A device for testing the performance of a thermally induced shape memory polymer

Abstract

The utility model discloses a kind of thermal type shape memory polymer performance testing devices, it includes: test container, it is suitable for by heating refrigerating device control internal temperature;Clamping assembly, it is installed in test container, and including first clamp and second clamp being set in first direction opposite direction;First clamp, second clamp are used to clamp thermal type shape memory polymer;Adjustment assembly, it is installed in test container, and including the screw rod of transmission connection with clamping assembly;Screw rod is suitable for rotating around the first axis of first direction relative to test container, to drive first clamp, second clamp mutually close or mutually far away along first direction;And ranging component, it includes the angle encoder of coaxial connection with screw rod, angle encoder is used to measure the rotation angle of screw rod, to calculate the relative displacement amount of first clamp, second clamp in clamping assembly based on the rotation angle and the pitch of screw rod. Using the test device can improve the performance test operation of thermal type shape memory polymer is cumbersome, and the problem of poor displacement precision control.

Description

Technical Field

[0001] This utility model relates to the field of performance testing of thermotropic shape memory polymers, and specifically to a performance testing device for thermotropic shape memory polymers. Background Technology

[0002] Thermotropic shape memory polymers are smart materials capable of recovering their shape under applied temperature stimulation. Due to their unique shape memory effect, they exhibit significant application value in cutting-edge fields such as biomedicine, aerospace, and flexible electronics. Shape retention rate and shape recovery rate are core indicators for evaluating their performance; therefore, accurate and reliable measurement of these properties is crucial for material research and development, quality control, and application. Currently, performance testing of these polymers generally relies on manual operation or general-purpose material testing machines. Manual stretching makes precise control of displacement difficult, while general-purpose material testing machines, although powerful, are not optimized for the specific testing procedures of shape memory polymers, resulting in complex operation procedures, and their mechanical loading modes are not specifically designed for the precise quantification of the shape memory effect. In summary, existing technologies for performance testing of thermotropic shape memory polymers still suffer from cumbersome operation and poor displacement accuracy control. Utility Model Content

[0003] The purpose of this invention is to overcome the aforementioned defects or problems in the background technology and to provide a performance testing device for thermotropic shape memory polymers, which can improve the problems of cumbersome operation and poor displacement accuracy control in the performance testing of thermotropic shape memory polymers, or provide a material basis for improving these problems.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] Technical Solution 1: A performance testing device for thermotropic shape memory polymers, comprising: a test container adapted to control its internal temperature via a heating and cooling device; a clamping assembly installed in the test container, including a first clamp and a second clamp arranged opposite to each other along a first direction; the first clamp and the second clamp being used to clamp the thermotropic shape memory polymer; an adjustment assembly installed in the test container, including a screw tractor throttlely connected to the clamping assembly; the screw being adapted to rotate relative to the test container about a first axis in the first direction, thereby causing the first clamp and the second clamp to move closer to or further away from each other along the first direction; and a ranging assembly including an angle encoder coaxially connected to the screw, the angle encoder being used to measure the rotation angle of the screw, thereby calculating the relative displacement of the first clamp and the second clamp in the clamping assembly based on the rotation angle and the screw pitch.

[0006] Technical Solution 2 based on Technical Solution 1: In the clamping assembly, the position of the second clamp is fixed relative to the test container; the screw is connected to the first clamp in a transmission manner and is adapted to drive the first clamp to move along a first direction.

[0007] Technical solution three based on technical solution two: The adjustment component further includes a slide bar extending along a first direction and fixed relative to the test container; the first clamp is slidably connected to the slide bar along the first direction and is anti-rotationally engaged with the slide bar relative to the first axis.

[0008] Technical solution four based on technical solution three: The number of sliding rods is two, which are arranged on both sides of the first clamp along a second direction perpendicular to the first direction.

[0009] Based on technical solution three or four, technical solution five: the slide bar is provided with a scale along the first direction.

[0010] Technical solution six based on technical solution five: The first clamp includes a slider and a first clamping head fixedly connected to each other; the slider and the screw are threadedly connected in a first direction; the first clamping head is used to clamp the thermotropic shape memory polymer.

[0011] Technical solution seven based on technical solution six: The second clamp includes a base and a second clamping head that are fixedly connected to each other; the base is fixed to the test container; the clamping surfaces of the first clamping head and the second clamping head for clamping the thermotropic shape memory polymer are made of rubber and have anti-slip textures.

[0012] Technical solution eight based on technical solution seven: The adjustment component further includes a support; the support is fixed to the test container and located at the other end relative to the base along a first direction; both ends of the screw are rotatably mounted on the support and the base; both ends of the slide rod are mounted on the support and the base; the angle encoder is mounted on the support or the base.

[0013] Technical Solution Nine based on Technical Solution One: The adjustment component further includes a crank handle located outside the test container and coaxially connected to the screw, the crank handle being used to drive the screw to rotate.

[0014] Technical Solution 10 based on Technical Solution 1: The test container is equipped with a temperature sensor and a temperature control unit; the temperature sensor is adapted to detect the internal temperature of the test container; the temperature control unit is adapted to control the temperature inside the test container through the heating and cooling device according to the signal transmitted by the temperature sensor.

[0015] As can be seen from the above description of this utility model, compared with the prior art, this utility model has the following beneficial effects:

[0016] Technical Solution 1 provides a performance testing device for thermotropic shape memory polymers, comprising a test container, a clamping assembly, an adjustment assembly, and a ranging assembly. Through the cooperation of these components, high-precision and high-reliability testing of the thermotropic shape memory polymer's performance is achieved. The test container, through a heating and cooling system, precisely controls the internal temperature, providing a stable and adaptable environment for polymer performance testing. The clamping and adjustment assemblies are integrated within the test container; this integrated design allows the entire process of sample stretching deformation and shape recovery to be completed within a stable and precise temperature field, avoiding temperature fluctuations and operational errors introduced by transferring samples between heating and measuring equipment in existing technologies. The clamping assembly conveniently clamps and fixes the polymer. The clamping assembly and the adjustment assembly are connected by a screw drive, which converts rotational operations into displacement of the clamping assembly. An angle encoder is incorporated; by acquiring the encoder's electrical signal and combining it with the screw pitch, the real-time displacement of the clamp can be accurately calculated, improving upon the poor accuracy control of manual displacement in existing technologies. Furthermore, when conducting performance tests, the polymer can be easily obtained by simply clamping it onto the clamping assembly and then adjusting the assembly, making the operation more convenient.

[0017] In technical solution two, by fixing the position of the second clamp relative to the test container and having the screw specifically drive the movement of the first clamp, a clear and stable reference datum is established for the entire displacement measurement process. Under this structure, all displacements calculated by the angle encoder can be definitively attributed to the movement of the first clamp relative to this fixed datum, i.e., the actual change in the sample's length. This design eliminates systematic errors that may be introduced by the simultaneous movement of both clamps or an unclear reference datum, thereby further improving the accuracy of displacement measurement.

[0018] In technical solution three, a sliding rod slidably connected to the first clamp is added to the adjustment assembly, providing guidance and anti-rotation functions for the moving clamp. The screw transmits axial driving force, while the sliding rod ensures that the first clamp moves strictly along a preset straight path under force, suppressing any torsional motion that may occur under screw drive. The separation and coordination of the driving and guiding functions ensures that the deformation applied to the sample is purely axial tension, avoiding interference from non-axial motion or torsional components on the test results.

[0019] In technical solution four, by increasing the number of slide bars to two and arranging them on both sides of the first clamp, the guiding effect of the slide bars on the clamping assembly becomes more stable and reliable. Compared with the single slide bar structure, the double slide bar structure can prevent the first clamp from tilting or swaying due to uneven force, making the entire movement process of the first clamp more stable and smooth.

[0020] In technical solution five, a scale is added to the slide bar, which allows for intuitive observation of the dimensional changes of the polymer.

[0021] In technical solution six, the first fixture is formed by a slider and a first clamping head fixedly connected together. The slider and the screw are directly threaded together, forming a transmission pair that converts rotary motion into linear motion. Designing the slider responsible for transmission and the clamping head responsible for clamping the sample as two independent components that are fixedly connected to each other allows the transmission function and the clamping function to be structurally separated, making the overall structure more reliable and reducing manufacturing costs.

[0022] In technical solution seven, the fixing method of the second clamp and the sample clamping surfaces of the two clamps are further improved. The second clamp is stably set on the test container by the base, which can prevent the second clamp from shaking. The clamping surface is made of elastic rubber material with anti-slip texture, which can provide a sufficiently large clamping force by increasing the contact area and the coefficient of friction without damaging the fragile surface of the sample. This can effectively prevent the sample from slipping in the clamp due to excessive tension during the test, thereby avoiding measurement errors caused by such relative sliding.

[0023] In technical solution eight, by adding a support, together with the base, a stable mounting base is provided for both ends of the screw and the slide rod.

[0024] In technical solution nine, by setting a crank connected to the screw on the outside of the test container, the operator can manually control the tensile process of the sample in real time and continuously without opening the test container or disrupting the stable internal temperature environment.

[0025] In technical solution ten, by adding a temperature sensor and a temperature control unit to the test container, the temperature control method of the device is upgraded from simple open-loop heating to precise closed-loop automatic control. The temperature sensor monitors the actual temperature inside the test container in real time and transmits it as a feedback signal to the temperature control unit. The control unit then compares this feedback value with the preset target temperature and automatically adjusts the output power of the heating and cooling devices based on the deviation between the two using an internal algorithm. This closed-loop control system can accurately maintain the internal temperature at the set value and actively compensate for disturbances caused by changes in ambient temperature or heat loss from the equipment itself. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a side view of the structure of the thermotropic shape memory polymer performance testing device according to an embodiment of the present invention;

[0028] Figure 2 This is a top view of the structure of the thermotropic shape memory polymer performance testing device according to an embodiment of the present invention.

[0029] Explanation of key figure labels:

[0030] Test container 10;

[0031] Clamping assembly 20; First clamp 21; Second clamp 22; Slider 23; First clamping head 24; Base 25; Second clamping head 26;

[0032] Adjustment component 30; screw 31; slide bar 32; support 33; crank handle 34;

[0033] Ranging component 40; Angle encoder 41. Detailed Implementation

[0034] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are preferred embodiments of the present utility model and should not be considered as excluding other embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0035] Unless otherwise expressly defined, the use of terms such as "first," "second," or "third" in the claims, description, and drawings of this utility model is for distinguishing different objects and not for describing a specific order.

[0036] Unless otherwise expressly defined, in the claims, description, and accompanying drawings of this utility model, the use of directional terms such as "center," "lateral," "longitudinal," "horizontal," "vertical," "top," "bottom," "inner," "outer," "upper," "lower," "front," "rear," "left," "right," "clockwise," and "counterclockwise" to indicate orientation or positional relationships is based on the orientation and positional relationships shown in the accompanying drawings and is only for the convenience of describing this utility model and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the specific protection scope of this utility model.

[0037] Unless otherwise expressly defined, the terms "fixed connection" or "fixed connection" used in the claims, description and drawings of this utility model shall be interpreted broadly to refer to any connection in which there is no displacement or relative rotation relationship between the two parties, including non-removable fixed connection, detachable fixed connection, integral connection and fixed connection through other devices or components.

[0038] In the claims, description and accompanying drawings of this utility model, the terms "comprising", "having", and variations thereof are used to mean "including but not limited to".

[0039] Example

[0040] This invention relates to a device for testing the properties of thermotropic shape memory polymers, as described in the following embodiments. Figure 1 and Figure 2 The testing device includes a test container, a clamping assembly, an adjustment assembly, and a ranging assembly.

[0041] The test container is designed to control its internal temperature using a heating and cooling system. Specifically, the test container 10 is a box-like structure with walls made of a low thermal conductivity insulating material, such as polyurethane foam or aerogel board, to minimize heat exchange with the external environment and maintain a stable internal temperature. A transparent observation window is provided on the box or door of the test container 10. This window can be a double-layered, hollow tempered glass structure, ensuring that the operator can clearly observe the sample state without disturbing the internal temperature field, while also providing good insulation. The test container 10 is connected to an external heating and cooling system, which can be a Peltier effect-based thermoelectric cooler (TEC) system or an external constant-temperature liquid circulating bath. This system uses a circulating medium (such as air or heat transfer oil) to actively and rapidly heat or cool the interior of the test container 10.

[0042] Preferably, the test container is equipped with a temperature sensor and a temperature control unit. The temperature sensor is adapted to detect the internal temperature of the test container; the temperature control unit is adapted to control the temperature inside the test container through the heating and cooling device based on the signal transmitted by the temperature sensor. Specifically, the temperature sensor can be a high-precision platinum resistance thermometer (e.g., PT100 model) or a K-type thermocouple, with its measuring end positioned near the center of the polymer sample to accurately and sensitively reflect the real-time ambient temperature of the sample. The temperature control unit is an independent controller or a module integrated into the main control system, and its core can employ a PID (proportional-integral-derivative) control algorithm. This unit receives the real-time temperature signal from the temperature sensor and compares it with a user-preset target temperature value (e.g., the glass transition temperature Tg+20℃ of the polymer). Based on the deviation between the two, the PID algorithm accurately calculates the output power required by the heating and cooling device, thereby achieving precise control of the internal temperature and stabilizing it at the set value, with fluctuations controlled within ±0.5℃.

[0043] The clamping assembly, installed in the test container, includes a first clamp and a second clamp arranged opposite to each other along a first direction; the first clamp and the second clamp are used to clamp the thermotropic shape memory polymer. Specifically, the first clamp 21 and the second clamp 22 are structurally designed to firmly clamp the sample without damaging its surface. The clamping surfaces in direct contact with the sample are made of a material with a high coefficient of friction and appropriate elasticity, such as silicone rubber or polyurethane. The clamping surfaces are also machined with fine anti-slip textures, such as parallel grooves, intersecting mesh patterns, or a diamond-coated coating, such as a mesh pattern with a depth of 1.5 mm, to increase friction and effectively prevent the sample from slipping under tensile force. In addition, the clamps themselves can be designed as a quick-change structure, for example, connected to a slider or base by dovetail grooves, locating pins, or magnetic attraction, so as to easily change to different types of clamps according to the shape (such as film, fiber, dumbbell-shaped sample) and size of the sample to be tested.

[0044] In this clamping assembly, the second clamp is fixed relative to the test container; the screw is driven by the first clamp and is adapted to drive the first clamp to move in a first direction. In this embodiment, the second clamp includes a base and a second clamping head fixedly connected to each other; the base is fixed to the test container. Specifically, the second clamping head 26 is mounted on the base 25, which is securely mounted on the inner bottom plate or internal frame of the test container 10 using bolts or other fasteners. This rigid fixing method ensures that the position of the second clamp 22 remains absolutely unchanged throughout the entire test, thus providing a stable reference for displacement measurement. The base 25 itself is a solid metal block, which, in addition to fixing the second clamping head 26, also serves as a support fixing point for one end of the screw 31 and the slide bar 32.

[0045] An adjustment assembly, installed within the test container, includes a screw tractor tractor driveably connected to the clamping assembly. The screw tractor is adapted to rotate relative to the test container about a first axis in a first direction, thereby causing the first and second clamps to move closer or further apart along the first direction. Specifically, the screw tractor 31 is a precision transmission screw, which can be a trapezoidal screw or a ball screw, having a precise and known pitch, for example, with a pitch error controlled within ±0.05 mm. The screw tractor 31 is horizontally mounted along the first direction, and its rotational motion is precisely converted into linear displacement of the first clamp 21 through a threaded engagement with the slider 23 on the first clamp 21.

[0046] The adjustment assembly further includes a slide bar extending along a first direction and fixed relative to the test container; the first clamp is slidably connected to the slide bar along the first direction and is anti-rotationally engaged with the slide bar relative to the first axis. In this embodiment, there are two slide bars, arranged on both sides of the first clamp along a second direction perpendicular to the first direction. Specifically, to ensure that the first clamp 21 does not rotate with the screw 31 during movement, thereby ensuring that the force applied to the sample is purely axial tension, two parallel slide bars 32 are provided in the device. These two slide bars are steel cylindrical rods with precision-ground and hard chrome-plated surfaces, and their ends are fixed to the support 33 and the base 25, respectively. The slider 23 of the first clamp 21 has a precision through hole that mates with the slide bar 32, and a linear bearing can be installed in the hole. The slider 23 slides on the two slide bars 32. This structure restricts the rotational freedom of the slider, so that it can only move smoothly in a straight line along the axis of the slide bar (i.e., the first direction). To ensure smooth movement and accurate guidance, the surface roughness of the two slide rods 32 is no higher than Ra1.6μm, and the parallelism error after installation is controlled within ±0.2mm.

[0047] Preferably, the sliders are equipped with scales along the first direction. Specifically, millimeter-level length markings are created on the surface of one or two sliders 32 using laser etching or etching processes. Simultaneously, a pointer or vernier is installed at a corresponding position on the side of the slider 23, thus forming a direct-reading measurement system. This scale can be used for rapid reading and rough positioning of the initial sample length before testing, as well as for intuitive verification of electronic measurement results during the experiment.

[0048] In addition, the adjustment assembly includes a crank handle located outside the test container and coaxially connected to the screw, which drives the screw to rotate. Specifically, one end of the screw 31 protrudes from the wall of the test container 10 through a bearing with a sealing ring and is coaxially connected to the externally mounted crank handle 34. This design allows the operator to manually rotate the crank handle 34 to drive the screw 31 to rotate without opening the test container or disrupting the internal constant temperature environment, thereby enabling real-time and continuous control of the sample tensile process. The crank handle 34 can be a simple crank or a star wheel with multiple handles for fine adjustment. Alternatively, a torque adjustment device, such as an adjustable friction clutch, can be integrated into the crank handle 34, allowing the operator to set an approximate tensile force and improve operational consistency.

[0049] The first clamp includes a slider and a first clamping head fixedly connected to each other; the slider and the screw are threadedly connected in a first direction; the first clamping head is used to clamp the thermotropic shape memory polymer. Specifically, the first clamp 21 adopts a modular design, consisting of two independent components: a slider 23 and a first clamping head 24. The slider 23 is the core component for realizing motion transmission and guidance. Its main body is a metal block with a threaded hole inside that meshes with the screw 31, and two smooth through holes (or fitted with linear bearings) that slide with the two sliders 32. The first clamping head 24 is the part that directly clamps the sample, and it is detachably fixed to the end face of the slider 23 by screws or other means. This separate design simplifies manufacturing and maintenance; when different types of clamping heads need to be replaced, it is not necessary to disassemble the entire transmission and guidance system.

[0050] In this embodiment, the clamping surfaces of the first and second clamping heads used to clamp the thermotropic shape memory polymer are made of rubber and have anti-slip textures. Specifically, the clamping surfaces of both clamping heads are covered with pads made of silicone rubber. Silicone rubber is chosen because it provides a high coefficient of friction to prevent sample slippage while also being flexible enough not to damage or cut the polymer sample under clamping force. The pad surface is molded with specific anti-slip textures, such as diamond or stripe grooves with a depth of 1.5 mm. This texture can embed into the sample surface, further enhancing the reliability of clamping and ensuring that the measured displacement is entirely due to the deformation of the sample itself, rather than the relative sliding between the sample and the clamp.

[0051] The ranging assembly includes an angle encoder coaxially connected to the screw, which measures the rotation angle of the screw to calculate the relative displacement of the first and second clamps in the clamping assembly based on the rotation angle and the screw pitch. Specifically, a high-resolution rotary angle encoder 41 has its shaft directly and rigidly coaxially connected to the end of the screw 31. This encoder can be incremental or absolute, with an accuracy, for example, better than 0.1 degrees. When the crank 34 drives the screw 31 to rotate, the angle encoder 41 rotates synchronously and outputs an electrical signal proportional to the rotation angle (e.g., an orthogonal pulse signal output by an incremental encoder). This signal is sent to a data processing unit (e.g., a microcontroller or a data acquisition card connected to a computer). The data processing unit calculates the linear displacement ΔL of the first clamp 21 by counting pulses or directly reading the absolute angle value, according to the following formula: ΔL = (θ / 360) × P. Where θ is the measured rotation angle (unit: degrees), and P is the precise screw pitch of the screw 31 (unit: millimeters / revolution). The calculated displacement can be displayed on the screen in real time or recorded for subsequent performance analysis calculations.

[0052] The assembly process of the thermotropic shape memory polymer performance testing device involved in this embodiment is as follows:

[0053] First, install the core components. Securely fix the support 33 and base 25 to the designated positions inside the test container 10 using bolts or other fasteners, ensuring that they are installed firmly and aligned. Then, install the two slide rods 32 parallel between the support 33 and base 25, and use a calibration tool to ensure that the parallelism error of the two slide rods 32 is within the specified range (e.g., ±0.2 mm).

[0054] Next, the transmission and guiding system is assembled. The slider 23 is fitted onto the two sliders 32, with its internal threaded holes engaging with the threads of the screw 31. The two ends of the screw 31 are respectively mounted on the bearing seats of the support 33 and the base 25. The rotating shaft of the angle encoder 41 is coaxially connected to and fixed to one end of the screw 31, and the crank handle 34 is mounted on the other end of the screw 31 that extends out of the test container 10.

[0055] Next, install the clamping components. Select the appropriate clamping head according to the type of sample to be tested, install the first clamping head 24 on the slider 23 to form the first clamp 21; install the second clamping head 26 on the base 25 to form the second clamp 22.

[0056] Finally, perform system connection and debugging. Connect the temperature control unit, temperature sensor, and heating / cooling device; set the target temperature; and check whether the temperature control system can work normally and stabilize the temperature at the set value. Connect the angle encoder 41 to the data processing unit; turn the crank handle 34; and check whether the displacement measurement system can accurately calculate and display the displacement.

[0057] The testing process of the thermotropic shape memory polymer performance testing device involved in this embodiment is as follows:

[0058] Step 1: Sample Preparation and Installation. Based on the shape (e.g., film or fiber) and size of the polymer sample to be tested, select and install the matching first clamping head 24 and second clamping head 26. Turn the crank handle 34 to adjust the position of the first clamp 21 so that the distance between the two clamps is suitable for sample installation. Fix one end of the sample to be tested onto the second clamp 22 and the other end onto the first clamp 21, ensuring the sample is firmly clamped and in a naturally straight state. Record the initial distance between the two clamps at this point using the scale on the distance measuring component 40 or the slide bar 32, denoted as L0.

[0059] The second step is shape programming. The door of the test container 10 is closed, and the temperature control system is set and activated to raise the temperature inside the test container 10 to the material's programmed temperature (e.g., 10°C to 30°C above its glass transition temperature Tg), and this temperature is maintained for a period to ensure uniform sample temperature. Then, the operator rotates the crank handle 34 at a constant speed, driving the first clamp 21 to move away from the second clamp 22, stretching the sample. During the stretching process, the data processing unit calculates and displays the stretched length of the sample in real time based on the signal from the angle encoder 41. When the preset programmed length L is reached... load When the rotation stops, the rotation ceases.

[0060] The third step is shape fixation and fixation rate calculation. Maintain sample length L. load With the temperature remaining constant, initiate cooling to rapidly lower the temperature inside the test container 10 to a fixed temperature well below its glass transition temperature. Once the sample has completely cooled, release the clamps and remove the load. Measure the length of the sample at this point and record it as the shape-fixed length L. f According to formula R f =(L load -L0) / (L f -L0) is used to calculate the shape fixation rate of the sample.

[0061] Step 4: Shape Recovery and Recovery Rate Calculation. Place the shaped sample back between the clamps (without applying preload) and close the chamber door. Reactivate the temperature control system to raise the temperature inside the test container 10 to the material's recovery temperature (e.g., 5°C to 20°C above its glass transition temperature Tg) and maintain this temperature. Under thermal action, the sample will spontaneously recover its original shape. Once the sample length no longer changes, indicating shape recovery is complete, measure its final length and record it as the shape recovery length L. r According to formula R r =(L f -L r ) / (L f -L0) is used to calculate the shape recovery rate of the sample.

[0062] By following the steps above, accurate and reliable quantitative testing of the shape fixation and recovery properties of thermotropic shape memory polymers can be completed.

[0063] This embodiment relates to a performance testing device for thermotropic shape memory polymers, comprising a test container, a clamping assembly, an adjustment assembly, and a ranging assembly. Through the cooperation of these components, high-precision and high-reliability testing of the performance of thermotropic shape memory polymers is achieved. The test container, through a heating and cooling device, can precisely control the internal temperature, providing a stable and adaptable environment for polymer performance testing. Furthermore, the clamping assembly and adjustment assembly are both housed within the test container. This integrated design allows the entire process of tensile deformation and shape recovery of the sample to be completed within a stable and precise temperature field, avoiding temperature fluctuations and operational errors introduced by the need to transfer the sample between heating and measuring equipment in existing technologies. The clamping assembly conveniently clamps and fixes the polymer. Simultaneously, the clamping assembly and the adjustment assembly are connected by a screw drive, which converts rotational operations into displacement of the clamping assembly. With the addition of an angle encoder, the real-time displacement of the clamp can be accurately calculated by acquiring the electrical signal from the angle encoder and combining it with the screw pitch, improving the problem of poor accuracy control of displacement during manual operation in existing technologies. Furthermore, when conducting performance tests, the polymer can be easily obtained by simply clamping it onto the clamping assembly and then adjusting the assembly, making the operation more convenient.

[0064] The foregoing description of the specifications and embodiments is intended to explain the scope of protection of this utility model, but does not constitute a limitation on the scope of protection of this utility model. Modifications, equivalent substitutions, or other improvements to the embodiments of this utility model or a portion thereof that can be obtained by those skilled in the art through logical analysis, reasoning, or limited experimentation, based on the teachings of this utility model or the foregoing embodiments, should all be included within the scope of protection of this utility model.

Claims

1. A device for testing the properties of thermotropic shape memory polymers, characterized in that, include: Test container (10), which is adapted to control the internal temperature by means of a heating and cooling device; The clamping assembly (20) is installed in the test container (10) and includes a first clamp (21) and a second clamp (22) arranged opposite to each other along a first direction; the first clamp (21) and the second clamp (22) are used to clamp the thermotropic shape memory polymer; An adjustment assembly (30), installed in the test container (10), includes a screw (31) tractively connected to the clamping assembly (20); the screw (31) is adapted to rotate relative to the test container (10) about a first axis in a first direction, so as to drive the first clamp (21) and the second clamp (22) to move closer to or further away from each other along the first direction; and The ranging assembly (40) includes an angle encoder (41) coaxially connected to the screw (31), the angle encoder (41) being used to measure the rotation angle of the screw (31) to calculate the relative displacement of the first clamp (21) and the second clamp (22) in the clamping assembly (20) based on the rotation angle and the pitch of the screw (31).

2. The thermotropic shape memory polymer performance testing device as described in claim 1, characterized in that, In the clamping assembly (20), the second clamp (22) is fixed relative to the test container (10); the screw (31) is connected to the first clamp (21) and is adapted to drive the first clamp (21) to move in a first direction.

3. The thermotropic shape memory polymer performance testing device as described in claim 2, characterized in that, The adjustment assembly (30) further includes a slide bar (32) extending along a first direction and fixed relative to the test container (10); the first clamp (21) is slidably connected to the slide bar (32) along the first direction and engages with the slide bar (32) to prevent rotation relative to the first axis.

4. The thermotropic shape memory polymer performance testing device as described in claim 3, characterized in that, There are two slide bars (32), which are arranged on both sides of the first clamp (21) along a second direction perpendicular to the first direction.

5. A thermotropic shape memory polymer performance testing device as described in claim 3 or 4, characterized in that, The slide bar (32) is provided with a scale along the first direction.

6. The thermotropic shape memory polymer performance testing device as described in claim 4, characterized in that, The first clamp (21) includes a slider (23) and a first clamping head (24) fixedly connected to each other; the slider (23) is threadedly connected to the screw (31) in a first direction; the first clamping head (24) is used to clamp the thermotropic shape memory polymer.

7. The thermotropic shape memory polymer performance testing device as described in claim 6, characterized in that, The second clamp (22) includes a base (25) and a second clamping head (26) fixedly connected to each other; the base (25) is fixed to the test container (10); the clamping surfaces of the first clamping head (24) and the second clamping head (26) used to clamp the thermotropic shape memory polymer are made of rubber and have anti-slip texture.

8. The thermotropic shape memory polymer performance testing device as described in claim 7, characterized in that, The adjustment assembly (30) further includes a support (33); the support (33) is fixed to the test container (10) and located at the other end relative to the base (25) in a first direction; the two ends of the screw (31) are rotatably mounted on the support (33) and the base (25); the two ends of the slide rod (32) are mounted on the support (33) and the base (25); the angle encoder (41) is mounted on the support (33) or the base (25).

9. The thermotropic shape memory polymer performance testing device as described in claim 1, characterized in that, The adjustment assembly (30) also includes a crank (34) located outside the test container (10) and coaxially connected to the screw (31), the crank (34) being used to drive the screw (31) to rotate.

10. The thermotropic shape memory polymer performance testing device as described in claim 1, characterized in that, The test container (10) is equipped with a temperature sensor and a temperature control unit; the temperature sensor is adapted to detect the internal temperature of the test container (10); the temperature control unit is adapted to control the temperature inside the test container (10) through the heating and cooling device according to the signal transmitted by the temperature sensor.

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