbonate expanding monomer; wherein the spirocyclic orthocarbonate expanding monomer was 3,9-dihydroxymethyl-3',9'-diethyl-1,5,7,11-tetraoxaspiro[5,5]undecane.

7. The carbon fiber UAV component molding process according to claim 5, characterized in that: The epoxy diluent is allyl glycidyl ether (AGE).

8. The carbon fiber drone component molding process according to claim 5, characterized in that: The curing agent is methyl hexahydrophthalic anhydride, and the initiator is trifluoromethanesulfonic anhydride initiator.

9. The carbon fiber UAV component molding process according to claim 5, characterized in that: The resin composition is prepared by the following method: Bisphenol A epoxy resin, bisphenol F epoxy resin and epoxy diluent are mixed and mechanically stirred at room temperature for 15-20 minutes to obtain a uniform resin base liquid; polyether-modified polydimethylsiloxane dispersant and spirocyclic orthocarbonate expanded monomer-modified MOF-derived ZnO@C complex are added to the resin base liquid, transferred to a high-speed disperser and dispersed at high speed by shearing for 30-45 minutes at room temperature to obtain a premixed slurry; trifluoromethanesulfonic anhydride initiator is added to the premixed slurry, and stirring is continued at room temperature for 10-15 minutes to obtain a resin slurry; before use, the resin slurry is preheated to 45-50°C, then a curing agent is added, and stirring is performed to remove bubbles to obtain the resin composition.

10. The carbon fiber drone component molding process according to claim 1, characterized in that: In step S3, the preform is hot-pressed at a temperature of 145-150℃. After removing the mold core, a rough carbon fiber drone part is obtained.