A soft substrate coating adhesion performance testing device and characterization method

Abstract

This invention discloses a testing device and characterization method for the adhesion performance of coatings on soft substrates. The testing device includes a container, an airbag support, and an inflatable airbag disposed within the airbag support. The airbag support is closed on all sides, with mounting holes at the top and bottom for a tubular substrate to be tested to pass through. The inflatable airbag expands and deforms inward from the periphery of the airbag support to surround and compress the peripheral surface of the tubular substrate. The container contains a liquid medium that can fill between the inflatable airbag and the tubular substrate. This device can realistically simulate the actual application scenario of the tubular substrate under test, improving the realism and reliability of the test. The characterization method for the adhesion performance of the coating on the substrate obtained based on this device can use the adhesion performance characterization parameter K. f K characterizes the adhesion properties of the coating on the substrate. f It is unaffected by the size parameters of the device and the tubular substrate under test, and is suitable for evaluating various types of tubular substrates under test.

Description

Technical Field

[0001] The present invention relates to the field of mechanical performance testing of medical devices, and in particular to a soft substrate coating adhesion performance testing device, and also to a method for characterizing the adhesion performance of a soft substrate coating, using the above-mentioned soft substrate coating adhesion performance testing device. Background Art

[0002] Interventional medical consumables such as catheters and intravenous catheters have a wide range of users. In clinical practice, in order to alleviate patients' adverse medical experiences, a super-slip coating is generally attached to the surface of the catheter to increase its smoothness of movement in the human body.

[0003] Based on the above uses of interventional medical consumables, in order to ensure the reliability of the bonding between the soft substrate coating and the substrate of the interventional medical consumables during use, it is necessary to effectively evaluate the adhesion of the soft substrate coating.

[0004] At present, the following two methods are widely used for testing the adhesion of soft substrate coatings: the first method uses the cross-hatch method to characterize the quality grade of the coating, which requires direct destruction of the soft substrate coating itself and is not suitable for interventional medical consumables with uneven surfaces; the second method is to use a reciprocating motion wear test to test the adhesion of the coating. During the test, it is necessary to apply positive pressure to the interventional medical consumables and their soft substrate coatings through a plate-like fixture. If the interventional medical consumables are non-planar structures such as tubular structures, they will be subjected to large uneven deformation in the radial direction due to the positive pressure, and cannot simulate the actual contact state between the interventional medical consumables and the human body, and cannot obtain the actual adhesion of the soft substrate coating. Summary of the invention

[0005] The purpose of the present invention is to provide a soft substrate coating adhesion performance testing device, which can apply a uniform and stable positive pressure to the peripheral surface of the tubular substrate to be tested, and more realistically and reliably simulate the actual application scenario of the tubular substrate to be tested, so as to obtain the adhesion performance of the substrate outer coating on the surface of the tubular substrate to be tested. Another purpose of the present invention is to provide a method for characterizing the adhesion performance of a soft substrate coating, using the aforementioned soft substrate coating adhesion performance testing device.

[0006] To achieve the above-mentioned purpose, the present invention provides a soft substrate coating adhesion performance testing device, comprising a container, an airbag bracket fixed in the container and an inflatable airbag arranged in the airbag bracket; the airbag bracket is closed on all sides, and the top and bottom are respectively provided with mounting holes for the tubular substrate to be tested to pass through; any of the mounting holes is used to be separated from the tubular substrate to be tested so as to enable the tubular substrate to be tested to shuttle relative to the airbag bracket; the inflatable airbag expands and deforms inwardly from the circumference of the airbag bracket to surround and squeeze the circumferential surface of the tubular substrate to be tested; a liquid medium is provided in the container that can be filled between the inflatable airbag and the tubular substrate to be tested.

[0007] Preferably, the airbag support is in the shape of a circular tube; the inflatable airbag includes a cylindrical airbag membrane; the axial middle portion of the cylindrical airbag membrane is inserted into the airbag support; the axial ends of the cylindrical airbag membrane are rolled up and sealed and fixed to the outer sides of the axial ends of the airbag support.

[0008] Preferably, end covers are respectively provided at both axial ends of the airbag bracket; a first sealing gasket and a second sealing gasket are provided between any of the end covers and the axial end surface of the airbag bracket, which are tightly attached to the two sides of the cylindrical airbag membrane; an elastic ring is provided between any of the end covers and the outer peripheral surface of the axial end of the airbag bracket, which is tightened to the outer periphery of the cylindrical airbag membrane; and an annular groove is provided on the outer periphery of the airbag bracket for the elastic ring to be embedded and positioned.

[0009] Preferably, the container is a transparent cup with scales on the surface.

[0010] Preferably, the inflatable and deflable airbag is connected to an air pump and an air pressure gauge.

[0011] Preferably, it further comprises a tensile testing machine; the tensile testing machine has an upper clamping head for clamping and pulling the tubular matrix to be tested to shuttle relative to the airbag support.

[0012] Preferably, the top of the container is exposed; and a height adjustment device is provided at the bottom of the container.

[0013] The present invention also provides a method for characterizing the adhesion performance of a soft substrate coating, which is applied to the soft substrate coating adhesion performance testing device as described above, comprising:

[0014] S1: Clamp the inflatable and deflable airbag with internal pressure P on the circumference of the axial middle part of the tubular substrate to be tested with force F e Pull the tubular substrate to be tested to move at a uniform speed along the axial direction of the tubular substrate to be tested, and obtain the contact area πDL0 and the relative sliding distance L between the inflatable and deflable airbag and the tubular substrate to be tested;

[0015] S2: According to the force F e , the internal pressure P, the contact area to establish the adhesion performance characterization parameter K f ;in,

[0016] S3: Analyze the adhesion performance characterization parameter K f According to the variation law of the relative sliding distance L, the adhesion performance of the substrate outer coating of the tubular substrate to be tested is determined.

[0017] Preferably, the step S1 comprises:

[0018] S11: Inflate the inflatable and deflable airbag until the inflatable and deflable airbag is adjacent to the outer peripheral surface of the tubular substrate to be tested;

[0019] S12: adding a liquid medium into the container until the liquid level is lower than and close to the top surface of the inflatable and deflable airbag;

[0020] S13: Inflate the inflatable and deflable airbag until the internal pressure of the inflatable and deflable airbag is P, so that the inflatable and deflable airbag is in close contact with the outer peripheral surface of the tubular substrate to be tested.

[0021] Preferably, the adhesion performance in step S3 includes adhesion, adhesion uniformity and coating smoothness.

[0022] Compared with the above background technology, the soft substrate coating adhesion performance testing device provided by the present invention includes a container, an airbag bracket fixed in the container and an inflatable airbag arranged in the airbag bracket; wherein, a liquid medium is provided in the container that can be filled between the inflatable airbag and the tubular substrate to be tested.

[0023] In the soft substrate coating adhesion performance testing device, the airbag bracket is closed on all sides, and the top and bottom of the airbag bracket are respectively provided with mounting holes for the tubular substrate to be tested to pass through; the aperture of any mounting hole is larger than the radial dimension of the tubular substrate to be tested, so when the tubular substrate to be tested passes through the mounting holes at the top and bottom of the airbag bracket, only the inflated and deflable airbag surrounds and squeezes the peripheral side surface of the tubular substrate to be tested, and the mounting hole and the tubular substrate to be tested are separated from each other, and there is no force between the two.

[0024] When using the soft substrate coating adhesion performance testing device to test the adhesion performance of the substrate outer coating of the tubular substrate to be tested, first, the tubular substrate to be tested is inserted into the airbag bracket from the mounting holes at the top and bottom of the airbag bracket. The inflatable airbag in the airbag bracket is constrained by the airbag bracket and can only expand and deform inward from the circumference of the airbag bracket, and finally surrounds and squeezes the circumferential surface of the tubular substrate to be tested, that is, the outer tube wall, to complete the installation in the device; secondly, the tubular substrate to be tested is pulled to shuttle along the mounting hole, so that the tubular substrate to be tested moves relative to the inflatable airbag, and the substrate outer coating test operation of the tubular substrate to be tested is performed. Among them, the data obtained from the aforementioned substrate outer coating test operation can be used to analyze the characteristics of the substrate outer coating of the tubular substrate to be tested.

[0025] It can be seen that when the soft substrate coating adhesion performance test device provided by the present invention is used to perform substrate outer coating test operations, on the one hand, the way in which the inflatable and deflable airbag applies pressure to the tubular substrate to be tested is consistent with the tubular characteristics of the tubular substrate to be tested, and can apply annular pressure to the tubular substrate to be tested. The radial deformation of the tubular substrate to be tested is extremely small under the action of the confining pressure, and will not cause changes in the coating adhesion performance, thereby avoiding the influence of differences in test conditions and human factors on the test results; on the other hand, the soft substrate coating adhesion performance test device and the liquid medium therein can truly simulate the actual application scenario of the tubular substrate to be tested, and more flexibly and accurately test the adhesion performance of the substrate outer coating in different environments. In addition, the soft substrate coating adhesion performance test device can test, analyze and judge the adhesion performance of the substrate outer coating without destroying the substrate outer coating of the tubular substrate to be tested, thereby reducing the test cost.

[0026] The present invention also proposes a method for characterizing the adhesion performance of a soft substrate coating, which is suitable for characterizing the adhesion of a soft coating on a tubular soft substrate sample. The characterization result is not affected by the internal pressure P, the material and size specifications of the tubular substrate to be tested, and can be used to characterize whether the outer surface coating of the tubular substrate to be tested is evenly adhered or peeled off; it can also be used to characterize the coating smoothness of the outer surface coating under different coating processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0028] Figure 1 A schematic diagram of the structure of a soft substrate coating adhesion performance testing device provided by an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the partial structure of the soft substrate coating adhesion performance testing device provided by an embodiment of the present invention at the inflatable and deflable airbag and the airbag support;

[0030] Figure 3 This is a data analysis chart obtained after a test operation is performed using the soft substrate coating adhesion performance testing device provided by an embodiment of the present invention;

[0031] Figure 4 A schematic flow chart of a method for characterizing the adhesion performance of a soft substrate coating provided in an embodiment of the present invention.

[0032] Among them, 01-tubular matrix to be tested, 02-tensile testing machine, 1-container, 2-inflatable airbag, 3-airbag bracket, 4-air pump, 5-pressure gauge, 6-mounting hole, 7-end cover, 8-first sealing gasket, 9-second sealing gasket, 10-elastic ring, 11-height adjustment device, 111-adapter flange, 112-adjusting rod, 113-lower locking nut, 114-upper locking nut, 12-bracket bolt, 13-air pump seal, 14-air inlet nozzle, 15-pressure gauge seal. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0035] Please refer to Figures 1 to 4 , Figure 1 A schematic diagram of the structure of a soft substrate coating adhesion performance testing device provided by an embodiment of the present invention; Figure 2 A schematic diagram of the partial structure of the soft substrate coating adhesion performance testing device provided by an embodiment of the present invention at the inflatable and deflable airbag and the airbag support; Figure 3 This is a data analysis chart obtained after a test operation is performed using the soft substrate coating adhesion performance testing device provided by an embodiment of the present invention; Figure 4 A schematic flow chart of a method for characterizing the adhesion performance of a soft substrate coating provided in an embodiment of the present invention.

[0036] The present invention provides a soft substrate coating adhesion performance testing device, comprising a container 1, an inflatable and deflable airbag 2 arranged in the container 1, and a liquid medium arranged between the inflatable and deflable airbag 2 and a tubular substrate 01 to be tested.

[0037] The airbag bracket 3 is closed on all sides, and the top and bottom of the airbag bracket 3 are respectively provided with mounting holes 6 for the tubular substrate 01 to be tested to pass through. Therefore, when the tubular substrate 01 to be tested is pulled along the aforementioned mounting holes 6, it shuttles relative to the airbag bracket 3. The aperture of the aforementioned mounting hole 6 is larger than the diameter of the tubular substrate 01 to be tested. During the test process, the mounting hole 6 is separated from the surface of the tubular substrate 01 to be tested, avoiding the test structure that affects the adhesion performance of the substrate outer coating. Among them, the airbag bracket 3 can be suspended and positioned in the container 1 by the bracket bolts 12.

[0038] The inflatable airbag 2 is arranged in the airbag support 3. Under the shape and structure constraints of the airbag support 3, the inflatable airbag 2 expands and deforms from the circumference of the airbag support 3 to the inner center of the airbag support 3 when inflated. Once the inflatable airbag 2 expands to be close to the tubular substrate 01 to be tested, the inflatable airbag 2 surrounds and squeezes the circumferential surface of the tubular substrate 01 to be tested, that is, the outer tube wall, to achieve uniform annular pressure on the outer tube wall of the tubular substrate 01 to be tested.

[0039] Among them, it should be emphasized that the inflatable airbag 2 is arranged around the circumference of the tubular substrate 01 to be tested, which means that the outer surface of the inflatable airbag 2 is in close contact with the circumference of the tubular substrate 01 to be tested in all directions. For example, the shape of the inflatable airbag 2 can be similar to a life buoy, and the tubular substrate 01 to be tested is equivalent to a pipe column inserted from the center of the aforementioned life buoy.

[0040] The airbag support 3 and the inflatable airbag 2 are both arranged in the container 1. Therefore, when the tubular substrate 01 to be tested is inserted into the airbag support 3 and the inflatable airbag 2, it is also inserted into the container 1 containing the liquid medium. Therefore, the liquid medium in the container 1 can enter the airbag support 3 through the mounting hole 6 of the airbag support 3, and thus fill the space between the inflatable airbag 2 and the tubular substrate 01 to be tested. The aforementioned liquid medium can simulate liquids such as body fluids and tissue fluids in the human body, so that the soft substrate coating adhesion performance test device can truly simulate the actual application scenario of the tubular substrate 01 to be tested, thereby improving the authenticity and reliability of the test results of the device.

[0041] The soft substrate coating adhesion performance testing device provided by the present invention can be used to test the adhesion performance of the substrate outer coating of the tubular substrate 01 to be tested. During the test, the tubular substrate 01 to be tested is inserted into the container 1, the airbag bracket 3 and the inflatable airbag 2. The inflatable airbag 2 is arranged around the tubular substrate 01 to be tested, and after being inflated, it applies an actual balanced and stable pressure in any direction of the circumference of the tubular substrate 01 to be tested. The adhesion performance of the substrate outer coating is analyzed and judged by the force characteristics of the tubular substrate 01 to be tested under the aforementioned pressure.

[0042] The above is only a brief description of the use of the soft substrate coating adhesion performance testing device. As for the specific operation method and the analysis and judgment method of the adhesion performance of the substrate outer coating, please refer to the explanation and description of the characterization method of the adhesion performance of the substrate outer coating below.

[0043] The soft substrate coating adhesion performance testing device is used to test the adhesion performance of the substrate outer coating of the tubular substrate 01 to be tested. On the one hand, the way in which the inflatable and deflable airbag 2 applies pressure to the tubular substrate 01 to be tested is consistent with the tubular characteristics of the tubular substrate 01 to be tested, ensuring that the test results of the tubular substrate 01 to be tested are less affected by human factors, and can be applied to the tubular substrate 01 to be tested with a not very smooth surface; on the other hand, the inflatable and deflable airbag 2 and the liquid medium between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 can truly simulate the actual application scenario of the tubular substrate 01 to be tested. Obviously, by replacing the aforementioned liquid medium, it is possible to achieve a more flexible and accurate test of the adhesion performance of the substrate outer coating in different environments.

[0044] In addition, the soft substrate coating adhesion performance testing device can test, analyze and judge the adhesion performance of the substrate outer coating without destroying the substrate outer coating of the tubular substrate 01 to be tested, thereby reducing the testing cost.

[0045] The soft substrate coating adhesion performance testing device provided by the present invention is further described below in conjunction with the accompanying drawings and implementation examples.

[0046] In the soft substrate coating adhesion performance testing device provided by the present invention, the airbag bracket 3 can be set to be tubular, for example, the airbag bracket 3 includes a closed cylindrical surface and a circular plate fixed to the axial ends of the aforementioned cylindrical surface; a through mounting hole 6 is provided at the center of any circular plate. For the tubular airbag bracket 3, the inflatable airbag 2 can include a cylindrical airbag membrane, the axial middle part of the cylindrical airbag membrane is sleeved on the airbag bracket 3; the axial ends of the cylindrical airbag membrane are rolled up and sealed and fixed to the outer sides of the axial ends of the airbag bracket 3. At this time, a sealed cavity is formed between the circumferential inner surface of the airbag bracket 3 and the circumferential outer surface of the cylindrical airbag membrane. When the aforementioned sealed cavity is inflated, the cylindrical airbag membrane is constrained by the shape structure of the airbag bracket 3. Firstly, the cylindrical airbag membrane mainly expands in the direction close to the tubular substrate 01 to be tested, which is conducive to the subsequent operation. Secondly, the shape of the cylindrical airbag membrane after deformation can be controlled to ensure that the cylindrical airbag membrane applies pressure to the tube body test interval length L0 of the tubular substrate 01 to be tested.

[0047] Furthermore, the soft substrate coating adhesion performance testing device also includes end caps 7, such as an upper end cap and a lower end cap, which are fixedly sleeved on the axial ends of the airbag support 3. When the axial ends of the cylindrical airbag membrane are rolled over the outer sides of the axial ends of the airbag support 3, the two aforementioned end caps 7 are respectively sleeved on the axial ends of the airbag support 3, so that the axial ends of the cylindrical airbag membrane are respectively clamped and positioned between the airbag support 3 and any end cap 7.

[0048] In addition, since the working pressure in the sealing cavity is greater than the atmospheric pressure, in order to ensure the sealing performance of the sealing cavity between the airbag bracket 3 and the tubular airbag membrane and avoid slow air leakage of the sealing cavity, a first sealing gasket 8 and a second sealing gasket 9 are provided between any end cover 7 and the axial end face of the airbag bracket 3; an elastic ring 10 is provided between any end cover 7 and the outer peripheral surface of the axial end of the airbag bracket 3.

[0049] The shapes and sizes of the first sealing pad 8 and the second sealing pad 9 are close to the end face of the airbag support 3. In other words, if the end face of the airbag support 3 is annular, the first sealing pad 8 and the second sealing pad 9 are also annular and have sizes close to the end face size of the airbag support 3. The first sealing pad 8 and the second sealing pad 9 are closely attached to the two opposite sides of the cylindrical airbag membrane. For example, Figure 2 The upper end cover, the first sealing pad 8, the cylindrical airbag membrane, the second sealing pad 9 and the upper end surface of the airbag bracket 3 are arranged along the Figure 2 The vertical distribution is from top to bottom.

[0050] The elastic ring 10 is located at the circumferential side of the axial end of the airbag support 3. When the axial end of the cylindrical airbag membrane is rolled over the axial end of the airbag support 3, the elastic ring 10 tightens the axial end of the cylindrical airbag membrane to the axial end of the airbag support 3. In particular, the outer periphery of the axial end of the airbag support 3 may be provided with an annular groove, which is coaxially distributed with the airbag support 3. The elastic ring 10 may be embedded in the annular groove to improve the sealing and fixing effect of the elastic ring 10 on the cylindrical airbag membrane and the airbag support 3.

[0051] For the soft substrate coating adhesion performance testing device, one of the functions of the container 1 is to position and install the inflatable airbag 2 and constrain the deformation direction of the inflatable airbag 2 during the inflation and deflation process, ensuring that the inflatable airbag 2 is arranged around the tubular substrate 01 to be tested and applies pressure to the tubular substrate 01 to be tested; the second function of the container 1 is to contain liquid medium, providing a testing environment for the tubular substrate 01 to be tested that is closer to the specific operating environment of the tubular substrate 01 to be tested.

[0052] For the latter effect, when using the soft substrate coating adhesion performance testing device, the liquid medium needs to immerse the tube body test area of ​​the tubular substrate 01 to be tested. In order to facilitate the judgment of whether the liquid medium immerses the aforementioned tube body test area, a transparent cup body can be used as the aforementioned container 1.

[0053] In particular, the surface of the transparent cup body can be provided with scales distributed from the bottom of the cup to the cup mouth, which can not only assist the operator in determining the degree of immersion of the liquid medium in the aforementioned tube body test interval, but also assist the operator in obtaining the displacement of the tubular substrate 01 to be tested during the test process.

[0054] As for the inflatable airbag 2 of the soft substrate coating adhesion performance testing device, it can be connected to an air pump 4 and a pressure gauge 5; the air pump 4 is used to inflate and maintain the pressure of the inflatable airbag 2, and the pressure gauge 5 is used to measure the internal pressure of the inflatable airbag 2, and this internal pressure is used to analyze and judge the adhesion performance of the substrate outer coating.

[0055] In order to facilitate the observation of the movement of the tubular substrate 01 to be tested relative to the cylindrical airbag membrane, the above-mentioned airbag bracket 3 can be set as a transparent bracket, and a scale can also be set on the surface. In addition, in order to use the air pump 4 and the barometer 5 to connect the sealed cavity between the airbag bracket 3 and the cylindrical airbag membrane, a through threaded hole can be set on the surface of the airbag bracket 3, so that the air pump 4 and the barometer 5 can be sealed and installed on the airbag bracket 3 using the threaded hole. In order to improve the sealing performance of the air pump 4, the barometer 5 and the airbag bracket 3, the central axis of the threaded hole is perpendicular to the central axis of the airbag bracket 3, and the coaxiality of the matching surfaces of the air pump 4 and the barometer 5 with the threaded hole is improved. In addition, an air pump seal 13 can be set at the matching place between the air pump 4 and the threaded hole; a barometer seal 15 can be set at the matching place between the barometer 5 and the threaded hole.

[0056] The tubular airbag membrane can be made of a transparent polymer film with high elasticity, so as to simulate human skin, blood vessels or mucous membranes and other tissue materials. The barometer 5 can be a needle-type empty box barometer 5; the barometer 5 is connected to the sealed cavity between the airbag support 3 and the tubular airbag membrane through the air inlet nozzle 14. The air inlet nozzle 14 is a normally closed inflation port with a core needle structure in the center. After pressing the air inlet nozzle 14, a channel for air circulation is formed at the core needle.

[0057] When using the soft substrate coating adhesion performance testing device, it is necessary to make the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 produce relative movement when the inflatable and deflable airbag 2 surrounds and squeezes the peripheral surface of the tubular substrate 01 to be tested, and this state is often achieved by pulling the tubular substrate 01 to be tested from one axial end of the tubular substrate 01 to move. Therefore, the soft substrate coating adhesion performance testing device also includes a tensile testing machine 02 or is used in combination with a power device for applying tension to the tubular substrate 01 to be tested.

[0058] The upper clamp of the tensile testing machine 02 can clamp and fix the tubular substrate 01 to be tested, thereby pulling the tubular substrate 01 to be tested to move relative to the airbag support 3 .

[0059] In order to facilitate the operation of the tensile test machine 02, the soft substrate coating adhesion performance test device can use a container 1 with an open top and a closed bottom and sides, and the bottom of the aforementioned container 1 can be provided with a height adjustment device 11 for driving the container 1 to rise and fall. This height adjustment function of the height adjustment device 11 can meet the installation and testing requirements of the tubular substrates 01 to be tested of different lengths, ensuring that the tube body test interval and its movement range of the tubular substrate 01 to be tested meet the operating characteristics of the chuck of the tensile test machine 02.

[0060] The height adjustment device 11 includes components such as an adapter flange 111, an adjusting rod 112, an upper locking nut 114 and a lower locking nut 113 sleeved on the adjusting rod 112; the adapter flange 111 is used to connect to external equipment, such as the lower clamp of the tensile testing machine 02; the adjusting rod 112 cooperates with the upper locking nut 114 and the lower locking nut 113 to connect the container 1 and the adapter flange 111 and realize the distance adjustment between the container 1 and the adapter flange 111.

[0061] On the basis of the multiple embodiments provided above, the present invention further provides a method for characterizing the adhesion performance of a substrate outer coating, which is applied to the above soft substrate coating adhesion performance testing device.

[0062] The characterization method of the adhesion performance of the substrate outer coating includes:

[0063] S1: Clamp the inflatable and deflable airbag 2 with an internal pressure of P on the circumference of the axial middle of the tubular substrate 01 to be tested with a force F e Pull the tubular substrate 01 to be tested to move at a uniform speed along the axial direction of the tubular substrate 01 to be tested, and obtain the contact area πDL0 and the relative sliding distance L between the inflatable and deflable airbag 2 and the tubular substrate 01 to be tested;

[0064] S2: According to force F e , internal pressure P, contact area to establish adhesion performance characterization parameter K f ;in,

[0065] S3: Analysis of adhesion performance characterization parameter K f According to the variation law of the relative sliding distance L, the adhesion performance of the substrate outer coating of the tubular substrate 01 to be tested is determined.

[0066] The method for characterizing the adhesion performance of the substrate outer coating provided by the present invention evaluates the adhesion performance of the substrate outer coating of the tubular substrate 01 to be tested by testing, analyzing and judging.

[0067] First, the soft substrate coating adhesion performance testing device provided by the present invention is used to test the tubular substrate 01 to be tested. The test content includes the clamping of the tubular substrate 01 to be tested and the stretching of the tubular substrate 01 to be tested as described in the above step S1. In this process, the force Fe , internal pressure P, and the relative sliding distance L between the inflatable and deflable airbag 2 and the tubular substrate 01 to be tested. The relative sliding distance L is equal to the displacement L of the chuck of the tensile testing machine 02. e . At the same time, in order to reasonably and accurately control the contact area between the inflatable airbag 2 and the tubular substrate 01 to be tested, the characterization method uses the airbag bracket 3 of the soft substrate coating adhesion performance testing device to constrain the deformation direction and deformation degree of the inflatable airbag 2, so that the inflatable airbag 2 can be squeezed just in a specific area of ​​the tubular substrate 01 to be tested, so that the contact area between the inflatable airbag 2 and the tubular substrate 01 to be tested is represented by the area of ​​the aforementioned specific area. In short, the characterization method can pre-measure the dimensional parameters of the tubular substrate 01 to be tested, such as the outer tube diameter D of the tubular substrate 01 to be tested and the tube test interval length L0, before inflating the inflatable airbag 2, thereby calculating the contact area πDL0 between the inflatable airbag 2 and the tubular substrate 01 to be tested.

[0068] The tube body test interval length L0 refers to the length of the fitting portion between the inflatable and deflated airbag 2 and the tubular substrate 01 to be tested in the axial direction of the tubular substrate 01 to be tested; the outer tube diameter D and the tube body test interval length L0 are inherent parameters of the tubular substrate 01 to be tested; the internal pressure P can be a fixed value set artificially, which is a known quantity; or it can be a variable corresponding to the contact range between the inflatable and deflated airbag 2 and the tubular substrate 01 to be tested that satisfies the tube body test interval length L0. Force F e is the variable required to satisfy the uniform motion of the tubular substrate 01 to be tested during the test. e is the target measurement parameter in step S1.

[0069] With respect to the above internal pressure P, in order to more reasonably use the inflatable and deflable airbag 2 to apply confining pressure to the tubular substrate 01 to be tested, a pressure test can be conducted in advance with a standard sample of the same model and specification as the tubular substrate 01 to be tested before the formal test of the tubular substrate 01 to be tested, so as to obtain the matching relationship between the two parameters of the standard sample in terms of diameter and internal pressure, for example, the internal pressure P of the standard sample and the diameter of the standard sample when the inflatable and deflable airbag 2 and the standard sample are in effective contact. Among them, effective contact means that the inflatable and deflable airbag 2 and the standard sample are in full contact, with no gap between them.

[0070] Conducting a pressure test with a standard sample that is consistent with the model and specification of the tubular substrate 01 to be tested is conducive to simplifying the test and ensuring the test results. In other words, when formally testing the tubular substrate 01 to be tested, the operator inflates the inflatable and deflable airbag 2. During the inflation process, the operator can determine whether the inflatable and deflable airbag 2 and the tubular substrate 01 to be tested are in complete contact based on whether the internal air pressure of the inflatable and deflable airbag 2 reaches the recorded value in the aforementioned pressure test.

[0071] During the test, the tubular substrate 01 to be tested is inserted into the inflatable airbag 2 and suspended in the container 1. The total length L of the tested section of the tubular substrate 01 to be tested is z The relationship between the length of the pipe body test interval L0 is usually recommended to meet the following relationship: L z ≥2L0. In addition, after the inflatable and deflable airbag 2 is inflated, the inflatable and deflable airbag 2 may be tested for air leakage to ensure that the inflatable and deflable airbag 2 has no air leakage during the entire test process.

[0072] Secondly, the adhesion performance characterization parameter K is established based on the test data obtained from the above test. f , the adhesion performance characterization parameter K f It can be used to characterize and evaluate the adhesion performance of the substrate outer coating of the tubular substrate 01 to be tested.

[0073] The above adhesion performance characterization parameter K f The definition and calculation method of are as follows:

[0074] In step S1, in order to e The tubular substrate 01 to be tested is pulled to move along the axial direction of the tubular substrate 01 to be tested. The bottom of the container 1 can be fixed to the lower clamp of the tensile testing machine 02, and the upper end of the tubular substrate 01 to be tested is clamped to the upper clamp of the tensile testing machine 02. Then, the upper end of the tubular substrate 01 to be tested is pulled upward at a preset displacement rate. In this process, the force F of the tensile testing machine 02 is recorded. e and the displacement L of the chuck of the tensile testing machine 02 e .

[0075] For reference Figure 2 ,when Figure 2 When the bottom end of the tubular substrate 01 to be tested is flush with the bottom end of the inflatable and deflable airbag 2,

[0076] Le=Lz-La (1)

[0077] The process of the tensile testing machine 02 pulling the tubular substrate 01 to be tested can be divided into the following two stages:

[0078] The first stage: This stage is the start-up stage. Relative sliding will occur between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2. The F e It is the static friction force, and it enters the second stage after reaching the maximum value.

[0079] The second stage: In this stage, the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 slide relative to each other at a preset movement rate, and the bottom end of the tubular substrate 01 to be tested hangs in the container 1. In other words, at this time, the relative displacement of the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 is less than Lz and L a The difference between the two. In this stage, the tensile testing machine 02 collected F e is the sliding friction.

[0080] The second stage is the key application analysis stage of the characterization method of the adhesion performance of the substrate outer coating. In this stage, the friction force between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 is defined as F f During the experiment, the relative displacement between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 is L f , the stiffness coefficient of the tubular substrate 01 to be tested is K, and the tubular substrate 01 to be tested is F e The axial elastic deformation under the action is L x , then the above parameters have the following relationship:

[0081] F f =F e (2)

[0082] L e =L f +L x (3)

[0083]

[0084] At the same time, the effective contact length between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 along the axial direction of the tubular substrate 01 to be tested is defined as L a , when the internal pressure P of the inflatable and deflable airbag 2 is adjusted to a certain value, the inflatable and deflable airbag 2 is constrained by the tubular substrate 01 to be tested and the airbag support 3 at the same time, and the effective contact length between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 is L a is approximately equal to the length L0 of the test section of the inflatable and deflable airbag 2 along the tubular substrate 01 to be tested, that is, L a ≈L0, the length of the aforementioned tube test interval L0 can be accurately controlled by the airbag support 3.

[0085] Due to the axial deformation L of the tubular substrate 01 to be measured x Much smaller than the relative displacement L between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 f Based on this, L e To represent L f .

[0086] Since the tensile testing machine 02 pulls the tubular substrate 01 to be tested to move at a constant speed, F e represents the friction force F between the tubular substrate 01 and the inflatable and deflable airbag 2 to be tested f .

[0087] In addition, the original diameter of the tubular substrate 01 to be tested specifically refers to the outer diameter D. When the inflatable and deflable airbag 2 squeezes the tubular substrate 01 to be tested, the tubular substrate 01 to be tested is subjected to the confining pressure, and the deformation of the tubular substrate 01 to be tested along the radial direction is uniform and very small. Therefore, the outer diameter of the tubular substrate 01 to be tested after deformation can be regarded as d, and d≈D.

[0088] Based on the above analysis and setting, the coating adhesion condition on the surface of the tubular substrate 01 to be tested will be directly reflected in the friction force F f The distribution difference along the axial direction of the tubular substrate 01 to be tested, therefore, the friction force F between the tubular substrate 01 to be tested and the inflatable and deflable airbag 2 is f The following relationship exists between the internal pressure P of the inflatable and deflable airbag 2:

[0089] F f =F e =K f πDL0×P (5)

[0090] In formula (5), π, D, and L0 are constants, the internal pressure P is the reading of the barometer, and K f is the average sliding friction coefficient per unit area of ​​the tubular substrate 01 to be tested. Its size is related to the surface coating of the tubular substrate 01 to be tested, and has nothing to do with the internal pressure P, the material and nominal size of the tubular substrate 01 to be tested. Therefore, the above formula (5) can be transformed to obtain:

[0091]

[0092] Based on the above, the K of the tubular substrate 01 to be tested can be established. f -L e The curve is also K f -L curve. K established according to formula (6) f The value has nothing to do with the diameter of the tubular substrate 01 to be tested, the size of the soft substrate coating adhesion performance testing device, and the internal pressure P of the inflatable and deflable airbag 2, and can be directly used for the horizontal comparison of the test results of different samples or the same sample after different cycles.

[0093] Finally, based on the aforementioned adhesion performance characterization parameter K f Analyze and judge the adhesion performance of the substrate outer coating of the tubular substrate 01 to be tested.

[0094] Taking the tubular substrate 01 to be tested as a medical device tube such as a urinary catheter or an intravenous catheter as an example, the adhesion performance in the above step S3 may include the adhesion, adhesion uniformity and coating smoothness of the aforementioned medical device tube. Of course, the adhesion refers to the adhesion of the substrate outer coating on the surface of the medical device tube; the adhesion uniformity refers to the adhesion uniformity of the substrate outer coating on the surface of the medical device tube; and the coating smoothness refers to the smoothness of the substrate outer coating on the surface of the medical device tube.

[0095] Among them, for the same tubular substrate 01 to be measured, within the measurement range, if K f If the value is a constant, it indicates that the coating on the surface of the tubular substrate 01 to be tested is evenly adhered and the coating adhesion is consistent; K f The smaller the value, the smoother the coating.

[0096] For the same tubular substrate 01 to be tested, after N tests, if K f If the value of K increases as a whole, it indicates that the coating on the surface of the tubular substrate 01 to be tested has signs of falling off; f If there is a sudden change at a certain position, it indicates that the coating on the surface of the tubular substrate 01 to be tested that is currently in contact with the inflatable and deflable airbag 2 is unevenly adhered, or the coating is peeled off from the tubular substrate 01 to be tested due to poor adhesion of the coating.

[0097] For different tubular substrates 01 to be tested, it can be directly calculated based on K f The coating adhesion is compared with the K f Larger values ​​indicate poor coating smoothness or coating adhesion.

[0098] For reference Figure 3 , Figure 3 It is established based on the actual test data of three different tubular substrates 01 to be tested, namely, sample A, sample B and sample C.

[0099] according to Figure 3 It can be seen that the first test results show that in the first stage, the starting friction of sample A> the starting friction of sample B> the starting friction of sample C. In the second stage, the K f The values ​​are all constant, indicating that the coatings on the surfaces of the measurement areas of Samples A, B, and C are uniformly adhered. fA >K fB >K fC , which indicates that the smoothness of the substrate outer coating of sample A is poor, the smoothness of the substrate outer coating of sample B is second, and the smoothness of the substrate outer coating of sample C is the best.

[0100] After repeating the experiment N times, the N+1th test results of Sample A, Sample B, and Sample C were compared again and the second stage was analyzed with emphasis, and the following conclusions can be drawn:

[0101] K obtained by sample A in the N+1th test f The value is the same as the K obtained for sample A in the first test. f The values ​​are consistent, which shows that after N tests, the coating adhesion of sample A maintains the initial performance and the adhesion is good.

[0102] K obtained by sample B in the N+1th test f The value is compared with the K obtained by sample B in the first test. f The values ​​increased as a whole, which indicates that the substrate outer coating of sample B has changed. Compared with the substrate outer coating of sample A, the adhesion of the substrate outer coating of sample B is poor.

[0103] when Figure 3 When the horizontal axis value is M, the K of sample C f The value suddenly increases, which indicates that with the relative sliding of the sample C and the inflatable and deflable airbag 2, the coating of the test area of ​​the sample C suddenly becomes uneven. f The fluctuation position of the value along the horizontal axis can be used to analyze and determine the specific position of the defective coating on the surface of sample C.

[0104] During the above analysis, Figure 3 A horizontal comparison was made, and it can be seen that the K f The value remains unchanged, and the K of sample B f Value and K of sample C f The values ​​fluctuate, indicating that the coating adhesion of sample A is better than that of sample B and sample C.

[0105] In order to optimize the operation, based on the above embodiment, step S1 may include:

[0106] S11: Inflate the inflatable and deflable airbag 2 until the inflatable and deflable airbag 2 is close to the outer peripheral surface of the tubular substrate 01 to be tested;

[0107] S12: Add liquid medium into the container 1 until the liquid level is lower than and close to the top surface of the inflatable and deflable airbag 2;

[0108] S13: Inflate the inflatable and deflable airbag 2 until the internal pressure of the inflatable and deflable airbag 2 is P, so that the inflatable and deflable airbag 2 is in close contact with the outer peripheral surface of the tubular substrate 01 to be tested.

[0109] When the above three steps are performed in sequence, it can be ensured that the liquid level of the liquid medium in the container 1 is equal to or slightly higher than the top surface of the inflatable and deflable airbag 2, and it can also avoid splashing of the liquid medium due to rapid inflation of the inflatable and deflable airbag 2, or avoid that the liquid medium cannot be evenly filled between the inflatable and deflable airbag 2 and the tubular substrate 01 to be tested.

[0110] In summary, the soft substrate coating adhesion performance testing device provided by the present invention can apply annular pressure to the tubular substrate 01 to be tested, thereby forming a uniform annular positive pressure distribution effect on the circumferential surface of the tubular substrate 01 to be tested, which will not damage the surface coating of the tubular substrate 01 to be tested, and can also effectively avoid the shortcomings of unevenness and large deformation of soft base samples caused by flat plate experiments, and more realistically simulate the clinical use of the tubular substrate 01 to be tested. Based on the aforementioned soft substrate coating adhesion performance testing device, the present invention also proposes a characterization method for the adhesion of soft coatings on tubular soft substrate samples, and the characterization results are not affected by the internal pressure P and the specifications of the tubular substrate 01 to be tested, and can be used to characterize whether the surface coating of the tubular substrate 01 to be tested is uniformly attached, whether it is peeled off, etc.; it can also be used to characterize the coating smoothness of the surface coating under different coating processes, and can effectively avoid the shortcomings of flat plate experiments that the results cannot be compared horizontally due to different substrate sizes and positive pressures. The measurement result K of this characterization method f With displacement L e (L e =L z -L a ) can be used to quantitatively characterize and determine the adhesion of the coating on the tubular substrate 01 to be tested at a certain position in the test area. The test results are comprehensive and have good position directivity.

[0111] The above is a detailed introduction to the soft substrate coating adhesion performance testing device and characterization method provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A soft substrate coating adhesion performance testing device, characterized in that: The invention comprises a container (1), an airbag support (3) fixed in the container (1), and an inflatable airbag (2) arranged in the airbag support (3); the airbag support (3) is closed on all sides, and the top and bottom are respectively provided with mounting holes (6) for the tubular substrate (01) to be tested to pass through; any of the mounting holes (6) is used to be separated from the tubular substrate (01) to be tested so as to enable the tubular substrate (01) to be tested to pass through relative to the airbag support (3); the inflatable airbag (2) expands and deforms inwardly from the circumference of the airbag support (3) to surround and squeeze the circumferential surface of the tubular substrate (01) to be tested; a liquid medium is provided in the container and can be filled between the inflatable airbag (2) and the tubular substrate (01) to be tested; The container (1) is specifically a transparent cup body with scales on the surface; The inflatable and deflable air bag (2) is connected to an air pump (4) and an air pressure gauge (5).

2. The soft substrate coating adhesion performance testing device according to claim 1, characterized in that: The airbag support (3) is in the shape of a circular tube; the inflatable airbag (2) comprises a tubular airbag membrane; the axial middle portion of the tubular airbag membrane is sleeved on the airbag support (3); the axial ends of the tubular airbag membrane are rolled up and sealed and fixed to the outer sides of the axial ends of the airbag support (3).

3. The soft substrate coating adhesion performance testing device according to claim 2, characterized in that: The airbag bracket (3) is respectively sleeved with end covers (7) at both axial ends; a first sealing gasket (8) and a second sealing gasket (9) are provided between any of the end covers (7) and the axial end faces of the airbag bracket (3) and are tightly attached to the two sides of the tubular airbag membrane; an elastic ring (10) is provided between any of the end covers (7) and the outer peripheral surface of the axial end of the airbag bracket (3) and is tightened to the outer periphery of the tubular airbag membrane; and an annular groove is provided on the outer periphery of the airbag bracket (3) for the elastic ring (10) to be embedded and positioned.

4. The soft substrate coating adhesion performance testing device according to any one of claims 1 to 3, characterized in that: It also includes a tensile testing machine; the tensile testing machine has an upper clamping head for clamping and pulling the tubular matrix (01) to be tested to shuttle relative to the airbag support (3).

5. The soft substrate coating adhesion performance testing device according to claim 4, characterized in that: The top of the container (1) is exposed; the bottom of the container (1) is provided with a height adjustment device (11).

6. A method for characterizing the adhesion performance of a soft substrate coating, characterized in that: The soft substrate coating adhesion performance testing device as claimed in any one of claims 1 to 5 comprises: S1: Clamp the inflatable and deflable airbag (2) with an internal pressure of P on the circumference of the axial middle of the tubular substrate (01) to be tested with a force F e Pulling the tubular substrate (01) to be tested to move at a uniform speed along the axial direction of the tubular substrate (01) to be tested, and obtaining a contact area πDL0 and a relative sliding distance L between the inflatable and deflable airbag (2) and the tubular substrate (01) to be tested, wherein the outer diameter of the tubular substrate (01) to be tested is D and the length of the tube test interval is L0; S2: According to the force F e , the internal pressure P, the contact area to establish the adhesion performance characterization parameter K f ;in, S3: Analyze the adhesion performance characterization parameter K f According to the variation law of the relative sliding distance L, the adhesion performance of the substrate outer coating of the tubular substrate (01) to be tested is determined.

7. The method for characterizing the adhesion performance of a soft substrate coating according to claim 6, characterized in that: The S1 includes: S11: Inflate the inflatable and deflable airbag (2) until the inflatable and deflable airbag (2) is adjacent to the outer peripheral surface of the tubular substrate (01) to be tested; S12: adding a liquid medium into the container (1) until the liquid level is lower than and close to the top surface of the inflatable and deflable airbag (2); S13: Inflate the inflatable and deflable airbag (2) until the internal pressure of the inflatable and deflable airbag (2) reaches P, so that the inflatable and deflable airbag (2) is in close contact with the outer peripheral surface of the tubular substrate (01) to be tested.

8. The method for characterizing the adhesion performance of a soft substrate coating according to claim 7, characterized in that: The adhesion performance in S3 includes adhesion, adhesion uniformity and coating smoothness.

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