Thermal-state mechanical property detection method of composite film bag and test device of thermal-state mechanical property detection method

Abstract

The invention relates to the technical field of detection of soft plastic composite materials, in particular to a thermal-state mechanical property detection method of a composite film bag and a test device thereof, and the method comprises the following steps: S1, cutting five sample strips with the width of 15mm + / -1mm; s2, respectively clamping two ends of the stripped part of the sample strip on two clamps; s3, the humidifier is filled with tap water; s4, closing a sealing door of the heating box to seal the heating box body; s5, turning on a soaking fan; s6, setting the temperature of the heating box and heating the heating box; s7, a humidifier is turned on for humidification treatment; and S8, adjusting the state of the experimental environment in the heating box. According to the method and the device for detecting the thermal-state mechanical property of the composite film bag, the problems of peel strength, tensile strength and mechanical property in the prior art are solved; in the actual use process, detection equipment for detecting the tensile strength and the like cannot accurately judge whether the composite film bag for related food has the food safety risk of'layering 'or not after being subjected to water boiling sterilization at the temperature of 100 DEG C and cooking sterilization at the temperature of 100 DEG C or above.

Description

Technical Field

[0001] The present invention relates to the technical field of detection of soft plastic composite materials, and specifically to a method for detecting the thermal mechanical properties of composite film bags and a test device therefor. Background Art

[0002] In the field of detection of plastic composite flexible packaging, the detection method of peel strength all adopts the GB 8808-1988 Test Method for Peel of Flexible Composite Plastic Materials. To meet the long-term storage requirements of food, the food processing technology has made rapid progress; along with the development of food processing and storage technologies, higher requirements are put forward for food packaging, which promotes the synchronous development of the production process technology of food packaging. The concept of "flexible composite plastic materials" in the field of food packaging is refined into "plastic composite film and bag for food use". The peel strength detection technology of "plastic composite film and bag for food use" that develops synchronously with food processing and storage technologies cannot be completely synchronized with the relatively advanced "food processing and storage technologies" and the production process technology of "plastic composite film and bag for food use" that supports them. Therefore, exploring a scientific detection technology that matches the production process technology of contemporary relatively advanced "food processing and storage technologies" and "plastic composite film and bag for food use" that supports them to meet the needs of technological development has become the most urgent practical need at present.

[0003] However, the existing test device for detecting the thermal mechanical properties of composite film bags can only be used in an experimental environment of (23±2)°C and a relative humidity of (50±10)%, and cannot simulate the detection of the thermal mechanical properties of composite film bags under the environmental conditions of boiling at 100°C and steaming above 100°C. To solve this problem, a method for detecting the thermal mechanical properties of composite film bags and a test device therefor are provided. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for detecting the thermal mechanical properties of composite film bags and a test device therefor to solve the problems raised in the above background art. To achieve the above purpose, the present invention provides the following technical solutions: The method for detecting the thermal mechanical properties of composite film bags includes the following steps:

[0005] S1. Cut a specimen strip with a width of 15 mm±1 mm;

[0006] S2. Clamp both ends of the peeled part of the specimen strip on two clamps respectively;

[0007] S3. Install tap water in the humidifier;

[0008] S4. Close the sealed door of the heating box to seal the heating box body;

[0009] S5. Turn on the soaking fan;

[0010] S6. Set the temperature of the heating box and heat it.

[0011] S7. Turn on the humidifier for humidification treatment.

[0012] S8. Adjust the state of the experimental environment inside the heating box.

[0013] S9. Drive the fixture on the upper side to perform thermal peeling through the lifting component, and detect and record the peeling force through the tension sensor.

[0014] S10. Adjust the test environment jointly by the humidifier, hot fan and heating box to achieve the purpose of accurately judging whether there is a "delamination" food safety risk for the relevant food composite film bags after being sterilized by boiling at 100 °C and steaming at a temperature above 100 °C.

[0015] Preferably, in S1, it is also necessary to pre-peel 50 mm along the length direction of the specimen strip, and the specimen strip shall not have obvious damage.

[0016] Preferably, the water added to the humidifier in S3 is tap water, about 200 ml.

[0017] Preferably, the humidity in S8 needs to reach the saturation state.

[0018] The testing device for the thermomechanical properties of the composite film bag includes a heating box. A through hole is opened at the top end of the heating box. A lifting component is arranged at the top end of the heating box. The bottom end of the lifting component extends into the inner cavity of the heating box through the through hole. Fixed plates are arranged at the bottom end of the lifting component and the bottom end of the inner cavity of the heating box. Tension sensors are arranged on one side of the two fixed plates close to each other. A rack is arranged on one side of each tension sensor away from the fixed plate. A fixture is arranged in the inner cavity of each rack. A humidifier is arranged at the bottom end of the inner cavity of the heating box. A uniform hot fan is arranged at the top end of the inner cavity of the heating box. A temperature and humidity sensor is arranged at the rear side of the inner cavity of the heating box. A controller is arranged on one side of the outer wall of the heating box.

[0019] Preferably, a sealing door is hinged to the front end of the heating box. An observation window is fixedly embedded in the middle of the sealing door. A handle is arranged on the sealing door.

[0020] Preferably, the lifting component includes a bracket, a motor, a gear, a rack and a telescopic component. The bracket is arranged at the top end of the heating box. The motor is fixedly embedded in the middle of the bracket. The gear is fixedly sleeved on the output end of the motor. The rack is fixedly connected to the top end of one of the fixed plates and extends through the inner cavity of the through hole to the top end of the heating box to engage with the gear. The telescopic component is arranged between one of the fixed plates and the top end of the inner cavity of the heating box.

[0021] Preferably, the telescopic assembly includes a telescopic cylinder, a telescopic rod, a connection groove and a connection block. The telescopic cylinder is arranged at the top end of the fixed plate. The telescopic rod is slidably inserted into the inner cavity of the telescopic cylinder and fixedly connected to the top end of the inner cavity of the heating box. The connection groove is opened on one side of the inner wall of the telescopic cylinder. The connection block is slidably embedded in the inner cavity of the connection groove and fixedly connected to the outer wall of the telescopic rod. The inner cavity of the connection groove and the outer wall of the connection block are adapted to each other and are both in a dovetail shape.

[0022] Preferably, the fixture includes a lead screw, a knob, a slider, a clamping plate and a limiting assembly. One end of the lead screw is rotatably connected to the rear side of the inner cavity of the frame through a bearing. The other end of the lead screw extends to the front end of the frame and is fixedly connected to the knob. The two sliders are respectively screwed on the front and rear sides of the outer wall of the lead screw. The two clamping plates are respectively arranged at the tops of the two sliders. The limiting assembly is arranged at the bottom end of the inner cavity of the frame and is fixedly connected to the bottom ends of the two sliders. The threads on the front and rear sides of the outer wall of the lead screw are arranged oppositely. A plurality of anti-slip rods are arranged on the outer circumference of the knob.

[0023] Preferably, the limiting assembly includes a limiting groove and a limiting block. The limiting groove is opened at the bottom end of the inner cavity of the frame. The two limiting blocks are slidably embedded in the inner cavity of the limiting groove and are respectively fixedly connected to the bottom ends of the two sliders. The inner cavity of the limiting groove and the outer wall of the limiting block are adapted to each other and are both in a "T" shape.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] Cut a sample strip with a width of 15 mm ± 1 mm; clamp the two ends of the peeled part of the sample strip on the two fixtures respectively; in the humidifier, fill it with tap water; close the sealed door of the heating box to seal the heating box body; turn on the soaking fan; set the temperature of the heating box and heat it to the required temperature; turn on the humidifier for humidification treatment; adjust the state of the experimental environment inside the heating box; drive the fixture on the upper side to perform thermal peeling through the lifting assembly, and detect the peeling force through the tensile sensor and record the detection result; calculate the peeling strength based on the different sizes of the tensile forces detected by peeling the same length of the five sample strips, which solves the problem that the existing peeling strength detection equipment can only be used in an experimental environment of (23 ± 2) °C and a relative humidity of (50 ± 10)%, and cannot simulate the peeling strength detection under the environmental conditions of boiling at 100 °C and steaming above 100 °C.

[0026] Through the setting of the fixture, the clamping and fixing of the test strip can be realized. Through the setting of the lifting component, the fixing plate can drive the fixture installed thereon to pull the test strip. Through the tension sensor installed between the frame and the fixing plate, the tension generated during the pulling process of the test sample strip is detected. The peeling strength is calculated based on the different magnitudes of the tension detected when five test strips are peeled by the same length. Description of the Drawings

[0027] Figure 1 It is a schematic three-dimensional structure diagram of the method for detecting the thermomechanical properties of the composite film bag of the present invention and its test device;

[0028] Figure 2 It is a schematic structure diagram of the temperature and humidity sensor of the method for detecting the thermomechanical properties of the composite film bag of the present invention and its test device;

[0029] Figure 3 It is a main view sectional view of the telescopic cylinder of the method for detecting the thermomechanical properties of the composite film bag of the present invention and its test device;

[0030] Figure 4 It is a schematic structure diagram of the fixture of the method for detecting the thermomechanical properties of the composite film bag of the present invention and its test device;

[0031] Figure 5 It is a schematic structure diagram of the limit block of the method for detecting the thermomechanical properties of the composite film bag of the present invention and its test device;

[0032] Figure 6 It is a flow chart of the test method of the method for detecting the thermomechanical properties of the composite film bag of the present invention and its test device.

[0033] In the figure: 1. Heating box; 2. Sealing door; 3. Observation window; 4. Handle; 5. Bracket; 6. Through hole; 7. Fixing plate; 8. Frame; 9. Clamping plate; 10. Humidifier; 11. Soaking fan; 12. Temperature and humidity sensor; 13. Controller; 14. Lead screw; 15. Knob; 16. Slide block; 17. Limit groove; 18. Limit block; 19. Motor; 20. Gear; 21. Rack; 22. Telescopic cylinder; 23. Telescopic rod; 24. Connection groove; 25. Connection block. Detailed Embodiment

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

[0035] Please refer to Figures 1 to 6, the present invention provides a technical solution: a method for detecting the thermomechanical properties of a composite film bag, comprising the following steps:

[0036] S1. Cut a specimen strip with a width of 15 mm ± 1 mm;

[0037] S2. Clamp the two ends of the peeled part of the specimen strip on two fixtures respectively;

[0038] S3. Install tap water in the humidifier;

[0039] S4. Close the sealed door of the heating box to seal the heating box body;

[0040] S5. Turn on the soaking fan;

[0041] S6. Set the temperature of the heating box and heat it;

[0042] S7. Turn on the humidifier for humidification treatment; [[ID=ID=22]]

[0043] S8. Adjust the state of the experimental environment inside the heating box;

[0044] S9. Drive the fixture on the upper side to perform thermal peeling through the lifting component, and detect and record the peeling tension through a tension sensor;

[0045] S10. Adjust the test environment jointly through the humidifier, the heating fan and the heating box to achieve the purpose of accurately judging whether there is a "delamination" food safety risk for the relevant food composite film bag after being sterilized by boiling at 100 °C and steaming at a temperature above 100 °C;

[0046] It solves the problem that the existing detection equipment for peeling strength can only be carried out in an experimental environment of (23 ± 2) °C and a relative humidity of (50 ± 10)%, and cannot simulate the detection of peeling strength under the environmental conditions of boiling at 100 °C and steaming at a temperature above 100 °C.

[0047] In this embodiment, in S1, it is also necessary to pre-peel 50 mm along the length direction of the specimen strip, and the specimen strip shall not have obvious damage.

[0048] In this embodiment, the tap water added in the humidifier 10 in S3 is about 200 ml.

[0049] In this embodiment, the humidity in S8 needs to reach a saturated state.

[0050] Thermal mechanical property detection test device for composite film bags, including a heating box 1. A through hole 6 is provided at the top of the heating box 1. A lifting component is arranged at the top of the heating box 1. The bottom end of the lifting component extends into the inner cavity of the heating box 1 through the through hole 6. Fixed plates 7 are arranged at the bottom end of the lifting component and the bottom end of the inner cavity of the heating box 1. Tensile sensors are arranged on one side of each of the two fixed plates 7 close to each other. A frame 8 is arranged on one side of each tensile sensor away from the fixed plate 7. A clamp is arranged in the inner cavity of each frame 8. A humidifier 10 is arranged at the bottom end of the inner cavity of the heating box 1. A heat equalizing fan 11 is arranged at the top end of the inner cavity of the heating box 1. A temperature and humidity sensor 12 is arranged at the rear side of the inner cavity of the heating box 1. A controller 13 is arranged on one side of the outer wall of the heating box 1. Through the setting of the clamp, the clamping and fixing of the specimen strip can be realized. Through the setting of the lifting component, the fixed plate 7 can drive the clamp installed thereon to pull the specimen strip. The tensile force generated during the pulling process of the specimen strip is detected by the tensile sensor installed between the frame 8 and the fixed plate 7. The peeling strength is calculated based on the different magnitudes of the tensile forces detected when five specimen strips are peeled off the same length.

[0051] In this embodiment, a sealing door 2 is hinged to the front end of the heating box 1 to achieve the sealing of the heating box 1. An observation window 3 is fixedly embedded in the middle of the sealing door 2 to facilitate the observation of the peeling process. A handle 4 is arranged on the sealing door 2 to facilitate the opening and closing of the sealing door 2.

[0052] In this embodiment, the lifting component includes a bracket 5, a motor 19, a gear 20, a rack 21 and a telescopic component. The bracket 5 is arranged at the top of the heating box 1. The motor 19 is fixedly embedded in the middle of the bracket 5. The gear 20 is fixedly sleeved on the output end of the motor 19. The rack 21 is fixedly connected to the top end of one of the fixed plates 7 and extends through the inner cavity of the through hole 6 to the top of the heating box 1 and meshes with the gear 20. The telescopic component is arranged between one of the fixed plates 7 and the top end of the inner cavity of the heating box 1. Start the motor 19 to drive the gear 20 to rotate. Since the rack 21 meshes with the gear 20, when the gear 20 rotates, the rack 21 can drive the fixed plate 7, the tensile sensor and the clamp installed on the fixed plate 7 to slide upward to perform the peeling operation on the specimen strip.

[0053] In this embodiment, the telescopic assembly includes a telescopic cylinder 22, a telescopic rod 23, a connection groove 24, and a connection block 25. The telescopic cylinder 22 is disposed at the top end of the fixed plate 7. The telescopic rod 23 is slidably inserted into the inner cavity of the telescopic cylinder 22 and fixedly connected to the top end of the inner cavity of the heating box 1. The connection groove 24 is opened on one side of the inner wall of the telescopic cylinder 22. The connection block 25 is slidably embedded in the inner cavity of the connection groove 24 and fixedly connected to the outer wall of the telescopic rod 23. The inner cavity of the connection groove 24 and the outer wall of the connection block 25 are adapted to each other and are both in a dovetail shape. When the fixed plate 7 slides up and down, the telescopic rod 23 can slide up and down in the inner cavity of the telescopic cylinder 22. Under the combined action of the telescopic rod 23 and the telescopic cylinder 22, the fixed plate 7 can always slide up and down along a straight line. Under the combined action of the connection block 25 and the connection groove 24, one end of the telescopic rod 23 can always be kept inserted into the inner cavity of the telescopic cylinder 22.

[0054] In this embodiment, the fixture includes a lead screw 14, a knob 15, sliders 16, clamping plates 9, and a limiting assembly. One end of the lead screw 14 is rotatably connected to the rear side of the inner cavity of the frame 8 through a bearing. The other end of the lead screw 14 extends to the front end of the frame 8 and is fixedly connected to the knob 15. The two sliders 16 are respectively screwed on the front and rear sides of the outer wall of the lead screw 14. The two clamping plates 9 are respectively disposed at the top ends of the two sliders 16. The limiting assembly is disposed at the bottom end of the inner cavity of the frame 8 and is fixedly connected to the bottom ends of the two sliders 16. The threads on the front and rear sides of the outer wall of the lead screw 14 are arranged oppositely. A plurality of anti-slip rods are circumferentially arranged on the outer wall of the knob 15. By rotating the knob 15, the knob 15 drives the lead screw 14 to rotate, so that the relative threads on the left and right sides of the outer wall of the lead screw 14 generate relative thread rotation forces, causing the two sliders 16 to slide simultaneously towards the middle of the inner cavity of the frame 8 under the limiting action of the limiting groove 17 and the limiting block 18, and further clamping and fixing one end of the sample strip by the two clamping plates 9.

[0055] In this embodiment, the limiting assembly includes a limiting groove 17 and a limiting block 18. The limiting groove 17 is opened at the bottom end of the inner cavity of the frame 8. The two limiting blocks 18 are slidably embedded in the inner cavity of the limiting groove 17 and are respectively fixedly connected to the bottom ends of the two sliders 16. Under the combined action of the limiting groove 17 and the limiting block 18, the sliders 16 can be prevented from rotating with the lead screw 14 when the lead screw 14 rotates, improving the stability of the fixture during use. The inner cavity of the limiting groove 17 and the outer wall of the limiting block 18 are adapted to each other and are both in a "T" shape, enabling one end of the limiting block 18 to always be kept embedded in the inner cavity of the limiting groove 17, improving the stability of the limiting assembly during use.

[0056] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A method for detecting the thermomechanical properties of a composite film bag, characterized in that: It includes the following steps: S1. Cut a specimen strip with a width of 15 mm ± 1 mm; S2. Clamp both ends of the peeled part of the specimen strip on two fixtures respectively; S3. Fill the humidifier (10) with tap water; S4. Close the sealing door (2) of the heating chamber (1) to seal the heating chamber (1); S5. Turn on the heat equalizing fan (11); S6. Set the temperature of the heating chamber (1) and heat it; S7. Turn on the humidifier (10) for humidification treatment; S8. Adjust the state of the experimental environment inside the heating chamber (1); S9. Drive the fixture on the upper side to perform thermal peeling through the lifting assembly, and detect the peeling tension through the tension sensor and record the detection result; S10. Adjust the test environment jointly by the humidifier (10), the heat fan (11) and the heating chamber (1) to achieve the purpose of accurately judging whether there is a "delamination" food safety risk for the relevant food composite film bags after being sterilized by boiling at 100 °C and steaming sterilization above 100 °C.

2. The method for detecting the thermomechanical properties of the composite film bag according to claim 1, characterized in that: In the above S1, it is also necessary to pre-peel 50 mm along the length direction of the specimen strip, and the specimen strip shall not have obvious damage.

3. The method for detecting the thermomechanical properties of the composite film bag according to claim 1, characterized in that: In the above S3, the water added in the humidifier (10) is tap water, about 200 ml.

4. The method for detecting the thermomechanical properties of the composite film bag according to claim 1, wherein: In the above S8, the humidity needs to reach the saturation state.

5. Testing device for thermomechanical properties of composite film bags, characterized in that, It includes a heating chamber (1). A through hole (6) is opened at the top end of the heating chamber (1). A lifting assembly is arranged at the top end of the heating chamber (1). The bottom end of the lifting assembly extends into the inner cavity of the heating chamber (1) through the through hole (6). Fixing plates (7) are arranged at the bottom end of the lifting assembly and the bottom end of the inner cavity of the heating chamber (1). Tension sensors are arranged on one side of the two fixing plates (7) close to each other. A rack (8) is arranged on the side of each tension sensor away from the fixing plate (7). A fixture is arranged in the inner cavity of each rack (8). A humidifier (10) is arranged at the bottom end of the inner cavity of the heating chamber (1). A heat equalizing fan (11) is arranged at the top end of the inner cavity of the heating chamber (1). A temperature and humidity sensor (12) is arranged at the rear side of the inner cavity of the heating chamber (1). A controller (13) is arranged on one side of the outer wall of the heating chamber (1).

6. The testing device for the thermomechanical properties of the composite film bag according to claim 5, wherein: A sealing door (2) is hinged to the front end of the heating chamber (1). An observation window (3) is fixedly embedded in the middle of the sealing door (2). A handle (4) is arranged on the sealing door (2).

7. The testing device for the thermal mechanical properties of the composite film bag according to claim 5, wherein: The lifting assembly includes a bracket (5), a motor (19), a gear (20), a rack (21) and a telescopic assembly. The bracket (5) is arranged at the top end of the heating chamber (1). The motor (19) is fixedly embedded in the middle of the bracket (5). The gear (20) is fixedly sleeved on the output end of the motor (19). The rack (21) is fixedly connected to the top end of one of the fixing plates (7) and extends through the inner cavity of the through hole (6) to the top end of the heating chamber (1) to mesh with the gear (20). The telescopic assembly is arranged between one of the fixing plates (7) and the top end of the inner cavity of the heating chamber (1).

8. The testing device for the thermal mechanical properties of the composite film bag according to claim 7, characterized in that: The telescopic assembly includes a telescopic cylinder (22), a telescopic rod (23), a connection groove (24) and a connection block (25). The telescopic cylinder (22) is arranged at the top end of the fixed plate (7). The telescopic rod (23) is slidably inserted into the inner cavity of the telescopic cylinder (22) and fixedly connected to the top end of the inner cavity of the heating box (1). The connection groove (24) is opened on one side of the inner wall of the telescopic cylinder (22). The connection block (25) is slidably embedded in the inner cavity of the connection groove (24) and fixedly connected to the outer wall of the telescopic rod (23). The inner cavity of the connection groove (24) and the outer wall of the connection block (25) are adapted to each other and are both in a dovetail shape.

9. The testing device for the thermomechanical properties of the composite film bag according to claim 5, characterized in that: The fixture includes a lead screw (14), a knob (15), a slider (16), a clamping plate (9) and a limiting assembly. One end of the lead screw (14) is rotatably connected to the rear side of the inner cavity of the frame (8) through a bearing. The other end of the lead screw (14) extends to the front end of the frame (8) and is fixedly connected to the knob (15). The two sliders (16) are respectively screwed on the front and rear sides of the outer wall of the lead screw (14). The two clamping plates (9) are respectively arranged at the top ends of the two sliders (16). The limiting assembly is arranged at the bottom end of the inner cavity of the frame (8) and is fixedly connected to the bottom ends of the two sliders (16). The threads on the front and rear sides of the outer wall of the lead screw (14) are arranged oppositely. A plurality of anti-slip rods are arranged on the circumferential wall of the knob (15).

10. The testing device for the thermomechanical properties of the composite film bag according to claim 9, characterized in that: The limiting assembly includes a limiting groove (17) and a limiting block (18). The limiting groove (17) is opened at the bottom end of the inner cavity of the frame (8). The two limiting blocks (18) are slidably embedded in the inner cavity of the limiting groove (17) and are respectively fixedly connected to the bottom ends of the two sliders (16). The inner cavity of the limiting groove (17) and the outer wall of the limiting block (18) are adapted to each other and are both in a "T" shape.

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