A photoactuator and a method for preparing the same

Abstract

The present invention belongs to the technical field of cardiac contraction assist devices and relates to a photoactuator and its preparation method. The photoactuator comprises a serrated silicone membrane, a silicone wire, an optical fiber, and a liquid crystal elastomer fiber. The preparation method comprises the following steps: (a) inserting a pore-forming wire of the same shape and size as the silicone wire into a mold cavity of the same shape and size as the serrated silicone membrane, pouring uncured first silicone into the cavity, and then heating and curing, demolding, and removing the pore-forming wire to obtain a serrated silicone membrane with through holes; (b) pouring uncured second silicone into the through holes of the serrated silicone membrane with through holes, simultaneously inserting an optical fiber into the rear end of each through hole, and then heating and curing to obtain a semi-finished product consisting of the serrated silicone membrane, silicone wire, and optical fiber; and (c) connecting the liquid crystal elastomer fiber to the front end of the serrated silicone membrane to obtain the photoactuator. The photoactuator of the present invention can align with the frequency and timing of ventricular contraction, meeting the requirements of assisting cardiac contraction.

Description

Technical Field

[0001] The present invention belongs to the technical field of cardiac contraction assist devices and relates to a photoactuator and a preparation method thereof. Background Art

[0002] Heart diseases such as heart failure can lead to a weakening of myocardial contractility, making it impossible for the heart to effectively pump enough blood throughout the body. Cardiac contraction assist devices can apply auxiliary force externally to increase the squeezing force during cardiac contraction, significantly increasing the heart's stroke volume, ensuring that all organs in the body receive an adequate blood supply, and alleviating a series of symptoms caused by insufficient blood supply, such as fatigue and difficulty breathing. For a damaged heart, the cardiac contraction assist device shares some of the work of pumping blood, reducing the resistance that the heart itself needs to overcome, and reducing the energy consumed by the heart in maintaining blood circulation, which helps the myocardium to recover and repair to a certain extent, and delays further deterioration of heart function. Therefore, research on cardiac contraction assist devices is of great significance.

[0003] Patent CN115869531B discloses an implantable ventricular assist device (VAD) comprising a retractable sleeve that surrounds the entire heart, a main system processing mechanism, a pressure monitoring sensor assembly, and an energy source assembly. The pressure monitoring sensor assembly is mounted on the heart's arterial wall and electrically connected to the main system processing mechanism, which in turn is electrically connected to the retractable sleeve. The energy source assembly is electrically connected to the main system processing mechanism. The retractable sleeve primarily comprises a plurality of interconnected finger joints, each with a proximal end and a distal end. The finger joints expand when powered off and radially rotate from the proximal end to the distal end to compress the heart when powered on. This VAD assists the heart in a direction consistent with the normal physiological contraction of the ventricular myocardium, thereby enhancing the hemodynamic effect of each pumping contraction and reducing the degree of damage to the heart caused by the VAD.

[0004] Patent application CN117442867A discloses a cardiac contraction assist device and its control method. The cardiac contraction assist device comprises: an open mouth, comprising a first cavity, a second cavity, and a third cavity, formed sequentially from the inside out. The first cavity is open at one end and is used to accommodate the heart. Both the second cavity and the first cavity are deformable. The third cavity is a spatially confined cavity and is connected to the second cavity. A pair of driving electrodes is disposed within the third cavity and is configured to generate an electrostatic attraction force that reduces the distance between them when connected to a power source. A deformable cavity, adapted to accommodate a flowable target medium, comprises a first section and a second section. The first section is located within the second cavity, and the second section is located within the third cavity and is at least partially distributed between the pair of driving electrodes. The first section drives the second and first cavities to deform toward or away from the heart in response to changes in the volume of the second section. The device assists contraction of different cardiac regions and offers excellent safety.

[0005] All of the aforementioned cardiac support devices are electric actuators. However, the electric field distribution of electric actuators is relatively diffuse, making it difficult to focus on a very small area. This makes it impossible to precisely control the actuation of specific tiny parts, and their spatial resolution is low. Some electric actuators, such as those based on the electrothermal effect, have a slow response speed due to delayed heat transfer. In biomedical implant applications, electric actuators pose potential risks. For example, electrical signals may trigger electrolysis or electrochemical reactions, leading to electrode corrosion. The generated metal ions or other products may be toxic to biological tissues, triggering inflammation or immune responses. Electric actuators may also generate electromagnetic interference during operation, affecting the normal operation of other nearby electronic equipment. In some special environments, such as magnetic resonance imaging rooms in hospitals, electromagnetic interference can have serious consequences. Therefore, the low spatial resolution, slow response speed, and potential risks will further limit the application of electric actuators.

[0006] Therefore, it is necessary to develop a non-electrically driven actuator. Summary of the Invention

[0007] The purpose of the present invention is to solve the above problems existing in the prior art and to provide a photoactuator and a method for preparing the same.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] A photoactuator comprising a sawtooth silicone film, a silicone wire, an optical fiber, and a liquid crystal elastomer fiber;

[0010] The serrated silicone membrane is arranged horizontally, and the longitudinal section parallel to the left-right direction is serrated, and the longitudinal section parallel to the front-back direction is straight;

[0011] There are multiple silicone lines, which are located inside the serrated silicone film, and the front end is not blocked by the serrated silicone film;

[0012] The refractive index of the silicone thread is higher than that of the serrated silicone film;

[0013] The number of optical fibers is the same as that of silicone wires, and the two correspond one to one. The front end of the optical fiber is inserted into the back end of the corresponding silicone wire;

[0014] The liquid crystal elastomer fiber is in a straight state and is located in front of the silicone wire, and is used to receive the infrared laser emitted from the front end of the silicone wire;

[0015] The liquid crystal elastomer fibers shrink when irradiated by the infrared laser and rebound after the infrared laser irradiation is removed;

[0016] The liquid crystal elastomer fiber is connected to the serrated silicone membrane in a manner such that: when the liquid crystal elastomer fiber contracts, the serrated silicone membrane contracts accordingly; when the liquid crystal elastomer fiber rebounds, the serrated silicone membrane rebounds accordingly.

[0017] An optical waveguide is a structure or medium that guides the propagation of light waves. It generally consists of a core layer and a cladding layer. Its principle is based on the total internal reflection of light. When light travels from a medium with a high refractive index to a medium with a low refractive index, under certain incident angles, it undergoes total internal reflection at the interface between the two media. This confines the light to the high-refractive-index core layer, allowing it to travel long distances with minimal loss.

[0018] In the present invention, since "there are multiple silicone wires located inside the serrated silicone film" and "the refractive index of the silicone wire is higher than that of the serrated silicone film", the serrated silicone film and the silicone wires together constitute an optical waveguide, the serrated silicone film is the cladding of the optical waveguide, and the silicone wires are the core layer of the optical waveguide.

[0019] In the present invention, because "the front ends of the optical fibers are inserted into the rear ends of the corresponding silicone threads," when all optical fibers are uniformly connected to an 808nm infrared laser, the infrared laser will be transmitted along the optical fibers, emitted from the front ends of the optical fibers, coupled into the silicone threads, and transmitted along the silicone threads by total internal reflection. Because "the front ends of the silicone threads are not obstructed by the jagged silicone film" and "the liquid crystal elastomer fibers are straightened, located in front of the silicone threads, and are used to receive light emitted from the front ends of the silicone threads," the infrared laser will be emitted from the front ends of the silicone threads and shine on the liquid crystal elastomer fibers. When the liquid crystal elastomer fibers receive the infrared laser light, they absorb the energy of the infrared laser light, causing their temperature to rise. When their temperature exceeds the phase transition temperature, they contract. When the infrared laser light is turned off, they dissipate heat, causing their temperature to drop below the transition temperature, and they rebound. Since "the serrated silicone membrane is arranged horizontally, the longitudinal section parallel to the left and right directions is serrated, and the longitudinal section parallel to the front and back directions is straight", "the liquid crystal elastomer fiber is connected to the serrated silicone membrane and the connection method satisfies: when the liquid crystal elastomer fiber contracts, the serrated silicone membrane contracts accordingly; when the liquid crystal elastomer rebounds, the serrated silicone membrane rebounds accordingly", therefore when the liquid crystal elastomer fiber contracts, the serrated silicone membrane contracts accordingly; when the liquid crystal elastomer rebounds, the serrated silicone membrane rebounds accordingly.

[0020] Currently, most cardiac contraction assist devices are integral cardiac contraction assist devices, which wrap around the entire or most of the surface of the heart to achieve comprehensive assistance to cardiac contraction.

[0021] However, the above-mentioned integral auxiliary contraction device has the following disadvantages:

[0022] (1) The atria and ventricles of the heart have a strict and asynchronous contraction and relaxation rhythm. The atria contract first, squeezing blood into the ventricles, and then the ventricles contract, pumping blood out of the heart. The whole-body auxiliary contraction device cannot distinguish the different contraction timings of the atria and ventricles. At the same time, the auxiliary contraction may cause the contraction order of the atria and ventricles to be disordered, which not only disrupts the normal pumping function of the heart, but also may cause blood backflow, increase the pressure inside the heart, and reduce the overall pumping efficiency of the heart.

[0023] (2) The heart's rhythm is regulated by multiple factors, including the autonomic nervous system and the heart's own electrophysiological mechanisms. Overall auxiliary contraction may interfere with the heart's normal heart rate regulation mechanism, making it difficult for the heart to make appropriate heart rate adjustments under different physiological states (such as rest and exercise), hindering the heart's own heart rate regulation function and making it unable to adapt to various activity states of the body.

[0024] The serrated silicone membrane of the photoactuator of this invention can be sutured to the ventricle. By controlling the on and off of the infrared laser, the frequency and timing of the photoactuator's contraction and rebound are controlled, aligning them with the frequency and timing of ventricular contraction, thereby assisting ventricular contraction. The photoactuator of this invention specifically assists ventricular contraction, overcoming the limitation of traditional ventricular contraction-assisting devices that cannot act specifically on the ventricle. This avoids the potential problems caused by simultaneous contraction of the ventricles and atria, and is of great significance for the treatment of myocardial infarction.

[0025] As the preferred technical solution:

[0026] In the above-mentioned optical actuator, the difference in refractive index between the silicone wire and the sawtooth silicone film is 0.05-0.2.

[0027] In the photoactuator described above, the serrated silicone membrane is an integrally molded part with a thickness of 100-1000 μm, which is convenient for processing and molding and can also avoid the deterioration of the contraction effect due to excessive thickness; the length and width of the serrated silicone membrane are related to the size of the atrium / ventricle.

[0028] In the photoactuator described above, the silicone wire is an integrally molded part with a diameter of 50-500 μm. This facilitates processing and molding and avoids the deterioration of the shrinkage effect due to an excessively large diameter. In addition, since the silicone wire is located inside the serrated silicone membrane, the diameter of the silicone wire needs to be smaller than the thickness of the serrated silicone membrane.

[0029] In the optical actuator described above, the insertion depth of the front end of the optical fiber into the rear end of the corresponding silicone wire is 1-2 mm. This can avoid the poor flexibility of the optical actuator due to excessive insertion depth, and can also avoid the loose connection and easy disconnection due to insufficient insertion depth.

[0030] In a photoactuator as described above, the phase transition temperature of the liquid crystal elastomer fiber is 60-90°C. At this time, when the temperature of the liquid crystal elastomer fiber exceeds the phase transition temperature, it will shrink, and the shrinkage is close to 40%; it responds quickly to light and can complete the contraction action in about 250 milliseconds; if the phase transition temperature is too high, the heating time becomes longer and the contraction becomes slower; if the phase transition temperature is too low and the difference from the body's ambient temperature is too small, the cooling time becomes longer and the rebound becomes slower.

[0031] In the above-mentioned photoactuator, the distance between the liquid crystal elastomer fiber and the silicone wire is 500-2000 μm.

[0032] In a photoactuator as described above, the liquid crystal elastomer fiber is bonded to the serrated silicone film, the number of bonding points is more than 2 and they are arranged at intervals along the length direction of the liquid crystal elastomer fiber, one bonding point is located at the left end of the liquid crystal elastomer fiber and the left front end of the serrated silicone film, and one bonding point is located at the right end of the liquid crystal elastomer fiber and the right front end of the serrated silicone film.

[0033] The present invention also provides a method for preparing a photoactuator as described in any one of the above items, comprising the following steps:

[0034] (a) adding a pore-forming wire having the same shape and size as the silicone wire into a mold cavity having the same shape and size as the serrated silicone membrane, pouring uncured first silicone into the mold cavity, and then heating and curing, demolding, and extracting the pore-forming wire in sequence to obtain a serrated silicone membrane with through holes;

[0035] (b) pouring uncured second silicone into the through holes of the serrated silicone membrane with through holes, inserting an optical fiber into the rear end of each through hole, and then heating and curing the resultant product to obtain a semi-finished product consisting of the serrated silicone membrane, the silicone wire, and the optical fiber;

[0036] (c) The liquid crystal elastomer fiber is connected to the front end of the serrated silicone membrane to obtain a photoactuator.

[0037] Beneficial effects:

[0038] (1) The optical actuator of the present invention controls the frequency and timing of contraction and rebound of the optical actuator by controlling the on and off of the infrared laser in the optical fiber, which can be aligned with the frequency and timing of ventricular contraction, thereby playing the role of assisting ventricular contraction.

[0039] (2) Compared with the electric actuators in the prior art, the optical actuator of the present invention has higher spatial resolution due to the high focusing characteristics of light; the optical actuator uses light as energy, has better biocompatibility, and has less adverse effects on surrounding biological tissues; the optical signal propagates extremely fast, and the materials in the optical actuator respond quickly to light, and can complete the action in about 250 milliseconds. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of the three-dimensional structure of the optical actuator of the present invention;

[0041] Figures 2 to 4 1 is a view of the optical actuator of the present invention from different angles;

[0042] Figure 5 is a graph showing the change in contraction amplitude over time of a single liquid crystal elastomer fiber used in the photoactuator of Example 1B of the present invention after being irradiated with an 808 nm infrared laser;

[0043] Figure 6 is a simulation test result of the contraction amplitude of the optical actuator of the present invention;

[0044] In the figure, 1 is a liquid crystal elastomer fiber, 2 is a serrated silicone film, 3 is an optical fiber, and 4 is a silicone wire. DETAILED DESCRIPTION

[0045] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0046] Example 1A

[0047] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4 The optical actuator shown is composed of a sawtooth silicone film 2, a silicone wire 4, an optical fiber 3 and a liquid crystal elastomer fiber 1;

[0048] The serrated silicone membrane 2 is arranged horizontally, and the longitudinal section parallel to the left-right direction is serrated, and the longitudinal section parallel to the front-back direction is straight. The serrated silicone membrane 2 is an integrally formed part with a thickness of 100 μm.

[0049] There are 8 silicone wires 4, which are located inside the serrated silicone membrane 2 and have no serrated silicone membrane 2 blocking their front ends. The silicone wires 4 are integrally formed parts with a diameter of 50 μm.

[0050] The refractive index of the silicone wire 4 is higher than that of the serrated silicone film 2; the difference in refractive index between the silicone wire 4 and the serrated silicone film 2 is 0.05;

[0051] The number of optical fibers 3 is the same as that of silicone wires 4, and the two correspond one to one. The front end of the optical fiber 3 is inserted into the rear end of the corresponding silicone wire 4; the insertion depth of the front end of the optical fiber 3 into the rear end of the corresponding silicone wire 4 is 1 mm;

[0052] The liquid crystal elastomer fiber 1 is in a straight state and is located in front of the silicone wire 4 to receive the infrared laser emitted from the front end of the silicone wire 4. The phase transition temperature of the liquid crystal elastomer fiber 1 is 60°C. The distance between the liquid crystal elastomer fiber 1 and the silicone wire 4 is 500 μm.

[0053] The liquid crystal elastomer fiber 1 contracts when irradiated by the infrared laser and rebounds after the infrared laser irradiation is removed;

[0054] The liquid crystal elastomer fiber 1 is bonded to the serrated silicone film 2. The number of bonding points is four and they are spaced apart along the length direction of the liquid crystal elastomer fiber 1. One bonding point is located at the left end of the liquid crystal elastomer fiber 1 and the left front end of the serrated silicone film 2, and one bonding point is located at the right end of the liquid crystal elastomer fiber 1 and the right front end of the serrated silicone film 2.

[0055] When the liquid crystal elastomer fiber 1 contracts, the serrated silicone membrane 2 contracts accordingly; when the liquid crystal elastomer fiber 1 rebounds, the serrated silicone membrane 2 rebounds accordingly.

[0056] Example 1B

[0057] A method for preparing a photoactuator of Example 1A comprises the following specific steps:

[0058] (1) Prepare raw materials;

[0059] Pore formation line: diameter 50 μm, number 8;

[0060] Mold: Two serrated metal parts, the mold cavity thickness is 100μm, the shape of the mold cavity is a serrated line in the longitudinal section parallel to the left and right direction, and a straight line in the longitudinal section parallel to the front and back direction;

[0061] The first silica gel and the second silica gel: the refractive index of the first silica gel is higher than that of the second silica gel, and the difference between the refractive indices of the first silica gel and the second silica gel is 0.05;

[0062] Optical fiber: There are 8 of them, and from the inside out they are the core, cladding, and coating. After the coating at one end of the optical fiber is stripped off, only the core and cladding are left as the insertion end. The length of the insertion end is 1mm and the diameter of the insertion end is 50μm.

[0063] Liquid crystal elastomer fiber: phase transition temperature is 60℃, diameter is 200μm, number is 3, and the contraction force of a single liquid crystal elastomer fiber is 0.02N; fix one end of a single liquid crystal elastomer fiber and connect a weight to the other end. Use 808nm infrared laser to irradiate the liquid crystal elastomer fiber. It absorbs laser energy and shrinks. After 3 seconds, the light is stopped. Use a high-speed camera to record and analyze its contraction process. The contraction amplitude of a single liquid crystal elastomer fiber after irradiation with 808nm infrared laser changes with time as shown in the figure. Figure 5As shown, the liquid crystal elastomer fiber responds quickly to light and can complete the contraction action in about 250 milliseconds, meeting the response speed requirement for assisting heart contraction.

[0064] (2) adding a pore-forming line with the same shape and size as the silicone line into a mold cavity with the same shape and size as the serrated silicone membrane, pouring uncured first silicone into it, and then heating and curing, demolding, and extracting the pore-forming line in sequence to obtain a serrated silicone membrane with through holes;

[0065] (3) pouring uncured second silicone into the through holes of the serrated silicone membrane with through holes, and inserting an optical fiber into the rear end of each through hole with an insertion depth of 1 mm, and heating and curing to obtain a semi-finished product consisting of a serrated silicone membrane, a silicone wire, and an optical fiber;

[0066] (4) Connect the liquid crystal elastomer fiber to the front end of the serrated silicone membrane to obtain a photoactuator.

[0067] The solid mechanics simulation module of Comsol Multiphysics was used to perform a precise 1:1 scale 3D model of the optical actuator. A contraction force of 0.06 N (equal to the sum of the contraction forces of three liquid crystal elastomer fibers) was applied to the serrated silicone membrane along the length direction of the liquid crystal elastomer fibers. The contraction amplitude of the serrated silicone membrane was calculated. Contraction amplitude = (deformation of the serrated silicone membrane along the force direction / original length of the serrated silicone membrane along the force direction) × 100%. The contraction amplitude of the serrated silicone membrane was 41%, as shown in Figure 2. Figure 6 shown.

[0068] Example 2A

[0069] A photoactuator is composed of a zigzag silicone film, silicone wire, optical fiber and liquid crystal elastomer fiber;

[0070] The serrated silicone membrane is arranged horizontally, with a longitudinal section parallel to the left-right direction being serrated and a longitudinal section parallel to the front-back direction being straight. The serrated silicone membrane is an integrally formed part with a thickness of 800 μm.

[0071] There are 6 silicone wires, located inside the serrated silicone membrane, and there is no serrated silicone membrane blocking the front end; the silicone wire is an integrally molded part with a diameter of 400μm;

[0072] The refractive index of the silicone wire is higher than that of the serrated silicone film; the difference in refractive index between the silicone wire and the serrated silicone film is 0.1;

[0073] The number of optical fibers is the same as that of silicone wires, and the two correspond one to one. The front end of the optical fiber is inserted into the back end of the corresponding silicone wire; the insertion depth of the front end of the optical fiber into the back end of the corresponding silicone wire is 1.5mm;

[0074] The liquid crystal elastomer fiber is in a straight state and is located in front of the silicone wire to receive the infrared laser emitted from the front end of the silicone wire. The phase transition temperature of the liquid crystal elastomer fiber is 75°C. The distance between the liquid crystal elastomer fiber and the silicone wire is 1200μm.

[0075] The liquid crystal elastomer fibers shrink when irradiated by the infrared laser and rebound after the infrared laser irradiation is removed;

[0076] The liquid crystal elastomer fiber is bonded to the serrated silicone film, with four bonding points spaced along the length of the liquid crystal elastomer fiber, one bonding point located at the left end of the liquid crystal elastomer fiber and the left front end of the serrated silicone film, and one bonding point located at the right end of the liquid crystal elastomer fiber and the right front end of the serrated silicone film;

[0077] When the liquid crystal elastomer fiber contracts, the serrated silicone film contracts accordingly; when the liquid crystal elastomer fiber rebounds, the serrated silicone film rebounds accordingly.

[0078] Example 2B

[0079] A method for preparing a photoactuator of Example 2A comprises the following specific steps:

[0080] (1) Prepare raw materials;

[0081] Pore formation line: diameter is 400 μm, number is 6;

[0082] Mold: Two serrated metal parts, the mold cavity thickness is 800μm, the shape of the mold cavity is a serrated line in the longitudinal section parallel to the left and right direction, and a straight line in the longitudinal section parallel to the front and back direction;

[0083] The first silica gel and the second silica gel: the refractive index of the first silica gel is higher than that of the second silica gel, and the difference between the refractive indices of the first silica gel and the second silica gel is 0.1;

[0084] Optical fiber: There are 6 of them, with the core, cladding, and coating arranged from the inside out. The coating at one end of the optical fiber is stripped off, leaving only the core and cladding as the insertion end. The length of the insertion end is 1.5 mm, and the diameter of the insertion end is 400 μm.

[0085] Liquid crystal elastomer fibers: The phase transition temperature is 75°C, the diameter is 500μm, and the number of fibers is 2. The contractile force of a single liquid crystal elastomer fiber is 0.02N. One end of a single liquid crystal elastomer fiber is fixed, and the other end is connected to a weight. An 808nm infrared laser is used to irradiate the liquid crystal elastomer fiber, which absorbs the laser energy and contracts. The illumination is stopped after 3 seconds, and the contraction process is recorded and analyzed using a high-speed camera. The change in the contraction amplitude of a single liquid crystal elastomer fiber after irradiation with 808nm infrared laser over time shows that the liquid crystal elastomer fiber responds quickly to light, meeting the response speed requirements for assisting cardiac contraction.

[0086] (2) adding a pore-forming line with the same shape and size as the silicone line into a mold cavity with the same shape and size as the serrated silicone membrane, pouring uncured first silicone into it, and then heating and curing, demolding, and extracting the pore-forming line in sequence to obtain a serrated silicone membrane with through holes;

[0087] (3) pouring uncured second silicone into the through holes of the serrated silicone membrane with through holes, and inserting an optical fiber into the rear end of each through hole with an insertion depth of 1.5 mm, heating and curing, and obtaining a semi-finished product consisting of a serrated silicone membrane, a silicone wire, and an optical fiber;

[0088] (4) Connect the liquid crystal elastomer fiber to the front end of the serrated silicone membrane to obtain a photoactuator.

[0089] The solid mechanics simulation module of Comsol Multiphysics was used to perform a precise 1:1 scale 3D model of the optical actuator. A contraction force of 0.04 N (equal to the sum of the contraction forces of two liquid crystal elastomer fibers) was applied to the serrated silicone membrane along the length direction of the liquid crystal elastomer fibers. The contraction amplitude of the serrated silicone membrane was calculated. Contraction amplitude = (deformation of the serrated silicone membrane along the force direction / original length of the serrated silicone membrane along the force direction) × 100%. The contraction amplitude of the serrated silicone membrane was 26%, as shown in Figure 2. Figure 6 shown.

[0090] Example 3A

[0091] A photoactuator is composed of a zigzag silicone film, silicone wire, optical fiber and liquid crystal elastomer fiber;

[0092] The serrated silicone membrane is arranged horizontally, with a longitudinal section parallel to the left-right direction being serrated and a longitudinal section parallel to the front-back direction being straight. The serrated silicone membrane is an integrally formed part with a thickness of 1000 μm.

[0093] There are four silicone wires, located inside the serrated silicone membrane, with no serrated silicone membrane blocking the front end. The silicone wires are one-piece molded parts with a diameter of 500μm.

[0094] The refractive index of the silicone wire is higher than that of the serrated silicone film; the difference in refractive index between the silicone wire and the serrated silicone film is 0.2;

[0095] The number of optical fibers is the same as that of silicone wires, and the two correspond one to one. The front end of the optical fiber is inserted into the back end of the corresponding silicone wire; the insertion depth of the front end of the optical fiber into the back end of the corresponding silicone wire is 2mm;

[0096] The liquid crystal elastomer fiber is in a straight state and is located in front of the silicone wire to receive the infrared laser emitted from the front end of the silicone wire. The phase transition temperature of the liquid crystal elastomer fiber is 90°C. The distance between the liquid crystal elastomer fiber and the silicone wire is 2000μm.

[0097] The liquid crystal elastomer fibers shrink when irradiated by the infrared laser and rebound after the infrared laser irradiation is removed;

[0098] The liquid crystal elastomer fiber is bonded to the serrated silicone film, with four bonding points spaced along the length of the liquid crystal elastomer fiber, one bonding point located at the left end of the liquid crystal elastomer fiber and the left front end of the serrated silicone film, and one bonding point located at the right end of the liquid crystal elastomer fiber and the right front end of the serrated silicone film;

[0099] When the liquid crystal elastomer fiber contracts, the serrated silicone film contracts accordingly; when the liquid crystal elastomer fiber rebounds, the serrated silicone film rebounds accordingly.

[0100] Example 3B

[0101] A method for preparing a photoactuator of Example 3A comprises the following specific steps:

[0102] (1) Prepare raw materials;

[0103] Pore formation line: diameter is 500 μm, number is 4;

[0104] Mold: Two serrated metal parts, the mold cavity thickness is 1000μm, the shape of the mold cavity is a serrated line in the longitudinal section parallel to the left and right direction, and a straight line in the longitudinal section parallel to the front and back direction;

[0105] The first silica gel and the second silica gel: the refractive index of the first silica gel is higher than that of the second silica gel, and the difference between the refractive indices of the first silica gel and the second silica gel is 0.2;

[0106] Optical fiber: There are 4 of them, and from the inside out they are the core, cladding, and coating. After the coating at one end of the optical fiber is stripped off, only the core and cladding are left as the insertion end. The length of the insertion end is 2mm and the diameter of the insertion end is 500μm.

[0107] Liquid crystal elastomer fibers: The phase transition temperature is 90°C, the diameter is 800μm, the number of fibers is 1, and the contractile force of a single liquid crystal elastomer fiber is 0.02N. One end of a single liquid crystal elastomer fiber is fixed, and a weight is connected to the other end. An 808nm infrared laser is used to irradiate the liquid crystal elastomer fiber, causing it to absorb the laser energy and contract. The irradiation is stopped after 3 seconds, and the contraction process is recorded and analyzed using a high-speed camera. The change in the contraction amplitude of a single liquid crystal elastomer fiber after irradiation with the 808nm infrared laser over time indicates that the liquid crystal elastomer fiber responds quickly to light, meeting the response speed requirements for assisting cardiac contraction.

[0108] (2) adding a pore-forming line with the same shape and size as the silicone line into a mold cavity with the same shape and size as the serrated silicone membrane, pouring uncured first silicone into it, and then heating and curing, demolding, and extracting the pore-forming line in sequence to obtain a serrated silicone membrane with through holes;

[0109] (3) pouring uncured second silicone into the through holes of the serrated silicone membrane with through holes, and inserting an optical fiber into the rear end of each through hole to a depth of 2 mm, and heating and curing to obtain a semi-finished product consisting of a serrated silicone membrane, a silicone wire, and an optical fiber;

[0110] (4) Connect the liquid crystal elastomer fiber to the front end of the serrated silicone membrane to obtain a photoactuator.

[0111] The solid mechanics simulation module of Comsol Multiphysics was used to perform a precise 1:1 scale 3D model of the optical actuator. A contraction force of 0.02 N (equal to the contraction force of one liquid crystal elastomer fiber) was applied to the serrated silicone membrane along the length direction of the liquid crystal elastomer fiber. The contraction amplitude of the serrated silicone membrane was calculated. Contraction amplitude = (deformation of the serrated silicone membrane along the force direction / original length of the serrated silicone membrane along the force direction) × 100%. The contraction amplitude of the serrated silicone membrane was 12.5%, as shown in Figure 2. Figure 6 shown.

Claims

1. A light actuator, characterized in that: It includes a serrated silicone film (2), a silicone wire (4), an optical fiber (3) and a liquid crystal elastomer fiber (1); The serrated silicone membrane (2) is arranged horizontally, and the longitudinal section parallel to the left-right direction is in a serrated line shape, and the longitudinal section parallel to the front-back direction is in a straight line shape; There are multiple silicone wires (4), which are located inside the serrated silicone film (2), and the front end is not blocked by the serrated silicone film (2); The refractive index of the silicone wire (4) is higher than that of the sawtooth silicone film (2); The number of optical fibers (3) is the same as that of silicone wires (4), and the two correspond one to one, and the front end of the optical fiber (3) is inserted into the rear end of the corresponding silicone wire (4); The liquid crystal elastomer fiber (1) is in a straightened state and is located in front of the silicone wire (4) and is used to receive the infrared laser emitted from the front end of the silicone wire (4); The liquid crystal elastomer fiber (1) shrinks when irradiated by the infrared laser and rebounds after the infrared laser irradiation is removed; The liquid crystal elastomer fiber (1) is connected to the sawtooth silicone film (2), and the connection method satisfies: when the liquid crystal elastomer fiber (1) contracts, the sawtooth silicone film (2) contracts accordingly; when the liquid crystal elastomer fiber (1) rebounds, the sawtooth silicone film (2) rebounds accordingly.

2. The optical actuator according to claim 1, wherein: The difference in refractive index between the silicone wire (4) and the sawtooth silicone film (2) is 0.05-0.

2.

3. The optical actuator according to claim 1, wherein: The serrated silicone membrane (2) is an integrally formed part with a thickness of 100-1000 μm.

4. The optical actuator according to claim 3, wherein: The silicone wire (4) is an integrally formed part with a diameter of 50-500 μm.

5. The optical actuator according to claim 3, wherein: The insertion depth of the front end of the optical fiber (3) into the rear end of the corresponding silicone wire (4) is 1-2 mm.

6. The optical actuator according to claim 1, wherein: The phase transition temperature of the liquid crystal elastomer fiber (1) is 60-90°C.

7. The optical actuator according to claim 1, wherein: The distance between the liquid crystal elastomer fiber (1) and the silicone wire (4) is 500-2000 μm.

8. The optical actuator according to claim 1, wherein: The liquid crystal elastomer fiber (1) is bonded to the serrated silicone film (2), and the number of bonding points is more than two and is arranged at intervals along the length direction of the liquid crystal elastomer fiber (1), wherein one bonding point is located at the left end of the liquid crystal elastomer fiber (1) and the left front end of the serrated silicone film (2), and one bonding point is located at the right end of the liquid crystal elastomer fiber (1) and the right front end of the serrated silicone film (2).

9. A method for preparing a photoactuator according to any one of claims 1 to 8, characterized in that: The following steps are involved: (a) adding a pore-forming wire having the same shape and size as the silicone wire into a mold cavity having the same shape and size as the serrated silicone membrane, pouring uncured first silicone into the mold cavity, and then heating and curing, demolding, and extracting the pore-forming wire in sequence to obtain a serrated silicone membrane with through holes; (b) pouring uncured second silicone into the through holes of the serrated silicone membrane with through holes, inserting an optical fiber into the rear end of each through hole, and then heating and curing the resultant product to obtain a semi-finished product consisting of the serrated silicone membrane, the silicone wire, and the optical fiber; (c) The liquid crystal elastomer fiber is connected to the front end of the serrated silicone membrane to obtain a photoactuator.

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