Light actuator and preparation method thereof

Abstract

The invention belongs to the technical field of cardiac contraction auxiliary devices, and relates to a light actuator and a preparation method thereof. The optical actuator comprises a sawtooth silica gel film, a silica gel line, an optical fiber and a liquid crystal elastomer fiber. The preparation method comprises the following steps: (a) adding a pore-forming line with the same shape and size as a silica gel line into a mold cavity with the same shape and size as a sawtooth silica gel film, pouring uncured first silica gel into the mold cavity, and sequentially carrying out heating curing, demolding and pore-forming line extraction to obtain a sawtooth silica gel film with through holes; (b) pouring uncured second silica gel into the through holes of the sawtooth silica gel membrane with the through holes, inserting an optical fiber into the rear end of each through hole, and heating and curing to obtain a semi-finished product consisting of the sawtooth silica gel membrane, the silica gel line and the optical fibers; and (c) connecting the liquid crystal elastomer fiber with the front end of the sawtooth silica gel film to obtain the light actuator. The light actuator can be aligned with the ventricular contraction frequency and time, and the requirement for assisting in cardiac contraction is met.

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 weakened myocardial contractility, and the heart is unable to effectively pump enough blood to the whole body. Cardiac contraction assist devices can externally apply an auxiliary force to enhance the squeezing force during heart contraction, significantly increase the stroke volume of the heart, ensure that all organs of the body receive sufficient blood supply, and relieve a series of symptoms caused by insufficient blood supply, such as fatigue, dyspnea, etc. For a damaged heart, the cardiac contraction assist device shares part of the blood pumping work, reduces the resistance that the heart itself needs to overcome, and reduces the energy consumed by the heart in maintaining blood circulation, which helps the myocardium to recover and repair to a certain extent and delays the further deterioration of heart function. Therefore, studying cardiac contraction assist devices is of great significance.

[0003] Patent CN115869531B discloses an implantable ventricular assist mechanical contraction device, which includes a telescopic sleeve for surrounding the whole heart, a main system processing mechanism, a pressure monitoring sensing component and an energy component. The pressure monitoring sensing component is installed on the arterial blood vessel wall of the heart and is electrically connected to the main system processing mechanism. The main system processing mechanism is electrically connected to the telescopic sleeve, and the energy component is electrically connected to the main system processing mechanism. The telescopic sleeve is mainly composed of a plurality of knuckle structures connected to each other. The knuckle structure includes a proximal end and a distal end. The knuckle structure expands when powered off and radially rotates and squeezes the heart in the direction from the proximal end to the distal end when powered on. It has the effect of assisting the heart to contract in a direction consistent with the normal physiological contraction mode of completely simulating ventricular muscle, thereby improving the hemodynamic effect of each heart contraction and pumping blood, and reducing the degree of damage of the ventricular assist contraction device to the heart.

[0004] Patent application CN117442867A discloses a cardiac contraction assist device and its control method. The cardiac contraction assist device includes: an opening cover, which includes a first cavity, a second cavity and a third cavity formed in sequence from the inside out. One end of the first cavity is open and is used to accommodate the heart. Both the second cavity and the first cavity can be deformed. The third cavity is a cavity with limited space, and the third cavity is connected to the second cavity; a driving electrode pair is arranged in the third cavity and is used to generate an electrostatic attraction force that drives the distance between them to decrease when the power supply device is connected; a deformable cavity is suitable for accommodating a flowable target medium, including a first section and a second section; the first section is located in the second cavity, and the second section is located in the third cavity and at least partially distributed between the driving electrode pairs; the first section drives the second cavity and the first cavity to deform towards or away from the heart in response to the volume change of the second section. This device assists in the contraction of different regions of the heart and has good safety.

[0005] The above cardiac assist devices are all electro - actuators. However, the electric field distribution of electro - actuators is relatively diffuse, making it difficult to focus on an extremely small area, unable to precisely control the actuation of specific tiny parts, and having a low spatial resolution. For some electro - actuators, such as those based on electro - thermal effects, due to the delay in heat transfer, the response speed is low. In biomedical implant applications, electro - actuators have potential risks. For example, electrical signals may trigger electrolysis and electrochemical reactions, leading to electrode corrosion. The metal ions or other products generated may be toxic to biological tissues, causing inflammation or immune reactions. Electro - actuators may also generate electromagnetic interference during operation, affecting the normal operation of other surrounding electronic devices. In some special environments, such as the magnetic resonance imaging room in a hospital, electromagnetic interference may cause serious consequences. Therefore, due to the low spatial resolution, low response speed, and potential risks, the application of electro - actuators will be further restricted.

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

[0007] The object of the present invention is to solve the above - mentioned problems existing in the prior art and provide a photo - actuator and its preparation method.

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

[0009] A photo - actuator includes a serrated silicone film, silicone wires, optical fibers, and liquid crystal elastomer fibers;

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

[0011] The number of silicone wires is multiple, located inside the serrated silicone film, and the front ends are not blocked by the serrated silicone film;

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

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

[0014] The liquid crystal elastomer fibers are in a straight state, located in front of the silicone wires, and are used to receive the infrared laser emitted from the front ends of the silicone wires;

[0015] When the liquid crystal elastomer fibers are irradiated by the infrared laser, they contract, and when the infrared laser irradiation is removed, they rebound;

[0016] The liquid crystal elastomer fibers are connected to the serrated silicone film, and the connection method satisfies that when the liquid crystal elastomer fibers contract, the serrated silicone film contracts accordingly; when the liquid crystal elastomer fibers rebound, the serrated silicone film rebounds accordingly.

[0017] An optical waveguide is a structure or medium that can guide the propagation of light waves. An optical waveguide generally includes a core layer and a cladding layer, and its principle is based on the total internal reflection principle of light. When light travels from a medium with a high refractive index to a medium with a low refractive index, at a certain incident angle, the light will undergo total internal reflection at the interface of the two media, and thus be confined to the core layer with a high refractive index for long-distance transmission with only a small amount of loss.

[0018] In the present invention, due to the fact that "the number of silica gel wires is multiple and they are located inside the serrated silica gel film" and "the refractive index of the silica gel wires is higher than that of the serrated silica gel film", the serrated silica gel film and the silica gel wires together constitute an optical waveguide, where the serrated silica gel film is the cladding layer of the optical waveguide and the silica gel wires are the core layer of the optical waveguide.

[0019] In the present invention, due to the fact that "the front end of the optical fiber is inserted into the rear end of the corresponding silica gel wire", after all the optical fibers are uniformly connected to an 808 nm infrared laser, the infrared laser will be transmitted along the optical fiber, exit from the front end of the optical fiber, and be coupled into the silica gel wire, and then be transmitted along the silica gel wire in the form of total internal reflection. Due to the fact that "the front end of the silica gel wire is not blocked by the serrated silica gel film" and "the liquid crystal elastomer fiber is in a straight state and is located in front of the silica gel wire to receive the light exiting from the front end of the silica gel wire", the infrared laser will exit from the front end of the silica gel wire and shine on the liquid crystal elastomer fiber. When the liquid crystal elastomer fiber receives the infrared laser, it will absorb the energy of the infrared laser and the temperature will rise. When its temperature exceeds the phase transition temperature, it will contract. When the infrared laser is turned off, it will dissipate heat and the temperature will drop below the transition temperature and it will rebound. Due to the fact that "the serrated silica gel film is horizontally arranged, the longitudinal section parallel to the left-right direction is serrated, and the longitudinal section parallel to the front-back direction is linear" and "the liquid crystal elastomer fiber is connected to the serrated silica gel film and the connection method satisfies that when the liquid crystal elastomer fiber contracts, the serrated silica gel film contracts accordingly; when the liquid crystal elastomer rebounds, the serrated silica gel film rebounds accordingly", when the liquid crystal elastomer fiber contracts, the serrated silica gel film contracts accordingly; when the liquid crystal elastomer rebounds, the serrated silica gel film rebounds accordingly.

[0020] Currently, most cardiac contraction assist devices are overall assist contraction devices. Such overall assist contraction devices wrap all or most of the surface of the heart to achieve comprehensive assistance for cardiac contraction.

[0021] However, the above overall assist contraction devices have the following disadvantages:

[0022] (1) The atria and ventricles of the heart have a strict and asynchronous rhythm of contraction and relaxation. The atria contract first, squeezing blood into the ventricles, and then the ventricles contract, pumping blood out of the heart. The overall auxiliary contraction device cannot distinguish the different contraction times of the atria and ventricles, and the auxiliary contraction may cause the contraction sequence of the atria and ventricles to be chaotic, which will not only damage the normal blood pumping function of the heart, but also may cause blood backflow, increase the internal pressure of the heart, and reduce the overall blood pumping efficiency of the heart.

[0023] (2) The rhythm of the heart is regulated by various factors, including the autonomic nervous system and the heart's own electrophysiological mechanism. The overall auxiliary contraction may interfere with the normal heart rate regulation mechanism of the heart, making it difficult for the heart to make appropriate heart rate adjustments under different physiological states (such as rest, exercise), hindering the heart's own heart rate regulation function, and the heart cannot adapt to various activity states of the body.

[0024] The serrated silicone membrane of the photoactuator of the present invention can be sutured on the ventricle. By controlling the opening and closing of the infrared laser, the frequency and timing of the contraction and rebound of the photoactuator can be controlled, and it can be aligned with the frequency and timing of the ventricle contraction, achieving the effect of assisting the ventricle contraction. The photoactuator of the present invention can specifically assist the ventricle contraction, overcoming the defect that the traditional auxiliary ventricle contraction device cannot specifically act on the ventricle, avoiding the problems that may be caused by the simultaneous contraction of the ventricle and atrium, and has important significance for the treatment of myocardial infarction.

[0025] As a preferred technical solution:

[0026] For a photoactuator as described above, the difference in refractive index between the silicone wire and the serrated silicone membrane is 0.05 - 0.2.

[0027] For a photoactuator as described above, the serrated silicone membrane is an integrally formed part with a thickness of 100 - 1000 μm. In this way, it is not only convenient for processing and forming, but also can avoid the deterioration of the contraction effect due to excessive thickness; the length and width of the serrated silicone membrane are both related to the size of the atrium / ventricle.

[0028] For a photoactuator as described above, the silicone wire is an integrally formed part with a diameter of 50 - 500 μm. In this way, it is not only convenient for processing and forming, but also can avoid the deterioration of the contraction effect due to excessive 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] For a photoactuator as 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. In this way, it can not only avoid the poor flexibility of the photoactuator caused by excessive insertion depth, but also avoid the insecure connection and easy disconnection caused by too small insertion depth.

[0030] 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 amplitude 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, and if the phase transition temperature is too low and the difference from the body environment temperature is too small, the cooling time becomes longer and the rebound becomes slower.

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

[0032] A photoactuator as described above, the liquid crystal elastomer fiber is bonded to the serrated silicone film, and the number of bonding points is more than 2 and 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, including the following steps:

[0034] (a) Add a pore-forming wire with the same shape and size as the silicone wire into the mold cavity with the same shape and size as the serrated silicone film. After pouring uncured first silicone into it, perform heating and curing, demolding, and extracting the pore-forming wire in sequence to obtain a serrated silicone film with through holes;

[0035] (b) Pour uncured second silicone into the through holes of the serrated silicone film with through holes, and at the same time insert an optical fiber at the rear end of each through hole, and then perform heating and curing to obtain a semi-finished product composed of a serrated silicone film, a silicone wire, and an optical fiber;

[0036] (c) Connect the liquid crystal elastomer fiber to the front end of the serrated silicone film to obtain the photoactuator.

[0037] Beneficial effects:

[0038] (1) The photoactuator of the present invention realizes the control of the frequency and timing of the contraction and rebound of the photoactuator by controlling the opening and closing of the mid-infrared laser in the optical fiber, and can align with the frequency and timing of ventricular contraction, playing an auxiliary role in ventricular contraction.

[0039] (2) Compared with the electroactuator of the prior art, the photoactuator of the present invention has higher spatial resolution by virtue of the high focusing characteristics of light; the photoactuator uses light as the energy source, has better biocompatibility, and has little adverse effect on the surrounding biological tissues; the light signal propagation speed is extremely fast, and the material in the photoactuator responds quickly to light and can complete the action in about 250 milliseconds. Description of the drawings

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

[0041] Figures 2 to 4 They are views of the photo - actuator of the present invention from different angles;

[0042] Figure 5 It is a graph showing the change of the contraction amplitude of a single liquid - crystal elastomer fiber used in the photo - actuator of Embodiment 1B of the present invention over time after irradiating with an 808 - nm infrared laser;

[0043] Figure 6 They are the simulation test results of the contraction amplitude of the photo - actuator of the present invention;

[0044] In the figure, 1 is a liquid - crystal elastomer fiber, 2 is a serrated silica gel film, 3 is an optical fiber, and 4 is a silica gel wire. Detailed implementation manners

[0045] The present invention will be further described below in conjunction with specific implementation manners. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it 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 also fall within the scope defined by the appended claims of this application.

[0046] Embodiment 1A

[0047] As Figure 1 , Figure 2 , Figure 3 and Figure 4 shown, a photo - actuator is composed of a serrated silica gel film 2, a silica gel wire 4, an optical fiber 3, and a liquid - crystal elastomer fiber 1;

[0048] The serrated silica gel film 2 is horizontally arranged, and its longitudinal section parallel to the left - right direction is serrated, and its longitudinal section parallel to the front - back direction is linear; the serrated silica gel film 2 is an integrally formed part with a thickness of 100 μm;

[0049] The number of silica gel wires 4 is 8, which are located inside the serrated silica gel film 2 and the front ends are not blocked by the serrated silica gel film 2; the silica gel wire 4 is an integrally formed part with a diameter of 50 μm;

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

[0051] The number of optical fibers 3 is the same as that of the silica gel wires 4, and they correspond one by one. The front end of the optical fiber 3 is inserted into the rear end of the corresponding silica gel wire 4; the insertion depth of the front end of the optical fiber 3 in the rear end of the corresponding silica gel 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, and is used 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] When the liquid crystal elastomer fiber 1 is irradiated with the infrared laser, it contracts, and rebounds after the infrared laser irradiation is removed;

[0054] The liquid crystal elastomer fiber 1 is bonded to the serrated silicone film 2, and the number of bonding points is 4 and they are arranged at intervals along the length direction of the liquid crystal elastomer fiber 1, wherein 1 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 1 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 film 2 contracts accordingly; when the liquid crystal elastomer fiber 1 rebounds, the serrated silicone film 2 rebounds accordingly.

[0056] Example 1B

[0057] A method for preparing a photoactuator of Example 1A, the specific steps are as follows:

[0058] (1) Prepare raw materials;

[0059] Pore-forming wire: The diameter is 50 μm and the number is 8;

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

[0061] First silicone and second silicone: The refractive index of the first silicone is higher than that of the second silicone, and the difference in their refractive indices is 0.05;

[0062] Optical fiber: The number is 8, which consists of a core, a cladding and a coating layer from the inside out. After the coating layer at one end of the optical fiber is peeled off, only the core and the cladding are left as the insertion end for standby. The length of the insertion end is 1 mm and the diameter of the insertion end is 50 μm;

[0063] Liquid crystal elastomer fiber: The phase transition temperature is 60 °C, the diameter is 200 μm, the number is 3, and the contraction force of a single liquid crystal elastomer fiber is 0.02 N; Fix one end of a single liquid crystal elastomer fiber, connect a weight to the other end, irradiate the liquid crystal elastomer fiber with an 808 nm infrared laser, it absorbs the laser energy, contracts, and stops the light irradiation at 3 seconds. Use a high-speed camera to record and analyze its contraction process. The change of the contraction amplitude of a single liquid crystal elastomer fiber with time after irradiating with an 808 nm infrared laser is as Figure 5As shown, it shows that 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) Add a pore-forming wire with the same shape and size as the silica gel wire into the mold cavity with the same shape and size as the serrated silica gel membrane. After pouring the uncured first silica gel into it, perform heating and curing, demolding, and extract the pore-forming wire in sequence to obtain a serrated silica gel membrane with through holes;

[0065] (3) Pour the uncured second silica gel into the through holes of the serrated silica gel membrane with through holes. At the same time, insert an optical fiber into the rear end of each through hole with an insertion depth of 1 mm, and perform heating and curing to obtain a semi-finished product composed of a serrated silica gel membrane, a silica gel wire, and an optical fiber;

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

[0067] Using the solid mechanics simulation module of Comsol Multiphysics, perform precise 3D modeling of the photoactuator at a 1:1 ratio. Then, apply a contraction force of 0.06 N (equal to the sum of the contraction forces of 3 liquid crystal elastomer fibers) to the serrated silica gel membrane along the length direction of the liquid crystal elastomer fiber, and calculate the contraction amplitude of the serrated silica gel membrane. The contraction amplitude = (the deformation of the serrated silica gel membrane along the force application direction / the original length of the serrated silica gel membrane along the force application direction) × 100%. The contraction amplitude of the serrated silica gel membrane is 41%, as Figure 6 shown.

[0068] Example 2A

[0069] A photoactuator is composed of a serrated silica gel membrane, a silica gel wire, an optical fiber, and a liquid crystal elastomer fiber;

[0070] The serrated silica gel membrane is arranged horizontally, and its longitudinal section parallel to the left-right direction is serrated, and its longitudinal section parallel to the front-back direction is linear; the serrated silica gel membrane is an integrally formed part with a thickness of 800 μm;

[0071] The number of silica gel wires is 6, which are located inside the serrated silica gel membrane and the front ends are not blocked by the serrated silica gel membrane; the silica gel wire is an integrally formed part with a diameter of 400 μm;

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

[0073] The number of optical fibers is the same as that of the silica gel wires, and they correspond one by one. The front end of the optical fiber is inserted into the rear end of the corresponding silica gel wire; the insertion depth of the front end of the optical fiber in the rear end of the corresponding silica gel wire is 1.5 mm;

[0074] 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; 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 1200 μm;

[0075] When the liquid crystal elastomer fiber is irradiated by the infrared laser, it contracts and rebounds after the infrared laser irradiation is removed;

[0076] The liquid crystal elastomer fiber is bonded to the serrated silicone film, and the number of bonding points is 4 and they are arranged at intervals along the length direction of the liquid crystal elastomer fiber. Among them, 1 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 1 bonding point is 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 is as follows:

[0080] (1) Prepare raw materials;

[0081] Hole-making wire: The diameter is 400 μm and the number is 6;

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

[0083] The first silicone and the second silicone: The refractive index of the first silicone is higher than that of the second silicone, and the difference in their refractive indices is 0.1;

[0084] Optical fiber: The number is 6, which consists of a core, a cladding and a coating layer from the inside out. After the coating layer at one end of the optical fiber is peeled off, only the core and the cladding are left as the insertion end for standby. The length of the insertion end is 1.5 mm and the diameter of the insertion end is 400 μm;

[0085] Liquid crystal elastomer fiber: The phase transition temperature is 75 °C, the diameter is 500 μm, the number is 2, and the contraction force of a single liquid crystal elastomer fiber is 0.02 N; Fix one end of a single liquid crystal elastomer fiber, connect a weight to the other end, and irradiate the liquid crystal elastomer fiber with 808 nm infrared laser. It absorbs the laser energy, contracts, and stops irradiating the light at 3 seconds. Use a high-speed camera to record and analyze its contraction process. The change of the contraction amplitude of a single liquid crystal elastomer fiber with time after irradiating with 808 nm infrared laser shows that the liquid crystal elastomer fiber responds quickly to light and meets the response speed requirements for assisting heart contraction;

[0086] (2) Add a pore-forming wire with the same shape and size as the silica gel wire into the mold cavity with the same shape and size as the serrated silica gel membrane. After pouring the uncured first silica gel into it, perform heat curing, demolding, and extract the pore-forming wire in sequence to obtain a serrated silica gel membrane with through holes;

[0087] (3) Pour the uncured second silica gel into the through holes of the serrated silica gel membrane with through holes. At the same time, insert an optical fiber into the rear end of each through hole, with an insertion depth of 1.5 mm, and perform heat curing to obtain a semi-finished product composed of a serrated silica gel membrane, a silica gel wire, and an optical fiber;

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

[0089] Using the solid mechanics simulation module of Comsol Multiphysics, perform precise 3D modeling of the photoactuator at a 1:1 ratio. Then apply a contraction force of 0.04 N (equal to the sum of the contraction forces of 2 liquid crystal elastomer fibers) to the serrated silica gel membrane along the length direction of the liquid crystal elastomer fiber, and calculate the contraction amplitude of the serrated silica gel membrane. The contraction amplitude = (the deformation of the serrated silica gel membrane along the force application direction / the original length of the serrated silica gel membrane along the force application direction) × 100%. The contraction amplitude of the serrated silica gel membrane is 26%, as Figure 6 shown.

[0090] Example 3A

[0091] A photoactuator is composed of a serrated silica gel membrane, a silica gel wire, an optical fiber, and a liquid crystal elastomer fiber;

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

[0093] The number of silica gel wires is 4, located inside the serrated silica gel membrane, and there is no serrated silica gel membrane blocking at the front end; The silica gel wire is an integrally formed part with a diameter of 500 μm;

[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 the silicone wires, and they are in one-to-one correspondence. The front end of the optical fiber is inserted into the rear end of the corresponding silicone wire; the insertion depth of the front end of the optical fiber into the rear end of the corresponding silicone wire is 2 mm;

[0096] 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; the phase change temperature of the liquid crystal elastomer fiber is 90 °C; the distance between the liquid crystal elastomer fiber and the silicone wire is 2000 μm;

[0097] When the liquid crystal elastomer fiber is irradiated by the infrared laser, it shrinks, and rebounds after the infrared laser irradiation is removed;

[0098] The liquid crystal elastomer fiber is bonded to the serrated silicone film. The number of bonding points is 4 and they are arranged at intervals along the length direction of the liquid crystal elastomer fiber. Among them, 1 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 1 bonding point is 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 shrinks, the serrated silicone film shrinks 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 is as follows:

[0102] (1) Prepare raw materials;

[0103] Hole-making wire: The diameter is 500 μm and the number is 4;

[0104] Mold: Two serrated metal parts. The thickness of the mold cavity is 1000 μm. The shape of the mold cavity is serrated in the longitudinal section parallel to the left-right direction and linear in the longitudinal section parallel to the front-back direction;

[0105] The first silicone and the second silicone: The refractive index of the first silicone is higher than that of the second silicone, and the difference in refractive index between the two is 0.2;

[0106] Optical fiber: The number is 4. From the inside to the outside, there are a core, a cladding, and a coating layer in sequence. After the coating layer at one end of the optical fiber is peeled off, only the core and the cladding are left as the insertion end for standby. The length of the insertion end is 2 mm and the diameter of the insertion end is 500 μm;

[0107] Liquid crystal elastomer fiber: The phase transition temperature is 90 °C, the diameter is 800 μm, the number is 1, and the contraction force of a single liquid crystal elastomer fiber is 0.02 N. Fix one end of a single liquid crystal elastomer fiber, connect a weight to the other end, and irradiate the liquid crystal elastomer fiber with 808 nm infrared laser. It absorbs the laser energy, contracts, and stops the light irradiation at 3 seconds. Use a high-speed camera to record and analyze its contraction process. The variation of the contraction amplitude of a single liquid crystal elastomer fiber with time after irradiating with 808 nm infrared laser shows that the liquid crystal elastomer fiber responds rapidly to light, meeting the response speed requirement for assisting heart contraction;

[0108] (2) Insert a pore-forming wire with the same shape and size as the silicone wire into the mold cavity with the same shape and size as the serrated silicone membrane. After pouring the uncured first silicone into it, perform heat curing, demolding, and extract the pore-forming wire in sequence to obtain a serrated silicone membrane with through holes;

[0109] (3) Pour the uncured second silicone into the through holes of the serrated silicone membrane with through holes. At the same time, insert an optical fiber into the back end of each through hole with an insertion depth of 2 mm, and perform heat curing to obtain a semi-finished product composed 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 the photoactuator.

[0111] Using the solid mechanics simulation module of Comsol Multiphysics, perform precise 3D modeling of the photoactuator at a 1:1 ratio. Then apply a contraction force of 0.02 N (equal to the contraction force of 1 liquid crystal elastomer fiber) to the serrated silicone membrane along the length direction of the liquid crystal elastomer fiber, and calculate the contraction amplitude of the serrated silicone membrane. The contraction amplitude = (the deformation of the serrated silicone membrane along the force application direction / the original length of the serrated silicone membrane along the force application direction) × 100%. The contraction amplitude of the serrated silicone membrane is 12.5%, as Figure 6 shown.

Claims

1. A photoactuator, characterized in that, It includes a serrated silicone film (2), silicone wires (4), optical fibers (3), and liquid crystal elastomer fibers (1); The serrated silicone film (2) is horizontally arranged, with a serrated linear shape in the longitudinal section parallel to the left - right direction and a linear shape in the longitudinal section parallel to the front - back direction; The number of silicone wires (4) is multiple. They are located inside the serrated silicone film (2), and the front ends are not blocked by the serrated silicone film (2); The refractive index of the silicone wire (4) is higher than that of the serrated silicone film (2); The number of optical fibers (3) is the same as that of the silicone wires (4), and they correspond one by one. 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 straight 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 serrated silicone film (2) in a connection manner that satisfies: when the liquid crystal elastomer fiber (1) shrinks, the serrated silicone film (2) shrinks accordingly; when the liquid crystal elastomer fiber (1) rebounds, the serrated silicone film (2) rebounds accordingly.

2. The opto-actuator according to claim 1, characterized in that, The difference in refractive index between the silicone wire (4) and the serrated silicone film (2) is 0.05 - 0.

2.

3. The optical actuator according to claim 1, characterized in that, The serrated silicone film (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 opto-actuator according to claim 1, characterized in that, The phase transition temperature of the liquid crystal elastomer fiber (1) is 60 - 90 °C.

7. A photoactuator according to claim 1, characterized in that, The distance between the liquid crystal elastomer fiber (1) and the silicone wire (4) is 500 - 2000 μm.

8. A photoactuator according to claim 1, characterized in that, The liquid crystal elastomer fiber (1) is bonded to the serrated silicone film (2). 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 (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).

9. A method for preparing a photoactuator according to any one of claims 1 to 8, characterized in that, It includes the following steps: (a) Add a pore - forming wire with the same shape and size as the silicone wire into the mold cavity with the same shape and size as the serrated silicone film. After pouring uncured first silicone into it, heat - cure, demold, and extract the pore - forming wire in sequence to obtain a serrated silicone film with through - holes; (b) Pour uncured second silicone into the through - holes of the serrated silicone film with through - holes. At the same time, insert an optical fiber into the rear end of each through - hole, and then heat - cure to obtain a semi - finished product composed of a serrated silicone film, silicone wires, and optical fibers; (c) Connect the liquid crystal elastomer fiber to the front end of the serrated silicone film to obtain the photo - actuator.

Images