An integrated flexible artificial muscle fiber and a method for manufacturing the same

Abstract

The application discloses an integrated flexible artificial muscle fiber and a preparation method thereof, and belongs to the field of artificial muscle. The application utilizes silica gel with a Shore hardness of 30A to prepare an integrated flexible artificial muscle with a shrinkage rate of 20%, a single artificial muscle can bear a tensile force of 200N, can provide a driving force of 20N, and can realize response within a frequency of 50Hz. The application optimizes the vulcanization step in the preparation method, carries out secondary vulcanization, carries out partial vulcanization for the first time and fixed vulcanization for the second time, successfully constructs an integrated artificial muscle with a close combination of an inner silica gel tube, a braided layer and an outer silica gel tube, and the integrated artificial muscle will not break even if used for a long time, and the cycle life can reach more than 1.1 million to 5.2 million times. Even under the condition of load, the cycle life can still reach 110,000 to 970,000 times.

Description

Technical Field

[0001] This invention relates to an integral flexible artificial muscle fiber and its preparation method, belonging to the field of artificial muscles. Background Technology

[0002] Artificial muscles are artificial drive systems developed by mimicking the structure and function of biological muscles. Their core goals are to achieve flexibility, high power density, and fast response, and they can be applied to medical health, service robots, and industrial manufacturing.

[0003] Currently available artificial muscles mainly consist of elastic tubing and a braided mesh that restricts the deformation of the elastic tubing. When inflated with air, the internal elastic tubing expands radially and elongates axially. However, due to the constraint of the outer high-strength fiber braided mesh, the internal elastic tubing expands radially but contracts axially. The repeated inflation and deflation of these artificial muscles generates friction, resulting in poor durability. For example, patent applications CN208431222U and CN106037991A disclose typical artificial muscles of this type. Because the elastic inner tube and the fiber braided mesh are two independent contact surfaces, relative sliding and high-frequency friction inevitably occur between them during repeated inflation and deflation. This friction continuously wears down the outer wall of the inner tube, causing silicone aging, debris formation, and ultimately, the inner tube ruptures due to fatigue or wear, severely limiting its service life and stability under long-term, high-intensity tasks.

[0004] Typically, commercially available artificial muscles have relatively large internal cavities, resulting in longer inflation and deflation times. This leads to longer response times during operation, making them unsuitable for high-frequency environments. Currently, some products use silicone with a Shore hardness higher than 40A to ensure a firm "lock" in the woven fibers after molding. This directly results in excessive rigidity and insufficient flexibility in the final artificial muscle, significantly reducing its traction and biomimetic compliance. Even with one-piece molding, the physical bonding between the silicone matrix and the smooth chemical fiber woven layer remains limited. Under internal high pressure, stress concentrates at the interface between the silicone and the woven layer. Especially under complex conditions such as bending or torsion, this weak interface is prone to micro-delamination, which rapidly expands into irreversible delamination and tearing, leading to failure.

[0005] In summary, existing technologies, whether employing a split structure or preliminary attempts at integration, have failed to effectively solve the three core technical challenges of "durability (friction / delamination)," "high-frequency response (large volume / high stiffness)," and "industrial production."

[0006] Therefore, there is an urgent need in this field to develop a novel technical solution that can eliminate the risks of interlayer friction and delamination from the structural and material perspectives, while also taking into account high flexibility and low driving gas volume, and whose preparation process is simple and reliable, enabling low-cost large-scale production. Summary of the Invention

[0007] [Technical Issues] Whether using a split structure or making preliminary attempts at integrated fabrication of muscle fibers, neither has effectively solved the three core technical challenges of "durability (friction / delamination)," "high-frequency response (large volume / high stiffness)," and "industrial production."

[0008] [Technical Solution] To address the aforementioned technical problems, this invention provides an integrated flexible artificial muscle fiber and its preparation method. Specifically, this invention utilizes a mixture of type A and type B liquid silicone with a hardness of 10-30A to prepare a two-component liquid silicone, which is then pre-cured to obtain a silicone tube. Subsequently, a braided layer is applied, followed by impregnation with the two-component liquid silicone and uniform curing and vulcanization to obtain an integrated flexible artificial muscle fiber. The flexible artificial muscle fiber of this invention eliminates the risks of interlayer friction and delamination, while also possessing high flexibility and high responsiveness. Furthermore, its preparation process is simple and reliable, enabling low-cost mass production.

[0009] The first objective of this invention is to provide a method for preparing integrated flexible artificial muscle fibers, comprising the following steps: S1. Mix type A liquid silica gel and type B liquid silica gel to obtain a two-component liquid silica gel; S2. Mix the two-component liquid silica gel in S1 evenly and remove air bubbles to obtain pretreated two-component liquid silica gel. S3. The pretreated two-component liquid silicone from S2 is placed into an extruder. While extruding the silicone, gas is introduced into the center of the extruder. After injection molding, it is transferred to a heating platform for partial vulcanization to prepare a silicone tube. S4. Coat the outer layer of the silicone tube obtained in S3 with fiber filaments to obtain a silicone tube with an outer layer of fiber filaments. S5. Dip the silicone tube with fiber filaments on the outer layer in S4 into the pretreated two-component liquid silicone in S2, so that the two-component liquid silicone is evenly coated on the surface of the silicone tube to obtain a semi-finished artificial muscle. S6. The semi-finished artificial muscle from step S5 is solidified and vulcanized to obtain integrated flexible artificial muscle fibers.

[0010] In one embodiment of the present invention, in S1, the viscosity of the type A two-component liquid silica gel is 130~150 Pa·s, and the hardness is 10~30A.

[0011] In one embodiment of the present invention, in S1, the viscosity of the type B two-component liquid silica gel is 150~190 Pa·s, and the hardness is 10~30A.

[0012] Preferably, in S1, the viscosity of the type A two-component liquid silica gel is 150 Pa·s and the hardness is 30A; the viscosity of the type B two-component liquid silica gel is 190 Pa·s and the hardness is 30A.

[0013] In one embodiment of the present invention, in S1, type A two-component liquid silica gel and type B two-component liquid silica gel are mixed at a mass ratio of 1:1.

[0014] In one embodiment of the present invention, in S2, uniform mixing is achieved by mixing the sample in a mixer.

[0015] In one embodiment of the present invention, in step S2, the bubbles are mixed and extracted for 20 to 40 minutes.

[0016] In one embodiment of the present invention, in step S3, silica gel is extruded at a flow rate of 0.8 to 1.2 mL / s, and gas is introduced at a flow rate of 0.1 to 0.2 m / s.

[0017] In one embodiment of the present invention, the gas is selected from air or an inert gas.

[0018] In one embodiment of the present invention, the inert gas is selected from one or both of argon and helium.

[0019] In one embodiment of the present invention, in step S3, partial vulcanization is performed at 120-130°C for 2-5 minutes.

[0020] In one embodiment of the present invention, in S4, the outer layer of the fiber filament is prepared by placing the silicone tube obtained in S3 into a braiding machine to prepare an artificial muscle fascia layer, resulting in a semi-finished artificial muscle with a silicone tube inner layer and a fiber outer layer.

[0021] In one embodiment of the present invention, in S4, the fiber filaments are selected from one or more of polyester, nylon, and high molecular weight polyethylene.

[0022] In one embodiment of the present invention, in S4, the fiber is a monofilament or a multifilament.

[0023] In one embodiment of the present invention, the diameter of the monofilament is 0.05~0.2 mm; the thickness of the multifilament is 50~400 D, and it is composed of 30~96 monofilaments.

[0024] In one embodiment of the present invention, the number of weaving paths of the fiber filaments in S4 is 24 or 48, the weaving structure is 1+1 or 1+2, and the weaving pitch is 0.8~3 mm.

[0025] In one embodiment of the present invention, the 1+1 path is a loop that interweaves around the central axis in a "one up, one down" pattern; the 1+2 path is a loop that interweaves around the central axis in a "one up, two down" pattern.

[0026] In one embodiment of the present invention, in step S5, the immersion time is 2-3 minutes, and the coating amount is 0.05-0.06 g / cm³. 2 .

[0027] In one embodiment of the present invention, in step S5, dip coating involves placing the object into a dip coating machine to coat it with an outer layer of silicone.

[0028] In one embodiment of the present invention, in step S6, the curing temperature is 130~150°C and the time is 90~120 min.

[0029] A second objective of this invention is to provide an integral flexible artificial muscle fiber prepared according to the above method.

[0030] A third objective of this invention is to provide the method for preparing the above-described integrated flexible artificial muscle fiber or the application of the above-described integrated flexible artificial muscle fiber in the preparation of robot actuators, wearable devices, bionic devices or medical devices.

[0031] A fourth objective of this invention is to provide a long-life flexible actuator, comprising the integrated flexible artificial muscle fiber.

[0032] In one embodiment of the present invention, a control unit is also included.

[0033] The fifth objective of this invention is to provide a method for simultaneously improving the durability, high-frequency responsiveness, and flexibility of artificial muscle fibers, comprising the following steps: S1. Mix type A liquid silica gel and type B liquid silica gel to obtain a two-component liquid silica gel; S2. Mix the two-component liquid silica gel in S1 evenly and remove air bubbles to obtain pretreated two-component liquid silica gel. S3. The pretreated two-component liquid silicone from S2 is placed into an extruder. While extruding the silicone, gas is introduced into the center of the extruder. After injection molding, it is transferred to a heating platform for partial vulcanization to prepare a silicone tube. S4. Coat the outer layer of the silicone tube obtained in S3 with fiber filaments to obtain a silicone tube with an outer layer of fiber filaments. S5. Dip the silicone tube with fiber filaments on the outer layer in S4 into the pretreated two-component liquid silicone in S2, so that the two-component liquid silicone is evenly coated on the surface of the silicone tube to obtain a semi-finished artificial muscle. S6. The semi-finished artificial muscle from step S5 is solidified and vulcanized to obtain integrated flexible artificial muscle fibers.

[0034] In one embodiment of the present invention, in S1, the viscosity of the type A two-component liquid silica gel is 130~150 Pa·s, and the hardness is 10~30A.

[0035] In one embodiment of the present invention, in S1, the viscosity of the type B two-component liquid silica gel is 150~190 Pa·s, and the hardness is 10~30A.

[0036] Preferably, in S1, the viscosity of type A two-component liquid silica gel is 150 Pa·s and the hardness is 30A; the viscosity of type B two-component liquid silica gel is 190 Pa·s and the hardness is 30A. In one embodiment of the present invention, in S1, type A two-component liquid silica gel and type B two-component liquid silica gel are mixed at a mass ratio of 1:1.

[0037] In one embodiment of the present invention, in S2, uniform mixing is achieved by mixing the sample in a mixer.

[0038] In one embodiment of the present invention, in step S2, the bubbles are mixed and extracted for 20 to 40 minutes.

[0039] In one embodiment of the present invention, in step S3, silica gel is extruded at a flow rate of 0.8 to 1.2 mL / s, and gas is introduced at a flow rate of 0.1 to 0.2 m / s.

[0040] In one embodiment of the present invention, the gas is selected from air or an inert gas.

[0041] In one embodiment of the present invention, the inert gas is selected from one or both of argon and helium.

[0042] In one embodiment of the present invention, in step S3, partial vulcanization is performed at 120-130°C for 2-5 minutes.

[0043] In one embodiment of the present invention, in S4, the outer layer of the fiber filament is prepared by placing the silicone tube obtained in S3 into a braiding machine to prepare an artificial muscle fascia layer, resulting in a semi-finished artificial muscle with a silicone tube inner layer and a fiber outer layer.

[0044] In one embodiment of the present invention, in S4, the fiber filaments are selected from one or more of polyester, nylon, and high molecular weight polyethylene.

[0045] In one embodiment of the present invention, in S4, the fiber is a monofilament or a multifilament.

[0046] In one embodiment of the present invention, the diameter of the monofilament is 0.05 to 0.2 mm; the thickness of the multifilament is 50 to 400D, and it is composed of 30 to 96 monofilaments.

[0047] In one embodiment of the present invention, in S4, the number of weaving paths of the fiber filaments is 24 or 48, the weaving structure is 1+1 or 1+2, and the weaving pitch is 0.8~3 mm.

[0048] In one embodiment of the present invention, the 1+1 path is a loop that interweaves around the central axis in a "one up, one down" pattern; the 1+2 path is a loop that interweaves around the central axis in a "one up, two down" pattern.

[0049] In one embodiment of the present invention, in step S5, dip coating involves placing the object into a dip coating machine to coat it with an outer layer of silicone.

[0050] In one embodiment of the present invention, in step S5, the immersion time is 2-3 minutes, and the coating amount is 0.05 g / cm³. 2 ~0.06 g / cm 2 .

[0051] In one embodiment of the present invention, in step S6, the curing temperature is 130~150°C and the time is 90~120 min.

[0052] [Beneficial Effects] (1) The method for preparing the integrated artificial muscle proposed in this invention includes four key steps: pretreatment of silicone material, preparation of the inner silicone tube of the artificial muscle, weaving process of the fascia layer of the artificial muscle, and silicone impregnation process of the outer silicone layer of the artificial muscle. Figure 1 , Figure 2 The entire process utilizes industrialized machinery, significantly improving production efficiency and providing a technological foundation for the large-scale production of artificial muscles.

[0053] (2) The one-piece flexible artificial muscle prepared by this invention using silicone with a Shore hardness of 30A can achieve a contraction rate of up to 20%, and a single artificial muscle can withstand a tensile force of 200N, provide a driving force of 20N, and achieve a stable response within a frequency range of 50Hz. This invention optimizes the vulcanization step in the preparation method, using two vulcanization processes to achieve a tight bond between the inner silicone tube, the braided layer, and the outer silicone tube into a whole, thus obtaining an one-piece artificial muscle. Figure 3 ).

[0054] (3) The integrated artificial muscle provided by this invention will not break even during long-term use, and its cycle life can reach more than 1.1 million to 5.2 million cycles, which is dozens of times longer than that of commercially available artificial muscles (usually less than 100,000 cycles). Even under load, its cycle life still remains at the level of 110,000 to 970,000 cycles, solving the two core problems of lifespan and performance of artificial muscles in the prior art. It has great application potential in cutting-edge fields such as robotics, high-end medical devices, and intelligent prostheses. Attached Figure Description

[0055] Figure 1 A schematic flowchart of a method for preparing an integrated flexible artificial muscle, provided as an exemplary embodiment of this application; Figure 2 A schematic diagram of a method for preparing an integrated flexible artificial muscle, provided as an exemplary embodiment of this application; Figure 3 The images show the microstructure of the integrated flexible artificial muscle under a microscope. In the images, A represents the overall appearance of the artificial muscle prepared in Example 1, B represents the cross-section of the artificial muscle prepared in Example 1, and C represents the surface of the artificial muscle prepared in Example 1. Detailed Implementation

[0056] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explanation of the present invention and are not intended to limit the present invention.

[0057] Test method: 1. Tensile strength at break: According to the national standard GB / T 4146.2-2017, the tensile strength of artificial muscle at break was determined. 2. Driving force: One end of the artificial muscle is fixed, and the other end is fixed to the tension meter. The length of the artificial muscle remains unchanged. The artificial muscle is inflated (air pressure is 80kPa, 150kPa, 300kPa) and contracted. The values ​​displayed on the tension meter are then observed. 3. Shrinkage rate: Artificial muscles perform a contraction and extension movement during inflation and deflation at different frequencies (2, 5, 10, 25, 50 Hz); Artificial muscles perform a contraction and extension movement during inflation and deflation at different air pressures (80kPa, 150kPa, 300kPa); Contraction rate = Length of artificial muscle contraction ÷ Original length × 100%; 4. Durability (number of cycles): One end of the artificial muscle is fixed, and the other end is placed flat on the test table. One inflation and deflation is one cycle. Inflation and deflation are controlled at different air pressures (80kPa, 150kPa, 300kPa). 5. Viscosity: The measurements were taken using a rotational viscometer.

[0058] Raw materials used in the examples: Both Type A and Type B liquid silicone were purchased from Shenzhen Jereh New Materials Co., Ltd.

[0059] Example 1 A method for preparing integrated flexible artificial muscle fibers includes the following steps: S1. Mix type A liquid silica gel with a hardness of 30A and a viscosity of 150 Pa·s and type B liquid silica gel with a hardness of 30A and a viscosity of 190 Pa·s at a mass ratio of 1:1 to obtain a two-component liquid silica gel. S2. The two-component liquid silica gel in S1 is placed into a planetary power mixer DH5-2000L for mixing and bubble removal for 30 min to obtain pretreated two-component liquid silica gel with a viscosity of 180 Pa·s. S3. The pretreated two-component liquid silicone from S2 is placed in a 65-type horizontal silicone extruder and extruded at a flow rate of 0.8 mL / s. At the same time, air is introduced into the center of the extruder at a flow rate of 0.1 m / s. After injection molding, the silicone is transferred to a heating platform and cured at 130℃ for 3 min to obtain a silicone tube with a wall thickness of 0.5 mm, an outer diameter of 5 mm, and an inner diameter of 4 mm. S4. Place the silicone tube obtained in S3 into a horizontal braiding machine KBW-90-48-1, and braid it using polyester monofilament with a diameter of 0.1 mm. The number of braids is 48, the braiding structure is 1+2, and the braiding pitch is 1.2 mm to obtain a silicone tube with an outer layer of fiber. S5. Place the silicone tube with the outer fiber coating obtained in S4 into an Rjy-00 / 800 dip-coating machine, and dip-coat it with the two-component liquid silicone with a viscosity of 180 Pa·s pretreated in S2 for 2 minutes. The coating amount is 0.05 g / cm³. 2 This allows the two-component liquid silicone to be evenly coated on the surface of the silicone tube covered with fibers, resulting in a semi-finished artificial muscle. S6. Place the semi-finished artificial muscle from step S5 into an oven and cure it at 140°C for 90 minutes to obtain an integrated artificial muscle with an outer diameter of 6 mm.

[0060] The resulting integrated artificial muscle underwent performance testing, and the results are as follows: Table 1. High-frequency performance results of Example 1

[0061] Example 2 A method for preparing integrated flexible artificial muscle fibers includes the following steps: S1. Mix type A liquid silica gel with a hardness of 30A and a viscosity of 150 Pa·s and type B liquid silica gel with a hardness of 30A and a viscosity of 190 Pa·s at a mass ratio of 1:1 to obtain a two-component liquid silica gel. S2. The two-component liquid silica gel in S1 is placed into a planetary power mixer DH5-2000L for mixing and bubble removal for 30 min to obtain pretreated two-component liquid silica gel with a viscosity of 180 Pa·s. S3. The pretreated two-component liquid silicone from S2 is placed in a 65-type horizontal silicone extruder and extruded at a flow rate of 1.2 mL / s. At the same time, air is introduced into the center of the extruder at a flow rate of 0.1 m / s. After injection molding, the silicone is transferred to a heating platform and cured at 130℃ for 3 min to obtain a silicone tube with a wall thickness of 0.5 mm, an outer diameter of 5 mm, and an inner diameter of 4 mm. S4. Place the silicone tube obtained in S3 into a horizontal braiding machine KBW-90-48-1 and braid it using 75D nylon multifilament (composed of 36 nylon monofilaments). The number of braids is 48, the braiding structure is 1+2, and the braiding pitch is 2.2 mm to obtain a silicone tube with an outer layer of fiber coating. S5. Place the semi-finished artificial muscle obtained in S4 into an Rjy-00 / 800 dip-coating machine, and dip-coat it with the two-component liquid silicone with a viscosity of 180 Pa·s pretreated in S2 for 2 minutes. The coating amount is 0.05 g / cm³. 2 This allows the two-component liquid silicone to be evenly coated on the surface of the silicone tube covered with fibers, resulting in a semi-finished artificial muscle. S6. Place the semi-finished artificial muscle from step S5 into an oven and cure it at 140°C for 90 minutes to obtain an integrated artificial muscle with an outer diameter of 6mm.

[0062] Example 3 A method for preparing integrated flexible artificial muscle fibers includes the following steps: S1. Mix type A liquid silica gel with a hardness of 30A and a viscosity of 150 Pa·s and type B liquid silica gel with a hardness of 30A and a viscosity of 190 Pa·s at a mass ratio of 1:1 to obtain a two-component liquid silica gel. S2. The two-component liquid silica gel in S1 is placed into a planetary power mixer DH5-2000L for mixing and bubble removal for 30 min to obtain pretreated two-component liquid silica gel with a viscosity of 180 Pa·s. S3. The pretreated two-component liquid silicone from S2 is placed in a 65-type horizontal silicone extruder and extruded at a flow rate of 0.8 mL / s. At the same time, air is introduced into the center of the extruder at a flow rate of 0.2 m / s. After injection molding, the silicone is transferred to a heating platform and cured at 120℃ for 5 min to obtain a silicone tube with a wall thickness of 0.5 mm, an outer diameter of 9 mm, and an inner diameter of 8 mm. S4. Place the silicone tube obtained in S3 into a horizontal braiding machine KBW-90-48-1, and braid it using polyester monofilament with a diameter of 0.1 mm. The number of braids is 48, the braiding structure is 1+2, and the braiding pitch is 1.2 mm to obtain a silicone tube with an outer layer of fiber. S5. Place the silicone tube with the outer fiber coating obtained in S4 into an Rjy-00 / 800 dip-coating machine, and dip-coat it with the two-component liquid silicone with a viscosity of 180 Pa·s pretreated in S2 for 2 minutes. The coating amount is 0.05 g / cm³. 2 This allows the two-component liquid silicone to be evenly coated on the surface of the silicone tube covered with fibers, resulting in a semi-finished artificial muscle. S6. Place the semi-finished artificial muscle from step S5 into an oven and cure it at 140°C for 90 minutes to obtain an integrated artificial muscle with an outer diameter of 10mm.

[0063] Comparative Example 1 The difference from Example 1 is as follows: Omit S3; Replace the two-component liquid silicone in S4 with a commercially available single-layer silicone tube (wall thickness 0.5 mm, outer diameter 5 mm, inner diameter 4 mm), and directly weave the polyester monofilament onto the commercially available silicone tube, followed by impregnation with the two-component liquid silicone in S2.

[0064] The results showed that the manufactured artificial muscles hardly contracted or deformed under pressures exceeding 500 kPa. This was because the commercially available single-layer silicone tubes had high hardness and could not meet the radial expansion required for artificial muscle contraction.

[0065] Comparative Example 2 The difference from Example 1 is as follows: S1, S2, and S3 are omitted; Replace the two-component liquid silicone in S4 with a commercially available single-layer silicone tube (0.5 mm wall thickness, 5 mm outer diameter, 4 mm inner diameter). Weave the polyester monofilament directly onto the commercially available silicone tube, and then cover it with a commercially available silicone tube (0.5 mm wall thickness, 6 mm outer diameter, 5 mm inner diameter).

[0066] The results showed that the manufactured artificial muscles hardly contracted or deformed under pressures exceeding 500 kPa. This was because the commercially available single-layer silicone tubes had high hardness and could not meet the radial expansion required for artificial muscle contraction.

[0067] Comparative Example 3 The difference from Example 1 is as follows: Choose type A liquid silica gel with a hardness of 40A (viscosity of 160 Pa·s) or type B liquid silica gel with a hardness of 40A (viscosity of 195 Pa·s).

[0068] The results showed that the artificial muscle had a smaller contraction rate and generated less driving force under an air pressure of 300 kPa.

[0069] Comparative Example 4 The difference from Example 1 is as follows: Choose type A liquid silica gel with a hardness of 50A (viscosity of 170 Pa·s) or type B liquid silica gel with a hardness of 50A (viscosity of 200 Pa·s).

[0070] The results showed that the artificial muscle had a very small contraction rate of only about 5% under a pressure of 300 kPa, and generated even less driving force.

[0071] Comparative Example 5 The difference from Example 1 is as follows: Set the temperature of the heating platform in S3 to 70℃ and the time to 3 minutes.

[0072] The results showed that the silicone tube could not be cured and could not be formed.

[0073] Comparative Example 6 The difference from Example 1 is as follows: Set the temperature of the heating platform in S3 to 170℃ and the time to 3 minutes.

[0074] The results showed that the silicone tube was completely cured and formed, but it was prone to peeling off from the second silicone coating layer, affecting the lifespan of the artificial muscle.

[0075] Comparative Example 7 The difference from Example 1 is as follows: Set the heating platform time in S3 to 20 min and the temperature to 130℃.

[0076] The results showed that the silicone tube was completely cured and formed, but it was prone to peeling off from the second silicone coating layer, affecting the lifespan of the artificial muscle.

[0077] Comparative Example 8 The difference from Example 1 is as follows: Set the heating platform time in S3 to 90 min and the temperature to 130℃.

[0078] The results showed that the silicone tube was completely cured and formed, but it could not be bonded to the second silicone coating layer, and an integrated artificial muscle could not be prepared.

[0079] Comparative Example 9 The difference from Example 1 is as follows: Set the weaving pitch in S4 to 0.8 mm. The results showed that under a pressure of 300 kPa, the artificial muscle had a low contraction rate and low driving force, resulting in weakened performance.

[0080] Comparative Example 10 The difference from Example 1 is as follows: Set the weaving pitch in S4 to 2 mm.

[0081] The results showed that under a pressure of 300 kPa, the artificial muscle expanded radially, increased its driving force, and had a smaller contraction rate.

[0082] Comparative Example 11 The difference from Example 1 is as follows: Type A two-component liquid silica gel has a viscosity of 20 Pa·s and a Shore hardness of 10A; Type B two-component liquid silica gel has a viscosity of 25 Pa·s and a Shore hardness of 10A.

[0083] The results showed that the maximum air pressure of the artificial muscle could only reach 80 kPa, and the contraction rate was 28%.

[0084] Test case Performance tests were conducted on the artificial muscles obtained in the examples and comparative examples. The results of tensile strength at break, driving performance, contraction rate, and durability tests are shown in Tables 2-5.

[0085] Table 2 Tensile strength test at break

[0086] Table 3 Drive Performance Test

[0087] Table 4 Shrinkage Test

[0088] Table 5 Durability Test

[0089] Note: " / " indicates that a suitable sample could not be prepared or the measurement range was exceeded. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for preparing integrated flexible artificial muscle fibers, characterized in that, Includes the following steps: S1. Mix type A liquid silica gel and type B liquid silica gel at a mass ratio of 1:1 to obtain a two-component liquid silica gel; the viscosity of the type A two-component liquid silica gel is 130~150 Pa. The hardness of type B two-component liquid silica gel is 10~30A; the viscosity of type B is 150~190Pa. s, with a hardness of 10~30A; S2. Mix the two-component liquid silica gel in S1 evenly and remove air bubbles to obtain pretreated two-component liquid silica gel. S3. Place the pretreated two-component liquid silicone from S2 into an extruder. While extruding the silicone, introduce gas into the center of the extruder. After injection molding, transfer it to a heating platform and partially vulcanize at 120~130℃ for 2~5 min to obtain a silicone tube. S4. Coat the outer layer of the silicone tube obtained in S3 with fiber filaments to obtain a silicone tube with an outer layer of fiber filaments. S5. Dip the silicone tube with fiber filaments on the outer layer in S4 into the pretreated two-component liquid silicone in S2, so that the two-component liquid silicone is evenly coated on the surface of the silicone tube to obtain a semi-finished artificial muscle. S6. The semi-finished artificial muscle from step S5 is solidified and vulcanized to obtain integrated flexible artificial muscle fibers.

2. The method according to claim 1, characterized in that, In S3, silica gel is extruded at a flow rate of 0.8~1.2 mL / s, and gas is introduced at a flow rate of 0.1~0.2 m / s.

3. The method according to claim 1, characterized in that, In S4, the fibers are either monofilaments or multifilaments.

4. The method according to claim 3, characterized in that, The fiber filaments are selected from one or more of polyester, nylon, and high molecular weight polyethylene.

5. The method according to claim 3, characterized in that, The diameter of the monofilament is 0.05 ~ 0.2 mm; the thickness of the multifilament is 50 ~ 400D.

6. The method according to claim 1 or 4, characterized in that, The fiber filaments have 24 or 48 weaves, a 1+1 or 1+2 weave structure, and a weave pitch of 0.8 to 3 mm.

7. The method according to claim 1, characterized in that, In S5, the immersion time is 2-3 minutes, and the coating amount is 0.05 g / cm³. 2 ~0.06 g / cm 2 In S6, curing and vulcanization are carried out at 130~150℃ for 90~120 min.

8. The integrated flexible artificial muscle fiber prepared by the method according to any one of claims 1 to 7.

9. The application of the method of any one of claims 1 to 7 or the integrated flexible artificial muscle fiber of claim 8 in the preparation of robot actuators, wearable devices, bionic devices or medical devices.

10. A long-life flexible actuator, characterized in that, Includes the integrated flexible artificial muscle fiber as described in claim 8; It also includes a control unit.

11. A method for simultaneously improving the durability, high-frequency responsiveness, and flexibility of artificial muscle fibers, characterized in that, Includes the following steps: S1. Mix type A liquid silica gel and type B liquid silica gel to obtain a two-component liquid silica gel; S2. Mix the two-component liquid silica gel in S1 evenly and remove air bubbles to obtain pretreated two-component liquid silica gel. S3. Place the pretreated two-component liquid silicone from S2 into an extruder. While extruding the silicone, introduce gas into the center of the extruder. After injection molding, transfer it to a heating platform and partially vulcanize at 120~130℃ for 2~5 minutes to obtain a silicone tube. S4. Coat the outer layer of the silicone tube obtained in S3 with fiber filaments to obtain a silicone tube with an outer layer of fiber filaments. S5. Dip the silicone tube with fiber filaments on the outer layer in S4 into the pretreated two-component liquid silicone in S2, so that the two-component liquid silicone is evenly coated on the surface of the silicone tube to obtain a semi-finished artificial muscle. S6. The semi-finished artificial muscle in step S5 is solidified and vulcanized to obtain an integrated flexible artificial muscle fiber. Among them, the viscosity of type A two-component liquid silica gel is 130~150 Pa. The hardness of type B two-component liquid silica gel is 10~30A; the viscosity of type B is 150~190Pa. s, with a hardness of 10~30A.

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