Solid contact angle measuring device considering surface modification and measuring method thereof

Abstract

The invention provides a solid contact angle measuring device considering surface modification and a measuring method thereof.The solid contact angle measuring device comprises a tray, a drying assembly is arranged above the tray, a clamping groove corresponding to the drying assembly is formed in the center of the tray, buckles and a titration assembly are connected in the clamping groove, the titration assembly comprises a supporting rod, and a sliding groove is formed in the supporting rod; a sliding block is slidably connected into the sliding groove, a burette is connected to the bottom end of the sliding block, and the sliding block is connected with a stroke assembly in a penetrating manner; one end of the contact angle measuring instrument is connected with a support, the contact angle measuring instrument is used for measuring a sample fixed above the tray, and when the sample is subjected to modification, drying and measurement integrated contact angle measurement, not only can the influence of different modification conditions on a contact angle be measured, but also the measurement accuracy is improved. And the influence of environment temperature and humidity change on the sample in step-by-step operation can be avoided, so that the measurement period of the contact angle is remarkably shortened, and the measurement efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of material surface performance testing, and particularly to a solid contact angle measuring device and a measuring method considering surface modification. Background Art

[0002] In the field of materials science, the surface performance of materials plays a crucial role in their practical applications. As the interface directly contacting the external environment, the material surface is constantly faced with various complex factors. For example, in a humid environment, the surface of metal materials is prone to corrosion, leading to a decline in their mechanical properties; in a high-temperature environment, the material surface may be oxidized, changing its original physical and chemical properties; and in some occasions with frequent friction, the material surface will be worn, affecting its service life.

[0003] In order to improve the surface performance of materials, changing the surface composition of materials through chemical reagents has become a core technical means. This method can endow the material surface with various special abilities, such as hydrophilicity or hydrophobicity, which is of great significance for the applications of materials in the fields of waterproofing, anti-fouling, biomedicine, etc. Materials with hydrophobic surfaces can be used to manufacture waterproof clothing, self-cleaning glass and other products; while hydrophilic surfaces contribute to the good combination of biomaterials and biological tissues. In addition, surface modification can also enhance the corrosion resistance of materials, extend the service life of materials in harsh environments, and endow materials with self-cleaning ability, reducing the adhesion of dust and dirt on their surfaces.

[0004] Wettability, as one of the key indicators for measuring the surface performance of materials, is usually characterized by the contact angle. The contact angle refers to the angle between the gas-liquid interface and the solid-liquid interface at the three-phase intersection point of gas, liquid and solid. It intuitively reflects the wetting degree of the liquid on the solid surface. However, the existing contact angle measurement methods have many drawbacks. The current measurement steps are relatively scattered. During the whole measurement process, the sample often needs to be transferred multiple times between multiple different devices or environments, which not only greatly reduces the measurement efficiency and increases the time cost required for measurement, but also in each transfer process, the sample has a greater chance of being affected by external pollutants, increasing the degree of sample pollution. At the same time, since it is difficult to keep the environmental temperature and humidity constant in different measurement links, this fluctuation will have a significant impact on the measurement accuracy.

[0005] In summary, the existing contact angle measurement technologies have obvious deficiencies in terms of efficiency and accuracy. There is an urgent need to design a contact angle measuring device that can integrate multiple links such as sample modification, drying, and measurement to effectively solve the above problems, improve the efficiency and accuracy of contact angle measurement, and provide more reliable technical support for the research and optimization of material surface performance. Summary of the Invention

[0006] To overcome the existing problems, an embodiment of the present application provides a solid contact angle measuring device and a measuring method considering surface modification. When performing integrated contact angle measurement of sample modification, drying, and measurement, it can not only measure the influence of different modification conditions on the contact angle, but also avoid the influence of environmental temperature and humidity changes on the sample during step-by-step operations, significantly shortening the measurement cycle of the contact angle and improving the measurement efficiency.

[0007] The technical solution adopted by the embodiment of the present application to solve its technical problems is:

[0008] A solid contact angle measuring device considering surface modification of the present application includes:

[0009] A tray, above which a drying component is provided. At the center position of the tray, there is a card slot corresponding to the drying component. The card slot is evenly divided into three rectangular parts, and each rectangular part is connected with a buckle. The buckle can slide inside the card slot, move and fix the buckle by means of magnetism, for fixing the sample to be measured. One end of the buckle is provided with a leakage hole, and the leakage hole is connected with a drain pipe, and the liquid is introduced into the waste liquid bucket through the drain pipe;

[0010] The drying component includes a drying box connected to the tray. Two rows of fans are embedded in the top of the drying box. Heaters are connected to both sides inside the drying box. The bottom of the drying box is not closed. In this way, when the drying box rotates through a rotating ring, it can be connected to the tray. There is a partition inside. Through the setting of the partition, the space inside the tray can be separated. A groove is opened at the top of the drying box inside the two rows of fans. Through the setting of the groove, when the burette at the top titrates the liquid, the titrated liquid can fall into the tray from inside the groove;

[0011] The titration component includes a support rod, a chute is opened inside the support rod, a slider is slidably connected inside the chute, the bottom end of the slider is connected with a burette, and the slider is connected with a stroke component through connection;

[0012] And, a contact angle measuring instrument, one end of the contact angle measuring instrument is connected with a bracket, the bracket is of an L-shaped structure, and one end of the bracket away from the contact angle measuring instrument is installed at one end of the tray, for measuring the sample fixed above the tray.

[0013] Preferably, a support frame is provided at one end of the tray away from the support. The design of the support frame enables each component to work together to form a complete contact angle measurement system. Above the tray, the support frame is connected to a rotating ring connected to the drying component. The rotating ring is fixedly connected to the drying component and can rotate around the support frame to drive the drying component to rotate. A fixed ring is provided at the bottom end of the rotating ring for connecting to the lifting cylinder, and the bottom end of the support frame is connected to a bottom plate;

[0014] Wherein, a drain pipe is connected to the corresponding position of the leak hole at the bottom end of the tray, and the bottom end of the drain pipe is connected to a waste liquid bucket.

[0015] Preferably, the travel component includes a servo motor connected to the support rod. The output end of the servo motor is connected to a lead screw, and the lead screw is threadedly connected to the slider. A baffle is provided at the other end of the lead screw. The servo motor is connected to the control system, and the operation of the servo motor can be controlled through the control system, so as to drive the burette to move on the upper surface of the support rod;

[0016] Wherein, a collar is provided at the connection between the support rod and the support frame. A stepping motor is provided at the top end of the support frame, and a limiting groove is provided at the intersection of the support frame and the titration component. A threaded rod is provided inside the limiting groove, and the titration component is connected to the threaded rod inside the limiting groove. When the stepping motor operates, it drives the titration component to move up and down inside the limiting groove.

[0017] Preferably, a distilled water container and three modified liquid containers are provided at one end of the cross bar located on the support frame. The distilled water container, the three modified liquid containers, and the cross bar are all detachable structures;

[0018] Wherein, connecting pipes are connected to the bottom ends of the distilled water container and the modified liquid containers, and valves are provided inside the connecting pipes to control the flow of the solutions inside the distilled water container and the modified liquid containers. By providing valves on the outer wall of the connecting pipes, the valves inside different connecting pipes can be controlled to control the flow of liquids in different containers.

[0019] Preferably, a push-pull plate is provided at one end of the drying box located on the contact angle measuring instrument. A through hole runs through the bottom end of the heater inside the drying box, and the through hole is connected to the connecting pipes at the bottom ends of the distilled water container and the three modified liquid containers. A rectangular hole is provided at one end of the drying box where the push-pull plate is located. During the drying process, the push-pull plate is in a closed state. When measurement is required through the contact angle measuring instrument, the push-pull plate and the partition are opened, so that the contact angle measuring instrument can take pictures of the internal sample through the rectangular hole.

[0020] Meanwhile, the present application also provides a method for measuring the solid contact angle considering surface modification, including the following steps:

[0021] Step 1: Fix the measured sample on the buckle of the tray.

[0022] Step 2: Rotate and move the drying component so that the drying component is facing and aligned with the card slot of the tray, and then set the temperature of the drying component.

[0023] Step 3: Open the valve of the connecting pipe at the bottom of the modification liquid container, connect the modification liquid container to the drying component, immerse the sample with the modification liquid, and close the valve after reaching the set immersion volume.

[0024] Step 4: After the sample reaches the modification time, open the switch of the drain pipe to make the modification liquid flow into the waste liquid bucket.

[0025] Step 5: Close the valve of the modification liquid container, open the valve of the connecting pipe at the bottom of the distilled water container, connect the distilled water container to the drying component, rinse the test sample with distilled water, and close the valve after rinsing.

[0026] Step 6: Turn on the fan of the drying component and set the drying temperature through the heater to dry the sample.

[0027] Step 7: After the sample is dried, turn on the contact angle measuring instrument, open the push-pull plate and the partition plate so that the sample is photographed by the high-speed camera.

[0028] Step 8: Move the buckle of the sample under test within the range of the high-speed camera, move the other buckles outside the range, use the control system to control the servo motor to drive the burette to move above the sample, ensure that the liquid outlet of the burette needle is within the range of the high-speed camera shooting of the sample surface, and drive the titration component to move in the vertical direction under the movement of the stepping motor.

[0029] Step 9: Adjust the titrant in the burette to form a liquid drop about to drip at the burette needle, move the burette down until the liquid drop falls on the sample surface and leaves, presenting a certain angle on the sample surface.

[0030] Step 10: Use the contact angle measuring instrument to photograph the whole process of the titrant contacting the sample surface, form hundreds of photographed images, select clear and stable images from them, and use software to measure and calculate the contact angle.

[0031] Step 11: Repeat the above steps to measure the contact angle of the next group of sample surfaces.

[0032] Step 12: Measure and record the contact angle of the sample surface after modification with the modification liquid, and sort out, analyze and summarize the measured contact angle data.

[0033] Preferably, the measurement and calculation of the contact angle adopt the Young-Laplace equation for droplet shape analysis. The calculation formula for the contact angle θ is as follows:

[0034]

[0035] where γsv is the solid-gas interfacial tension, γs is the solid-liquid interfacial tension, and γlv is the liquid-gas interfacial tension, which is used to describe the contact angle of the droplet on the solid surface and reflects the tension balance relationship of the solid-liquid-gas three-phase interface.

[0036] Preferably, the type, concentration, volume, and soaking time of the modification liquid are set according to experimental requirements. The relationship between the concentration C of the modification liquid and the contact angle θ can be fitted by the following empirical formula:

[0037] θ = a*C + b

[0038] where a and b are fitting parameters, and C is the concentration of the modification liquid. Through linear fitting, the influence law of the modification liquid concentration on the contact angle can be obtained.

[0039] Preferably, the relationship between the drying temperature T and the drying time t is optimized by the following formula:

[0040]

[0041] where k is the drying rate constant and T0 is the ambient temperature, which can optimize the drying temperature and time to ensure that the sample is not affected by the external environment during the drying process.

[0042] Preferably, the contact angle measuring instrument captures the contact process of the droplet on the sample surface through a high-speed camera. The contact angle θ of the droplet is calculated by the following geometric formula:

[0043]

[0044] where h is the height of the droplet and r is the radius of the bottom of the droplet. Through the height and bottom radius of the droplet, the contact angle can be directly calculated, which is applicable to the case where the droplet shape is relatively regular.

[0045] The advantages of the embodiments of the present application are as follows:

[0046] 1. When performing integrated contact angle measurement of sample modification, drying, and determination, it can not only measure the influence of different modification conditions on the contact angle, but also avoid the influence of environmental temperature and humidity changes on the sample during the step-by-step operation, significantly shortening the measurement cycle of the contact angle, improving the measurement efficiency, and reducing the material loss.

[0047] 2. The sample processing and measurement are completed in a relatively stable environment. The temperature and humidity can be precisely controlled by other devices such as a drying component, avoiding the interference of environmental factors on the surface state of the sample, greatly improving the measurement accuracy, and providing more reliable data support for the research on the surface properties of materials.

[0048] 3. The unique design of the tray card slot can accommodate multiple samples at the same time, and fix samples with different shapes and sizes through buckles. Whether it is regular block materials or irregular materials such as films and fibers, they can be stably fixed. At the same time, the internal partition of the drying component and the connection with various liquid containers enable the treatment of multiple samples under different modification conditions simultaneously, greatly enhancing the versatility and flexibility of the device, meeting diverse research needs, and being widely applicable to the research on the surface properties of materials in different fields. Brief Description of the Drawings

[0049] The present invention will be further described below in conjunction with the drawings and embodiments.

[0050] Figure 1 It is a schematic diagram of the overall structure of the solid contact angle measuring device considering surface modification of the present invention;

[0051] Figure 2 It is a schematic diagram of the overall structure of the connection between the support frame and the waste liquid bucket in the solid contact angle measuring device considering surface modification of the present invention;

[0052] Figure 3 It is a schematic diagram of the overall structure of the tray in the solid contact angle measuring device considering surface modification of the present invention;

[0053] Figure 4 It is a schematic diagram of the overall structure of the drying component push-pull plate in the closed state in the solid contact angle measuring device considering surface modification of the present invention;

[0054] Figure 5 It is a schematic diagram of the overall structure of the drying component push-pull plate in the open state in the solid contact angle measuring device considering surface modification of the present invention;

[0055] Figure 6 It is a schematic diagram of the overall structure of the titration component in the solid contact angle measuring device considering surface modification of the present invention.

[0056] Main Reference Numeral Descriptions:

[0057] 1. Support frame; 2. Drying component; 21. Drying box; 22. Heater; 23. Fan; 24. Groove; 25. Push-pull plate; 26. Partition board; 27. Through hole; 3. Rotating ring; 4. Bottom plate; 5. Titration component; 51. Collar; 52. Slide groove; 53. Servo motor; 54. Support rod; 55. Slide block; 56. Burette; 57. Lead screw; 58. Baffle; 6. Tray; 7. Bracket; 8. Connecting pipe; 9. Contact angle measuring instrument; 10. Waste liquid bucket; 11. Drain pipe; 12. Distilled water container; 13. Modified liquid container; 14. Limit groove; 15. Cross bar; 16. Card slot; 17. Leak hole; 18. Snap fastener; 19. Stepper motor; 20. Lifting cylinder; 28. Fixed ring. Detailed implementation manners

[0058] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying 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 efforts shall fall within the protection scope of the present invention. In addition, for convenience of description below, the "upper", "lower", "left", "right", etc. cited are consistent with the upper, lower, left, right, etc. of the accompanying drawings themselves. The "first", "second", etc. in the following text are for descriptive distinction and have no other special meanings.

[0059] By providing a solid contact angle measurement device and a measurement method considering surface modification in the embodiments of the present application, the problems in the prior art are solved. When performing integrated contact angle measurement of sample modification, drying, and measurement, it can not only measure the influence of different modification conditions on the contact angle, but also avoid the influence of environmental temperature and humidity changes on the sample during step-by-step operations, significantly shortening the measurement cycle of the contact angle, improving the measurement efficiency, and reducing material loss; sample processing and measurement are completed in a relatively stable environment, and the temperature and humidity can be precisely controlled by other devices such as the drying component, avoiding interference from environmental factors on the surface state of the sample, greatly improving the measurement accuracy, and providing more reliable data support for the research of material surface properties; the unique design of the tray card slot can accommodate multiple samples at the same time, and different-shaped and -sized samples can be fixed by snap fasteners. Whether it is regular block materials or irregular films, fibers and other materials, they can be stably fixed. At the same time, the internal partition of the drying component and the connection with multiple liquid containers enable different modification conditions to be applied to multiple samples simultaneously, greatly enhancing the versatility and flexibility of the device, meeting diverse research needs, and being widely applicable to the research of material surface properties in different fields.

[0060] The technical solutions in the embodiments of the present application are as follows to solve the above problems:

[0061] Embodiment

[0062] This embodiment provides a specific structure of a solid contact angle measuring device considering surface modification, as Figure 1-6 shown, including:

[0063] A tray 6, above which a drying component 2 is provided. At the center of the tray 6, there is a card slot 16 corresponding to the drying component 2. The card slot 16 is evenly divided into three rectangular parts, and each rectangular part is connected with a buckle 18. The buckle 18 can slide inside the card slot 16 for fixing the sample to be measured. One end of the buckle 18 is penetrated with a leakage hole 17, and the leakage hole 17 is connected to a drain pipe 11. The liquid is introduced into the waste liquid bucket 10 through the drain pipe 11;

[0064] The drying component 2 includes a drying box 21 connected to the tray 6. Two rows of fans 23 are embedded at the top of the drying box 21. Heaters 22 are connected to both sides inside the drying box 21. The bottom of the drying box 21 is not closed. In this way, when the drying box 21 rotates through the rotating ring 3, it can be connected to the tray 6. There is a partition 26 inside. Through the setting of the partition 26, the space inside the tray 6 can be separated. At the top of the drying box 21, a groove 24 is opened inside the two rows of fans 23. Through the setting of the groove 24, when the burette 56 at the top titrates the liquid, the titrated liquid can fall into the tray 6 from inside the groove 24;

[0065] The titration component 5 includes a support rod 54. A chute 52 is opened inside the support rod 54. A slider 55 is slidably connected inside the chute 52. The bottom end of the slider 55 is connected with a burette 56. The slider 55 is connected with a stroke component through penetration;

[0066] And, a contact angle measuring instrument 9. One end of the contact angle measuring instrument 9 is connected with a bracket 7. The bracket 7 is of an L-shaped structure. The end of the bracket 7 away from the contact angle measuring instrument 9 is installed at one end of the tray 6 for measuring the sample fixed above the tray 6.

[0067] At one end of the tray 6 away from the bracket 7, there is a support frame 1. The design of the support frame 1 enables each component to work together to form a complete contact angle measuring system. Above the tray 6, the support frame 1 is connected with a rotating ring 3 connected to the drying component 2. The rotating ring 3 is fixedly connected with the drying component 2. The rotating ring 3 can rotate around the support frame 1 to drive the drying component 2 to rotate. At the bottom end of the rotating ring 3, there is a fixed ring 28 for connecting with a lifting cylinder 20. When the drying component 2 moves above the tray 6, at this time, the lifting cylinder 20 operates to drive the tray 6 to move upward and be tightly clamped with the drying component 2. The bottom end of the support frame 1 is connected with a bottom plate 4;

[0068] Among them, a drain pipe 11 is connected to the bottom end of the tray 6 at the position corresponding to the leakage hole 17, and the bottom end of the drain pipe 11 is connected to a waste liquid bucket 10.

[0069] The travel assembly includes a servo motor 53 connected to the support rod 54. The output end of the servo motor 53 is connected to a lead screw 57. The lead screw 57 is rotationally connected to a slider 55. A baffle 58 is provided at the other end of the lead screw 57. The servo motor 53 is connected to the control system. The operation of the servo motor 53 can be controlled through the control system, so as to drive the burette 56 to move on the upper surface of the support rod 54.

[0070] Among them, a collar 51 is provided at the connection between the support rod 54 and the support frame 1. A stepping motor 19 is provided at the top end of the support frame 1. A limit groove 14 is provided at the intersection of the support frame 1 and the titration assembly 5. When the stepping motor 19 operates, it drives the titration assembly 5 to move up and down inside the limit groove 14.

[0071] A distilled water container 12 and three modified liquid containers 13 are provided at one end of the cross bar 15 on the support frame 1. The distilled water container 12, the three modified liquid containers 13 and the cross bar 15 are all detachable structures.

[0072] Among them, a connecting pipe 8 is connected to the bottom end of both the distilled water container 12 and the modified liquid container 13. Valves are provided inside the connecting pipe 8 to control the flow of the solution inside the distilled water container 12 and the modified liquid container 13. By providing valves on the outer wall of the connecting pipe 8, the valves inside different connecting pipes 8 can be controlled to control the flow of liquid in different containers.

[0073] A push-pull plate 25 is provided at one end of the drying oven 21 at the contact angle measuring instrument 9. A through hole 27 runs through the bottom end of the heater 22 inside the drying oven 21. The through hole 27 is connected to the connecting pipe 8 at the bottom end of the distilled water container 12 and the three modified liquid containers 13. A rectangular hole is opened at one end of the drying oven 21 where the push-pull plate 25 is located. During the drying process, the push-pull plate 25 is in the closed state. When measurement is required through the contact angle measuring instrument 9, the push-pull plate 25 and the partition 26 are opened, so that the contact angle measuring instrument 9 can take pictures of the internal sample through the rectangular hole.

[0074] Based on the above considerations, the measurement method of the solid contact angle measurement device for surface modification includes the following steps:

[0075] Step 1: Fix the sample to be measured on the buckle 18 of the tray 6.

[0076] Step 2: Rotate and move the drying assembly 2 to make the drying assembly 2 face and align with the card slot 16 of the tray 6 and connect them. Then set the temperature of the drying assembly 2.

[0077] Step 3: Open the valve of the connecting pipe 8 at the bottom end of the modification liquid container 13, connect the modification liquid container 13 to the drying assembly 2, soak the sample with the modification liquid, and close the valve after reaching the set soaking volume;

[0078] Step 4: After the sample reaches the modification time, open the switch of the drain pipe 11 to allow the modification liquid to flow into the waste liquid bucket 10;

[0079] Step 5: Close the valve of the modification liquid container 13, open the valve of the connecting pipe 8 at the bottom end of the distilled water container 12, connect the distilled water container 12 to the drying assembly 2, rinse the test sample with distilled water, and close the valve after rinsing;

[0080] Step 6: Turn on the fan 23 of the drying assembly 2 and set the drying temperature through the heater 22 to dry the sample;

[0081] Step 7: After the sample is dried, turn on the contact angle measuring instrument 9, open the push-pull plate 25 and the partition plate 26 so that the sample is photographed by the high-speed camera;

[0082] Step 8: Move the buckle 18 of the sample to be measured within the range of the high-speed camera, move the remaining buckles 18 outside the range, use the control system to control the servo motor 53 to drive the burette 56 to move directly above the sample, ensure that the liquid outlet of the titration needle is within the range of the high-speed camera shooting of the sample surface, and drive the titration assembly 5 to move in the vertical direction under the movement of the stepping motor 19;

[0083] Step 9: Adjust the titrant in the burette 56 to form a liquid drop about to drip at the titration needle, move the burette 56 downward until the liquid drop falls onto the sample surface and then leaves, presenting a certain angle on the sample surface;

[0084] Step 10: Use the contact angle measuring instrument 9 to photograph the whole process of the titrant contacting the sample surface, form hundreds of photographed images, select clear and stable images from them, and use software to measure and calculate the contact angle;

[0085] Step 11: Repeat the above steps to measure the contact angle of the next group of sample surfaces;

[0086] Step 12: Measure and record the contact angle of the sample surface after modification with the modification liquid, and sort out, analyze and summarize the measured contact angle data.

[0087] For the measurement and calculation of the contact angle, the Young-Laplace equation is used for liquid drop shape analysis. The calculation formula for the contact angle θ is:

[0088]

[0089] Among them, γsv is the solid-gas interfacial tension, γs is the solid-liquid interfacial tension, and γlv is the liquid-gas interfacial tension, which are used to describe the contact angle of the liquid droplet on the solid surface and reflect the tension balance relationship of the solid-liquid-gas three-phase interface.

[0090] The type, concentration, volume, and immersion time of the modification liquid are set according to the experimental requirements. The relationship between the concentration C of the modification liquid and the contact angle θ can be fitted by the following empirical formula:

[0091] θ = a*C + b

[0092] Among them, a and b are fitting parameters, C is the concentration of the modification liquid. Through linear fitting, the influence law of the modification liquid concentration on the contact angle can be obtained.

[0093] The relationship between the drying temperature T and the drying time t is optimized by the following formula:

[0094]

[0095] Among them, k is the drying rate constant, and T0 is the ambient temperature. The drying temperature and time can be optimized to ensure that the sample is not affected by the external environment during the drying process.

[0096] The contact angle measuring instrument 9 captures the contact process of the liquid droplet on the sample surface through a high-speed camera. The contact angle θ of the liquid droplet is calculated by the following geometric formula:

[0097]

[0098] Among them, h is the height of the liquid droplet, and r is the radius of the bottom of the liquid droplet. The contact angle can be directly calculated through the height and bottom radius of the liquid droplet, which is applicable to the case where the shape of the liquid droplet is relatively regular.

[0099] By adopting the above technical solutions:

[0100] When performing integrated contact angle measurement of sample modification, drying, and determination, it can not only measure the influence of different modification conditions on the contact angle, but also avoid the influence of environmental temperature and humidity changes on the sample during the step-by-step operation, significantly shortening the measurement period of the contact angle, improving the measurement efficiency, and reducing material loss.

[0101] Working principle:

[0102] Fix the measured sample on the buckle 18 of the tray 6. Rotate and move the drying component 2 through the rotating ring 3 so that the drying component 2 faces the card slot 16 of the tray 6. Then, the lifting cylinder 20 moves to drive the tray 6 to move upward and align and connect with the drying component 2. After that, set the temperature of the drying component 2, open the valve of the connecting pipe 8 at the bottom of the modification liquid container 13, connect the modification liquid container 13 with the drying component 2, and soak the sample with the modification liquid. Close the valve after reaching the set soaking volume. After the sample reaches the modification time, open the switch of the drain pipe 11 to make the modification liquid flow into the waste liquid bucket 10. Close the valve of the modification liquid container 13, open the valve of the connecting pipe 8 at the bottom of the distilled water container 12, connect the distilled water container 12 with the drying component 2, and rinse the test sample with distilled water. After rinsing, close the valve, turn on the fan 23 of the drying component 2 and set the drying temperature through the heater 22 to dry the sample. After the sample is dried, turn on the contact angle measuring instrument 9. At this time, open the push-pull plate 25 and the partition plate 26 so that the sample is photographed by the high-speed camera. Use the control system to control the servo motor 53 to drive the burette 56 to move above the sample, ensuring that the liquid outlet of the burette needle is within the range photographed by the high-speed camera. Then, drive the burette 56 to move vertically through the stepping motor 19 to adjust the titrant in the burette 56 to form a liquid drop about to drip at the burette needle. The burette 56 moves downward until the liquid drop falls on the sample surface and leaves, presenting a certain angle on the sample surface. Use the contact angle measuring instrument 9 to photograph the whole process of the titrant contacting the sample surface, forming hundreds of photographed images. Select clear and stable images from them, and use software to measure and calculate the contact angle. Repeat the above steps to measure the contact angle on the surface of the next group of samples, measure and record the contact angle on the surface of the sample after modification with the modification liquid, and sort out, analyze and summarize the measured contact angle data.

[0103] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A solid contact angle measuring device considering surface modification, characterized in that: include: A tray (6), a drying component (2) is arranged above the tray (6), a lifting cylinder (20) is arranged at the bottom of the tray (6), a card slot (16) corresponding to the drying component (2) is arranged at the center of the tray (6), the card slot (16) is evenly divided into three rectangular parts, each rectangular part is connected to a buckle (18), the buckle (18) can slide inside the card slot (16) for fixing the sample to be tested, and a leak hole (17) is penetrated at one end of the buckle (18) for connecting with a pipeline; A drying component (2), the drying component (2) comprising a drying box (21) connected to the tray (6), two rows of fans (23) being embedded in the top of the drying box (21), heaters (22) being connected to both sides of the drying box (21), the bottom of the drying box (21) being not closed, a partition (26) being provided inside, and a groove (24) being provided on the inner side of the two rows of fans (23) at the top of the drying box (21); A titration assembly (5), the titration assembly (5) comprising a support rod (54), a slide groove (52) being provided inside the support rod (54), a slider (55) being slidably connected inside the slide groove (52), a burette (56) being connected at the bottom end of the slider (55), and a stroke assembly being connected through the slider (55); And, a contact angle measuring instrument (9), wherein one end of the contact angle measuring instrument (9) is connected to a bracket (7), wherein the bracket (7) is an L-shaped structure, and the bracket (7) is installed at one end of the tray (6) away from one end of the contact angle measuring instrument (9), and is used to measure a sample fixed above the tray (6).

2. A solid contact angle measuring device considering surface modification as claimed in claim 1, characterized in that: A support frame (1) is provided at one end of the tray (6) away from the bracket (7); the support frame (1) is located above the tray (6) and is connected to a rotating ring (3) connected to the drying component (2); the rotating ring (3) is fixedly connected to the drying component (2); the rotating ring (3) is rotatable around the support frame (1) and is used to drive the drying component (2) to rotate; a fixed ring (28) is provided at the bottom end of the rotating ring (3) and is used to be connected to the lifting cylinder (20); and the bottom end of the support frame (1) is connected to a bottom plate (4); Wherein, the bottom end of the tray (6) is connected to a drainage pipe (11) at a position corresponding to the leakage hole (17), and the bottom end of the drainage pipe (11) is connected to a waste liquid bucket (10).

3. A solid contact angle measuring device considering surface modification as claimed in claim 2, characterized in that: The stroke assembly comprises a servo motor (53) connected to the support rod (54); the output end of the servo motor (53) is connected to a screw rod (57); the screw rod (57) is screw-connected to the slider (55); and the other end of the screw rod (57) is provided with a baffle (58); A collar (51) is provided at the connection between the support rod (54) and the support frame (1), a stepping motor (19) is provided at the top of the support frame (1), and a limiting groove (14) is provided at the intersection of the support frame (1) and the titration component (5). When the stepping motor (19) is running, the titration component (5) is driven to move up and down inside the limiting groove (14).

4. A solid contact angle measuring device considering surface modification as claimed in claim 3, characterized in that: The cross bar (15) is located at one end of the support frame (1) and is provided with a distilled water container (12) and three modified liquid containers (13); The bottom ends of the distilled water container (12) and the modified liquid container (13) are both connected to a connecting pipe (8), and a valve is provided inside the connecting pipe (8) for controlling the flow of the solution inside the distilled water container (12) and the modified liquid container (13).

5. A solid contact angle measuring device considering surface modification as claimed in claim 1, characterized in that: The drying box (21) is provided with a push-pull plate (25) at one end of the contact angle measuring instrument (9), and a through hole (27) is penetrated through the bottom end of the heater (22) inside the drying box (21).

6. A method for measuring the contact angle of a solid taking into account surface modification, characterized in that: The following steps are involved: Step 1: Fix the sample to be measured on the buckle (18) of the tray (6); Step 2: Rotate and move the drying component (2) so that the drying component (2) faces the slot (16) of the tray (6) and is aligned and connected thereto, and then set the temperature of the drying component (2); Step 3: Open the valve of the connecting pipe (8) at the bottom of the modifying liquid container (13), connect the modifying liquid container (13) to the drying assembly (2), allow the modifying liquid to soak the sample, and close the valve after reaching the set soaking volume; Step 4: After the sample reaches the modification time, open the switch of the drain pipe (11) to allow the modified liquid to flow into the waste liquid bucket (10); Step 5: Close the valve of the modified liquid container (13), open the valve of the connecting pipe (8) at the bottom of the distilled water container (12), connect the distilled water container (12) to the drying assembly (2), and rinse the test sample with distilled water. After the rinsing is completed, close the valve; Step 6: Turn on the fan (23) of the drying component (2) and set the drying temperature through the heater (22) to dry the sample; Step 7: After the sample is dried, the contact angle measuring instrument (9) is turned on, and the push-pull plate (25) and the partition (26) are opened, so that the sample can be photographed by a high-speed camera; Step 8: Move the buckle (18) of the sample to be tested into the range of the high-speed camera, and move the other buckles (18) out of the range, and use the control system to control the servo motor (53) to drive the burette (56) to move directly above the sample, ensuring that the liquid outlet of the titration needle and the sample surface are within the range of the high-speed camera, and drive the titration assembly (5) to move in the vertical direction under the movement of the stepper motor (19); Step 9: Adjust the titrant in the burette (56) to form a droplet at the titration needle that is about to drip, and move the burette (56) downward until the droplet falls on the sample surface and leaves, presenting a certain angle on the sample surface; Step 10: Using a contact angle measuring instrument (9) to photograph the entire process of the titration solution contacting the sample surface, forming hundreds of photographed images, from which clear and stable images are selected, and the contact angle is measured and calculated using software; Step 11: Repeat the above steps to measure the contact angle of the next set of samples; Step 12: Measure and record the surface contact angle of the sample after being treated with the modification liquid, and organize, analyze and summarize the measured contact angle data.

7. A method for measuring the contact angle of a solid taking into account surface modification according to claim 6, characterized in that: The measurement and calculation of the contact angle adopts the Young-Laplace equation to analyze the drop shape, and the calculation formula of the contact angle θ is: Among them, γsv is the solid-gas interfacial tension, γs is the solid-liquid interfacial tension, and γlv is the liquid-gas interfacial tension, which is used to describe the contact angle of the droplet on the solid surface and reflects the tension balance relationship of the solid-liquid-gas three-phase interface.

8. A method for measuring contact angle of a solid taking into account surface modification according to claim 6, characterized in that: The type, concentration, volume and immersion time of the modifying liquid are set according to the experimental requirements. The relationship between the concentration C of the modifying liquid and the contact angle θ can be fitted by the following empirical formula: θ=a*C+b Among them, a and b are fitting parameters, C is the concentration of the modifying liquid, and through linear fitting, the influence of the concentration of the modifying liquid on the contact angle can be obtained.

9. A method for measuring contact angle of a solid taking into account surface modification according to claim 6, characterized in that: The relationship between the drying temperature T and the drying time t is optimized by the following formula: Among them, k is the drying rate constant and T0 is the ambient temperature. The drying temperature and time can be optimized to ensure that the sample is not affected by the external environment during the drying process.

10. A method for measuring the contact angle of a solid taking into account surface modification according to claim 6, characterized in that: The contact angle measuring instrument (9) uses a high-speed camera to shoot the contact process of the droplet on the sample surface, and the contact angle θ of the droplet is calculated using the following geometric formula: Among them, h is the height of the droplet, r is the radius of the bottom of the droplet. The contact angle can be directly calculated through the height and bottom radius of the droplet, which is suitable for situations where the droplet shape is relatively regular.

Images