A flexible multifunctional material and a method for preparing the same

Abstract

The application provides a flexible multifunctional material and a preparation method thereof, and relates to the technical field of flexible materials.The flexible multifunctional material comprises a functional layer and a pressure-sensitive layer, the pressure-sensitive layer comprises a plurality of units with a negative Poisson's ratio effect arranged in an array, the top end of the unit is connected with the functional layer, the height of the units arranged transversely is the same, and the height of adjacent units arranged longitudinally is different; and the flexible multifunctional material is obtained by integrally forming the flexible material.The flexible multifunctional material provided by the application has the functions of heat resistance, wave absorption and excellent covering, and can be prepared industrially.

Description

Technical Field

[0001] This invention relates to the field of flexible materials technology, and in particular to a flexible multifunctional material and its preparation method. Background Technology

[0002] Negative Poisson's ratio materials and structures possess unique mechanical properties, exhibiting lateral contraction (expansion) under uniaxial pressure (tension). They demonstrate advantages over traditional materials in shear strength, fracture resistance, energy absorption, and indentation resistance. Therefore, negative Poisson's ratio materials have broad application prospects in medical devices, flexible sensors, protective equipment, aerospace, marine engineering, and defense engineering. Compared to flexible materials such as hydrogels and foams, negative Poisson's ratio materials exhibit superior mechanical and impact resistance properties, and are easier to fit tightly onto non-developable surfaces, resulting in better conformability. However, the application and widespread adoption of negative Poisson's ratio materials still face some challenges.

[0003] The main problems currently facing negative Poisson's ratio materials are high manufacturing costs and difficulty in industrialization. Except for fabric forms, most negative Poisson's ratio materials require 3D printing, which is time-consuming, costly, and size-limited. While fabric-based negative Poisson's ratio structures offer excellent conformability, their function is limited, requiring collaboration with other functional materials to achieve heat protection, electromagnetic induction, and infrared stealth capabilities. Furthermore, differences in material composition between the fabric and functional materials can lead to wrinkles and cracks. Therefore, it is necessary to propose a flexible, multifunctional material that combines heat protection, wave absorption, and excellent conformability, along with its preparation method. Summary of the Invention

[0004] This invention provides a flexible multifunctional material and its preparation method. The provided flexible multifunctional material has heat protection, wave absorption and excellent conformability, and can be industrially prepared.

[0005] In a first aspect, the present invention provides a flexible multifunctional material, comprising a functional layer and a pressure-sensitive layer, wherein the pressure-sensitive layer comprises an array of multiple units having a negative Poisson's ratio effect, the top of the units being connected to the functional layer, the units arranged laterally having the same height, and the adjacent units arranged longitudinally having different heights; the flexible multifunctional material is integrally formed from a flexible material.

[0006] Preferably, the structure of the unit includes a concave corner structure, a chiral structure, and a rotational rigid body structure.

[0007] Preferably, the height ratio of the functional layer to the pressure-sensitive layer is (0.5-5):(0.3-10).

[0008] Preferably, the pressure-sensitive layer includes an array of first units and second units; wherein the height of the first unit is higher than the height of the second unit; and the height of the pressure-sensitive layer is the same as the height of the first unit.

[0009] In the longitudinal arrangement direction, the first unit is adjacent to the second unit.

[0010] Preferably, in the lateral arrangement direction, the ratio of the spacing between adjacent units to the width of the first unit is (0.1 to 1):1.

[0011] Preferably, the ratio of the length of the second unit to the height of the first unit is (1-300):1.

[0012] Preferably, the ratio of the height of the first unit to the height of the second unit is 1:(0.5 to 0.8).

[0013] Preferably, the bottom end of the first unit is also provided with an antenna, which is at least one of L-shaped, ⊥-shaped, and ┛-shaped.

[0014] Preferably, the flexible material is at least one of silicone rubber, natural rubber, polyurethane, and polyacrylate elastomer.

[0015] In a second aspect, the present invention provides a method for preparing the flexible multifunctional material described in the first aspect above, the method comprising:

[0016] A flexible material is extruded through a die of a screw extruder to obtain a preformed material; wherein, the cross-section of the die is designed with multiple continuously arranged units with a negative Poisson's ratio effect; the preformed material includes a functional layer and several rows of negative Poisson's ratio layers comprising multiple continuously arranged units.

[0017] After cutting the negative Poisson's ratio layer of the preformed material along the extrusion direction, the negative Poisson's ratio layer includes multiple units arranged in an array, thus obtaining the flexible multifunctional material; wherein, the heights of adjacent units arranged along the extrusion direction are different, and the heights of adjacent units arranged perpendicular to the extrusion direction are all the same.

[0018] Preferably, the flexible material is silicone rubber; the silicone rubber comprises the following components in parts by weight: 100 parts raw rubber, 35-40 parts silica, 1.5 parts zinc stearate, 5-8 parts structure control agent, 1-2 parts vinyl silicone oil, 1 part vulcanizing agent, and 0.5 parts additives.

[0019] Preferably, the bottom end of a unit with the same height as the unit on the template is cut to give the unit antennae.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects:

[0021] The flexible multifunctional material provided by this invention includes a functional layer and a pressure-sensitive layer integrally fabricated from flexible materials. The pressure-sensitive layer comprises multiple units with a negative Poisson's ratio effect arranged in an array. The top of each unit is connected to the functional layer. In the transverse direction of the array, the height of the units is the same; however, the heights of adjacent units in the longitudinal direction are different. Thus, this flexible multifunctional material, while utilizing the excellent mechanical and impact resistance properties of the units, can achieve close bonding on non-developable curved surfaces, exhibiting excellent conformability. Furthermore, the varying heights of the units further enhance the conformability of the flexible multifunctional material. Simultaneously, the functional layer and the pressure-sensitive layer with units are connected and integrally formed, avoiding problems such as wrinkles and cracks caused by material differences, thereby improving the mechanical properties of the flexible multifunctional material. In addition, the functional layer can also achieve functions such as heat protection, wave absorption, and infrared stealth.

[0022] In this invention, flexible multifunctional materials are integrally molded through co-extrusion. On the one hand, this enables the large-area manufacturing of materials with a negative Poisson's ratio structure to meet the needs of skin manufacturing for large components and achieve industrialized manufacturing. On the other hand, since the pressure-sensitive layer and the functional layer are integrated, the introduction of functional layers such as wave absorption, stealth, or heat protection will not be affected by the conformal properties. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic cross-sectional view of a flexible multifunctional material provided in an embodiment of the present invention;

[0025] Figure 2 yes Figure 1 The diagram shows a planar structure of a flexible multifunctional material.

[0026] Figure 3 This is a schematic cross-sectional view of another flexible multifunctional material provided in an embodiment of the present invention;

[0027] Figure 4 yes Figure 1 A schematic diagram of the planar structure of another flexible multifunctional material is shown;

[0028] Figure 5 This is a cross-sectional structural schematic diagram of another flexible multifunctional material provided in an embodiment of the present invention;

[0029] Figure 6 This is a cross-sectional structural schematic diagram of another flexible multifunctional material provided in an embodiment of the present invention;

[0030] Reference numerals: 10-functional layer; 20-pressure-sensitive layer; 200-unit; 201-first unit; 202-second unit; 2011-antennae. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] This invention provides a flexible multifunctional material, such as... Figure 1 and Figure 2 As shown, it includes: a functional layer 10 and a pressure-sensitive layer 20. The pressure-sensitive layer 20 includes multiple units 200 with negative Poisson's ratio effect arranged in an array. The top of the unit 200 is connected to the functional layer 10. The horizontally arranged units 200 have the same height, while the vertically arranged adjacent units 200 have different heights. The flexible multifunctional material is integrally formed from a flexible material.

[0033] In this invention, the flexible multifunctional material includes a functional layer and a pressure-sensitive layer integrally fabricated from flexible materials. The pressure-sensitive layer comprises multiple units arranged in an array, with the top of each unit connected to the functional layer. In the transverse direction of this array, the units have the same height; however, adjacent units in the longitudinal direction have different heights. Thus, this flexible multifunctional material, while leveraging the excellent mechanical and impact resistance of the units, can achieve a tight fit on non-developable curved surfaces, exhibiting excellent conformability. Furthermore, the varying heights of the units further enhance the conformability of the flexible multifunctional material. Simultaneously, the functional layer and the pressure-sensitive layer with units are connected and integrally formed, avoiding problems such as wrinkles and cracks caused by material differences, thereby improving the mechanical properties of the flexible multifunctional material. In addition, the functional layer can also achieve functions such as heat protection, wave absorption, and infrared stealth.

[0034] It should be noted that the terms "horizontal" and "vertical" do not constitute a specific limitation on the flexible multifunctional material; they are merely used to distinguish the arrangement direction. In specific embodiments, the vertically arranged units may all have the same height, while adjacent units arranged laterally may have different heights. The unit exhibiting the negative Poisson's ratio effect can be a unit containing a negative Poisson's ratio structure or a unit containing a quasi-negative Poisson's ratio structure.

[0035] Specifically, in practical applications, the flexible multifunctional material adheres to the complex curved surfaces of the device to be bonded. Because the bottom layer is a negative Poisson's ratio material, the bonding process can sensitively detect changes in the bonding surface and deform accordingly. After bonding, the characteristics of the internal curved surface essentially match those of the external functional layer. Furthermore, since the functional layer is flat, its bonding does not alter the contour and curvature of the device to be bonded. The surface of the functional layer is also smooth and wrinkle-free after bonding. Additionally, the flexible multifunctional material can be bonded to the surface of devices with varying curvatures through stretching or compression, exhibiting a negative Poisson's ratio bonding effect in both the stretching and compression directions.

[0036] According to some preferred embodiments, a plurality of units 200 in the pressure-sensitive layer 20 are arranged in a gradient.

[0037] Specifically, for devices with complex curved surfaces to be bonded, the curvature of the surface varies in different locations. Therefore, by flexibly designing the density of the elements (i.e., the spacing between adjacent elements) at different curvatures, they can be arranged in a gradient (e.g., such as...). Figure 1 As shown in the figure, it enables flexible multifunctional materials to adapt to changes in the curvature of the constructed surface, and can better utilize the performance of the negative Poisson's ratio structure in the pressure-sensitive layer.

[0038] According to some preferred embodiments, the structure of the unit includes a concave corner structure, a chiral structure, and a rotational rigid body structure.

[0039] Specifically, the preferred structure of the cell is a cellular cell with negative Poisson bit properties.

[0040] According to some preferred embodiments, the height ratio of the functional layer to the pressure-sensitive layer is (0.5~5):

[0041] (0.3~10) (For example, it can be 0.5:0.3, 1:1, 0.5:2, 0.5:5, 0.5:10, 1:0.3, 1:2, 1:5, 1:10, 2:0.3, 2:1, 2:5, 2:15, 5:0.3, 5:1 or 5:9).

[0042] Specifically, the thickness of the functional layer and the pressure-sensitive layer can be designed according to the actual service conditions.

[0043] According to some preferred embodiments, the height ratio of the functional layer to the pressure-sensitive layer is 1:(0.3 to 10) (for example, it can be 1:0.3, 1:0.5, 1:0.8, 1:1, 1:1.5, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10).

[0044] In this embodiment of the invention, the height ratio of the functional layer to the pressure-sensitive layer is 1:(0.3~10), which can avoid the functional layer being too thick, resulting in a large equivalent modulus and a low transfer efficiency from the pressure-sensitive layer to the functional layer. At the same time, it can further reduce the thickness of the flexible multifunctional composite material.

[0045] According to some preferred embodiments, such as Figure 3 and Figure 4 As shown, the pressure-sensitive layer 20 includes an array of first units 201 and second units 202; wherein, the height of the first unit 201 is higher than the height of the second unit 202, and both the first unit 201 and the second unit 202 contain a negative Poisson's ratio structure; the height of the pressure-sensitive layer 20 is the same as the height of the first unit 201.

[0046] In the vertical arrangement direction, the first unit 201 and the second unit 202 are adjacent.

[0047] In this embodiment of the invention, in the longitudinal arrangement direction, the first unit and the second unit with different heights are adjacent to each other, so that the unit can exert its excellent conforming performance on complex curved surfaces.

[0048] According to some preferred embodiments, both the first unit and the second unit are complete negative Poisson's ratio structural units.

[0049] In this embodiment of the invention, the units of the pressure-sensitive layer are all complete negative Poisson's ratio structural units. Thus, each unit is a complete negative Poisson's ratio structural unit, and each negative Poisson's ratio structural unit can fully exert its function, so that the flexible multifunctional material has a negative Poisson's ratio bonding effect in both the tensile and compressive directions.

[0050] According to some preferred embodiments, such as Figure 4 As shown, in the horizontal arrangement direction, the ratio of the spacing D1 between adjacent units to the width D2 of the first unit is (0.1 to 1):1 (for example, it can be 0.1:1, 0.15:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1 or 1:1).

[0051] In this embodiment of the invention, to make the flexible multifunctional material fit the curved surface of the device better, the ratio of the spacing between adjacent units to the width of the first unit is limited to (0.1~1):1. This allows the units with the negative Poisson's ratio effect to exhibit excellent conformability at any curvature. If the spacing is too large, it will reduce the conformability of the flexible multifunctional material and even affect its mechanical properties. It should be noted that the width of the first unit is the spacing of the widest part of the negative Poisson's ratio structure corresponding to the first unit.

[0052] According to some preferred embodiments, such as Figure 3 and Figure 4 As shown, the ratio of the length L of the second unit to the height H1 of the first unit is (1 to 300):1 (for example, it can be 1:1, 2:1, 5:1, 10:1, 15:1, 20:1, 30:1, 50:1, 100:1, 120:1, 150:1, 200:1, 250:1, 280:1 or 300:1).

[0053] It should be noted that the ratio of the length of the second unit to the height of the first unit is designed specifically according to the actual service conditions.

[0054] According to some preferred embodiments, such as Figure 3 As shown, the ratio of the height H1 of the first unit to the height H2 of the second unit is 1:(0.5 to 0.8) (for example, it can be 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75 or 1:0.8).

[0055] In this embodiment of the invention, the ratio of the height of the first unit to the height of the second unit is limited to 1:(0.5 to 0.8). This avoids the problems of poor flexibility and poor conformability of the flexible multifunctional material when the height difference between the two units is too low, and also avoids the problems of poor mechanical properties of the flexible multifunctional material when the height difference between the two units is too high.

[0056] According to some preferred embodiments, the bottom end of the first unit is also provided with antennae, which are at least one of L-shaped, ⊥-shaped, and ┛-shaped.

[0057] In this embodiment of the invention, the bottom of the first unit is in direct contact with the device to be bonded, and the antennae are located at the bottom of the first unit, which can further increase the contact area between the first unit and the device to be bonded, making the two bond more firmly.

[0058] According to some preferred embodiments, the flexible material is at least one of silicone rubber, natural rubber, polyurethane, and polyacrylate elastomer.

[0059] It should be noted that "at least one" means any one or more of them mixed in any proportion. The flexible material is preferably a material resistant to temperatures above 200°C.

[0060] The present invention also provides a method for preparing the above-mentioned flexible multifunctional material, the method comprising:

[0061] Flexible material is extruded through a die of a screw extruder to obtain a preformed material; wherein, the cross-section of the die is designed with multiple continuously arranged units with a negative Poisson's ratio effect; the preformed material includes a functional layer and several rows of negative Poisson's ratio layers comprising multiple continuously arranged units;

[0062] After cutting the negative Poisson's ratio layer of the preformed material along the extrusion direction, the negative Poisson's ratio layer includes multiple units arranged in an array, resulting in a flexible multifunctional material; wherein, the heights of adjacent units arranged along the extrusion direction are different, while the heights of units arranged perpendicular to the extrusion direction are all the same.

[0063] It should be noted that the negative Poisson's ratio layer consists of N rows, and each row is composed of multiple consecutively arranged units.

[0064] In this invention, flexible multifunctional materials are integrally formed by co-extrusion. Compared with 3D printing to prepare materials with negative Poisson's ratio structures, on the one hand, it can realize the large-area manufacturing of materials with negative Poisson's ratio structures to meet the skin manufacturing of large components, realize industrialized manufacturing, and reduce manufacturing costs; on the other hand, since the pressure-sensitive layer and the functional layer are integrated, the introduction of functional layers such as wave absorption, stealth or heat protection will not be affected by the conformal performance.

[0065] It should be noted that the horizontally arranged units mentioned above all have the same height, which essentially means that the units arranged perpendicular to the extrusion direction all have the same height; the vertically arranged adjacent units have different heights, which essentially means that the adjacent units arranged along or parallel to the extrusion direction have different heights. When the above template is installed at the front end of the extrusion head of the screw extruder, the flexible material passes through the screw extruder and the template, thus producing a long strip-shaped (cubic or cubic) product with a negative Poisson's ratio structure. The template, also known as the extrusion die or die, is a metal template made of stainless steel, aluminum alloy, or titanium alloy, etc. The cross-section of this metal template can be determined according to specific requirements and the intended use of the material and product.

[0066] More specifically, such as Figure 3 As shown, after the negative Poisson's ratio layer of the preform material is ordered cut along the extrusion direction, a first unit with the same height as the negative Poisson's ratio layer and a second unit with a lower height than the first unit are obtained. Moreover, in the direction parallel to the extrusion direction, the first unit and the second unit are adjacent to each other, forming an orderly contact surface with concave and convex surfaces. The unit with the negative Poisson's ratio effect can be a unit containing a negative Poisson's ratio structure or a unit containing a negative Poisson's ratio-like structure. After cutting, the negative Poisson's ratio structure or the negative Poisson's ratio-like structure in the unit may be partially destroyed, but since the unit still contains most of the complete negative Poisson's ratio structure or the negative Poisson's ratio-like structure, the first unit and the second unit after cutting still have the negative Poisson's ratio effect.

[0067] It should be noted that the cutting spacing can be equal spacing, ordered spacing designed according to gradients, or specific interval cutting designed according to the curvature of the surface.

[0068] More specifically, equidistant cutting includes the following two methods:

[0069] In the first case, both the first and second units after cutting are composed of several complete negative Poisson's ratio structural units. That is, the negative Poisson's ratio structures that make up the first and second units are the same, only the number of negative Poisson's ratio structural units that make up the first unit is different from the number of negative Poisson's ratio structural units that make up the second unit. In this case, the spacing during cutting is an integer multiple of the width of the negative Poisson's ratio structural unit, and the depth during cutting is an integer multiple of the height of the negative Poisson's ratio structural unit.

[0070] The second type involves both the first and second units after cutting being composed of several complete negative Poisson's ratio structural units, but the negative Poisson's ratio structural units composing the first unit are different from those composing the second unit; in this case, the spacing and depth of the cut are determined by the negative Poisson's ratio structural units composing the second unit. For example... Figure 5 As shown, the negative Poisson's ratio structural elements of the first and second units are different.

[0071] According to some preferred embodiments, the flexible material is silicone rubber; the silicone rubber comprises the following components in parts by weight: 100 parts raw rubber, 35-40 parts silica, 1.5 parts zinc stearate, 5-8 parts structure control agent, 1-2 parts vinyl silicone oil, 1 part vulcanizing agent, and 0.5 parts additives.

[0072] According to some preferred embodiments, the bottom end of a unit that is the same height as the unit on the template is cut off, so that the unit has antennae.

[0073] More specifically, such as Figure 6 As shown, an L-shaped, ⊥-shaped, or ┛-shaped antennae 2011 are obtained by cutting at the bottom of the first unit, which is the same height as the pressure-sensitive layer. The cutting dimensions of the antennae are designed according to specific application requirements.

[0074] It should be noted that the functional layer is designed to have certain functions such as wave absorption, sweat emission, and infrared stealth, according to application requirements.

[0075] To more clearly illustrate the technical solution and advantages of the present invention, the following detailed description of a method for preparing a flexible multifunctional material is provided through examples.

[0076] Example

[0077] (1) Mix the following components in parts by mass to obtain a compound: 100 parts raw rubber, 40 parts silica, 1.5 parts zinc stearate, 5 parts structure control agent (dimethyl hydroxy silicone oil), 2 parts vinyl silicone oil, 1 part vulcanizing agent (2,4-dichlorobenzoyl peroxide), and 0.5 parts additive (iron oxide).

[0078] (2) The compound is extruded through a twin-screw extruder to a pre-designed template at an extrusion temperature of 50°C. The extruded material is then subjected to hot air vulcanization (380°C for 30 seconds). After cooling to room temperature, a preformed material is obtained. This preformed material includes a functional layer and several rows of negative Poisson's ratio layers composed of multiple continuously arranged units. The extrusion direction is the Y direction (i.e.,...). Figure 4 (in the vertical direction);

[0079] (3) The continuously arranged units are cut at equal intervals along the YZ direction by mechanical cutting, so that the negative Poisson's ratio layer is an array of first unit 201 and second unit 202 arranged in an orderly manner, as shown in the figure. Figure 3 and Figure 4 The flexible multifunctional material shown includes an integrally formed functional layer 10 and an array of pressure-sensitive layers 20.

[0080] It should be noted that, Figure 4 The plane shown is the XY plane, where the horizontal direction is the X direction and the vertical direction is the Y direction; in the horizontal arrangement direction, the spacing D1 between adjacent units is set by the extrusion molding process.

[0081] The accompanying drawings are provided for illustrative purposes only, and the proportions, dimensions, and quantities of the parts in the drawings may not be consistent with the actual product.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flexible multifunctional material, characterized in that, The flexible multifunctional material includes a functional layer and a pressure-sensitive layer. The pressure-sensitive layer includes multiple units with a negative Poisson's ratio effect arranged in an array. The top of each unit is connected to the functional layer. The units arranged laterally all have the same height, while the adjacent units arranged vertically have different heights. The flexible multifunctional material is integrally formed from a flexible material. The structure of the unit includes a concave corner structure, a chiral structure, and a rotational rigid body structure; The height ratio of the functional layer to the pressure-sensitive layer is (0.5~5):(0.3~10). The pressure-sensitive layer includes an array of first and second units; wherein the height of the first unit is higher than the height of the second unit; and the height of the pressure-sensitive layer is the same as the height of the first unit. In the longitudinal arrangement direction, the first unit and the second unit are adjacent; In the horizontal arrangement direction, the ratio of the spacing between adjacent units to the width of the first unit is (0.1~1):1; The ratio of the length of the second unit to the height of the first unit is (1~300):1; The ratio of the height of the first unit to the height of the second unit is 1:(0.5~0.8).

2. The flexible multifunctional material according to claim 1, characterized in that: The bottom of the first unit is also provided with antennae, which are at least one of L-shaped, ⊥-shaped, and ┛-shaped.

3. The flexible multifunctional material according to claim 1 or 2, characterized in that: The flexible material is at least one of silicone rubber, natural rubber, polyurethane, and polyacrylate elastomer.

4. A method for preparing a flexible multifunctional material according to any one of claims 1 to 3, characterized in that, The preparation method includes: A flexible material is extruded through a die of a screw extruder to obtain a preformed material; wherein, the cross-section of the die is designed with multiple continuously arranged units with a negative Poisson's ratio effect; the preformed material includes a functional layer and several rows of negative Poisson's ratio layers comprising multiple continuously arranged units. After cutting the negative Poisson's ratio layer of the preformed material along the extrusion direction, the negative Poisson's ratio layer includes multiple units arranged in an array, thus obtaining the flexible multifunctional material; wherein, the heights of adjacent units arranged along the extrusion direction are different, and the heights of adjacent units arranged perpendicular to the extrusion direction are all the same.

5. The preparation method according to claim 4, characterized in that: The flexible material is silicone rubber; the silicone rubber comprises the following components in parts by weight: 100 parts raw rubber, 35-40 parts silica, 1.5 parts zinc stearate, 5-8 parts structure control agent, 1-2 parts vinyl silicone oil, 1 part vulcanizing agent, and 0.5 parts additives.

6. The preparation method according to claim 4, characterized in that: Cut the bottom of the unit that is the same height as the unit on the template to give the unit antennae.

Images