Solution dilution device based on ubbelohde viscometer test and working method

Abstract

The application relates to a solution dilution device and working method based on an Ubbelohde viscometer test, which comprises an inlet and outlet liquid unit, a tee joint, an interface A of the tee joint being connected with one end of a solution driving element through a pipeline, the other end of the solution driving element being connected with an inlet pipe of the Ubbelohde viscometer, an interface B being connected with a solvent bottle through a first control valve through a pipeline, an interface C being connected with a waste liquid bottle through a second control valve through a pipeline, a liquid quantitative unit, the solvent bottle and the waste liquid bottle being arranged on an electronic balance, weight data obtained by the electronic balance being sent to a control unit, the control unit being used for controlling the actions of the solution driving element, the first control valve and the second control valve, receiving the weight data obtained by the liquid quantitative unit and sending the weight data to an upper computer, and the upper computer outputting data of the solution after dilution according to an initial concentration of the solution in the Ubbelohde viscometer and the received weight data.

Description

Technical Field

[0001] This invention relates to the field of Ubbelohde viscometer technology, specifically to a solution dilution device and its working method based on Ubbelohde viscometer testing. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] An Ubbelohde viscometer is a capillary viscometer used to measure the time (outflow time) required for a specified volume of liquid to flow through a capillary tube of a specific diameter. Industrially, Ubbelohde viscometers are commonly used to determine the kinematic viscosity of petroleum products. In scientific research, they are primarily used to accurately determine the intrinsic viscosity of polymer materials. In polymer science, intrinsic viscosity is a crucial parameter characterizing the conformation of polymers in dilute solutions. The basic method for determining intrinsic viscosity is the "dilution method," which involves sequentially measuring the outflow time of the solution from high to low concentration using an Ubbelohde viscometer, and then obtaining the intrinsic viscosity of the polymer through conversion, plotting, and fitting.

[0004] In the actual implementation of the "dilution method," the initial concentration of the solution is usually determined based on research experience, which easily leads to situations where the prepared solution concentration is too high or too low. If the solution concentration is too low, the obtained data will have poor regularity due to the sensitivity limitations of the instrument. Therefore, in actual experiments, it is generally preferred to prepare an initial solution with a higher concentration. However, if the solution concentration is too high, the experiment deviates from the relevant assumptions of the "dilute solution theory," and the first few dilution points will no longer have a linear relationship. Theoretically, this situation can be resolved by continuing to dilute the solution in the Ubbelohde viscometer. However, the volume of the Ubbelohde viscometer's reservoir is limited; commonly used dilution-type Ubbelohde viscometers can be diluted to 6-7 times their minimum initial measurement volume (non-dilution-type can only be diluted to 2-3 times), making further dilution impossible.

[0005] In addition, traditional dilution methods require a relatively large amount of solvent for testing, and the traditional dilution method involves adding the solvent quantitatively to the viscometer using a graduated pipette, which has limited accuracy in measuring the volume of solvent. Summary of the Invention

[0006] To address the technical problems described in the background section, this invention provides a solution dilution device and operating method based on Ubbelohde viscometer testing. With the solution ready in the Ubbelohde viscometer, solvent can be quantitatively added to or extracted from the Ubbelohde viscometer. The quantitative method utilizes a precision electronic balance to calculate based on mass changes, resulting in high accuracy.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A first aspect of the present invention provides a solution dilution apparatus based on Ubbelohde viscometer testing, comprising:

[0009] The liquid inlet / outlet unit includes a three-way connector; interface A of the three-way connector is connected to one end of the solution drive unit via a pipe, and the other end of the solution drive unit is connected to the liquid inlet pipe of the Ubbelohde viscometer; interface B is connected to the solvent bottle via a pipe through a first control valve; and interface C is connected to the waste liquid bottle via a pipe through a second control valve.

[0010] The liquid dispensing unit includes a solvent bottle and a waste liquid bottle mounted on an electronic balance. The weight data acquired by the electronic balance is sent to the control unit.

[0011] The control unit is used to control the operation of the solution drive, the first control valve and the second control valve. It receives the weight data obtained by the liquid metering unit and sends it to the host computer. The host computer outputs the diluted solution data based on the initial concentration of the solution in the Ubbelohde viscometer and the received weight data.

[0012] One end of the first control valve is connected to port B of the tee fitting via a pipe, and the other end of the first control valve is connected to the solvent bottle via a pipe.

[0013] One end of the second control valve is connected to interface C of the tee fitting via a pipe, and the other end of the second control valve is connected to the waste liquid bottle via a pipe.

[0014] The tube connecting to the solvent bottle extends into the bottle, with the tube opening below the liquid level inside the bottle.

[0015] The pipe connecting the waste liquid bottle extends into the bottle, with the pipe opening positioned below the bottle opening and above the liquid level inside the bottle at a predetermined height.

[0016] The Ubbelohde viscometer includes an inlet tube, a vent tube, and a measuring tube. The bottom of the inlet tube is connected to the main reservoir bulb. The bottom of the vent tube and the measuring tube are connected to a buffer bulb and are also connected to the main reservoir bulb. The measuring tube has an upper reservoir bulb, a measuring bulb, and a capillary tube arranged sequentially from the opening to the bottom. There is an upper graduation line between the measuring bulb and the upper reservoir bulb, and a lower graduation line between the measuring bulb and the capillary tube.

[0017] The pipe connecting the Ubbelohde viscometer inlet extends into the main reservoir, with the inlet located below the liquid level inside the main reservoir.

[0018] The host computer outputs the amount of solvent pumped in or out by the solution drive based on the difference between the received initial weight and the final weight, and determines the data after dilution based on the initial concentration of the solution in the Ubbelohde viscometer.

[0019] A second aspect of the present invention provides a method for operating the above-described apparatus, comprising the following steps:

[0020] When injecting solvent into the Ubbelohde viscometer:

[0021] The control unit obtains initial mass data via an electronic balance;

[0022] The first control valve opens, the second control valve closes, the solution drive rotates forward for a set time, and the liquid is drawn from the solvent bottle into the Ubbelohde viscometer.

[0023] The first control valve is closed, the second control valve is opened, and the solution drive continues to rotate forward for the set time to empty the pipeline.

[0024] The first control valve opens, and after a set time, the control unit acquires the mass data at the end.

[0025] By using the initial and final mass data, as well as the initial concentration of the solution in the Ubbelohde viscometer, the weight of the pumped liquid, the volume of the solution in the Ubbelohde viscometer, and the concentration are obtained.

[0026] A third aspect of the present invention provides a method for operating the above-described apparatus, comprising the following steps:

[0027] When liquid is drawn from the Ubbelohde viscometer:

[0028] The control unit obtains initial mass data via an electronic balance;

[0029] The first control valve is closed, and the second control valve is opened; the solution drive reverses the set time to extract liquid from the Ubbelohde viscometer into the waste bottle;

[0030] The solution drive rotates forward for a set time to drain the residual solution from the pipeline;

[0031] The first control valve opens, and after a set time, the control unit acquires the mass data at the end.

[0032] By using the initial and final mass data, as well as the initial concentration of the solution in the Ubbelohde viscometer, the weight of the pumped liquid, the amount and concentration of the remaining liquid in the Ubbelohde viscometer are obtained.

[0033] Compared with existing technologies, one or more of the above technical solutions have the following beneficial effects:

[0034] 1. By connecting the control valve and solution drive unit to the port of the Ubbelohde viscometer for solution dilution through a three-way connector and pipeline, and in conjunction with the control unit and electronic balance, the solvent can be quantitatively injected into the Ubbelohde viscometer or quantitatively extracted from the Ubbelohde viscometer, thereby determining the amount and concentration of the solution in the Ubbelohde viscometer. The amount of solvent used for dilution is much smaller than that of traditional manual methods, and it has relatively higher accuracy.

[0035] 2. This device can achieve "infinite dilution." In actual testing, the initial solution concentration is always prepared slightly higher. However, if the concentration is too high, using traditional testing methods, only the last few data points can be used for linear fitting; the initial data points deviate from the assumptions of the "dilute solution theory" and do not show a linear relationship. Under traditional testing methods, this situation cannot be remedied due to the limited volume of the reservoir. This device, however, can achieve "infinite dilution" by quantitatively extracting the solution and adding solvent. Even if the initial concentration of the solution is high, it will not affect subsequent viscosity tests. Simply repeating the process multiple times will bring the solution into a reasonable concentration range, allowing the data points to show a linear relationship.

[0036] 3. Using an electronic balance, solvents can be weighed more accurately to a volume of 0.1 mg. 0.1 mg corresponds to a solution volume of 0.0001 mL, so the accuracy far exceeds that of traditional graduated pipettes, burettes and other glass instruments. Attached Figure Description

[0037] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0038] Figure 1 This is a schematic diagram of the structure of an automatic testing device for an Ubbelohde viscometer provided in one or more embodiments of the present invention;

[0039] Figure 2 This is a schematic diagram of the Ubbelohde viscometer structure provided in one or more embodiments of the present invention;

[0040] Figure 1 In the middle: 1. Liquid inlet / outlet unit, 11. First control valve, 12. Second control valve, 13. Peristaltic pump, 2. Liquid metering unit, 21. Solvent bottle, 22. Waste bottle, 3. Control unit, 4. Electronic balance, 5. Ubbelohde viscometer;

[0041] Figure 2 In the middle: 51. Inlet tube, 52. Vent tube, 53. Measuring tube, 54. Upper reservoir bulb, 55. Measuring bulb, 56. Buffer bulb, 57. Main reservoir bulb, 58. Capillary tube. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0043] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0044] As described in the background section, in the practical implementation of the "dilution method," it is common practice to prepare an initial solution with a relatively high concentration, which is then diluted in the Ubbelohde viscometer. However, the reservoir volume of the Ubbelohde viscometer is limited; typically, dilution-type Ubbelohde viscometers can only be diluted to 6-7 times their minimum initial measurement volume (non-dilution-type can only be diluted to 2-3 times), and further dilution is not possible. Clearly, the ideal method would be to quantitatively extract a portion of the liquid from the Ubbelohde viscometer before dilution, but traditional testing methods only quantify the liquid injected into the viscometer, making it difficult to quantify the extracted liquid using specialized instruments.

[0045] Traditional dilution methods require a relatively large amount of solvent. For example, if the solution in the Ubbelohde viscometer is 4 mg / mL and has a volume of 20 mL, diluting it by half to 2 mg / mL would require adding another 20 mL of solvent. Clearly, a more ideal dilution method is to extract a portion of the 20 mL, 4 mg / mL solution, such as 10 mL. This way, only 10 mL of solvent needs to be added to achieve the 2 mg / mL concentration. In actual experiments, traditional methods require 60–80 mL of solvent, while the latter method only requires about 30–40 mL. However, the latter method requires the ability to quantitatively extract liquid from the Ubbelohde viscometer during the test.

[0046] Traditional dilution methods involve quantitatively adding solvent to a viscometer using graduated pipettes. However, the accuracy of measuring solvent volume using graduated pipettes is limited. According to standard GB / T12807-2021, the smallest graduations for 5mL and 10mL graduated pipettes are 0.02mL and 0.05mL, respectively, which also limits the accuracy of solvent volume measurement. In contrast, if the solvent could be quantified by weighing, using a 0.1g electronic balance as an example, the measured solvent mass could be accurate to 0.1mg. Then, by converting the solvent's density, the volume could be accurate to 0.0001mL.

[0047] Therefore, the following embodiments provide a solution dilution device and operating method based on Ubbelohde viscometer testing. With the solution ready in the Ubbelohde viscometer, solvent can be quantitatively added to or extracted from the Ubbelohde viscometer. The quantitative method uses a precision electronic balance to calculate based on mass changes, resulting in high accuracy.

[0048] Example 1:

[0049] like Figures 1-2 As shown, the solution dilution device based on Ubbelohde viscometer testing includes:

[0050] The liquid inlet / outlet unit includes a three-way connector; interface A of the three-way connector is connected to one end of the solution drive unit through a pipe, and the other end of the solution drive unit is connected to the liquid inlet pipe of the Ubbelohde viscometer; interface B is connected to one end of the first control valve through a pipe, and the other end of the first control valve is connected to the solvent bottle through a pipe; interface C is connected to one end of the second control valve through a pipe, and the other end of the second control valve is connected to the waste liquid bottle through a pipe.

[0051] The liquid dispensing unit includes a solvent bottle and a waste liquid bottle mounted on an electronic balance. The weight data acquired by the electronic balance is sent to the control unit.

[0052] The control unit is used to control the operation of the solution drive, the first control valve and the second control valve, and to receive the weight data acquired by the liquid metering unit and send it to the host computer.

[0053] In this embodiment, the liquid metering unit 3 includes a solvent bottle 21 and a waste liquid bottle 22 placed on the electronic metering unit 4, for storing and receiving solvent and waste liquid from the inlet and outlet liquid units.

[0054] In this embodiment, the liquid inlet / outlet unit 1 includes a solution drive component, a second control valve 12, and two control valves. Both control valves in this embodiment are electromagnetic clamp valves. The solution drive component can be a peristaltic pump 23, which is connected to several connecting conduits via a three-way connector. Controlled by the control unit 3, the dilution operation of the solution inside the Ubbelohde viscometer is achieved through a combination of actions such as the forward and reverse rotation of the pump and the opening and closing of the control valves.

[0055] like Figure 1 As shown, in the liquid inlet / outlet unit 1 of this embodiment, one end of the peristaltic pump 23 is connected to interface A of the three-way connector. Two interfaces, B and C, branch off from the three-way connector and are connected to flexible tubing. After the two tubing are connected to the corresponding control valves, needles of appropriate length and diameter are attached to each, and these needles are inserted into the solvent bottle 21 and waste bottle 22 of the liquid metering unit 3, respectively. The needle in the solvent bottle 21 is inserted to the bottom, while the needle in the waste bottle 22 is inserted just past the bottle opening. However, it is important to ensure that the needles are positioned a certain height above the liquid surface in the waste bottle 22 to prevent the waste liquid from being drawn back into the viscometer during subsequent emptying operations due to the forward rotation of the solution drive. The solution bottle 21 and waste bottle 22 are placed together on the tray of the electronic balance 4. The weight data from the electronic balance 4 is transmitted to the control unit 3 via a data interface or manual input. The other end of the peristaltic pump 23 passes through the interface (interface D) of the inlet / outlet unit 1 and is connected to a rigid thin tube of appropriate length and diameter. The thin tube extends from the inlet tube 51 of the Ubbelohde viscometer into the main reservoir ball 57 and is submerged below the liquid surface.

[0056] The control unit 3 can be a microcontroller, which controls the forward and reverse rotation of the peristaltic pump 23, the opening and closing of the two control valves, receives and outputs the weight data acquired by the electronic balance, communicates with the host computer and has a manual operation interface. Through the combination of the above functions, the process of gradually diluting the solution from high concentration to low concentration in the Ubbelohde viscometer test is realized.

[0057] The initial concentration of the solution in the Ubbelohde viscometer is pre-input into the host computer. The rotation duration of the peristaltic pump 23 affects the volumetric flow rate or mass flow rate of the pumped solvent or the pumped solution, which can be set according to the test requirements. The host computer receives the initial and final mass data obtained from the control unit, calculates the weight of the pumped or pumped liquid, and thus calculates the amount and concentration of the solution in the Ubbelohde viscometer.

[0058] Meanwhile, once the device is assembled, the length and inner diameter of the pipes connecting each unit and component are known. The volume of liquid that can be contained in the pipe can be calculated from the pipe length and inner diameter, or it can be determined in advance through experiments (the volume of the cleaning medium used can be measured during the cleaning stage), thereby reducing the impact of pipe residue on subsequent results. Similarly, the volume of liquid contained inside the tee joint can be measured or calculated in advance, and the selected peristaltic pump and electromagnetic clamp valve do not directly contact the medium, so they have almost no impact on the subsequent dilution accuracy.

[0059] The aforementioned device connects the control valve and solution drive unit to the port of the Ubbelohde viscometer for solution dilution via a three-way connector and pipe. In conjunction with the control unit and electronic balance, it can quantitatively inject liquid into or extract liquid from the Ubbelohde viscometer. The amount of solvent used for dilution is much smaller than that of traditional manual methods, and it has relatively higher accuracy.

[0060] This device allows for "infinite dilution." In actual testing, the initial solution concentration is always prepared slightly higher than normal. However, if the concentration is too high, using traditional testing methods, only the last few data points can be used for linear fitting; the initial data points deviate from the assumptions of the "dilute solution theory" and do not show a linear relationship. Under traditional testing methods, this situation is unavoidable due to the limited volume of the reservoir. This device, however, achieves "infinite dilution" by quantitatively extracting the solution and adding solvent. Even if the initial concentration of the solution is high, it will not affect subsequent viscosity tests; simply repeating the process multiple times will bring the solution into a reasonable concentration range, allowing the data points to show a linear relationship.

[0061] A balance with a precision of 0.1% or 0.01% is a standard instrument in the laboratory. It can easily and accurately weigh solvents to a volume of 0.1 mg. 0.1 mg corresponds to a solution volume of 0.0001 mL, a precision far exceeding that of graduated pipettes, burettes, and other glass instruments. A balance with a precision of 0.01% offers even greater accuracy.

[0062] Example 2:

[0063] The working method of the above-mentioned device includes the following steps:

[0064] Injecting solvent into the Ubbelohde viscometer and extracting liquid from the Ubbelohde viscometer.

[0065] In this embodiment, when the liquid is drawn from the Ubbelohde viscometer:

[0066] (1) The control unit 3 reads the initial mass data through the electronic balance 4;

[0067] (2) The first control valve 11 is closed and the second control valve 12 is open;

[0068] (3) The peristaltic pump 23 reverses the set time and draws liquid from the Ubbelohde viscometer into the waste liquid bottle 22;

[0069] (4) The peristaltic pump 23 rotates forward for a set time to drain the residual solution in the pipeline;

[0070] (5) The first control valve 11 is opened;

[0071] (6) After a set time has elapsed and the data has stabilized, the control unit 3 reads the mass data at the end of the process.

[0072] (7) Calculate the weight of the pumped liquid from the initial and final mass data, and thus calculate the amount and concentration of the remaining liquid in the Ubbelohde viscometer (the initial concentration of the solution in the Ubbelohde viscometer is known).

[0073] In this embodiment, when injecting solvent into the Ubbelohde viscometer:

[0074] (1) The control system reads the initial mass data;

[0075] (2) The first control valve 11 is open and the second control valve 12 is closed;

[0076] (3) The peristaltic pump 23 rotates forward for a set time to draw liquid from the solvent bottle 21 into the Ubbelohde viscometer;

[0077] (4) The first control valve 11 is closed and the second control valve 12 is open;

[0078] (5) The peristaltic pump 23 continues to rotate forward for the set time to empty the pipeline;

[0079] (6) The first control valve 11 is opened;

[0080] (7) After a set time has elapsed and the data has stabilized, the control unit 3 reads the mass data at the end of the process.

[0081] (8) Calculate the weight of the pumped liquid from the initial and final mass data, and thus calculate the amount and concentration of the solution in the Ubbelohde viscometer (the initial concentration of the solution in the Ubbelohde viscometer is known).

[0082] During Ubbelohde viscometer testing, after a certain concentration test is completed, the device, according to instructions from the host computer or manual control, combines the extraction and injection of liquid operations according to a pre-set combination to dilute the solution in the Ubbelohde viscometer to a certain concentration. After the test at this concentration is completed, the previous steps are repeated to dilute the solution in the Ubbelohde viscometer to the next concentration.

[0083] According to the test, this device can significantly save solvent, and the comparison results are shown in Table 1.

[0084] Table 1: Comparison Results of This Device and Traditional Manual Operation

[0085]

[0086] Therefore, this implementation allows for the quantitative addition or extraction of solvent from the Ubbelohde viscometer, provided the solution is already in place. The quantitative method utilizes a precision electronic balance to calculate the mass change, resulting in high accuracy.

[0087] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A solution dilution device based on Ubbelohde viscometer testing, characterized in that, include: The liquid inlet / outlet unit includes a three-way connector; interface A of the three-way connector is connected to one end of the solution drive unit via a pipe, and the other end of the solution drive unit is connected to the liquid inlet pipe of the Ubbelohde viscometer; interface B is connected to the solvent bottle via a pipe through a first control valve; and interface C is connected to the waste liquid bottle via a pipe through a second control valve. The liquid dispensing unit includes a solvent bottle and a waste liquid bottle mounted on an electronic balance. The weight data acquired by the electronic balance is sent to the control unit. The control unit is used to control the operation of the solution drive, the first control valve and the second control valve, receive the weight data obtained by the liquid metering unit and send it to the host computer. The host computer outputs the data of the diluted solution based on the initial concentration of the solution in the Ubbelohde viscometer and the received weight data. When injecting solvent into the Ubbelohde viscometer: the first control valve opens, the second control valve closes, the solution drive rotates forward for a set time, and the liquid is drawn from the solvent bottle into the Ubbelohde viscometer; the first control valve closes, the second control valve opens, the solution drive continues to rotate forward for a set time, and the pipeline is emptied. When liquid is drawn from the Ubbelohde viscometer: the first control valve is closed and the second control valve is opened; the solution drive reverses for a set time to draw liquid from the Ubbelohde viscometer into the waste bottle; the solution drive rotates forward for a set time to drain the residual solution in the pipeline.

2. The solution dilution device based on Ubbelohde viscometer testing as described in claim 1, characterized in that, One end of the first control valve is connected to interface B of the tee connector via a pipe, and the other end of the first control valve is connected to the solvent bottle via a pipe.

3. The solution dilution device based on Ubbelohde viscometer testing as described in claim 1, characterized in that, One end of the second control valve is connected to the interface C of the tee connector via a pipe, and the other end of the second control valve is connected to the waste liquid bottle via a pipe.

4. The solution dilution device based on Ubbelohde viscometer testing as described in claim 1, characterized in that, The tube connecting to the solvent bottle extends into the bottle, with the tube opening below the liquid level inside the bottle.

5. The solution dilution device based on Ubbelohde viscometer testing as described in claim 1, characterized in that, The pipe connecting the waste liquid bottle extends into the bottle, with the pipe opening positioned below the bottle opening and above the liquid level inside the bottle at a predetermined height.

6. The solution dilution device based on Ubbelohde viscometer testing as described in claim 1, characterized in that, The Ubbelohde viscometer includes an inlet tube, a vent tube, and a measuring tube. The bottom end of the inlet tube is connected to the main reservoir ball, and the bottom ends of the vent tube and the measuring tube are connected to a buffer ball and are also connected to the main reservoir ball. The measuring tube is provided with an upper reservoir ball, a measuring ball, and a capillary tube in sequence from the tube opening to the bottom of the tube. There is an upper graduation line between the measuring ball and the upper reservoir ball, and a lower graduation line between the measuring ball and the capillary tube.

7. The solution dilution device based on Ubbelohde viscometer testing as described in claim 6, characterized in that, The pipe connecting the Ubbelohde viscometer inlet extends into the main reservoir, with the inlet located below the liquid level inside the main reservoir.

8. The solution dilution device based on Ubbelohde viscometer testing as described in claim 1, characterized in that, The host computer outputs the amount of solvent pumped in or out by the solution drive based on the difference between the received initial weight and the final weight, and determines the data after dilution based on the initial concentration of the solution in the Ubbelohde viscometer.

9. A method of operating the apparatus according to any one of claims 1-8, characterized in that, Includes the following steps: When injecting solvent into the Ubbelohde viscometer: The control unit obtains initial mass data via an electronic balance; The first control valve opens, the second control valve closes, the solution drive rotates forward for a set time, and the liquid is drawn from the solvent bottle into the Ubbelohde viscometer. The first control valve is closed, the second control valve is opened, and the solution drive continues to rotate forward for the set time to empty the pipeline. The first control valve opens, and after a set time, the control unit acquires the mass data at the end. By using the initial and final mass data, as well as the initial concentration of the solution in the Ubbelohde viscometer, the weight of the pumped liquid, the volume of the solution in the Ubbelohde viscometer, and the concentration are obtained.

10. A method of operating the apparatus according to any one of claims 1-8, characterized in that, Includes the following steps: When liquid is drawn from the Ubbelohde viscometer: The control unit obtains initial mass data via an electronic balance; The first control valve is closed, and the second control valve is opened; the solution drive reverses the set time to extract liquid from the Ubbelohde viscometer into the waste bottle; The solution drive rotates forward for a set time to drain the residual solution from the pipeline; The first control valve opens, and after a set time, the control unit acquires the mass data at the end. By using the initial and final mass data, as well as the initial concentration of the solution in the Ubbelohde viscometer, the weight of the pumped liquid, the amount and concentration of the remaining liquid in the Ubbelohde viscometer are obtained.

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