A driving device and test method for cyclic stretching and bending of polymer materials

Abstract

The present invention relates to the technical field of flexible electroactive polymer material performance testing technology, and specifically to a drive device and test method for cyclic stretching and bending of polymer materials, which can perform cyclic stretching / bending tests on flexible polymer materials. The structure of the fixed module in the drive device can be adjusted in two levels to meet the test requirements of samples of different lengths. The stroke of the moving slider is adjusted by the eccentricity of the eccentric wheel to achieve precise control of the stretching / bending deformation of the sample, with an accuracy of up to 0.1mm. The motor drives the eccentric wheel to drive the moving slider to move back and forth, and the sample can be stretched / bent within a range of 0 to 5Hz. The present invention is easy to operate, produces accurate test results, is applicable to polymer materials of different sizes and moduli, and has the characteristics of adjustable drive distance, high accuracy, and a wide frequency range.

Description

Technical Field

[0001] The present invention relates to the technical field of flexible electroactive polymer material performance testing, and in particular to a driving device and a testing method for cyclic stretching and bending of polymer materials. Background Art

[0002] Electroactive polymers, represented by piezoelectric polymers, ion gels, and dielectric elastomers, and their composite materials can generate continuous electrical signals under the periodic action of external forces such as stretching and bending, and have great application prospects in the fields of energy harvesting, intelligent sensing, and flexible driving. Therefore, a driving device that can be used for cyclic stretching and compression bending experiments of polymers and their composite materials is of great significance for the performance research and device application of flexible electroactive materials. In view of the characteristics of electroactive polymer materials such as large deformation, easy cutting and adjustable size, and wide application scenarios, the driving device used for cyclic stretching and compression bending experiments of electroactive polymer materials needs to have three key functions: (1) the position of the clamps fixing the two ends of the sample can be adjusted to meet the test requirements of polymer materials and devices of different sizes; (2) the driving unit that drives the sample to stretch / bend has an adjustable stroke and high displacement accuracy to widely match the deformation characteristics of different materials; (3) the movement frequency of the driving unit is adjustable to meet the test requirements of samples with different moduli and different application scenarios. At present, the driving devices of existing mechanical testing machines on the market are mainly based on servo motors, which are prone to wear when running at high speeds and are difficult to meet the test requirements of flexible materials under conditions such as small deformation or high-frequency driving. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a driving device and a testing method for cyclic stretching and bending of polymer materials, which are easy to operate and have accurate test results. They can be applied to polymer materials of different sizes and moduli, and have the characteristics of adjustable driving distance, high precision and wide frequency range.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] 1. A driving device for cyclic stretching and bending of polymer materials

[0006] The present invention provides a driving device for cyclic stretching and bending of polymer materials, which is used for a polymer material with a modulus range of 10 2 ~10 9 Pa electroactive polymer and its composite material periodic tensile and bending test, mainly includes a base 1, a guide rail 2, a sample fixing module, a sample driving module, and an electric-force conversion module, wherein the guide rail 2 is provided on the upper end surface of the base 1;

[0007] The sample fixing module includes a first slider 3 fixedly mounted on the guide rail 2, a second slider 4 fixedly mounted above the first slider 3, and the mounting position of the first slider 3 on the guide rail 2 and the mounting position of the second slider 4 on the first slider 3 are both adjustable, a fixing device 5 is fixedly connected to the top of the second slider 4, and a sample fixing end clamping portion is provided at the end of the fixing device 5;

[0008] The sample driving module includes a moving slider 11 slidably mounted on the guide rail 2. A sample driving end clamping portion is provided on the top of the moving slider 11, and the initial spacing between the sample driving end clamping portion and the sample fixing end clamping portion is adapted to the original length of the test sample.

[0009] The electric-to-power conversion module includes a ball-end connecting rod 14 for driving the moving slider 11 to slide along the guide rail 2. The ball-end connecting rod 14 is installed on the eccentric wheel 15. The eccentric wheel 15 is connected to the driving end of the motor 16. The motor 16 is fixedly mounted on the base 1 through the motor clamp 19.

[0010] Furthermore, the sample fixed end clamping portion includes a clamp base 7 fixedly connected to the end of the fixing device 5, and a clamp clamp plate 8 is provided above the clamp base 7. The clamp base 7 and the clamp clamp plate 8 are connected by a clamping nut 9 to clamp the fixed end of the test sample.

[0011] Furthermore, the sample driving end clamping portion includes a second clamping plate 12, and the second clamping plate 12 is connected to the top of the moving slider 11 through a second clamping nut 13 to clamp the driving end of the test sample.

[0012] Furthermore, a groove 21 is provided on the guide rail 2, and a plurality of screw holes 22 are evenly provided in the groove 21. The first slider 3 is fixed to different screw holes 22 by screws to adjust the installation position of the first slider 3 on the guide rail 2, thereby completing the first-level adjustment of the distance between the clamping part of the sample driving end and the clamping part of the sample fixing end.

[0013] Furthermore, a slide groove is provided on the top of the first slider 3, and the bottom of the second slider 4 is slidably engaged in the slide groove and fixed by a pin to adjust the installation position of the second slider 4 on the first slider 3, thereby completing the secondary adjustment of the distance between the clamping part of the sample driving end and the clamping part of the sample fixing end.

[0014] Furthermore, a stress sensor 6 is installed on the fixture base 7 , and the stress sensor 6 is electrically connected to a stress display panel 10 installed on the side of the base 1 to monitor the stress changes of the test sample during the test.

[0015] Furthermore, a fixing device 20 is provided on the side of the motor 16, and an infrared tachometer 17 is installed on the fixing device 20. The infrared tachometer 17 is electrically connected to a speed display panel 18 installed on the side of the base 1 to monitor the speed changes of the motor drive end during the test.

[0016] Furthermore, the eccentricity of the eccentric wheel 15 is adjusted to control the movement distance of the moving slider 11 on the guide rail 2, thereby regulating the stretching and bending degrees of the test sample. The control accuracy of the movement distance of the moving slider 11 on the guide rail 2 is 0.1 mm.

[0017] Furthermore, the rotation speed of the driving end of the motor 16 is adjusted to control the stretching and bending cycle frequency of the test sample, and the control range of the cycle frequency is 0~5 Hz.

[0018] 2. A test method for cyclic stretching and bending of polymer materials

[0019] Based on the same inventive concept, the present invention also provides a test method for cyclic stretching and bending of polymer materials, based on the above-mentioned driving device, specifically comprising the following steps:

[0020] S1, determining the stroke of the moving slider according to the test deformation of the test sample, and setting the eccentricity of the eccentric wheel and the initial position of the moving slider on the guide rail according to the stroke;

[0021] S2, determining the distance between the fixed end and the driving end of the sample according to the original length of the test sample, and adjusting the relative position of the first slider on the guide rail and the relative position of the second slider on the first slider in accordance with the distance;

[0022] S3, fixing the two ends of the test sample to the sample fixing end clamping part and the sample driving end clamping part respectively;

[0023] S4, set the motor speed according to the test frequency of the test sample. The motor drive end drives the eccentric wheel to rotate and drives the moving slider to move along the guide rail through the ball head connecting rod, so that the test sample undergoes periodic tensile / bending tests according to the set test deformation and test frequency.

[0024] Compared with the prior art, the present invention has the following main advantages:

[0025] 1. The present invention provides a drive device for cyclic stretching and bending of polymer materials, which can perform periodic stretching / bending tests on flexible polymer materials. The structure of the fixed module in the drive device can be adjusted in two levels to meet the testing requirements of samples of different lengths. By adjusting the stroke of the moving slider by the eccentricity of the eccentric wheel, the stretching / bending deformation of the sample can be precisely controlled with an accuracy of up to 0.1 mm. By adjusting the motor speed, the frequency of the sample stretching / bending test can be efficiently controlled, so that the test frequency can be arbitrarily adjusted within the range of 0 to 5 Hz.

[0026] 2. The present invention also provides a test method for cyclic stretching and bending of polymer materials. Based on the driving device for cyclic stretching and bending of polymer materials, the overall operation is quick and convenient, and the test results are accurate. It can be applied to cyclic stretching / bending tests of polymer materials of different sizes and different moduli, and has the characteristics of adjustable driving distance, high precision and wide frequency range. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the overall structure of a driving device for cyclic stretching and bending of polymer materials according to an embodiment of the present invention;

[0028] Figure 2 Schematic diagram of the structure of the guide rail in an embodiment of the present invention;

[0029] Figure 3 Flowchart of the test method in the embodiment of the present invention;

[0030] Figure 4 This is a diagram of the electrical signal generated by a bending test of a PVDF sample driven by the device in an embodiment of the present invention;

[0031] Figure 5 This is a diagram of the electrical signal generated by the tensile test of the ion gel sample in an embodiment of the present invention when driven by the device.

[0032] In the figure: 1-base; 2-guide rail; 3-first slider; 4-second slider; 5-fixing device; 6-stress sensor; 7-clamp base; 8-clamp plate 1; 9-clamping nut 1; 10-stress display panel; 11-moving slider; 12-clamp plate 2; 13-clamping nut 2; 14-ball head connecting rod; 15-eccentric wheel; 16-motor; 17-infrared tachometer; 18-speed display panel; 19-motor clamp; 20-fixing device; 21-groove; 22-screw hole. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0034] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0035] Example 1: This embodiment provides a driving device for cyclic stretching and bending of polymer materials, which is used for 2 ~10 9 Cyclic tensile / bending test of Pa polymers and their composites (electroactive flexible polymer materials such as piezoelectric polymers, ion gels, and dielectric elastomers). In this embodiment, the polymer can specifically be polyvinylidene fluoride (PVDF) or polydimethylsiloxane (PDMS), and the composite material can specifically be polydimethylsiloxane / barium titanate (PDMS / BTO), where the mass fraction of barium titanate (BTO) can be arbitrarily selected from 0 to 50%.

[0036] like Figures 1 and 2 As shown, the driving device mainly includes: a base 1, a guide rail 2, a sample fixing module, a sample driving module, and an electric-to-power conversion module; wherein the guide rail 2 is arranged on the upper end surface of the base 1.

[0037] The sample fixing module includes a first slider 3 fixedly mounted on the guide rail 2, a second slider 4 fixedly mounted above the first slider 3, and the mounting position of the first slider 3 on the guide rail 2 and the mounting position of the second slider 4 on the first slider 3 are both adjustable, a fixing device 5 is fixedly connected to the top of the second slider 4, and a sample fixing end clamping portion is provided at the end of the fixing device 5;

[0038] The sample driving module includes a moving slider 11 slidably mounted on the guide rail 2. A sample driving end clamping portion is provided on the top of the moving slider 11, and the initial spacing between the sample driving end clamping portion and the sample fixing end clamping portion is adapted to the original length of the test sample.

[0039] The electric-to-power conversion module includes a ball-end connecting rod 14 for driving the moving slider 11 to slide along the guide rail 2. The ball-end connecting rod 14 is installed on the eccentric wheel 15. The eccentric wheel 15 is connected to the driving end of the motor 16. The motor 16 is fixedly mounted on the base 1 through the motor clamp 19.

[0040] Furthermore, the sample fixed end clamping portion includes a clamp base 7 fixedly connected to the end of the fixing device 5, and a clamp clamp plate 8 is provided above the clamp base 7. The clamp base 7 and the clamp clamp plate 8 are connected by a clamping nut 9 to clamp the fixed end of the test sample.

[0041] Furthermore, the sample driving end clamping portion includes a second clamping plate 12, and the second clamping plate 12 is connected to the top of the moving slider 11 through a second clamping nut 13 to clamp the driving end of the test sample.

[0042] Furthermore, a groove 21 is provided on the guide rail 2, and a plurality of screw holes 22 are evenly provided in the groove 21. The first slider 3 is fixed to different screw holes 22 by screws to adjust the installation position of the first slider 3 on the guide rail 2, thereby completing the first-level adjustment of the distance between the clamping part of the sample driving end and the clamping part of the sample fixing end.

[0043] Furthermore, a slide groove is provided on the top of the first slider 3, and the bottom of the second slider 4 is slidably engaged in the slide groove and fixed by a pin to adjust the installation position of the second slider 4 on the first slider 3, thereby completing the secondary adjustment of the distance between the clamping part of the sample driving end and the clamping part of the sample fixing end.

[0044] Furthermore, a stress sensor 6 is installed on the fixture base 7 , and the stress sensor 6 is electrically connected to a stress display panel 10 installed on the side of the base 1 to monitor the stress changes of the test sample during the test.

[0045] Furthermore, a fixing device 20 is provided on the side of the motor 16, and an infrared tachometer 17 is installed on the fixing device 20. The infrared tachometer 17 is electrically connected to a speed display panel 18 installed on the side of the base 1 to monitor the speed changes of the motor drive end during the test.

[0046] Furthermore, the eccentricity of the eccentric wheel 15 is adjusted to control the movement distance of the moving slider 11 on the guide rail 2, thereby regulating the stretching and bending degrees of the test sample. The control accuracy of the movement distance of the moving slider 11 on the guide rail 2 is 0.1 mm.

[0047] Furthermore, the rotation speed of the driving end of the motor 16 is adjusted to control the stretching and bending cycle frequency of the test sample, and the control range of the cycle frequency is 0~5 Hz.

[0048] Example 2. This example provides a driving device for cyclic stretching and bending of polymer materials. One end of the sample is fixed, and the other end of the sample moves linearly with the slider, so that the sample is stretched or bent under the drive of the moving slider. To achieve the above goal, the motor drives the eccentric wheel to move, and the eccentric wheel drives the slider to move through the ball head connecting rod, converting the rotation into linear motion. The slider movement frequency can be controlled by adjusting the motor speed, and the slider movement stroke can be controlled by adjusting the eccentricity of the eccentric wheel, thereby controlling the frequency and deformation of the sample periodic stretching / bending.

[0049] The sample fixing module includes a first slider 3, a second slider 4, a fixing device 5, a stress sensor 6, a clamp base 7, a clamp plate 8, a clamping nut 9, and a stress display panel 10; the first slider 3 is fixed on the guide rail 2; the second slider 4 is fixed on the first slider 3; the clamp base 7 and the fixing device 5 are fixed on the second slider 4, and the stress sensor 6 is fixed between the clamp base 7 and the fixing device 5; the clamp plate 8 clamps the polymer and its composite material between the clamp base 7 and the clamp plate 8, and is fixed by a clamping nut 9; the stress display panel 10 is fixed on the base 1.

[0050] The sample driving module includes a moving slider 11, a clamping plate 2 12, and a clamping nut 2 13; the moving slider 11 is located on the guide rail 2 and can move back and forth on the slide rail; the clamping plate 2 12 clamps the polymer and its composite material between the moving slider 11 and the clamping plate 2 12, and is fixed by the clamping nut 2 13. The clamping plate and the nut 2 together constitute the sample driving end clamp.

[0051] The electric-to-power conversion module includes a ball-end connecting rod 14, an eccentric wheel 15, a motor 16, an infrared tachometer 17, a speed display panel 18, a motor fixture 19, and a fixing device 20; the motor 16 is fixed to the base 1 via the motor fixture 19; the motor 16 drives the eccentric wheel 15 to rotate and drives the moving slider 11 via the ball-end connecting rod 14; the infrared tachometer 17 is fixed to the base 1 via the fixing device 20 for detecting the speed of the motor 16; the speed display panel 18 is fixed to the base 1 for displaying the speed of the motor 16;

[0052] Furthermore, the guide rail 2 is fixed on the base 1. A groove is provided on the left half of the guide rail, and four screw holes are provided in the groove, which are used to define the position of the first slider 3.

[0053] Furthermore, the first slider 3 is fixed to the guide rail 2 by a nut. By fixing it to different screw holes, the relative position of the first slider 3 on the guide rail 2 can be adjusted, thereby adjusting the distance between the sample fixing module and the sample driving module according to the original length of the sample.

[0054] Furthermore, the second slider 4 can drive the sample fixing end clamp base 7, clamp splint 1 8, and clamping nut 1 9 to move on the first slider 3, so as to finely adjust the distance between the sample fixing end clamp base 7, clamp splint 1 8, clamping nut 1 9 and the sample driving end moving slider 11, clamp splint 2 12, and clamping nut 2 13.

[0055] Furthermore, a stress sensor 6 is connected to the end of the fixture base 7, and together with the stress display panel 10, the dynamic changes in the stress on the sample during the stretching / bending process can be monitored.

[0056] Furthermore, by adjusting the eccentricity of the eccentric wheel 15, the movement distance of the moving slider 11 is controlled, thereby regulating the stretching / bending degree of the sample. The displacement accuracy of the sample as the moving slider 11 moves can reach 0.1 mm.

[0057] Furthermore, the motor speed is adjusted to control the frequency of the sample tensile / bending test, and the applied frequency can be adjusted in the range of 0~5 Hz.

[0058] Example 3, based on the same inventive concept, this embodiment also provides a test method for cyclic stretching and bending of polymer materials, based on the driving device as described above, such as Figure 3 As shown, the specific steps include:

[0059] Step 1: Determine the travel of the moving slider based on the tensile / bending deformation of the test sample and set the eccentricity of the eccentric wheel with an accuracy of up to 0.1 mm. Based on the tensile / bending test requirements, rotate the eccentric wheel to adjust the moving slider to the extreme left / right end of the travel to determine the initial position of the moving slider on the guide rail.

[0060] Step 2: Determine the distance between the sample's fixed end and the driving end based on the original length of the test sample. The sample's driving end is fixed by the initial position of the moving slider. Adjust the relative position of the second slider on the first slider and the relative position of the first slider on the guide rail to determine the position of the fixture base and the fixture clamp in the fixing module, and then determine the position of the sample's fixed end.

[0061] Step 3: Fix the two ends of the test sample in the fixing fixture of the sample fixing module and the driving fixture of the sample driving module respectively;

[0062] Step 4: Set the motor speed according to the frequency of the sample's periodic stretching / bending test. The frequency can be adjusted within the range of 0 to 5 Hz. The motor rotation drives the eccentric wheel to rotate and drives the moving slider through the ball joint, so that the test sample is periodically stretched / bent according to the set deformation amount and frequency.

[0063] Example 4: In this example, the driving device is used to perform a bending test on a 30 cm long polyvinylidene fluoride (PVDF) film with an original length of 25 cm, a deformation of 20%, and a motion frequency of 1 Hz. The method is as follows:

[0064] Step 1: According to the test requirements, the bending deformation of the PVDF sample in the test is 5 cm. Adjust the eccentricity of the eccentric wheel to 5 cm. Manually rotate the eccentric wheel to move the moving slider to the far right (away from the end of the second slider);

[0065] Step 2: Based on the relative position of the moving slider on the guide rail, adjust the first slider and the second slider until the distance between the fixture base and the moving slider is 25 cm, thereby determining the position of the sample fixed end;

[0066] Step 3: Fix the two ends of the PVDF sample to the moving slider and the second slider respectively through the clamp plates and nuts, making sure that the PVDF sample is fully stretched without bending.

[0067] Step 4: According to the test requirements, the driving frequency of the sample is 1 Hz. Turn on the drive device switch and adjust the motor speed to 60 rpm / min. Then the PVDF sample begins to perform a periodic bending motion with a deformation of 20% and a frequency of 1 Hz. The electrical signal generated by the PVDF sample under this condition is as follows: Figure 4 shown.

[0068] Example 5: In this example, the above-mentioned driving device is used to perform a tensile test on an ion gel of 4 cm in length with an original length of 2 cm, a deformation of 100%, and a motion frequency of 0.5 Hz. The method is as follows:

[0069] Step 1: According to the test requirements, the tensile deformation of the ion gel sample in the test is 2 cm. Adjust the eccentricity of the eccentric wheel to 2 cm. Manually rotate the eccentric wheel to move the moving slider to the far left (near the end of the second slider).

[0070] Step 2: Based on the relative position of the moving slider on the guide rail, adjust the first slider and the second slider until the distance between the fixture base and the moving slider is 2 cm, thereby determining the position of the sample fixed end;

[0071] Step 3: Fix the two ends of the ion gel sample to the moving slider and the second slider respectively using the clamp plates and nuts, making sure that the ion gel sample is fully stretched without bending.

[0072] Step 4: According to the test requirements, the sample's driving frequency is 0.5 Hz. Turn on the drive device switch and adjust the motor speed to 30 rpm / min. The ion gel sample will then begin a periodic stretching motion with a deformation of 100% and a frequency of 0.5 Hz. The resistance change rate curve of the ion gel sample driven under this condition is shown in the figure below. Figure 5 shown.

[0073] Furthermore, all parts of this application that are not described in detail are the same as the existing technology or are implemented using the existing technology.

[0074] In summary:

[0075] 1. The present invention provides a drive device for cyclic stretching and bending of polymer materials, which can perform periodic stretching / bending tests on flexible polymer materials. The structure of the fixed module in the drive device can be adjusted in two levels to meet the testing requirements of samples of different lengths. By adjusting the stroke of the moving slider by the eccentricity of the eccentric wheel, the stretching / bending deformation of the sample can be precisely controlled with an accuracy of up to 0.1 mm. By adjusting the motor speed, the frequency of the sample stretching / bending test can be efficiently controlled, so that the test frequency can be arbitrarily adjusted within the range of 0 to 5 Hz.

[0076] 2. The present invention also provides a test method for cyclic stretching and bending of polymer materials. Based on the driving device for cyclic stretching and bending of polymer materials, the overall operation is quick and convenient, and the test results are accurate. It can be applied to cyclic stretching / bending tests of polymer materials of different sizes and different moduli, and has the characteristics of adjustable driving distance, high precision and wide frequency range.

[0077] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A driving device for cyclic stretching and bending of polymer materials, used for modulus range 10 2 ~10 9 Pa polymer and its composite material cyclic tensile and bending test, characterized in that, It comprises a base (1), a guide rail (2), a sample fixing module, a sample driving module, and an electric-to-power conversion module, wherein the guide rail (2) is arranged on the upper end surface of the base (1); The sample fixing module comprises a first slider (3) fixedly mounted on a guide rail (2), a second slider (4) fixedly mounted above the first slider (3), and the mounting position of the first slider (3) on the guide rail (2) and the mounting position of the second slider (4) on the first slider (3) are both adjustable, a first fixing device (5) is fixedly connected to the top of the second slider (4), and a sample fixing end clamping portion is provided at the end of the first fixing device (5); The sample driving module comprises a moving slider (11) slidably mounted on a guide rail (2), a sample driving end clamping portion is provided on the top of the moving slider (11), and an initial spacing between the sample driving end clamping portion and the sample fixing end clamping portion is adapted to the original length of the test sample; The electric-to-power conversion module includes a ball-end connecting rod (14) for driving a moving slider (11) to slide along a guide rail (2), wherein the ball-end connecting rod (14) is mounted on an eccentric wheel (15), and the eccentric wheel (15) is connected to a driving end of a motor (16), and the motor (16) is fixedly mounted on the base (1) via a motor clamp (19).

2. A driving device for cyclic stretching and bending of polymer materials according to claim 1, characterized in that: The sample fixed end clamping portion comprises a clamp base (7) fixedly connected to the end of the first fixing device (5), a clamp clamp plate 1 (8) is provided above the clamp base (7), and the clamp base (7) and the clamp clamp plate 1 (8) are connected via a clamping nut 1 (9) to clamp the fixed end of the test sample.

3. A driving device for cyclic stretching and bending of polymer materials according to claim 1, characterized in that: The sample driving end clamping portion includes a second clamping plate (12), and the second clamping plate (12) is connected to the top of the moving slider (11) through a second clamping nut (13) to clamp the driving end of the test sample.

4. A driving device for cyclic stretching and bending of polymer materials according to claim 1, characterized in that: The guide rail (2) is provided with a groove (21), and a plurality of screw holes (22) are evenly provided in the groove (21). The first slider (3) is fixed to different screw holes (22) by screws to adjust the installation position of the first slider (3) on the guide rail (2), thereby completing the first-level adjustment of the distance between the sample driving end clamping portion and the sample fixing end clamping portion.

5. A driving device for cyclic stretching and bending of polymer materials according to claim 4, characterized in that: A sliding groove is provided on the top of the first slider (3), and the bottom of the second slider (4) is slidably engaged in the sliding groove and fixed by a pin to adjust the installation position of the second slider (4) on the first slider (3), thereby completing the secondary adjustment of the distance between the sample driving end clamping part and the sample fixing end clamping part.

6. A driving device for cyclic stretching and bending of polymer materials according to claim 2, characterized in that: A stress sensor (6) is mounted on the fixture base (7), and the stress sensor (6) is electrically connected to a stress display panel (10) mounted on the side of the base (1) to monitor changes in the stress of the test sample during the test.

7. The driving device for cyclic stretching and bending of polymer materials according to claim 1, characterized in that: A second fixing device (20) is provided on the side of the motor (16), and an infrared tachometer (17) is installed on the second fixing device (20). The infrared tachometer (17) is electrically connected to a speed display panel (18) installed on the side of the base (1) to monitor the speed change of the motor drive end during the test.

8. The driving device for cyclic stretching and bending of polymer materials according to claim 1, characterized in that: The eccentricity of the eccentric wheel (15) is adjusted to control the movement distance of the moving slider (11) on the guide rail (2), thereby regulating the stretching and bending degrees of the test sample. The control accuracy of the movement distance of the moving slider (11) on the guide rail (2) is 0.1 mm.

9. The driving device for cyclic stretching and bending of polymer materials according to claim 1, characterized in that: The rotation speed of the driving end of the motor (16) is adjusted to control the stretching and bending cycle frequency of the test sample, and the control range of the cycle frequency is 0~5 Hz.

10. A test method for cyclic stretching and bending of polymer materials, based on the driving device according to any one of claims 1 to 8, characterized in that: The steps include: S1, determining the stroke of the moving slider according to the test deformation of the test sample, and setting the eccentricity of the eccentric wheel and the initial position of the moving slider on the guide rail according to the stroke; S2, determining the distance between the fixed end and the driving end of the sample according to the original length of the test sample, and adjusting the relative position of the first slider on the guide rail and the relative position of the second slider on the first slider in accordance with the distance; S3, fixing the two ends of the test sample to the sample fixing end clamping part and the sample driving end clamping part respectively; S4, set the motor speed according to the test frequency of the test sample. The motor drive end drives the eccentric wheel to rotate and drives the moving slider to move along the guide rail through the ball head connecting rod, so that the test sample undergoes periodic tensile / bending tests according to the set test deformation and test frequency.

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