Low-dielectric-constant hydrophobic anti-icing and deicing prepreg, preparation method and composite material component

Abstract

The invention belongs to the field of low-dielectric functional composite materials, and particularly relates to a low-dielectric-constant hydrophobic anti-icing prepreg, a preparation method and a composite material component. According to the prepreg, low-dielectric resin serves as a matrix, reinforced fibers and hydrophobic components in gradient distribution are compounded, the low-dielectric characteristic that the dielectric constant is smaller than or equal to 3.0 (10 GHz) is kept, the synergistic effect that a surface layer efficiently prevents and removes ice and an inner layer guarantees mechanical and dielectric properties is achieved through gradient distribution of the hydrophobic components, and the preparation method has the advantages that through distributed gum dipping and special-shaped compression roller regulation and control; the coating is suitable for high-frequency communication components which need excellent low dielectric properties and need anti-icing and deicing functions, and the problems that a traditional anti-icing and deicing coating is poor in compatibility with a low dielectric substrate and the dielectric properties are interfered are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of low dielectric functional composites, in particular to a low dielectric constant gradient hydrophobic anti-icing prepreg and its preparation method and application, especially suitable for components in high-frequency communication and outdoor equipment that require both low dielectric and anti-icing performance, and specifically relates to a low dielectric constant hydrophobic anti-icing prepreg, a preparation method and a composite component. BACKGROUND

[0002] In the fields of radar, 5G communication, etc., components need to have a low dielectric constant (≤3.0) to reduce signal transmission loss, and at the same time, outdoor use is prone to be affected by ice and snow adhesion; for example, radar cover icing will cause high electromagnetic wave reflectivity, and antenna cover snowing will attenuate signal strength, and the existing technology has two major contradictions: 1. Traditional anti-icing coatings mostly contain high dielectric fillers (such as metal oxides), which will significantly increase the dielectric constant of the component and interfere with signal transmission.

[0003] 2. The surface energy of low dielectric matrix (such as cyanate ester, PTFE modified resin) is low, and the adhesion with the hydrophobic coating is weak, and the coating is easy to fall off, and uniform addition of hydrophobic ingredients will damage the low dielectric structure of the matrix.

[0004] Therefore, the development of a prepreg with low dielectric constant, long-term anti-icing performance and excellent mechanical properties has become the key to solving the above contradictions. SUMMARY

[0005] The purpose of the present application is to solve the problem of large dielectric interference and poor adhesion of the existing low dielectric component anti-icing coating. The present application provides a low dielectric constant hydrophobic anti-icing prepreg, a preparation method and a composite component by matching the gradient distribution of hydrophobic ingredients and the low dielectric matrix, realizing the synergistic function of "surface anti-icing and inner layer dielectric preservation".

[0006] TECHNICAL SCHEME A low dielectric constant hydrophobic anti-icing prepreg is composed of reinforcing fibers and a low dielectric modified resin matrix with a dielectric constant less than 3.0, wherein the reinforcing fibers account for 45%~65%, and the low dielectric gradient modified resin matrix accounts for 35%~55%.

[0007] Further, the low dielectric modified resin matrix includes, by mass percentage: low dielectric matrix resin 65%~85%, hydrophobic component 12%~25%, gradient control agent 0.5%~3%, low dielectric curing agent 2%~6%, and antioxidant 0.5%~1%.

[0008] Further, the low dielectric matrix resin is selected from one of cyanate ester CE, polytetrafluoroethylene PTFE modified epoxy resin or bismaleimide-triazine resin BT resin.

[0009] Further, the hydrophobic component is a composite system of fluorine content ≥40% perfluoroalkyl ether F-POSS and hollow glass microspheres, wherein the mass ratio of perfluoroalkyl ether F-POSS to hollow glass microspheres is 1:2-3:1, and the micro-diameter of the hollow glass microspheres is 5-20 µm.

[0010] Further, the reinforcing fibers are selected from quartz fibers or ultra-high molecular weight polyethylene fibers, wherein the diameter of the ultra-high molecular weight polyethylene fibers is 10-15 µm.

[0011] Further, the gradient control agent is a fluorine-containing polyether silicone oil for controlling the enrichment of the hydrophobic component on the surface layer; and the low-dielectric curing agent is selected from 4,4'-diaminodiphenyl methane (DDM) modified cyanate ester or perfluorophenyl glycidyl ether.

[0012] A method for preparing a low dielectric constant hydrophobic anti-icing prepreg as described above, comprising the following steps: Preparation of the base material: mix 65%-85% low dielectric matrix resin, 12%-25% hydrophobic component, 0.5%-3% gradient control agent, 2%-6% low dielectric curing agent, and 0.5%-1% antioxidant, and stir at 1800-2200 r / min under vacuum at 70-90°C for 30-40 min to obtain a low dielectric base material; The reinforcing fibers pass through the base material pre-impregnation tank in sequence, and the attachment thickness of the base material on the surface of the fibers is controlled by a special-shaped compression roller; Remove the volatile components through a low-temperature drying channel, and roll up to obtain a low dielectric constant gradient hydrophobic anti-icing prepreg, wherein the low-temperature channel environment is 30-40°C for 8-12 min.

[0013] A composite material component prepared from the low dielectric constant hydrophobic anti-icing prepreg as described above, comprising: At least three layers of low dielectric constant gradient hydrophobic anti-icing prepreg are laid and cured to form a shape, wherein along the thickness direction from outside to inside, the hydrophobic component of each layer of low dielectric constant gradient hydrophobic anti-icing prepreg gradually decreases according to the mass gradient.

[0014] Further, the curing forming conditions are: temperature 150-180°C, pressure 0.8-1.5 MPa, and holding time 1.5-3 h.

[0015] Advantages: 1. Core design: low dielectric resin (cyanate ester, BT resin, etc.) is used as the matrix, low dielectric reinforcing fibers (quartz fibers, etc.) are compounded, and the hydrophobic component (F-POSS and hollow glass microspheres) is distributed along the thickness direction in a gradient manner - high content (20%-25%) on the surface layer to ensure hydrophobic anti-icing, low content (12%-15%) in the inner layer to avoid interference with dielectric properties, and the overall dielectric constant is controlled to ≤3.0.

[0016] 2. Key ingredient functions: F-POSS: Fluorine groups provide excellent hydrophobicity, cage structure avoids fluorine component aggregation, and its own dielectric constant ≤2.0, does not interfere with low dielectric matrix; Hollow glass microbeads: both enhance surface roughness to improve hydrophobic effect, and maintain overall low dielectric properties due to internal hollow structure (dielectric constant ≤2.0); Gradient control agent (fluorine-containing polyether silicone oil): use the compatibility of fluorine chain and F-POSS to guide the migration of hydrophobic components to the surface layer, and realize gradient distribution.

[0017] 3. Performance advantages Low dielectric stability: dielectric constant ≤3.0 at 10GHz, dielectric loss ≤0.005, meeting the needs of high frequency communication; Long-acting ice prevention: surface contact ≥145°, ice and snow adhesion reduced by more than 90%, performance decay ≤10% after 500 cycles of cold and hot cycles; Mechanical properties and compatibility: tensile strength ≥800MPa (carbon fiber reinforced), hydrophobic components have strong bonding force with low dielectric resin, and there is no risk of falling off. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. The drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.

[0019] Figure 1 A schematic view of a composite member prepared from the low dielectric constant hydrophobic ice prevention prepreg according to the embodiments of the present application. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0021] The features and illustrative embodiments of various aspects of the present application are described below in detail. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one of ordinary skill in the art that the present application can be practiced without some or all of these specific details. In other instances, well known structures and functions have not been described in detail in order to not unnecessarily obscure the concept of the present application. The detailed description of the embodiments below is merely intended to provide a better understanding of the present application. The present application is not limited to any particular setting or method as described below, but covers any modification, equivalent, and alternative of structure, method, device, etc. within the spirit of the present application. In the drawings and the following description, well-known structures and techniques have not been shown in order not to unnecessarily obscure the concept of the present application.

[0022] In the description of the present application, it should be noted that the directions or positional relationships belonging to "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are the directions or positional relationships described based on the drawings, and are only for the convenience of describing the present application and simplifying the description, and cannot be understood as a limitation on the present application. In addition, the ordinal numbers (for example, "first and second", etc.) are used to distinguish objects, and are not limited to the order, and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, "mounting", "connection", "connection" should be understood in a broad sense, which can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] It should be noted that, in the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other, and each embodiment can be mutually referred to and quoted. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0025] The present application will be further described in detail below in combination with the embodiments and the drawings, but the embodiments of the present application are not limited thereto.

[0026] The low dielectric constant hydrophobic ice-preventing pre-impregnated material provided by the present application is composed of reinforcing fibers and a low dielectric constant modified resin matrix with a dielectric constant less than 3.0, wherein the reinforcing fibers account for 45% to 65%, and the low dielectric gradient modified resin matrix accounts for 35% to 55%.

[0027] In one possible embodiment, the low dielectric constant modified resin matrix includes, in terms of mass percentage, low dielectric constant matrix resin 65% to 85%, hydrophobic component 12% to 25%, gradient control agent 0.5% to 3%, low dielectric constant curing agent 2% to 6%, and antioxidant 0.5% to 1%.

[0028] In one possible embodiment, the low dielectric matrix resin is selected from one of cyanate ester CE, polytetrafluoroethylene PTFE modified epoxy resin or bismaleimide-triazine resin BT resin. The dielectric constant thereof is ≤2.8 at 10 GHz.

[0029] In one possible embodiment, the hydrophobic component is a composite system of perfluoroalkyl ether F-POSS with a fluorine content ≥40% and hollow glass microbeads, wherein the mass ratio of perfluoroalkyl ether F-POSS to hollow glass microbeads is 1:2-3:1, and the micro-diameter of the hollow glass microbeads is 5-20 µm (dielectric constant ≤2.0).

[0030] In one possible embodiment, the reinforcing fiber is selected from quartz fiber (dielectric constant ≤3.2) or ultra-high molecular weight polyethylene fiber (dielectric constant ≤2.5), wherein the diameter of the ultra-high molecular weight polyethylene fiber is 10-15 µm.

[0031] In one possible embodiment, the gradient control agent is a fluorine-containing polyether silicone oil (viscosity 100-500 cSt, dielectric constant ≤2.2) for controlling the enrichment of the hydrophobic component on the surface layer; and the low dielectric curing agent is selected from 4,4'-diaminodiphenyl methane DDM modified cyanate ester or perfluorophenyl glycidyl ether, with a dielectric constant ≤2.5.

[0032] The surface water contact angle of the prepreg is ≥145°, and after 500 thermal and cold cycles from -50°C to 80°C, the surface water contact angle remains ≥135°, and the dielectric constant change rate is ≤5%; the tensile strength is ≥800 MPa (when reinforced by carbon fiber) or ≥350 MPa (when reinforced by quartz fiber).

[0033] A method for preparing the above-mentioned low dielectric constant hydrophobic deicing prepreg, comprising the following steps: Preparation of the base material: mix 65%-85% low dielectric matrix resin, 12%-25% hydrophobic component, 0.5%-3% gradient control agent, 2%-6% low dielectric curing agent, and 0.5%-1% antioxidant, and stir at 70-90°C under vacuum (vacuum degree ≤-0.09 MPa) at 1800-2200 r / min for 30-40 min to obtain a low dielectric base material; a planetary vacuum stirrer is used for stirring, and nitrogen is introduced during the stirring process to prevent oxidation of the resin; The reinforcing fiber is treated by plasma, and the plasma treatment uses a mixed gas of argon and carbon tetrachloride (volume ratio 3:1), and the surface contact angle of the reinforcing fiber is reduced to ≤30° after the treatment, thereby improving the wettability with the low dielectric resin; The reinforcing fiber successively passes through a base material pre-dipping tank (dipping speed 0.5-1.0 m / min), and a special-shaped compression roller is used to control the thickness of the base material attached to the surface of the fiber; The volatile components are removed through a low-temperature drying channel, and a low-dielectric constant gradient hydrophobic anti-icing prepreg is obtained by winding, wherein the low-temperature channel environment is 30-40℃, and the time is 8-12min.

[0034] As Figure 1 A composite component prepared from the above low-dielectric constant hydrophobic anti-icing prepreg, comprising: At least three layers of low-dielectric constant gradient hydrophobic anti-icing prepreg are laid and cured to form a shape, wherein the hydrophobic component of each layer of low-dielectric constant gradient hydrophobic anti-icing prepreg gradually decreases in mass from outside to inside along the thickness direction.

[0035] Further, the curing forming conditions are: temperature 150-180℃, pressure 0.8-1.5MPa, and holding time 1.5-3h.

[0036] The dielectric constant of the component is ≤3.0 at 10GHz, the dielectric loss is ≤0.008, and the ice and snow adhesion at -30℃ is reduced by more than 90% compared to ordinary low-dielectric components. After the component is placed in an environment of 85℃ and 85% relative humidity for 1000h, the dielectric constant change rate is ≤3%, the surface water contact angle remains ≥130°, and there is no delamination or cracking phenomenon. It is used to prepare 5G communication antenna covers, high-voltage transmission line insulation components, or wind turbine blades, etc. which require both low-dielectric properties and anti-icing function.

[0037] Example 1 (structure 1) 1. Raw material composition of low-dielectric constant hydrophobic anti-icing prepreg (mass parts): Reinforcing fibers: quartz fibers (55 parts); Low-dielectric matrix resin: cyanate ester resin (CE, dielectric constant 2.6, 30-35 parts); Hydrophobic component: F-POSS (fluorine content 42%) and hollow glass microspheres (10µm, dielectric constant 1.8) mixed in a ratio of 2:1 (7-12 parts); Gradient control agent: fluorine-containing polyether silicone oil (viscosity 300cSt, dielectric constant 2.1, 0.5 parts); Low-dielectric curing agent: DDM modified cyanate ester (dielectric constant 2.4, 2 parts); Antioxidant: 1010 (0.5 parts).

[0038] 2. Preparation steps: 30 parts of low-dielectric matrix resin, 12 parts of hydrophobic component, 0.5 parts of gradient regulator, 2 parts of low-dielectric curing agent, and 0.5 parts of antioxidant were mixed and stirred at 70℃ under vacuum at 2000 r / min (vacuum degree ≤ -0.09MPa) for 40 min to obtain low-dielectric modified resin matrix. The vacuum stirring was carried out using a planetary vacuum mixer, and nitrogen gas was introduced during the stirring process to prevent resin oxidation. Prepreg molding: Quartz fibers are treated with argon / carbon tetrafluoride plasma (400W, 4min), impregnated with a low-dielectric modified resin matrix, and prepreg 1 is obtained by controlling the pressure with a 0.05mm grooved roller. Prepreg 2 is obtained by mixing the low-dielectric matrix resin (32 parts), hydrophobic component (11 parts), gradient regulator (0.5 parts), low-dielectric curing agent (2 parts), and antioxidant with a grooved roller of reinforcing fibers. Prepreg 3 is obtained by mixing the low-dielectric matrix resin (34 parts), hydrophobic component (9 parts), gradient regulator (0.5 parts), low-dielectric curing agent (2 parts), and antioxidant with a grooved roller of reinforcing fibers. Prepreg 4 is obtained by mixing the low-dielectric matrix resin (36 parts), hydrophobic component (7 parts), gradient regulator (0.5 parts), low-dielectric curing agent (2 parts), and antioxidant with a grooved roller of reinforcing fibers. Composite structural component 1 was prepared by hot pressing and curing.

[0039] Example 2 (Structural Component 2) 1. Raw material composition (parts by weight): Reinforcing fiber: Polyimide fiber (50 parts); Low dielectric matrix resin: BT resin (dielectric constant 2.7, 36-42 parts); Hydrophobic component: F-POSS (fluorine content 42%) and hollow glass microspheres (5µm, dielectric constant 1.8) are mixed in a 2:1 ratio (5-11 parts). Gradient regulator: Fluorinated polyether silicone oil (viscosity 200 cSt, 0.8 parts); Low dielectric curing agent: DDM modified cyanate ester (dielectric constant 2.3, 2 parts); Antioxidant: 168 (0.2 parts).

[0040] 2. Preparation steps: 36 parts of low-dielectric matrix resin, 11 parts of hydrophobic component, 0.8 parts of gradient regulator, 2 parts of low-dielectric curing agent, and 0.2 parts of antioxidant were mixed and stirred at 80℃ under vacuum at 2000 r / min (vacuum degree ≤ -0.09MPa) for 30 min to obtain low-dielectric modified resin matrix. The vacuum stirring was carried out using a planetary vacuum mixer, and nitrogen gas was introduced during the stirring process to prevent resin oxidation. Prepreg molding: Quartz fibers are treated with argon / carbon tetrafluoride plasma (400W, 4min), impregnated with a low-dielectric modified resin matrix, and prepreg 1 is obtained by controlling the pressure with a 0.05mm grooved roller. Prepreg 2 is obtained by mixing the low-dielectric matrix resin (38 parts), hydrophobic component (9 parts), gradient regulator (0.8 parts), low-dielectric curing agent (2 parts), and antioxidant (0.2 parts) with a grooved roller for reinforcing fibers. Prepreg 3 is obtained by mixing the low-dielectric matrix resin (40 parts), hydrophobic component (7 parts), gradient regulator (0.8 parts), low-dielectric curing agent (2 parts), and antioxidant (0.2 parts) with a grooved roller for reinforcing fibers. Prepreg 4 is obtained by mixing the low-dielectric matrix resin (42 parts), hydrophobic component (5 parts), gradient regulator (0.8 parts), low-dielectric curing agent (2 parts), and antioxidant (0.2 parts) with a grooved roller for reinforcing fibers. Composite structural component 2 was prepared by hot pressing and curing.

[0041] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A low dielectric constant hydrophobic anti-icing prepreg, characterized in that, It is composed of reinforcing fibers and a low-dielectric modified resin matrix with a dielectric constant of less than 3.0, wherein the reinforcing fibers account for 45% to 65% and the low-dielectric modified resin matrix accounts for 35% to 55%.

2. The low dielectric constant hydrophobic anti-icing prepreg according to claim 1, characterized in that, The low-dielectric modified resin matrix comprises, by weight percentage: 65%~85% low-dielectric matrix resin, 12%~25% hydrophobic component, 0.5%~3% gradient regulator, 2%~6% low-dielectric curing agent, and 0.5%~1% antioxidant.

3. The low dielectric constant hydrophobic anti-icing prepreg according to claim 2, characterized in that, The low dielectric matrix resin is selected from one of the following: cyanate ester (CE), polytetrafluoroethylene (PTFE) modified epoxy resin, or bismaleimide-triazine resin (BT resin).

4. The low dielectric constant hydrophobic anti-icing prepreg according to claim 3, characterized in that, The hydrophobic component is a composite system of perfluoroalkyl ether F-POSS with a fluorine content ≥40% and hollow glass microspheres, wherein the mass ratio of perfluoroalkyl ether F-POSS to hollow glass microspheres is 1:2~3:1, and the micro-diameter of hollow glass microspheres is 5~20µm.

5. The low dielectric constant hydrophobic anti-icing prepreg according to claim 4, characterized in that, The reinforcing fiber is selected from quartz fiber or ultra-high molecular weight polyethylene fiber, wherein the ultra-high molecular weight polyethylene fiber has a diameter of 10~15µm.

6. The low dielectric constant hydrophobic anti-icing prepreg according to claim 5, characterized in that, The gradient regulator is a fluorinated polyether silicone oil, used to regulate the enrichment of hydrophobic components on the surface; the low dielectric curing agent is selected from 4,4'-diaminodiphenylmethane DDM modified cyanate ester or perfluorophenyl glycidyl ether.

7. A method for preparing a low dielectric constant hydrophobic anti-icing prepreg as described in any one of claims 1-6, characterized in that, Includes the following steps: Preparation of base material: Mix 65%~85% low dielectric matrix resin, 12%~25% hydrophobic component, 0.5%~3% gradient regulator, 2%~6% low dielectric curing agent, and 0.5%~1% antioxidant, and stir under vacuum at 1800~2200 r / min for 30~40 min at 70~90℃ to obtain low dielectric base material; The reinforcing fibers pass through the base material prepreg tank in sequence, and the adhesion thickness of the base material on the fiber surface is controlled by the shaped pressure roller; The volatiles are removed by a low-temperature drying channel, and the material is then wound up to obtain a low dielectric constant gradient hydrophobic anti-icing prepreg. The low-temperature channel environment is 30~40℃ for 8~12 minutes.

8. A composite material component prepared from the low dielectric constant hydrophobic anti-icing prepreg described in claim 7, characterized in that, include: At least three layers of low dielectric constant gradient hydrophobic anti-icing prepreg are laid and cured, wherein the hydrophobic component of each layer of low dielectric constant gradient hydrophobic anti-icing prepreg gradually decreases according to the mass gradient from the outside to the inside along the thickness direction.

9. The composite material component according to claim 8, characterized in that, The curing conditions are: temperature 150~180℃, pressure 0.8~1.5MPa, and holding time 1.5~3h.

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