Composite shielding material and preparation method and application thereof
By combining modified graphene oxide with fluorocarbon resin and optimizing the interface structure, the problems of agglomeration and poor corrosion resistance of composite shielding materials were solved, achieving high-performance hydrophobic and electromagnetic shielding effects.
Patent Information
- Application Number
- CN202511052474.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-29
- Publication Date
- 2025-10-31
AI Technical Summary
Existing composite shielding materials are prone to agglomeration and have poor corrosion resistance. The poor interfacial compatibility between graphene and fluorocarbon resin results in limited performance improvement.
Modified graphene oxide is combined with fluorocarbon resin and linked by Si-OC bonds to optimize the interface structure. Silane coupling agents with hydrophobic groups are used to improve dispersibility. Through molecular structure design and process parameter optimization, a multifunctional integrated solution of hydrophobicity, corrosion resistance, and electromagnetic shielding is achieved.
The dispersibility and interfacial bonding of graphene in resin were improved, the shielding performance of the coating was optimized, and the synergistic improvement of superhydrophobic properties and electromagnetic shielding effectiveness was achieved.
Abstract
Description
Technical Field
[0001] This application belongs to the field of anti-corrosion materials technology, specifically relating to a composite shielding material, its preparation method, and its application. Background Technology
[0002] Fluorocarbon resins are widely used in anti-corrosion and shielding coatings in aerospace, marine engineering, and electronic equipment due to their excellent weather resistance, chemical stability, and self-cleaning properties. However, pure fluorocarbon resins have limited mechanical strength, conductivity, and electromagnetic shielding performance, making it difficult to meet the requirements of highly corrosive environments or high-frequency electromagnetic interference scenarios. Therefore, researchers often modify them by adding conductive fillers (such as carbon nanotubes and metal particles), but traditional fillers suffer from poor dispersibility and coating embrittlement due to high addition amounts.
[0003] Graphene, as a two-dimensional nanomaterial, possesses high specific surface area, excellent electrical conductivity, and mechanical properties, making it an ideal filler for reinforcing fluorocarbon resins. However, the poor interfacial compatibility between graphene and fluorocarbon resins, coupled with its tendency to agglomerate, limits performance improvement. Furthermore, the inertness of the graphene surface makes it difficult to form effective chemical bonds with the resin matrix, resulting in low interfacial stress transfer efficiency. Current technologies often employ graphene oxide modified with silane coupling agents to improve dispersibility; however, excessive oxidation introduces a large number of hydrophilic oxygen-containing groups (such as carboxyl and hydroxyl groups), increasing the coating's hygroscopicity and thus weakening its anti-corrosion performance. Therefore, balancing the degree of graphene oxidation and optimizing its interfacial structure with fluorocarbon resins has become a key challenge in developing high-performance composite shielding materials. Summary of the Invention
[0004] This application provides a composite shielding material, its preparation method, and its application, aiming to solve the problems of easy agglomeration and poor corrosion resistance of existing composite shielding materials.
[0005] The first aspect of this application provides a composite shielding material, comprising fluorocarbon resin and modified graphene oxide;
[0006] The modified graphene oxide comprises graphene oxide and a silane coupling agent containing hydrophobic groups, wherein the graphene oxide and the silane coupling agent containing hydrophobic groups are connected by Si-OC bonds.
[0007] The oxygen content of the graphene oxide is 5-10 wt%.
[0008] According to some embodiments of the composite shielding material described in this application, the mass ratio of the fluorocarbon resin to the modified graphene oxide is (9-20):1.
[0009] According to some embodiments of the composite shielding material described in this application, the mass ratio of the modified graphene oxide to the silane coupling agent containing hydrophobic groups in the modified graphene oxide is (1-10):1.
[0010] According to some embodiments of the composite shielding material described in this application, the silane coupling agent containing hydrophobic groups includes tridecafluorooctyltriethoxysilane and / or heptadecafluorodecyltrimethoxysilane.
[0011] According to some embodiments of the composite shielding material described in this application, the fluorocarbon resin includes FEVE-type fluorocarbon resin.
[0012] This application also provides a method for preparing the composite shielding material described in the first aspect of this application, including the following steps:
[0013] (1) Mix the silane coupling agent and solvent to obtain a mixture, and adjust the pH of the mixture to acidic for hydrolysis;
[0014] (2) The hydrolyzed silane coupling agent mixture and graphene oxide were mixed and the two were grafted through Si-OC bonds to obtain modified graphene oxide.
[0015] (3) The modified graphene oxide, fluorocarbon resin and dispersant are mixed to obtain the composite shielding material.
[0016] According to some embodiments of the preparation method of the composite shielding material described in this application, in step (1), the solvent includes one or more of water, methanol and ethanol.
[0017] According to some embodiments of the preparation method of the composite shielding material described in this application, in step (1), hydrochloric acid solution is used to adjust the pH of the mixture; and the pH value is adjusted to 4-5.
[0018] According to some embodiments of the preparation method of the composite shielding material described in this application, in step (1), the hydrolysis temperature is 30-45℃ and the hydrolysis time is 20-40min.
[0019] According to some embodiments of the preparation method of the composite shielding material described in this application, in step (2), the mixing temperature is 60-80℃ and the mixing time is 6-12h.
[0020] According to some embodiments of the preparation method of the composite shielding material described in this application, in step (3), the dispersant includes BYK series dispersants.
[0021] According to some embodiments of the method for preparing the composite shielding material described in this application, in step (3), the mixing includes ultrasonic mixing.
[0022] According to some embodiments of the preparation method of the composite shielding material described in this application, the BYK series dispersant includes one or more of BYK-220S dispersant, BYK-110 dispersant and BYK-163 dispersant.
[0023] According to some embodiments of the preparation method of the composite shielding material described in this application, the amount of dispersant added is 0.1%-1% of the weight of the fluorocarbon resin;
[0024] According to some embodiments of the preparation method of the composite shielding material described in this application, the ultrasonic power of the ultrasonic mixing is 200-500W, and the ultrasonic mixing time is 30-60min.
[0025] The third aspect of this application provides an application of the composite shielding material described in the first aspect of this application or the composite shielding material prepared by the method described in the second aspect of this application in aerospace, marine engineering, and corrosion protection and shielding of electronic equipment.
[0026] According to some embodiments of the application described in this application, the method of the application includes coating the anti-corrosion shielding material onto the surface of the material to be protected against corrosion, curing it, and obtaining an anti-corrosion shielding coating.
[0027] According to some embodiments of the application described in this application, the curing temperature is 180-200°C and the curing time is 25-35 min.
[0028] According to some embodiments of the application described in this application, the thickness of the anti-corrosion shielding coating is 40-60 μm.
[0029] The beneficial effects of this application include: the synergistic effect of fluorocarbon resin and modified graphene oxide in the composite shielding material described in this application can reduce the surface energy of the coating and achieve superhydrophobic properties, thereby creating a dense interface on the coating surface to block water and oxygen permeation. Furthermore, the moderate conductivity and interfacial polarization effect of the modified graphene oxide material enable the composite shielding material to have excellent electromagnetic shielding performance. Detailed Implementation
[0030] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.
[0031] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0032] This application provides a composite shielding material comprising fluorocarbon resin and modified graphene oxide;
[0033] The modified graphene oxide comprises graphene oxide and a silane coupling agent containing hydrophobic groups, wherein the graphene oxide and the silane coupling agent containing hydrophobic groups are connected by Si-OC bonds.
[0034] The oxygen content of the graphene oxide is 5-10 wt%; for example, 5 wt%, 6 wt%, 8 wt%, 10 wt%, etc.
[0035] The fluorocarbon resin and modified graphene oxide of the composite shielding material described in this application work synergistically to reduce the surface energy of the coating, achieving superhydrophobic properties and creating a dense interface on the coating surface to block water and oxygen penetration. Furthermore, the moderate conductivity and interfacial polarization effect of the modified graphene oxide material give the composite shielding material excellent electromagnetic shielding performance.
[0036] In some embodiments of this application, the mass ratio of the fluorocarbon resin to the modified graphene oxide is (9-20):1; for example, 9:1, 10:1, 12:1, 15:1, 18:1, 20:1, etc.
[0037] The composite shielding material described in this application achieves a multifunctional integrated composite shielding material with hydrophobicity, corrosion resistance, and electromagnetic shielding through molecular structure design and process parameter optimization (the ratio of raw materials). The hydrophobic silane chains and fluorocarbon resin synergistically reduce the surface energy of the coating, achieving superhydrophobic properties; the dense graphene network and chemically bonded interfaces block water and oxygen permeation; and the moderate conductivity of partially oxidized graphene and the interfacial polarization effect synergistically enhance electromagnetic shielding effectiveness.
[0038] In some embodiments of this application, the mass ratio of the modified graphene oxide to the silane coupling agent containing hydrophobic groups is (1-10):1, for example, 1:1, 2:1, 5:1, 6:1, 8:1, 10:1, etc.
[0039] In some embodiments of this application, the silane coupling agent containing hydrophobic groups includes tridecafluorooctyltriethoxysilane and / or heptadecafluorodecyltrimethoxysilane; the chemical bond energy of fluorine atoms is high, and the use of fluorinated silane coupling agents can further improve the UV aging resistance of the coating.
[0040] In some embodiments of this application, the fluorocarbon resin includes FEVE-type fluorocarbon resin.
[0041] This application also provides a method for preparing the composite shielding material described in the first aspect of this application, including the following steps:
[0042] (1) Mix the silane coupling agent and solvent to obtain a mixture, and adjust the pH of the mixture to acidic for hydrolysis;
[0043] (2) The hydrolyzed silane coupling agent mixture and graphene oxide were mixed and the two were grafted through Si-OC bonds to obtain modified graphene oxide.
[0044] (3) The modified graphene oxide, fluorocarbon resin and dispersant are mixed to obtain the composite shielding material.
[0045] The modified graphene oxide in the composite shielding material described in this application is linked to the fluorocarbon resin by chemical bonds, which can effectively improve the dispersibility of graphene in the resin and enhance the interfacial bonding force, thereby optimizing the overall shielding performance of the coating.
[0046] In some embodiments of this application, in step (1), the solvent includes one or more of water, methanol, and ethanol.
[0047] In some embodiments of this application, in step (1), hydrochloric acid solution is used to adjust the pH of the mixture; and the pH value is adjusted to 4-5.
[0048] In some embodiments of this application, in step (1), the hydrolysis temperature is 30-45°C, such as 30°C, 35°C, 38°C, 43°C, 45°C, etc., and the hydrolysis time is 20-40 min; such as 20 min, 25 min, 28 min, 33 min, 37 min, 40 min, etc.
[0049] In some embodiments of this application, in step (2), the mixing temperature is 60-80°C, such as 60°C, 65°C, 68°C, 73°C, 76°C, 80°C, etc., and the mixing time is 6-12h, such as 6h, 8h, 9h, 10h, 12h, etc.
[0050] In some embodiments of this application, the method for preparing graphene oxide includes the following steps: preparation using the Hummers method: graphene oxide is prepared using graphite, concentrated sulfuric acid, potassium permanganate, sodium nitrate, hydrogen peroxide, and hydrochloric acid as raw materials; graphene oxide is mixed with ascorbic acid, and the graphene oxide is reduced at 40-60°C for a reduction time of 30-120 min to obtain graphene oxide with an oxygen content of 5wt%-10wt%.
[0051] In some embodiments of this application, in step (3), the dispersant includes BYK series dispersants.
[0052] In some embodiments of this application, the mixing in step (3) includes ultrasonic mixing.
[0053] In some embodiments of this application, the BYK series dispersants include one or more of BYK-220S dispersant, BYK-110 dispersant, and BYK-163 dispersant.
[0054] In some embodiments of this application, the amount of dispersant added is 0.1%-1% of the weight of the fluorocarbon resin; for example, 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 1%, etc. Excessive addition of dispersant can lead to decreased system stability, flocculation or sedimentation, and reduced performance, hindering coating curing, etc.; insufficient dispersant can cause filler precipitation.
[0055] In some embodiments of this application, the ultrasonic power of the ultrasonic mixing is 200-500W, such as 200W, 260W, 290W, 310W, 360W, 430W, 470W, 500W, etc., and the ultrasonic mixing time is 30-60min; such as 30min, 38min, 43min, 56min, 60min, etc.
[0056] This application also provides an application of the composite shielding material described in the first aspect of this application or the composite shielding material prepared by the method described in the second aspect of this application in aerospace, marine engineering, and corrosion protection and shielding of electronic equipment.
[0057] In some embodiments of this application, the method of application includes coating the composite shielding material onto the surface of the shielding material to be protected against corrosion, and curing it to obtain an anti-corrosion shielding coating.
[0058] In some embodiments of this application, the curing temperature is 180-200℃, such as 180℃, 185℃, 190℃, 196℃, 200℃, etc., and the curing time is 25-35min, such as 25min, 28min, 30min, 32min, 35min, etc.
[0059] In some embodiments of this application, the thickness of the anti-corrosion shielding coating is 40-60um, such as 40um, 43um, 45um, 48um, 50um, 53um, 55um, 60um, etc.
[0060] The technical solution of this application will be further described below with reference to specific embodiments.
[0061] Example 1
[0062] A method for preparing a composite shielding material includes the following steps:
[0063] (1) Preparation of graphene oxide with an oxygen content of 8.0 wt%.
[0064] Graphene oxide and ascorbic acid were mixed at a mass ratio of 2:1 and reduced at 50°C for 1 hour to obtain graphene oxide with an oxygen content of 8.0 wt%.
[0065] (2) Dissolve 8g of tridecafluorooctyltriethoxysilane in 50ml of a mixed solvent of ethanol and water (volume ratio of ethanol to water is 9:1), adjust the pH of the mixture to 4.5 with 0.5M hydrochloric acid solution, hydrolyze at 35℃ for 30min, add 25g of the above graphene oxide to the hydrolyzed tridecafluorooctyltriethoxysilane solution, and react at 70℃ for 8h to allow graphene oxide and tridecafluorooctyltriethoxysilane to be linked by Si-OC bonds. After the reaction is completed, centrifuge the reaction solution, wash the centrifuged solid, and vacuum dry to obtain modified graphene oxide.
[0066] (3) The above modified graphene oxide, FEVE type fluorocarbon resin and BYK163 dispersant were mixed at a mass ratio of 15:200:1. The mixture was ultrasonically treated at 400W for 30 minutes to obtain the anti-corrosion shielding material.
[0067] (4) The above anti-corrosion shielding material is coated on Q235 steel plate and cured at 180°C for 30 min to obtain an anti-corrosion shielding coating with a thickness of 50 μm.
[0068] Example 2
[0069] The only difference between the preparation method of the composite shielding material in Example 2 and that in Example 1 is that heptadecafluorodecyltrimethoxysilane is used instead of tridecafluorooctyltriethoxysilane in the preparation process of the composite shielding material in Example 2.
[0070] Example 3
[0071] The only difference between the preparation method of the composite shielding material in Example 3 and Example 1 is that the oxygen content of the graphene oxide used in the preparation process of the composite shielding material in Example 4 is 5 wt%.
[0072] The specific operating steps include:
[0073] (1) Preparation of graphene oxide with an oxygen content of 5 wt%.
[0074] Graphene oxide and ascorbic acid were mixed at a mass ratio of 2:1 and reduced at 50°C for 2 hours to obtain graphene oxide with an oxygen content of 5 wt%; the remaining operation steps were the same as in Example 1.
[0075] Example 4
[0076] The only difference between the preparation method of the composite shielding material in Example 4 and Example 1 is that the oxygen content of the graphene oxide used in the preparation process of the composite shielding material in Example 5 is 10 wt%.
[0077] The specific operating steps include:
[0078] (1) Preparation of graphene oxide with an oxygen content of 10 wt%.
[0079] Graphene oxide and ascorbic acid were mixed at a mass ratio of 2:1 and reduced at 50°C for 0.8 h to obtain graphene oxide with an oxygen content of 10 wt%; the remaining operation steps were the same as in Example 1.
[0080] Example 5
[0081] The only difference between the preparation method of the composite shielding material in Example 5 and that in Example 1 is that BYK-190 dispersant is used instead of BYK-163 dispersant in the preparation process of the composite shielding material in Example 6.
[0082] Example 6
[0083] The only difference between the preparation method of the composite shielding material described in Example 6 and Example 1 is that the amount of dispersant added during the preparation of the composite shielding material described in Example 8 is 0.2% of the weight of the fluorocarbon resin.
[0084] Example 7
[0085] The only difference between the preparation method of the composite shielding material in Example 7 and that in Example 1 is that the amount of dispersant added during the preparation of the composite shielding material in Example 9 is 0.8% of the weight of the fluorocarbon resin.
[0086] Example 8
[0087] The only difference between the preparation method of the composite shielding material described in Example 8 and Example 1 is that the amount of dispersant added during the preparation of the composite shielding material described in Example 10 is 1% of the weight of the fluorocarbon resin.
[0088] Comparative Example 1
[0089] The only difference between the preparation method of the composite shielding material described in Comparative Example 1 and Example 1 is that the oxygen content of the graphene oxide used in the preparation process of the composite shielding material described in Comparative Example 1 is 18.3 wt%.
[0090] Comparative Example 2
[0091] The only difference between the preparation method of the composite shielding material described in Comparative Example 2 and Example 1 is that the composite shielding material described in Comparative Example 2 uses virgin graphene, i.e., graphene oxide with an oxygen content of 2.1 wt%.
[0092] Comparative Example 3
[0093] The only difference between the preparation method of the composite shielding material described in Comparative Example 3 and Example 1 is that the graphene oxide was not modified during the preparation process of the composite shielding material described in Comparative Example 3.
[0094] The specific operating steps include:
[0095] (1) Preparation of graphene oxide with an oxygen content of 8.2 wt%.
[0096] Graphene oxide and ascorbic acid were mixed at a mass ratio of 2:1 and reduced at 50°C for 1 hour to obtain graphene oxide with an oxygen content of 8.2 wt%.
[0097] (2) The above-mentioned graphene oxide, FEVE type fluorocarbon resin and BYK163 dispersant were mixed at a mass ratio of 15:200:1. The mixture was ultrasonically treated at 400W for 30 minutes to obtain the anti-corrosion shielding material.
[0098] (3) The above anti-corrosion shielding material is coated on Q235 steel plate and cured at 180°C for 30 min to obtain an anti-corrosion shielding coating with a thickness of 50 μm.
[0099] Performance Study of Anti-corrosion Shielding Coatings Prepared from the Composite Shielding Materials Described in Examples 1-11 of this Application
[0100] Contact angle: Measured using a contact angle tester manufactured by Dataphysics, Germany, in accordance with standard ASTM D7334.
[0101] Salt spray test: The test was conducted using the German RSI salt spray corrosion chamber in accordance with the relevant requirements of GB / T1771.
[0102] Shielding effectiveness: The electromagnetic shielding performance of the coating was tested using the interference voltage method.
[0103] The results are shown in Table 1:
[0104] Table 1. Performance study results of the composite shielding material described in this application.
[0105] Contact angle / ° Salt spray test / h Electromagnetic shielding effectiveness / dB Example 1 138 1800 35 Example 2 142 1800 32 Example 3 137 1800 36 Example 4 133 1600 34 Example 5 130 1200 30 Example 6 132 1200 32 Example 7 135 1600 33 Example 8 134 1500 34 Comparative Example 1 102 400 12 Comparative Example 2 125 800 17 Comparative Example 3 130 700 18
[0106] As can be seen from Table 1, the composite shielding material described in this application has excellent hydrophobic and corrosion-resistant properties, and also has a good electromagnetic shielding effect.
[0107] Comparing Examples 1 and 3-4, it can be seen that the composite shielding material obtained when the oxygen content of graphene oxide is 5%-8% exhibits good hydrophobicity, corrosion resistance, and electromagnetic shielding effect. Excessive oxygen content in graphene oxide leads to poor conductivity and high water absorption, reducing the shielding and corrosion resistance of the coating; conversely, insufficient oxygen content limits the number of graftable groups, affecting the dispersion of graphene in the coating and resulting in performance similar to coatings without graphene oxide modification.
[0108] Comparing Example 1 and Example 5, it can be seen that the composite shielding material obtained by using BYK-163 dispersant has good hydrophobic properties, corrosion resistance, and electromagnetic shielding effect.
[0109] Comparing Examples 1 and 6-8, it can be seen that when the amount of dispersant added is 0.5%-0.8% of the weight of the fluorocarbon resin, the prepared composite shielding material has good hydrophobic properties, corrosion resistance, and electromagnetic shielding effect. Too much or too little dispersant will have negative effects: excessive dispersant will lead to decreased system stability, flocculation or sedimentation, and reduced performance, hindering coating curing, etc. Insufficient dispersant will cause filler precipitation.
[0110] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.
Claims
1. A composite shielding material, characterized in that, Including fluorocarbon resins and modified graphene oxide; The modified graphene oxide comprises graphene oxide and a silane coupling agent containing hydrophobic groups, wherein the graphene oxide and the silane coupling agent containing hydrophobic groups are connected by Si-OC bonds. The oxygen content of the graphene oxide is 5-10 wt%.
2. The composite shielding material according to claim 1, characterized in that, The mass ratio of the fluorocarbon resin to the modified graphene oxide is (9-20):1; And / or, the mass ratio of the modified graphene oxide to the silane coupling agent containing hydrophobic groups in the modified graphene oxide is (1-10):
1.
3. The composite shielding material according to claim 1, characterized in that, The silane coupling agents containing hydrophobic groups include tridecafluorooctyltriethoxysilane and / or heptadecafluorodecyltrimethoxysilane; And / or, the fluorocarbon resin includes FEVE type fluorocarbon resin.
4. The method for preparing the composite shielding material according to any one of claims 1-3, characterized in that, Includes the following steps: (1) Mix the silane coupling agent and solvent to obtain a mixture, and adjust the pH of the mixture to acidic for hydrolysis; (2) The hydrolyzed silane coupling agent mixture and graphene oxide were mixed and the two were grafted through Si-OC bonds to obtain modified graphene oxide. (3) The modified graphene oxide, fluorocarbon resin and dispersant are mixed to obtain the composite shielding material.
5. The method for preparing the composite shielding material according to claim 4, characterized in that, In step (1), the solvent includes one or more of water, methanol, and ethanol; And / or, in step (1), the pH of the mixture is adjusted using hydrochloric acid solution; and the pH value is adjusted to 4-5; And / or, in step (1), the hydrolysis temperature is 30-45℃ and the hydrolysis time is 20-40min.
6. The method for preparing the composite shielding material according to claim 4, characterized in that, In step (2), the mixing temperature is 60-80℃ and the mixing time is 6-12h.
7. The method for preparing the composite shielding material according to claim 4, characterized in that, In step (3), the dispersant includes BYK series dispersants; And / or, in step (3), the mixing includes ultrasonic mixing.
8. The method for preparing the composite shielding material according to claim 7, characterized in that, The BYK series dispersants include one or more of BYK-220S dispersant, BYK-110 dispersant, and BYK-163 dispersant; And / or, the amount of the dispersant added is 0.1%-1% of the weight of the fluorocarbon resin; And / or, the ultrasonic power of the ultrasonic mixing is 200-500W, and the ultrasonic mixing time is 30-60min.
9. The application of the composite shielding material according to any one of claims 1-3 or the composite shielding material obtained by the preparation method according to any one of claims 4-8 in aerospace, marine engineering, and corrosion protection and shielding of electronic equipment.
10. The application according to claim 9, characterized in that, The method of application includes coating the anti-corrosion shielding material onto the surface of the material to be protected against corrosion and curing it to obtain an anti-corrosion shielding coating. The curing temperature is 180-200℃, and the curing time is 25-35 minutes; The thickness of the anti-corrosion shielding coating is 40-60 μm.