A CF / PEEK composite material and preparation method thereof

Abstract

The invention discloses a CF / PEEK composite material and a preparation method thereof, and relates to the field of composite materials. The CF / PEEK composite material is obtained by molding after being sequentially stacked by PEEK sheets, modified CF layers, and PEEK sheets, and the modified CF layers are obtained by being modified by modified epoxy resin by CF layers, and the PEEK sheets are prepared by PEEK resin, compatibilizer and other functional additives, and the content of compatibilizer is 4 5% of the total weight of PEEK resin, and the compatibilizer adopts aminosilane coupling agent. The application first uses modified epoxy resin to modify the CF layer, and then with the PEEK sheet molded composite prepared by PEEK resin, compatibilizer and other functional additives, by the joint action of compatibilizer in modified CF layer and PEEK sheet, the bonding tightness of PEEK resin and CF is improved, which is conducive to enhancing the tensile strength and bending resistance of the CF / PEEK composite material.

Description

Technical Field

[0001] The present application relates to the field of composite materials, and in particular to a CF / PEEK composite material and a preparation method thereof. Background Art

[0002] Carbon fiber (CF) and polyetheretherketone (PEEK) composites are widely used in high-performance structural parts due to their light weight and high strength. However, due to the characteristics of the molecular structure of PEEK resin, its wettability with the CF surface is poor, making it difficult for the two to form a tight and stable bonding interface. This problem directly affects the tensile and bending properties of CF / PEEK composites, limiting their promotion and use in high-end application scenarios with high mechanical performance requirements (such as aerospace, automotive manufacturing, medical equipment, AI robot manufacturing, etc.). Summary of the Invention

[0003] In order to improve the problem of poor mechanical properties of existing CF / PEEK composite materials, the present application provides a CF / PEEK composite material and a preparation method thereof.

[0004] In the first aspect, the present application provides a CF / PEEK composite material adopting the following technical solution:

[0005] A CF / PEEK composite material is obtained by sequentially stacking a PEEK sheet, a modified CF layer, and a PEEK sheet and then molding them. The modified CF layer is obtained by modifying a CF layer with a modified epoxy resin. The PEEK sheet is made of PEEK resin, a compatibilizer, and other functional additives. The content of the compatibilizer is 4-5% of the total weight of the PEEK resin. The compatibilizer is an aminosilane coupling agent.

[0006] In this application, the CF layer is first modified with a modified epoxy resin, and then molded and compounded with a PEEK sheet made of PEEK resin, a compatibilizer, and other functional additives. Through the combined action of the modified CF layer and the compatibilizer in the PEEK sheet, the bonding tightness between the PEEK resin and the CF can be improved, which is beneficial to enhancing the tensile and bending properties of the CF / PEEK composite material.

[0007] In some specific embodiments, the aminosilane coupling agent is at least one of N-2-aminoethyl-3-aminopropyltrimethoxysilane and N-2-aminoethyl-3-aminopropyltriethoxysilane.

[0008] In some specific embodiments, the other functional additives include ultra-high molecular weight silicone masterbatch, and the content of the ultra-high molecular weight silicone masterbatch is 1-1.5% of the total weight of the PEEK resin.

[0009] In the present application, adding ultra-high molecular weight silicone masterbatch to the PEEK sheet can improve the processing performance of the PEEK sheet, and at the same time, can also improve the tensile properties and bending resistance of the CF / PEEK composite material.

[0010] In some specific embodiments, the raw materials for preparing the modified epoxy resin include bisphenol A epoxy resin and silicone-modified hydroxy acrylic resin, and the weight ratio of the bisphenol A epoxy resin to the silicone-modified hydroxy acrylic resin is (1-1.5):1.

[0011] In this application, the modified epoxy resin adopts a composition with a specific ratio of bisphenol A epoxy resin and silicone modified acrylic resin. On the one hand, it can improve the wetting and adhesion strength of the modified epoxy resin to the CF layer, and on the other hand, it can promote the close bonding between the PEEK sheet and the CF layer, which is beneficial to the improvement of the tensile properties and bending resistance of the CF / PEEK composite material.

[0012] In some specific embodiments, the raw materials for preparing the silicone-modified hydroxy acrylic resin include 35-45 parts by weight of hydroxy acrylate monomer, 5.8-6.2 parts by weight of side chain acrylate modified silicone oil, 30-40 parts by weight of acrylate monomer, 1-1.5 parts by weight of initiator, 0.5-1 parts by weight of emulsifier and 100 parts by weight of water.

[0013] Ultra-high molecular weight silicone masterbatch is added to the PEEK sheet. At the same time, in the modified epoxy resin used to modify the CF layer, the silicone-modified hydroxy acrylic resin is obtained by modifying the acrylic resin with side-chain acrylate-modified silicone oil. This is conducive to obtaining a CF / PEEK composite material with a smooth surface and no shrinkage holes. At the same time, the tensile strength and flexural strength of the CF / PEEK composite material can be further improved.

[0014] In some specific embodiments, the hydroxyacrylate monomer is at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, and hydroxybutyl acrylate.

[0015] In some specific embodiments, the acrylic acid ester monomer is at least one of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, and butyl methacrylate.

[0016] In some specific embodiments, the preparation method of the organosilicon-modified hydroxy acrylic resin is as follows:

[0017] Add the emulsifier to water and stir until dissolved. Then add the side chain acrylate modified silicone oil and acrylate monomer. After stirring evenly, add the hydroxy acrylate monomer and initiator dropwise. Heat to 85-95°C and stir to react for 3.5-4.5 hours to obtain the silicone modified hydroxy acrylic resin.

[0018] In the present application, the organic silicone hydroxy acrylic resin prepared by the above method is conducive to obtaining a CF / PEEK composite material with a smooth surface, no shrinkage holes, and good tensile and bending properties.

[0019] In a second aspect, the present application provides a method for preparing a CF / PEEK composite material using the following technical solution:

[0020] A method for preparing a CF / PEEK composite material comprises the following steps:

[0021] Evenly spraying the surface of the CF layer with modified epoxy resin, and then drying it at 100-120° C. to obtain a modified CF layer;

[0022] The PEEK resin, compatibilizer and other functional additives are uniformly mixed to obtain a premix, and then the premix is melt-extruded at 380-390° C. and cast into a sheet to obtain a PEEK sheet with a thickness of 1-2 mm;

[0023] The PEEK sheets are stacked on the upper and lower sides of the modified CF layer, heated to 380-390° C., kept warm for 20-30 minutes, and then pressurized to 2-3 MPa and molded for 30-40 seconds to obtain a CF / PEEK composite material.

[0024] In the present application, in the CF / PEEK composite material prepared by the above method, the PEEK resin is embedded in the gaps of the modified CF layer and is tightly combined with the CF material, thereby obtaining a CF / PEEK composite material with excellent tensile and bending properties.

[0025] In some specific embodiments, when preparing the modified CF layer, the spraying amount of the modified epoxy resin is 2.0-2.5 g / m 2 .

[0026] In summary, this application has at least the following beneficial technical effects:

[0027] (1) In the present application, the CF layer is first modified with a modified epoxy resin, and then molded and compounded with a PEEK sheet made of PEEK resin, a compatibilizer, and other functional additives. Through the combined action of the modified CF layer and the compatibilizer in the PEEK sheet, the bonding tightness between the PEEK resin and the CF is improved, which is beneficial to enhancing the tensile and bending properties of the CF / PEEK composite material.

[0028] (2) In the present application, ultra-high molecular weight silicone masterbatch is added to the PEEK sheet. At the same time, in the modified epoxy resin used to modify the CF layer, the silicone-modified hydroxy acrylic resin is obtained by modifying the acrylic resin with a side-chain acrylate-modified silicone oil. This is beneficial for obtaining a CF / PEEK composite material with a smooth surface and no shrinkage cavities. At the same time, the tensile strength and flexural strength of the CF / PEEK composite material can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the superposition of various materials of the CF / PEEK composite material before molding in each embodiment of the present application.

[0030] 1. PEEK sheet; 2. Modified CF layer. DETAILED DESCRIPTION

[0031] The present application is further described below in conjunction with specific experiments.

[0032] Example

[0033] [Example 1]

[0034] A CF / PEEK composite material is obtained by sequentially stacking a PEEK sheet 1, a modified CF layer 2, and the PEEK sheet 1 and then subjecting them to molding. The modified CF layer 2 is obtained by modifying a CF layer with a modified epoxy resin. The PEEK sheet 1 is prepared from PEEK resin, a compatibilizer, and an ultra-high molecular weight silicone masterbatch.

[0035] The carbon fiber fabric used in the CF layer is a plain weave fabric woven from T300 carbon fiber manufactured by Toray Industries, Japan. The modified epoxy resin includes a bisphenol A epoxy resin and a silicone-modified hydroxy acrylic resin, with the weight ratio of the bisphenol A epoxy resin to the silicone-modified hydroxy acrylic resin being 1:1. Specifically, the bisphenol A epoxy resin is bisphenol A epoxy resin E55, and the preparation method of the silicone-modified hydroxy acrylic resin is as follows:

[0036] 0.5 kg of OP-10 was added to 100 kg of water and stirred until dissolved. Then, 5.8 kg of side chain acrylate-modified silicone oil IOTA 170 and 30 kg of ethyl acrylate were added and stirred evenly. Then, 35 kg of hydroxyethyl acrylate and 1 kg of 0.5% ammonium persulfate aqueous solution were added dropwise. The temperature was raised to 85 ° C and stirred for 4.5 hours to obtain a silicone-modified hydroxy acrylic resin.

[0037] In addition, the PEEK resin used is Zhongyan PEEK-300G; the compatibilizer specifically uses N-2-aminoethyl-3-aminopropyltrimethoxysilane, and the content of N-2-aminoethyl-3-aminopropyltrimethoxysilane is 4% of the total weight of the PEEK resin; the ultra-high molecular weight silicone masterbatch uses the ultra-high molecular weight silicone masterbatch of the new material model MB3225 from Leifuss, and the content of the ultra-high molecular weight silicone masterbatch is 1% of the total weight of the PEEK resin.

[0038] In this embodiment, the preparation method of the CF / PEEK composite material includes the following steps:

[0039] S1. Spray modified epoxy resin evenly on the surface of CF layer. The spraying amount of modified epoxy resin is 2.0g / m 2 , and then dried at 100°C to obtain a modified CF layer 2;

[0040] S2, mixing PEEK resin, a compatibilizer, and an ultra-high molecular weight silicone masterbatch to obtain a premix, and then melt-extruding the premix at 380° C. and casting a sheet to obtain a PEEK sheet 1 with a thickness of 2 mm;

[0041] S3. PEEK sheet 1 is superimposed on the upper and lower sides of modified CF layer 2, the temperature is raised to 380°C, kept warm for 30 minutes, and then pressurized to 2 MPa and molded for 40 seconds to obtain CF / PEEK composite material.

[0042] [Example 2]

[0043] A CF / PEEK composite material is obtained by sequentially stacking a PEEK sheet 1, a modified CF layer 2, and the PEEK sheet 1 and then molding. The modified CF layer 2 is obtained by modifying the CF layer with a modified epoxy resin. The PEEK sheet 1 is made of PEEK resin, a compatibilizer, and an ultra-high molecular weight silicone masterbatch.

[0044] The carbon fiber fabric used in the CF layer is a plain weave fabric woven from model T300 carbon fiber produced by Toray Industries, Japan. The modified epoxy resin includes bisphenol A epoxy resin and silicone-modified hydroxy acrylic resin, with the weight ratio of bisphenol A epoxy resin to silicone-modified hydroxy acrylic resin being 1.5:1. Specifically, the bisphenol A epoxy resin is bisphenol A epoxy resin E55, and the preparation method of the silicone-modified hydroxy acrylic resin is as follows:

[0045] 1 kg of OP-10 was added to 100 kg of water and stirred until dissolved. Then, 6.2 kg of side chain acrylate-modified silicone oil IOTA 170 and 40 kg of ethyl acrylate were added and stirred evenly. Then, 45 kg of hydroxyethyl acrylate and 1.5 kg of 0.5% ammonium persulfate aqueous solution were added dropwise. The temperature was raised to 95 ° C and stirred for 3.5 hours to obtain a silicone-modified hydroxy acrylic resin.

[0046] In addition, the PEEK resin used is Zhongyan PEEK-300G; the compatibilizer specifically uses N-2-aminoethyl-3-aminopropyltriethoxysilane, and the content of N-2-aminoethyl-3-aminopropyltriethoxysilane is 5% of the total weight of the PEEK resin; the ultra-high molecular weight silicone masterbatch uses the ultra-high molecular weight silicone masterbatch of the new material model MB3225 from Leifuss, and the content of the ultra-high molecular weight silicone masterbatch is 1.5% of the total weight of the PEEK resin.

[0047] In this embodiment, the preparation method of the CF / PEEK composite material includes the following steps:

[0048] S1. Spray modified epoxy resin evenly on the surface of CF layer. The spraying amount of modified epoxy resin is 2.5g / m 2 , and then dried at 120°C to obtain a modified CF layer 2;

[0049] S2, mixing PEEK resin, a compatibilizer, and an ultra-high molecular weight silicone masterbatch to obtain a premix, and then melt-extruding the premix at 390° C. and casting a sheet to obtain a PEEK sheet 1 with a thickness of 2 mm;

[0050] S3. PEEK sheet 1 is superimposed on the upper and lower sides of modified CF layer 2, the temperature is raised to 390°C, kept warm for 20 minutes, and then pressurized to 3 MPa and molded for 30 seconds to obtain a CF / PEEK composite material.

[0051] [Example 3]

[0052] A CF / PEEK composite material, which differs from [Example 1] in that: when preparing the silicone-modified hydroxy acrylic resin, the side chain acrylate-modified silicone oil IOTA 170 is replaced by an equal amount of end-vinyl and end-hydroxy silicone oil SC-VH10 (from Kmik).

[0053] [Example 4]

[0054] A CF / PEEK composite material, which differs from [Example 1] in that:

[0055] The modified epoxy resin includes a bisphenol A epoxy resin and a hydroxy acrylic resin. The preparation method of the hydroxy acrylic resin is as follows: 0.5 kg of OP-10 is added to 100 kg of water and stirred until dissolved, followed by adding 35.8 kg of ethyl acrylate. After stirring evenly, 35 kg of hydroxyethyl acrylate and 1 kg of a 0.5% ammonium persulfate aqueous solution are dropwise added, the temperature is raised to 85° C., and the mixture is stirred for 4.5 hours to obtain the hydroxy acrylic resin.

[0056] [Example 5]

[0057] A CF / PEEK composite material, which differs from [Example 1] in that the ultra-high molecular weight silicone masterbatch is replaced by an equal amount of nano-silicon dioxide.

[0058] Comparative Example

[0059] [Comparative Example 1]

[0060] A CF / PEEK composite material differs from Example 1 in that the step of modifying the CF layer in S1 is omitted. In step S3, PEEK sheets are directly stacked on the upper and lower sides of the CF layer, the temperature is raised to 380°C, the temperature is kept for 30 minutes, and then a pressure of 2 MPa is applied and molded for 40 seconds to obtain a CF / PEEK composite material.

[0061] [Comparative Example 2]

[0062] A CF / PEEK composite material, which differs from [Example 1] in that: in S1, bisphenol A epoxy resin E55 is directly used to modify the CF layer.

[0063] [Comparative Example 3]

[0064] A CF / PEEK composite material, which differs from [Example 1] in that no compatibilizer is added during the preparation of the PEEK sheet.

[0065] Performance testing

[0066] 1. Surface quality: Observe the surface of the CF / PEEK composite materials prepared in each embodiment and comparative example to see whether they are smooth or have shrinkage cavities.

[0067] 2. Tensile strength: The tensile strength of the CF / PEEK composite materials prepared in each example and comparative example was tested with reference to ASTM D638.

[0068] 3. Flexural strength: The flexural strength of the CF / PEEK composite materials prepared in each example and comparative example was tested with reference to ASTM D7264.

[0069] Table 1

[0070]

[0071] Combining Example 1 with Comparative Examples 1-2 and the data in Table 1, it can be seen that when the PEEK sheet is made of PEEK resin, compatibilizer and ultra-high molecular weight silicone masterbatch, not modifying the CF layer or only using bisphenol A epoxy resin to modify the CF layer is not conducive to improving the tensile strength and flexural strength of the CF / PEEK composite material. However, using a modified epoxy resin containing bisphenol A epoxy resin and silicone-modified hydroxy acrylic resin to modify the CF layer can effectively improve the tensile strength and flexural strength of the CF / PEEK composite material.

[0072] Combining Example 1 and Comparative Example 3 and the data in Table 1, it can be seen that when the CF layer is modified by using a modified epoxy resin comprising bisphenol A epoxy resin and silicone-modified hydroxy acrylic resin, but no compatibilizer is added to the PEEK sheet, the tensile strength and flexural strength of the CF / PEEK composite material are both reduced, indicating that the addition of the compatibilizer is beneficial to improving the tensile strength and flexural strength of the CF / PEEK composite material.

[0073] Combining Example 1 and Example 3 and the data in Table 1, it can be seen that among the modified epoxy resins, the silicone-modified hydroxy acrylic resin obtained by modifying acrylic resin with side-chain acrylate-modified silicone oil is beneficial for obtaining a CF / PEEK composite material with a smooth surface and no shrinkage cavities. At the same time, the tensile strength and flexural strength of the CF / PEEK composite material can be further improved.

[0074] Combining Example 1 and Example 4 and the data in Table 1, it can be seen that compared with modifying the CF layer with a modified epoxy resin comprising bisphenol A epoxy resin and silicone-modified hydroxy acrylic resin, modifying the CF layer with a modified epoxy resin comprising bisphenol A epoxy resin and hydroxy acrylic resin, the tensile strength and flexural strength of the CF / PEEK composite material are reduced. At the same time, the surface of the CF / PEEK composite material is uneven and has shrinkage holes.

[0075] Combining Example 1 and Example 5 and the data in Table 1, it can be seen that after the ultra-high molecular weight silicone masterbatch in the PEEK sheet is replaced by nano-silica, the tensile strength and flexural strength of the CF / PEEK composite material decrease. At the same time, the surface of the CF / PEEK composite material is uneven and has shrinkage holes.

[0076] This specific implementation manner is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the specific implementation manner as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A CF / PEEK composite material, characterized by: The PEEK sheet (1), the modified CF layer (2), and the PEEK sheet (1) are sequentially stacked and then molded, wherein the modified CF layer (2) is obtained by modifying the CF layer with a modified epoxy resin, and the PEEK sheet (1) is made of PEEK resin, a compatibilizer and other functional additives, wherein the content of the compatibilizer is 4-5% of the total weight of the PEEK resin, and the compatibilizer is an aminosilane coupling agent; The other functional additives include ultra-high molecular weight silicone masterbatch, and the content of the ultra-high molecular weight silicone masterbatch is 1-1.5% of the total weight of the PEEK resin; The raw materials for preparing the modified epoxy resin include bisphenol A epoxy resin and organosilicon-modified hydroxy acrylic resin, and the weight ratio of the bisphenol A epoxy resin to the organosilicon-modified hydroxy acrylic resin is (1-1.5):1; The raw materials for preparing the silicone-modified hydroxy acrylic resin include 35-45 parts by weight of hydroxy acrylate monomer, 5.8-6.2 parts by weight of side chain acrylate modified silicone oil, 30-40 parts by weight of acrylate monomer, 1-1.5 parts by weight of initiator, 0.5-1 parts by weight of emulsifier and 100 parts by weight of water.

2. The CF / PEEK composite material according to claim 1, characterized in that: The aminosilane coupling agent is at least one of N-2-aminoethyl-3-aminopropyltrimethoxysilane and N-2-aminoethyl-3-aminopropyltriethoxysilane.

3. The CF / PEEK composite material according to claim 1, characterized in that: The hydroxy acrylate monomer is at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, and hydroxybutyl acrylate.

4. The CF / PEEK composite material according to claim 1, characterized in that: The acrylic acid ester monomer is at least one of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, and butyl methacrylate.

5. The CF / PEEK composite material according to claim 1, characterized in that: The preparation method of the silicone-modified hydroxy acrylic resin is as follows: add the emulsifier into water and stir until dissolved, then add the side chain acrylate-modified silicone oil and acrylate monomer, stir evenly, add the hydroxy acrylate monomer and initiator dropwise, heat to 85-95°C, stir and react for 3.5-4.5 hours to obtain the silicone-modified hydroxy acrylic resin.

6. A method for preparing a CF / PEEK composite material according to any one of claims 1 to 5, characterized in that: The following steps are involved: The modified epoxy resin is evenly sprayed onto the surface of the CF layer, and then dried at 100-120°C to obtain a modified CF layer (2); the PEEK resin, compatibilizer and other functional additives are evenly mixed to obtain a premix, and then the premix is melt-extruded at 380-390°C and cast to obtain a PEEK sheet (1) with a thickness of 1-2 mm; the PEEK sheet (1) is overlapped on the upper and lower sides of the modified CF layer (2), the temperature is raised to 380-390°C, the temperature is kept for 20-30 minutes, and then a pressure of 2-3 MPa is applied and molded for 30-40 seconds to obtain a CF / PEEK composite material.

7. The method for preparing a CF / PEEK composite material according to claim 6, wherein: When preparing the modified CF layer (2), the spraying amount of the modified epoxy resin is 2.0-2.5g / m 2 .

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