CN110132798B - Device and method for measuring advancing/retreating angle of solid-liquid interface under electric field - Google Patents
Device and method for measuring advancing/retreating angle of solid-liquid interface under electric field Download PDFInfo
- Publication number
- CN110132798B CN110132798B CN201910501030.3A CN201910501030A CN110132798B CN 110132798 B CN110132798 B CN 110132798B CN 201910501030 A CN201910501030 A CN 201910501030A CN 110132798 B CN110132798 B CN 110132798B
- Authority
- CN
- China
- Prior art keywords
- polar plate
- plate
- advancing
- electric field
- conductive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 106
- 238000000034 method Methods 0.000 title claims abstract description 61
- 230000005684 electric field Effects 0.000 title claims abstract description 40
- 230000008569 process Effects 0.000 claims abstract description 20
- 238000003825 pressing Methods 0.000 claims abstract description 15
- 238000007906 compression Methods 0.000 claims abstract description 11
- 238000002474 experimental method Methods 0.000 claims abstract description 11
- 238000012545 processing Methods 0.000 claims abstract description 11
- 230000009471 action Effects 0.000 claims abstract description 7
- 230000006835 compression Effects 0.000 claims abstract description 7
- 238000006073 displacement reaction Methods 0.000 claims description 31
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 26
- 229910052802 copper Inorganic materials 0.000 claims description 26
- 239000010949 copper Substances 0.000 claims description 26
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 17
- 229910052710 silicon Inorganic materials 0.000 claims description 17
- 239000010703 silicon Substances 0.000 claims description 17
- 230000002209 hydrophobic effect Effects 0.000 claims description 15
- 238000004528 spin coating Methods 0.000 claims description 12
- 238000000576 coating method Methods 0.000 claims description 9
- 239000004033 plastic Substances 0.000 claims description 9
- 229910001220 stainless steel Inorganic materials 0.000 claims description 9
- 239000010935 stainless steel Substances 0.000 claims description 9
- 239000004809 Teflon Substances 0.000 claims description 8
- 229920006362 Teflon® Polymers 0.000 claims description 8
- 239000011248 coating agent Substances 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 8
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 7
- 230000002745 absorbent Effects 0.000 claims description 6
- 239000002250 absorbent Substances 0.000 claims description 6
- 239000002994 raw material Substances 0.000 claims description 6
- 238000005520 cutting process Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- 239000004020 conductor Substances 0.000 claims description 4
- 238000004140 cleaning Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 239000000839 emulsion Substances 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 238000004506 ultrasonic cleaning Methods 0.000 claims description 3
- 238000005259 measurement Methods 0.000 abstract description 7
- 230000004660 morphological change Effects 0.000 abstract description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 230000008859 change Effects 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 229910052681 coesite Inorganic materials 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 229910052906 cristobalite Inorganic materials 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000012827 research and development Methods 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 229910052682 stishovite Inorganic materials 0.000 description 2
- 229910052905 tridymite Inorganic materials 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 241001391944 Commicarpus scandens Species 0.000 description 1
- 230000003373 anti-fouling effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Length Measuring Devices By Optical Means (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The invention discloses a device and a method for measuring the advancing/retreating angle of a solid-liquid interface under an electric field, wherein liquid drops to be measured are placed between two charged polar plates, the liquid drops are respectively contacted with the two charged polar plates, the two charged polar plates generate compression or stretching action on the liquid drops to be measured in the process of folding or separating movement, so that the contact line of the liquid drops to be measured moves forwards or backwards on the polar plates, the morphological change of the liquid drops when the liquid drops are compressed or stretched is recorded by a high-speed camera, and the advancing/retreating angle of the liquid drops to be measured under the electric field is obtained through image processing. The method can adjust parameters such as upper and lower polar plates, a pulling and pressing device, droplet types, electric field sizes and the like according to specific conditions of experiments, can further improve the accuracy and compatibility of the experiments, realizes the measurement of advancing/retreating angles of various droplets in different environments by one experimental device, and can well meet the requirements of measuring the advancing/retreating angles of solid-liquid interface droplets in the electric field.
Description
Technical Field
The invention relates to a device and a method for measuring the advancing/retreating angle of a solid-liquid interface under an electric field, which can be used for precisely measuring the advancing/retreating angle of different materials and different liquid drops under the electric field, and belongs to the technical field of measurement.
Background
The wetting characteristic of the solid-liquid interface plays an important role in aspects of medicine development, vehicle antifouling, material protection, glass self-cleaning and the like. The advancing/receding angle of the liquid drop on the solid surface is the macroscopic expression of the interaction relation of the solid/liquid/gas interface, and is one of the most important parameters for researching the solid-liquid interface behavior. The method for controlling the movement of the micro liquid drops through the electric field has wide application in industries such as micro fluid chips, electrowetting lenses, electronic paper and the like, and the measurement of the advancing/retreating angle of the solid-liquid interface under the electric field is a key step in the research and development of products, so that the research and development of a method capable of rapidly and accurately measuring the advancing/retreating angle of the solid-liquid interface under the electric field is needed.
There are two methods for measuring the advancing/retreating angle of a droplet, one is an adding/subtracting method and the other is an inclined plate method. The liquid adding/subtracting method is to drop standard test liquid onto the surface of the solid to be measured at preset flow rate through the micropump of the contact angle measuring instrument, record the change condition of the contact line and contact angle of the solid-liquid interface in the liquid adding/subtracting process through the high-speed camera, and obtain the advancing/retreating angle of the liquid drop through the analysis of image software. The liquid drops used in the method are several types of fixed liquid to be tested, and complicated debugging is needed to be carried out if the advancing/retreating angle of the special liquid drops is to be measured, so that the experimental efficiency is greatly influenced. The inclined plate method is to place the drop to be measured on the surface of the sample to be measured, incline the surface of the sample to be measured slowly and uniformly, change the form of the drop under the action of gravity and roll the drop, collect the form of the drop sliding moment through the image, thus obtain the advancing/retreating angle of the drop. The method uses the gravity of the liquid drop as a power source, has strict requirements on the volume of the liquid drop and the inclination angle of the surface to be measured, is inconvenient to operate and has a small practical range. The above method is suitable for measuring the advancing/receding angle of a droplet in the absence of an electric field. However, the electric field is required to be introduced to measure the advancing/retreating angle of the liquid drop between the solid-liquid interfaces under the electric field, and the introduction of the electric field may reduce the testing accuracy of the instrument or cause damage to the instrument. Therefore, the above measurement method cannot complete the forward/backward angle test under the electric field condition, and therefore, development of a method which is convenient to operate, high in measurement accuracy, and suitable for the electric field environment, and can accurately and rapidly measure the forward/backward angle of the liquid drop between the solid-liquid interfaces is needed.
Disclosure of Invention
It is an object of the present invention to address at least the above problems and/or disadvantages and to provide at least the advantages described below.
To achieve these objects and other advantages and in accordance with the purpose of the invention, there is provided an apparatus for measuring a solid-liquid interface advancing/retreating angle in an electric field, comprising:
a plastic transparent operation box;
a horizontal bottom plate arranged in the plastic transparent operation box;
The electric displacement platform is connected above the horizontal bottom plate through a support frame; the telescopic platform of the electric displacement platform faces the horizontal bottom plate;
a copper plate connected to the horizontal base plate;
a lower plate bonded to the copper plate through conductive gel;
One end of the conductive pulling and pressing rod is connected to the telescopic platform of the electric displacement platform, the other end of the conductive pulling and pressing rod is bonded to the upper polar plate through conductive gel, so that the upper polar plate is positioned above the lower polar plate, and the upper polar plate and the lower polar plate form a liquid drop accommodating space;
The power supply is arranged on the horizontal bottom plate, the positive electrode of the power supply is connected with the stainless steel tension-compression bar, and the negative electrode of the power supply is connected with the copper plate;
The high-speed camera is arranged on the horizontal bottom plate, and a camera of the high-speed camera is aligned with a liquid drop accommodating space formed by the upper polar plate and the lower polar plate.
Preferably, the lower plate includes: the silicon wafer, an insulating layer plated on the silicon wafer and a hydrophobic layer coated on the insulating layer.
Preferably, the insulating layer is a SiO2 coating with a thickness of 200-400 nm, and the hydrophobic layer is a Teflon layer.
Preferably, the upper plate includes: a silicon wafer and a hydrophobic layer coated on the insulating layer.
Preferably, the conductive pulling compression bar is a stainless steel pulling compression bar.
The invention also provides a method for measuring the advancing/retreating angle of the solid-liquid interface under the electric field by adopting the device, which comprises the following steps:
Firstly, cutting the surface of a solid to be detected to obtain a polar plate raw material, cleaning and drying the polar plate raw material, and preparing a lower polar plate and an upper polar plate by adopting the polar plate raw material;
step two, adopting a conductive material to manufacture a conductive pulling and pressing rod, and using conductive gel to bond one end of the conductive pulling and pressing rod on a telescopic platform of the electric displacement platform;
Bonding an upper polar plate to the other end of the conductive tension rod through conductive gel, bonding a lower polar plate to a copper plate through conductive gel, mounting the copper plate on a horizontal bottom plate, enabling the upper polar plate, the tension rod, the lower polar plate and the copper plate to be in a conducting state respectively, connecting a positive electrode of a power supply with the conductive tension rod, and connecting a negative electrode of the power supply with the copper plate;
step four, dripping liquid drops to be detected on the lower polar plate on the surface of the copper plate, adjusting the electric displacement platform to enable the upper polar plate at the tail end of the conductive tension rod to be positioned at a position about 5mm above the liquid drops, and starting a power supply to set a voltage value;
Step five, starting a high-speed camera to record an experiment process, starting an electric displacement platform to enable the electric displacement platform to move at a set speed, enabling an upper polar plate and a lower polar plate to be in contact with the liquid drop to be detected and completing folding and separating actions, so that the liquid drop to be detected can complete compression and stretching movements, and enabling a contact line of the liquid drop to be detected to move forwards and backwards;
And step six, after processing the image data acquired by the high-speed camera, measuring the advancing angle and the retreating angle of the liquid drop when the liquid drop is compressed and stretched.
Preferably, the specific process of the first step is as follows: cutting a silicon wafer with a 200-400 nm SiO2 coating on the surface into a 15mm multiplied by 15mm standard sample, then carrying out ultrasonic cleaning on the standard sample for 5min, absorbing the moisture on the surface by using absorbent paper, drying the absorbent paper, and keeping the surface clean; placing the cleaned standard sample in a desk type spin coater, and spin-coating a Teflon emulsion; the spin coating parameters of the table type spin coater are as follows: spin-coating for 20s at a low speed of 500 r/min; spin-coating for 30s at a high speed of 3000 r/min; finally, placing the spin-coated experimental sample in a baking oven at 200 ℃ for baking for 2 hours, and naturally cooling to obtain a lower polar plate;
Spraying a hydrophobic liquid on the surface of a pure silicon wafer sample, and naturally drying to obtain an upper polar plate;
The surface hydrophobicity of the upper polar plate is smaller than that of the lower polar plate, namely the surface contact angle of the upper polar plate is smaller than that of the lower polar plate.
Preferably, the preparation method of the conductive tension rod comprises the following steps: and (3) taking a stainless steel tube with the length of 80-150 mm, the outer diameter of 0.5mm and the inner diameter of 0.25mm to prepare the conductive tension-compression bar.
Preferably, in the fourth step, the voltage value is 0 to 200V; in the fifth step, the moving speed of the electric displacement platform is 0.01-0.02 mm/s.
The invention at least comprises the following beneficial effects:
(1) The invention has strong operability and low manufacturing cost, and operators can flexibly adjust according to actual conditions.
(2) The invention can realize the measurement of various liquids without adjusting an experimental scheme, can measure under an electric field and other atmospheres, avoids the tedious work of replacing test liquid by an adding/subtracting liquid method, and has no special requirements on the volume and the property of liquid drops.
(3) The experimental process can be carried out at normal temperature and normal pressure, and special experimental environments such as dust-free, constant temperature, constant humidity and the like are not needed; meanwhile, the detection time is short, a group of experiments can be completed within 4-5 minutes, and the experimental efficiency can be greatly improved.
(4) The measuring method is suitable for measuring the advancing/retreating angles of various surfaces and liquid under an electric field, has the characteristics of convenience in use, wide application range and high measuring precision, and can well meet the requirements of measuring the advancing/retreating angles of a solid-liquid interface under the electric field.
(5) The method is suitable for measuring the liquid advancing/retreating angle under the electric field, the liquid is easy to generate asymmetric deformation by using the traditional measuring method under the electric field, and once the asymmetric deformation occurs, the fitting curve function can generate great inaccuracy, so that larger errors can occur in the measured angles of the left side and the right side of the liquid. However, the invention can effectively prevent the generation of asymmetric deformation of liquid drops under an electric field by the restraining action of the upper and lower bipolar plates, thereby improving the measurement precision and accuracy.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Description of the drawings:
FIG. 1 is a schematic structural view of an apparatus for measuring the advancing/retreating angle of a solid-liquid interface under an electric field according to the present invention.
The specific embodiment is as follows:
The present invention is described in further detail below with reference to the drawings to enable those skilled in the art to practice the invention by referring to the description.
It will be understood that terms, such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.
Fig. 1 shows an apparatus for measuring a solid-liquid interface advancing/retreating angle under an electric field according to the present invention, comprising:
a plastic transparent operation box 1;
A horizontal bottom plate 2 disposed in the plastic transparent operation box 1;
An electric displacement platform 7 connected above the horizontal bottom plate 2 through a support frame 3; and the telescopic platform of the electric displacement platform 7 faces the horizontal bottom plate 2;
a copper plate 11 connected to the horizontal base plate 2;
A lower plate 8 bonded to the copper plate 11 by conductive gel;
One end of a conductive pulling and pressing rod 12 is connected to the telescopic platform of the electric displacement platform 7, and the other end of the conductive pulling and pressing rod is bonded to the upper polar plate 10 through conductive gel, so that the upper polar plate 10 is positioned above the lower polar plate 8, and the upper polar plate 10 and the lower polar plate 8 form a liquid drop accommodating space;
The power supply 5 is arranged on the horizontal bottom plate 2, the positive electrode of the power supply is connected with the stainless steel tension rod through a lead I4, and the negative electrode of the power supply is connected with the copper plate 11 through a lead II 6; the copper plate 11, the lower polar plate 8, the upper polar plate 10 and the conductive pulling and pressing rod 12 are sequentially connected in series in a circuit;
A high-speed camera 13 is arranged on the horizontal bottom plate 2, and a camera of the high-speed camera 13 is aligned with a liquid drop accommodating space formed by the upper polar plate 10 and the lower polar plate 8.
In the technical scheme, a drop to be detected is dripped on a lower polar plate on the surface of a copper plate, an electric displacement platform is regulated to enable an upper polar plate connected to a conductive tension rod to be positioned at a position about 5mm above the drop, and a power supply is started to set a voltage value; and starting the high-speed camera to record an experiment process, starting the electric displacement platform to enable the electric displacement platform to move at a set speed, enabling the upper polar plate and the lower polar plate to be in contact with the liquid drop to be detected and complete folding and separating actions, so that the liquid drop to be detected can complete compressing and stretching movements, enabling the contact line of the liquid drop to be detected to move forwards and backwards, and measuring the advancing angle and the retreating angle of the liquid drop when the liquid drop is compressed and stretched after image data acquired by the high-speed camera are processed.
In the above technical solution, the image data collected by the high-speed camera may be imported into an external data control processing terminal (such as a computer) and processed by using image processing software (in the present invention, a mode of manually fitting an image by using CAD software); the data control processing terminal 16 (such as a computer) can be arranged outside the plastic transparent operation box, the high-speed camera is connected with the data control processing terminal 16 in an electric communication way through the image data output port 15 arranged on the plastic transparent operation box, and the image data collected by the high-speed camera can be directly imported into the data control processing terminal for processing; meanwhile, the electric displacement platform 7 is connected with the data control processing terminal in an electric communication way through a displacement input port 14 arranged on the plastic transparent operation box, so that the control of the data control processing terminal on the electric displacement platform is realized; the method mainly sets up the mode of the integrated port to output data uniformly and synchronously, so that a certain section of data and video information can be conveniently extracted for analysis.
In the above technical solution, the lower plate includes: the silicon wafer, an insulating layer plated on the silicon wafer and a hydrophobic layer coated on the insulating layer. The silicon wafer is selected as the conducting layer because the silicon wafer is the most mature semiconductor conducting material at present, and compared with other materials, the cost performance is highest.
In the technical scheme, the insulating layer is a SiO 2 coating with the thickness of 200-400 nm, and the hydrophobic layer is a Teflon layer. The SiO 2 coating is selected because SiO 2 is the insulating material with the widest application range, the cost performance is the highest in consideration of the manufacturing technology and the cost, the coating of the hydrophobic layer is not influenced by the smoothness of the surface of SiO 2, and the thickness of 200-400 nm is selected because when the thickness is too small, the larger contact angle change can be obtained under the condition of smaller voltage, but the hydrophobic layer is easy to break down; when the thickness is too large, a larger voltage is required if a larger contact angle variation is desired; the selection interval of 200-400 nm is the best under the existing experimental conditions is obtained through consulting the related data and experiments. Teflon is used as the hydrophobic layer because Teflon has the advantages of excellent chemical stability, low price, corrosion resistance and the like, and compared with a metal vapor deposition method and a plasma chemical vapor deposition method, the coating method has the advantages of low experimental environment requirement, low cost and simple experimental operation.
In the above technical solution, the upper plate includes: a silicon wafer and a hydrophobic layer coated on the insulating layer.
In the technical scheme, the conductive tension rod is a stainless steel tension rod, and the stainless steel tension rod has excellent conductivity while guaranteeing the strength of the tension rod.
Example 1:
The method for measuring the advancing/retreating angle of the solid-liquid interface under the electric field by adopting the device comprises the following steps:
The specific process of the first step is as follows: cutting a silicon wafer with a 300nm SiO 2 coating on the surface into a 15mm multiplied by 15mm standard sample, then carrying out ultrasonic cleaning on the standard sample for 5min, absorbing the water on the surface by using absorbent paper, drying the absorbent paper, and keeping the surface clean; placing the cleaned standard sample in a desk type spin coater, and spin-coating a Teflon emulsion; the spin coating parameters of the table type spin coater are as follows: spin-coating for 20s at a low speed of 500 r/min; spin-coating for 30s at a high speed of 3000 r/min; finally, placing the spin-coated experimental sample in a baking oven at 200 ℃ for baking for 2 hours, and naturally cooling to obtain a lower polar plate;
Spraying a hydrophobic liquid on the surface of a pure silicon wafer sample, and naturally drying to obtain an upper polar plate;
The surface hydrophobicity of the upper polar plate is smaller than that of the lower polar plate, namely the surface contact angle of the upper polar plate is smaller than that of the lower polar plate; in this way, the drop can be completely separated from the lower polar plate in the rising process of the upper polar plate;
Step two, adopting a conductive material to manufacture a conductive pulling and pressing rod, and using conductive gel to bond one end of the conductive pulling and pressing rod on a telescopic platform of the electric displacement platform; the preparation method of the conductive tension rod comprises the following steps: taking a stainless steel tube with the length of 100mm, the outer diameter of 0.5mm and the inner diameter of 0.25mm to prepare a conductive tension-compression bar;
Bonding an upper polar plate to the other end of the conductive tension rod through conductive gel, bonding a lower polar plate to a copper plate through conductive gel, mounting the copper plate on a horizontal bottom plate, enabling the upper polar plate, the tension rod, the lower polar plate and the copper plate to be in a conducting state respectively, connecting a positive electrode of a power supply with the conductive tension rod, and connecting a negative electrode of the power supply with the copper plate;
step four, dripping liquid drops (deionized water) to be detected on the surface of the lower polar plate on the surface of the copper plate, adjusting the electric displacement platform to enable the upper polar plate at the tail end of the conductive tension rod to be positioned at the position about 5mm right above the liquid drops, and starting a power supply to set the voltage value to be 0V;
Step five, starting a high-speed camera to record an experiment process, starting an electric displacement platform to enable the electric displacement platform to descend at the speed of 0.015mm/s, observing the change of a contact line of a lower polar plate of the liquid drop in the experiment, and after the contact line of the lower polar plate of the liquid drop to be detected is obviously moved, moving the electric displacement platform upwards at the speed of 0.015mm/s until the liquid drop to be detected is completely separated from a sample of the lower polar plate, and stopping the movement of the electric displacement platform; (the process mainly enables the upper polar plate and the lower polar plate to be in contact with the liquid drop to be tested and complete folding and separating actions, so that the liquid drop to be tested is subjected to compression and stretching movements, and the contact line of the liquid drop to be tested is moved forwards and backwards), and the morphological change image of the liquid drop recorded by the high-speed camera in the whole experimental process is derived;
And step six, after image data acquired by the high-speed camera are processed by adopting image processing software, measuring the advancing angle and the retreating angle of the liquid drop when the liquid drop is compressed and stretched.
Example 2:
In the fourth step, the power supply is started to set the voltage value to be 50V; the remaining process parameters and procedures were exactly the same as in example 1.
Example 3:
In the fourth step, the power supply is started to set the voltage value to 75V; the remaining process parameters and procedures were exactly the same as in example 1.
Example 4:
In the fourth step, a power supply is started to set a voltage value to 100V; the remaining process parameters and procedures were exactly the same as in example 1.
Example 5:
in the fourth step, the power supply is started to set the voltage value to 125V; the remaining process parameters and procedures were exactly the same as in example 1.
Example 6:
In the fourth step, a power supply is started to set a voltage value to 150V; the remaining process parameters and procedures were exactly the same as in example 1.
Example 7:
in the fourth step, a power supply is started to set a voltage value to 200V; the remaining process parameters and procedures were exactly the same as in example 1.
Table 1 shows the results of the advancing angles obtained in examples 1 to 7; table 2 shows the results of the relief angle obtained in examples 1 to 7; wherein each example tested 3 groups;
TABLE 1
TABLE 2
The invention designs a method for measuring the advancing/retreating angle of liquid drops at a solid-liquid interface under an electric field. And placing the liquid drop to be measured between the two charged polar plates, wherein the liquid drop is respectively contacted with the two charged polar plates. The two charged polar plates can generate compression or stretching action on the liquid drop to be detected in the process of folding or separating movement, so that the contact line of the liquid drop to be detected moves forwards or backwards on the polar plates, the morphological change of the liquid drop when the liquid drop is compressed or stretched is recorded by a high-speed camera, and the advancing/retreating angle of the liquid drop to be detected under an electric field is obtained through image processing. The method can adjust parameters such as upper and lower polar plates, a pulling and pressing device, droplet types, electric field sizes and the like according to specific conditions of experiments, can further improve the accuracy and compatibility of the experiments, realizes the measurement of advancing/retreating angles of various droplets in different environments by one experimental device, and can well meet the requirements of measuring the advancing/retreating angles of solid-liquid interface droplets in the electric field.
Although embodiments of the present invention have been disclosed above, it is not limited to the details and embodiments shown and described, it is well suited to various fields of use for which the invention would be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the specific details and illustrations shown and described herein, without departing from the general concepts defined in the claims and their equivalents.
Claims (7)
1. A method for measuring the advancing and retreating angles of a solid-liquid interface in an electric field, which is characterized in that the adopted device comprises:
a plastic transparent operation box;
a horizontal bottom plate arranged in the plastic transparent operation box;
The electric displacement platform is connected above the horizontal bottom plate through a support frame; the telescopic platform of the electric displacement platform faces the horizontal bottom plate;
a copper plate connected to the horizontal base plate;
a lower plate bonded to the copper plate through conductive gel;
One end of the conductive pulling and pressing rod is connected to the telescopic platform of the electric displacement platform, the other end of the conductive pulling and pressing rod is bonded to the upper polar plate through conductive gel, so that the upper polar plate is positioned above the lower polar plate, and the upper polar plate and the lower polar plate form a liquid drop accommodating space;
The power supply is arranged on the horizontal bottom plate, the anode of the power supply is connected with the conductive tension rod, and the cathode of the power supply is connected with the copper plate;
the high-speed camera is arranged on the horizontal bottom plate, and a camera of the high-speed camera is aligned with a liquid drop accommodating space formed by the upper polar plate and the lower polar plate;
the method for measuring the advancing and retreating angles of the solid-liquid interface under the electric field comprises the following steps:
Firstly, cutting the surface of a solid to be detected to obtain a polar plate raw material, cleaning and drying the polar plate raw material, and preparing a lower polar plate and an upper polar plate by adopting the polar plate raw material;
step two, adopting a conductive material to manufacture a conductive pulling and pressing rod, and using conductive gel to bond one end of the conductive pulling and pressing rod on a telescopic platform of the electric displacement platform;
Bonding an upper polar plate to the other end of the conductive tension rod through conductive gel, bonding a lower polar plate to a copper plate through conductive gel, mounting the copper plate on a horizontal bottom plate, enabling the upper polar plate, the tension rod, the lower polar plate and the copper plate to be in a conducting state respectively, connecting a positive electrode of a power supply with the conductive tension rod, and connecting a negative electrode of the power supply with the copper plate;
Step four, dripping liquid drops to be detected on a lower polar plate on the surface of the copper plate, adjusting an electric displacement platform to enable an upper polar plate at the tail end of the conductive tension rod to be positioned at a position 5mm above the liquid drops, and starting a power supply to set a voltage value;
Step five, starting a high-speed camera to record an experiment process, starting an electric displacement platform to enable the electric displacement platform to move at a set speed, enabling an upper polar plate and a lower polar plate to be in contact with the liquid drop to be detected and completing folding and separating actions, so that the liquid drop to be detected can complete compression and stretching movements, and enabling a contact line of the liquid drop to be detected to move forwards and backwards;
step six, after processing the image data collected by the high-speed camera, measuring the advancing angle and the retreating angle of the liquid drop when the liquid drop is compressed and stretched;
The specific process of the first step is as follows: cutting a silicon wafer with a SiO 2 coating with the surface of 200-400 nm into a standard sample with the thickness of 15mm multiplied by 15mm, then carrying out ultrasonic cleaning on the standard sample for 5min, absorbing the moisture on the surface by using absorbent paper, drying the absorbent paper, and keeping the surface clean; placing the cleaned standard sample in a desk type spin coater, and spin-coating a Teflon emulsion; the spin coating parameters of the table type spin coater are as follows: spin-coating for 20s at a low speed of 500 r/min; spin-coating for 30s at a high speed of 3000 r/min; finally, placing the spin-coated experimental sample in a baking oven at 200 ℃ for baking for 2 hours, and naturally cooling to obtain a lower polar plate;
Spraying a hydrophobic liquid on the surface of a pure silicon wafer sample, and naturally drying to obtain an upper polar plate;
The surface hydrophobicity of the upper polar plate is smaller than that of the lower polar plate, namely the surface contact angle of the upper polar plate is smaller than that of the lower polar plate.
2. The method of measuring the advancing and receding angle of a solid-liquid interface in an electric field according to claim 1, wherein the lower plate comprises: the silicon wafer, an insulating layer plated on the silicon wafer and a hydrophobic layer coated on the insulating layer.
3. The method for measuring the advancing and retreating angles of a solid-liquid interface in an electric field according to claim 2, wherein the insulating layer is a SiO 2 coating with a thickness of 200-400 nm, and the hydrophobic layer is a Teflon layer.
4. The method of measuring the advancing and retreating angles of a solid-liquid interface in an electric field according to claim 1, wherein the upper plate comprises: a silicon wafer and a hydrophobic layer coated on the insulating layer.
5. The method of measuring the advancing and retreating angles of a solid-liquid interface in an electric field according to claim 1, wherein the conductive tensile bar is a stainless steel tensile bar.
6. The method for measuring the advancing and retreating angles of a solid-liquid interface in an electric field according to claim 1, wherein the preparation method of the conductive tension rod is as follows: and (3) taking a stainless steel tube with the length of 80-150 mm, the outer diameter of 0.5mm and the inner diameter of 0.25mm to prepare the conductive tension-compression bar.
7. The method for measuring the advancing and retreating angles of a solid-liquid interface in an electric field according to claim 1, wherein in the fourth step, the voltage value is 0-200 v; in the fifth step, the moving speed of the electric displacement platform is 0.01-0.02 mm/s.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910501030.3A CN110132798B (en) | 2019-06-11 | 2019-06-11 | Device and method for measuring advancing/retreating angle of solid-liquid interface under electric field |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910501030.3A CN110132798B (en) | 2019-06-11 | 2019-06-11 | Device and method for measuring advancing/retreating angle of solid-liquid interface under electric field |
Publications (2)
Publication Number | Publication Date |
---|---|
CN110132798A CN110132798A (en) | 2019-08-16 |
CN110132798B true CN110132798B (en) | 2024-05-17 |
Family
ID=67581107
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201910501030.3A Active CN110132798B (en) | 2019-06-11 | 2019-06-11 | Device and method for measuring advancing/retreating angle of solid-liquid interface under electric field |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110132798B (en) |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3756196A (en) * | 1968-08-22 | 1973-09-04 | Asahi Glass Co Ltd | Method of coating glass surfaces |
JP2001116675A (en) * | 1999-10-22 | 2001-04-27 | Seiko Epson Corp | Contact angle measuring device, dynamic surface tension measuring device, contact angle measuring method and dynamic surface tension measuring method |
JP2003270117A (en) * | 2002-03-12 | 2003-09-25 | Seiko Epson Corp | Method and instrument for measuring dynamic contact angle |
CN105352856A (en) * | 2015-12-02 | 2016-02-24 | 宁波新边界科学仪器有限公司 | Method and device for measuring advancing contact angle, receding contact angle and retention force of liquid on solid surface |
CN108680468A (en) * | 2018-03-30 | 2018-10-19 | 西南科技大学 | A kind of method of solid liquid interface sliding critical voltage under measurement electric field |
CN109269978A (en) * | 2018-11-16 | 2019-01-25 | 西南科技大学 | Measure the measuring device and measuring method of adhesion strength between solid liquid interface under electric field |
CN109269976A (en) * | 2018-11-16 | 2019-01-25 | 西南科技大学 | Measure the measuring device and measuring method of frictional force between solid liquid interface under electric field |
CN109839331A (en) * | 2019-02-22 | 2019-06-04 | 江苏大学 | A kind of interfacial tension and contact angle integral type measuring device and method |
CN209992340U (en) * | 2019-06-11 | 2020-01-24 | 西南科技大学 | Device for measuring advancing/retreating angle of solid-liquid interface under electric field |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3210008B1 (en) * | 2014-10-24 | 2024-02-28 | Brighton Technologies LLC | Method and device for detecting substances on surfaces |
-
2019
- 2019-06-11 CN CN201910501030.3A patent/CN110132798B/en active Active
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3756196A (en) * | 1968-08-22 | 1973-09-04 | Asahi Glass Co Ltd | Method of coating glass surfaces |
JP2001116675A (en) * | 1999-10-22 | 2001-04-27 | Seiko Epson Corp | Contact angle measuring device, dynamic surface tension measuring device, contact angle measuring method and dynamic surface tension measuring method |
JP2003270117A (en) * | 2002-03-12 | 2003-09-25 | Seiko Epson Corp | Method and instrument for measuring dynamic contact angle |
CN105352856A (en) * | 2015-12-02 | 2016-02-24 | 宁波新边界科学仪器有限公司 | Method and device for measuring advancing contact angle, receding contact angle and retention force of liquid on solid surface |
CN108680468A (en) * | 2018-03-30 | 2018-10-19 | 西南科技大学 | A kind of method of solid liquid interface sliding critical voltage under measurement electric field |
CN109269978A (en) * | 2018-11-16 | 2019-01-25 | 西南科技大学 | Measure the measuring device and measuring method of adhesion strength between solid liquid interface under electric field |
CN109269976A (en) * | 2018-11-16 | 2019-01-25 | 西南科技大学 | Measure the measuring device and measuring method of frictional force between solid liquid interface under electric field |
CN109839331A (en) * | 2019-02-22 | 2019-06-04 | 江苏大学 | A kind of interfacial tension and contact angle integral type measuring device and method |
CN209992340U (en) * | 2019-06-11 | 2020-01-24 | 西南科技大学 | Device for measuring advancing/retreating angle of solid-liquid interface under electric field |
Non-Patent Citations (4)
Title |
---|
"Dynamic Contact Angles and Hysteresis under Electrowetting-on-Dielectric";Wyatt C. Nelson 等;《Langmuir》;20110713;第27卷(第16期);第10319–10326页 * |
"垂滴法测量CO2与不锈钢表面的接触角";裴念强 等;《科学通报》;20080115;第53卷(第1期);第122-125页 * |
"潮湿空气下浮法钠钙玻璃的摩擦磨损性能";肖童金 等;《硅酸盐学报》;20181212;第47卷(第2期);第270-278页 * |
Yafeng Zhang 等."Combined effects of pinning and adhesion force on solid\liquid interfacial friction behaviors under applied voltage".《Tribology International》.2019,第134卷第102-108页. * |
Also Published As
Publication number | Publication date |
---|---|
CN110132798A (en) | 2019-08-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN109269978B (en) | Measuring device and measuring method for measuring adhesion force between solid-liquid interfaces under electric field | |
CN109269976B (en) | Measuring device and measuring method for measuring friction force between solid-liquid interfaces in electric field | |
CN110044700B (en) | Transmission electron microscope in-situ liquid environment mechanical test platform | |
CN110057684B (en) | Thermoelectric electric coupling sample stage based on in-situ observation experiment | |
CN102183441B (en) | Method for measuring surface adhesive capacity and elastic modulus of soft material | |
CN104062322A (en) | Humidity sensor and preparation method thereof | |
WO2017114437A1 (en) | Method for enabling algae quantitatively and uniformly adhere to surface of silicone rubber test piece | |
CN110132798B (en) | Device and method for measuring advancing/retreating angle of solid-liquid interface under electric field | |
CN110579652A (en) | surface charge measuring method and device | |
CN209992340U (en) | Device for measuring advancing/retreating angle of solid-liquid interface under electric field | |
CN111077422A (en) | Lithium ion battery diaphragm breakdown strength testing device and testing method thereof | |
CN209432679U (en) | Measure the measuring device of adhesion strength between solid liquid interface under electric field | |
CN211627683U (en) | Automatic test system for contact resistance curve of bipolar plate of fuel cell | |
CN113340478A (en) | Preparation method of flexible stress sensor | |
CN110632105B (en) | Liquid sample cavity for transmission electron microscope characterization and preparation method thereof | |
Wu et al. | Printing of tactile sensors upon the surface of pneumatic soft gripper by direct writing and electrospraying to enable intelligent grasping | |
CN108152351B (en) | Micro-electrolysis cell for detecting formaldehyde and preparation method thereof | |
CN109342509A (en) | Contact resistance test machine and its method | |
CN217210832U (en) | Contact type nondestructive surface defect detection device | |
CN107314923B (en) | Gas enrichment device and liquid crystal bubble component analysis method | |
CN215768814U (en) | TCR testing device for chip semi-finished chip resistor | |
CN209432678U (en) | Measure the measuring device of frictional force between solid liquid interface under electric field | |
CN115436727A (en) | Thermoelectric device performance testing device | |
CN209416951U (en) | A kind of x-ray photoelectron spectroscopy powder sample quick preparation device | |
CN108654711B (en) | Method for reducing solid-liquid interface stick-slip behavior under electric field |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |