Real-time detection device for hydroxyl value of acrylate monomer

Abstract

The utility model discloses a real-time detection device for a hydroxyl value of an acrylate monomer. Comprising a reaction kettle, a first infusion pump, a lifting device, a test electrode, a sampling tube, a solvent dripping tube, a reaction reagent dripping tube, a titrating solution dripping tube, a distilled water dripping tube, a waste liquid suction tube, a sample disc, a sample cup, a second infusion pump, a solvent storage tank, a third infusion pump, a reaction reagent storage tank, a fourth infusion pump, a titrating solution storage tank, a fifth infusion pump and a distilled water storage tank, and an infusion pump and a waste liquid storage tank. According to the device, the conversion from intermittent monitoring to continuous monitoring in the production process is realized, and the accuracy and the flexibility of process control are greatly improved; the reaction monitoring period is obviously shortened, the manual intervention and waiting time are reduced, and the production process is more continuous and efficient; by accurately controlling the reaction conditions, the product quality problem caused by incomplete reaction or excessive reaction is effectively avoided, and the stability and consistency of the product are improved; and the working environment is improved.

Description

Technical Field

[0001] The utility model relates to a device for real-time detection of the hydroxyl value of acrylate monomers, belonging to the field of analytical detection equipment. Background Technique

[0002] As an important type of organic chemical raw material, acrylate monomers have shown broad application prospects in many fields such as coatings, adhesives, inks, 3D printing, and photovoltaic materials due to their excellent physical and chemical properties. Among them, special acrylate monomers have particularly complex production processes due to their unique molecular structures and functional characteristics, and synthesizing such monomers through transesterification reactions is a key path.

[0003] In the production process of special acrylate monomers, the transesterification reaction is a key step, but its reaction process is often difficult to directly and real-time monitor. Currently, the commonly used method in the industry is the hydroxyl value titration method based on national standards GB / T 7838-2007 and GB / T 12008.3-2009. This method determines the change in hydroxyl value in the reaction system through intermittent sampling and titration analysis, thereby indirectly inferring the reaction progress. However, the limitation of this method is that it cannot provide continuous and timely reaction information, easily leading to lag in reaction control, affecting product quality and production efficiency. Moreover, the volatilization of organic solvents (such as pyridine) during sampling and titration will pollute the environment and affect human health. Content of the Utility Model

[0004] The utility model provides a device for online real-time detection of hydroxyl value, connecting the hydroxyl value detection device with a reaction kettle to realize real-time and continuous monitoring of the hydroxyl value in the reaction system; by real-time monitoring the change in hydroxyl value, the device can accurately monitor the reaction process and provide timely and accurate data support for process control; at the same time, it reduces the environmental pollution and the impact on human health caused by sampling.

[0005] To solve the above technical problems, the technical solutions adopted by the utility model are as follows:

[0006] A device for real-time detection of the hydroxyl value of acrylate monomers, comprising a reaction kettle, a first infusion pump, a lifting device, a test electrode, a sampling tube, a solvent dropping tube, a reaction reagent dropping tube, a titrant dropping tube, a distilled water dropping tube, a waste liquid suction tube, a sample tray, a sample cup, a second infusion pump, a solvent storage tank, a third infusion pump, a reaction reagent storage tank, a fourth infusion pump, a titrant storage tank, a fifth infusion pump, a distilled water storage tank, a liquid extraction pump, and a waste liquid storage tank;

[0007] The bottom of the reaction kettle, the first infusion pump, and the sampling tube are sequentially connected through pipelines;

[0008] The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are all arranged on the lifting device and can move up and down respectively under the drive of the lifting device; control valves are respectively provided on the sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, and distilled water dropping tube.

[0009] The sample cup is located on the sample tray; the sample cup is located below the test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube.

[0010] The solvent dropping tube, second infusion pump, and solvent storage tank are sequentially connected through pipelines; the reaction reagent dropping tube, third infusion pump, and reaction reagent storage tank are sequentially connected through pipelines; the titrant dropping tube, fourth infusion pump, and titrant storage tank are sequentially connected through pipelines; the distilled water dropping tube, fifth infusion pump, and distilled water storage tank are sequentially connected through pipelines; the waste liquid suction tube, liquid extraction pump, and waste liquid storage tank are sequentially connected through pipelines.

[0011] During use, the material in the reaction kettle is input into the sample cup on the sample tray through the first infusion pump via the connecting pipeline and the sampling tube, and then the solvent, reaction reagent, titrant, and distilled water in the solvent storage tank, reaction reagent storage tank, titrant storage tank, and distilled water storage tank are respectively added into the sample cup through the second infusion pump, third infusion pump, fourth infusion pump, and fifth infusion pump as needed, and the test is carried out using the test electrode; after one test is completed, the liquid extraction pump is started to suck the liquid in the sample cup into the waste liquid storage tank.

[0012] For the reagents such as the test solvent, reaction reagent, titrant, and distilled water required for the hydroxyl value test in this application, referring to the prior art, this application has no special selection and will not be elaborated here.

[0013] The above device can continuously and timely reflect the hydroxyl value, which is beneficial to the control of product quality and the improvement of production efficiency; moreover, there is no need for manual sampling, the liquid transportation is carried out through a closed pipeline, and after the test is completed, the test liquid can be timely sucked into the waste liquid storage tank, reducing environmental pollution and the impact on human health.

[0014] The first infusion pump is used to sample from the reaction kettle and transport it to the sample cup. The liquid extraction pump is used to pump the liquid in the sample cup after the test into the waste liquid storage tank.

[0015] The above-mentioned test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube and waste liquid suction tube are all arranged on a lifting device and can be moved up and down respectively under the drive of the lifting device. That is to say, any one of the test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube and waste liquid suction tube can be moved up and down independently. That is, there are 6 independent lifting drive structures on the lifting device, and the test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube and waste liquid suction tube are respectively connected to the 6 lifting drive structures.

[0016] When sampling is required, the corresponding lifting drive structure moves the sampling tube downward until the bottom of the sampling tube extends into the sample cup. Open the control valve and the first infusion pump on the sampling tube to start sampling. After sampling is completed, the first infusion pump stops running, and the corresponding lifting drive structure moves the sampling tube upward to the original position, and at the same time closes the control valve on the sampling tube; when it is necessary to add solvent to the sample cup, the corresponding lifting drive structure moves the solvent dropping tube downward until the bottom of the solvent dropping tube extends into the sample cup. Open the control valve and the second infusion pump on the solvent dropping tube to start dropping. After the solvent addition is completed, the second infusion pump stops running, and the corresponding lifting drive structure moves the solvent dropping tube upward to the original position, and at the same time closes the control valve on the solvent dropping tube; when it is necessary to add reaction reagent to the sample cup, the corresponding lifting drive structure moves the reaction reagent dropping tube downward until the bottom of the reaction reagent dropping tube extends into the sample cup. Open the control valve and the third infusion pump on the reaction reagent dropping tube to start dropping. After the reaction reagent addition is completed, the third infusion pump stops running, and the corresponding lifting drive structure moves the reaction reagent dropping tube upward to the original position, and at the same time closes the control valve on the reaction reagent dropping tube; when it is necessary to add distilled water to the sample cup, the corresponding lifting drive structure moves the distilled water dropping tube downward until the bottom of the distilled water dropping tube extends into the sample cup. Open the control valve and the fifth infusion pump on the distilled water dropping tube to start dropping. After the distilled water addition is completed, the fifth infusion pump stops running, and the corresponding lifting drive structure moves the distilled water dropping tube upward to the original position, and at the same time closes the control valve on the distilled water dropping tube; when it is necessary to add titrant to the sample cup, the corresponding lifting drive structure moves the titrant dropping tube downward until the bottom of the titrant dropping tube extends into the sample cup. Open the control valve and the fourth infusion pump on the titrant dropping tube to start dropping. After the titrant addition is completed, the fourth infusion pump stops running, and the corresponding lifting drive structure moves the titrant dropping tube upward to the original position, and at the same time closes the control valve on the titrant dropping tube.

[0017] In the above-mentioned solvent storage tank, reaction reagent storage tank, titrant storage tank and distilled water storage tank, the test solvent, reaction reagent, titrant and distilled water required for testing are respectively contained. The waste liquid storage tank is used to suck the liquid in the sample cup after the test is completed.

[0018] In this application, continuous monitoring is a relative term. In one reaction, absolute continuous monitoring is not required. After a certain period of time has elapsed since the end of one measurement, the next measurement can be continuously initiated.

[0019] For the convenience of control, the above real-time detection device for the hydroxyl value of acrylate monomers further includes a control system. The first infusion pump, lifting device, test electrode, second infusion pump, third infusion pump, fourth infusion pump, fifth infusion pump, liquid extraction pump, and each control valve are all connected to the control system and controlled by the control system.

[0020] The above control system is equipped with a status display and parameter setting display, which can perform functions such as setting of test program methods, data calculation, and result display.

[0021] This application does not have any special improvements to the structure and control method of the control system, and existing products can be directly used, so it will not be elaborated here.

[0022] The above first infusion pump, second infusion pump, third infusion pump, fourth infusion pump, and fifth infusion pump are all constant-pressure infusion pumps; the liquid extraction pump is a constant-pressure liquid extraction pump. Each constant-pressure infusion pump has a high-precision metering function for the volume of liquid delivery, and is used for the delivery and metering of reaction liquid, solvent, reaction reagent, titrant, and distilled water. The constant-pressure infusion pump and the constant-pressure liquid extraction pump can be directly purchased as existing products, and this application does not have any special improvements to them, so it will not be elaborated here.

[0023] The above lifting device includes a support frame. There are 6 independent lifting drive structures on the support frame. The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are respectively connected to the 6 lifting drive structures. Each lifting drive structure is connected to the control system and controlled by the control system.

[0024] The above-mentioned lifting drive structure can be an orbital slider structure. The lifting drive structure includes an orbit and a slider. The orbit is vertically installed on the support frame, and the slider is slidably fitted on the orbit and moves up and down along the orbit under the control of the system. The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are respectively connected to the sliders of the corresponding lifting drive structures and move up and down driven by the sliders. Alternatively, the lifting drive structure can also be a lifting track structure. The track is vertically installed on the support frame and can rotate bidirectionally under the control of the system. The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are respectively connected to one side of the track of the corresponding lifting drive structure. The track moves back and forth bidirectionally, thereby driving the test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, or waste liquid suction tube to move up and down. The running range of the track, that is, the distance that the connected components (such as the test electrode) are brought from the highest position to the lowest position or from the lowest temperature to the highest position. Alternatively, the lifting drive structure can also be a folding lifting frame structure. The folding lifting frame is installed on the support frame and can be telescoped under the control of the system. The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are respectively connected to the bottom of the folding lifting frame of the corresponding lifting drive structure. The folding lifting frame telescopes, thereby driving the test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, or waste liquid suction tube to move up and down. Of course, the lifting drive structure can also adopt other existing structures.

[0025] For the convenience of X and Y direction adjustment, the lifting device further includes an XY moving mechanism. The top of the support frame is installed on the XY moving mechanism. The XY moving mechanism is connected to the control system and controlled by the control system. Driven by the XY moving mechanism, each lifting drive structure can move along the X direction and the Y direction. As a specific implementation solution of the XY moving mechanism, the XY moving mechanism includes an X-direction support, an X-direction motor, an X-direction lead screw, an X-direction slider, a Y-direction support, a Y-direction motor, a Y-direction lead screw, and a Y-direction slider. The X-direction support is installed on the support surface at the site (if there is no convenient support surface at the site, a support can be set, and a support surface can be set on the top of the support, the purpose is to ensure the smooth movement of the X-direction slider along the X-direction slide rail). The X-direction lead screw is installed on the X-direction support, the X-direction motor is installed on the X-direction support, and the X-direction motor is connected to one end of the X-direction lead screw through a coupling. Driven by the X-direction motor, the X-direction lead screw can rotate. The X-direction slider is in threaded fit with the X-direction lead screw. In this way, when the X-direction motor drives the X-direction lead screw to rotate, it will drive the X-direction slider to move along the length direction of the X-direction lead screw. The Y-direction support is installed on the X-direction slider, the Y-direction lead screw is installed on the Y-direction support, the Y-direction motor is installed on the Y-direction support, and the Y-direction motor is connected to one end of the Y-direction lead screw through a coupling. Driven by the Y-direction motor, the Y-direction lead screw can rotate. The Y-direction slider is in threaded fit with the Y-direction lead screw. In this way, when the Y-direction motor drives the Y-direction lead screw to rotate, it will drive the Y-direction slider to move along the length direction of the Y-direction lead screw. The top of the support frame is installed on the Y-direction slider. Of course, the XY moving mechanism can adopt other existing structures.

[0026] For the convenience of testing, there are more than two positioning holes on the sample tray, and the number of sample cups is more than two. The sample cups are placed in the positioning holes, and there is only one sample cup in each positioning hole. This facilitates the monitoring of the materials in multiple reaction kettles.

[0027] A magnetic stirrer is provided at the bottom of each of the above-mentioned positioning holes, and a polytetrafluoroethylene magnetic stirrer rotor is provided in each sample cup.

[0028] A high-precision weighing sensor is also provided at the bottom of each of the above-mentioned positioning holes. When sampling, when the weight of the sample in the sample cup reaches the set weight, the first infusion pump stops running and the magnetic stirrer starts to stir.

[0029] For components such as the control system, weighing sensor, magnetic stirrer, and test electrode, according to the on-site measurement requirements, existing commercially available products can be directly purchased. This application does not improve the structure of these components themselves, so no further description is given. The test electrode is a composite electrode (composite with a measuring electrode, a reference electrode, and a solution grounding electrode), and there is a lithium chloride-ethanol or tetraethylammonium bromide ethylene glycol reference solution inside. The composite electrode is a pH composite glass electrode.

[0030] The materials used for the above-mentioned solvent storage tank, reaction reagent storage tank, titrant storage tank and distilled water storage tank are all brown glass. This can not only ensure corrosion resistance, but also reduce the decomposition, volatilization, etc. of substances.

[0031] In order to facilitate the cleaning of waste liquid, a liquid outlet is provided at the bottom of the waste liquid storage tank, and a control valve is provided on the liquid outlet. Technologies not mentioned in the present utility model shall refer to the prior art.

[0032] The real-time detection device for the hydroxyl value of acrylate monomers of the present utility model has the following beneficial effects:

[0033] 1) It can achieve real-time and precise control: realizing the transformation of the production process from "intermittent monitoring" to "continuous monitoring", greatly improving the precision and flexibility of process control.

[0034] 2) It improves production efficiency: The application of the real-time detection device significantly shortens the reaction monitoring cycle, reduces manual intervention and waiting time, making the production process more continuous and efficient.

[0035] 3) It improves product quality: By precisely controlling the reaction conditions, effectively avoiding product quality problems caused by incomplete or excessive reactions, improving the stability and consistency of products.

[0036] 4) It improves the working environment: Realizing the closed transportation of the whole process of sampling, titration, waste liquid treatment, etc., reducing or avoiding the emission of harmful solvents, and reducing environmental pollution and the impact on human health. Description of the Drawings

[0037] Figure 1 It is a schematic structural diagram of the real-time detection device for the hydroxyl value of acrylate monomers of the present utility model;

[0038] In the figure, 1 is a reaction kettle, 2 is a first infusion pump, 3 is a lifting device, 4 is a test electrode, 5 is a sampling tube, 6 is a solvent dropping tube, 7 is a reaction reagent dropping tube, 8 is a titrant dropping tube, 9 is a distilled water dropping tube, 10 is a waste liquid suction tube, 11 is a sample tray, 111 is a positioning hole, 12 is a second infusion pump, 13 is a solvent storage tank, 14 is a third infusion pump, 15 is a reaction reagent storage tank, 16 is a fourth infusion pump, 17 is a titrant storage tank, 18 is a fifth infusion pump, 19 is a distilled water storage tank, 20 is a liquid extraction pump, 21 is a waste liquid storage tank, and 22 is a control system. Detailed Embodiments

[0039] In order to better understand the present utility model, the content of the present utility model will be further clarified below in conjunction with embodiments, but the content of the present utility model is not limited to the following embodiments only.

[0040] In this application, orientation terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" are relative orientations or position relationships based on the figures shown or the state of use, and are only for the convenience of describing this application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0041] Example 1

[0042] As Figure 1 shown, a real-time detection device for the hydroxyl value of an acrylate monomer includes a reaction kettle, a first infusion pump, a lifting device, a test electrode, a sampling tube, a solvent dropping tube, a reaction reagent dropping tube, a titrant dropping tube, a distilled water dropping tube, a waste liquid suction tube, a sample tray, a sample cup, a second infusion pump, a solvent storage tank, a third infusion pump, a reaction reagent storage tank, a fourth infusion pump, a titrant storage tank, a fifth infusion pump, a distilled water storage tank, a liquid extraction pump, and a waste liquid storage tank;

[0043] The bottom of the reaction kettle, the first infusion pump, and the sampling tube are sequentially connected through pipelines;

[0044] The test electrode, the sampling tube, the solvent dropping tube, the reaction reagent dropping tube, the titrant dropping tube, the distilled water dropping tube, and the waste liquid suction tube are all arranged on the lifting device and can be moved up and down respectively under the drive of the lifting device; control valves are respectively provided on the sampling tube, the solvent dropping tube, the reaction reagent dropping tube, the titrant dropping tube, and the distilled water dropping tube;

[0045] The sample cup is located on the sample tray; the sample cup is located below the test electrode, the sampling tube, the solvent dropping tube, the reaction reagent dropping tube, the titrant dropping tube, the distilled water dropping tube, and the waste liquid suction tube;

[0046] The solvent dropping tube, the second infusion pump, and the solvent storage tank are sequentially connected through pipelines; the reaction reagent dropping tube, the third infusion pump, and the reaction reagent storage tank are sequentially connected through pipelines; the titrant dropping tube, the fourth infusion pump, and the titrant storage tank are sequentially connected through pipelines; the distilled water dropping tube, the fifth infusion pump, and the distilled water storage tank are sequentially connected through pipelines; the waste liquid suction tube, the liquid extraction pump, and the waste liquid storage tank are sequentially connected through pipelines. In the solvent storage tank, the reaction reagent storage tank, the titrant storage tank, and the distilled water storage tank, the test solvent, the reaction reagent, the titrant, and the distilled water required for testing are respectively contained. The waste liquid storage tank is used to suck the liquid in the sample cup after the test is completed. The materials used for the solvent storage tank, the reaction reagent storage tank, the titrant storage tank, and the distilled water storage tank are all brown glass.

[0047] In use, the materials in the reaction kettle are input into the sample cups on the sample tray through the first infusion pump, the connecting pipeline and the sampling pipe. Then, according to needs, solvents, reaction reagents, titrants and distilled water in the solvent storage tank, reaction reagent storage tank, titrant storage tank and distilled water storage tank are added into the sample cups through the second infusion pump, the third infusion pump, the fourth infusion pump and the fifth infusion pump respectively, and the test electrode is used for testing. After one test is completed, the liquid in the sample cup is sucked into the waste liquid storage tank by starting the liquid extraction pump.

[0048] The above device can continuously and timely reflect the hydroxyl value, which is beneficial to the control of product quality and the improvement of production efficiency. Moreover, there is no need for manual sampling. The liquid is transported through a closed pipeline, and after the test is completed, the test liquid can be timely sucked into the waste liquid storage tank, reducing environmental pollution and the impact on human health.

[0049] Example 2

[0050] On the basis of Example 1, the following further improvements are made: for the convenience of control, the real-time detection device for the hydroxyl value of the above acrylate monomer further includes a control system. The first infusion pump, the lifting device, the test electrode, the second infusion pump, the third infusion pump, the fourth infusion pump, the fifth infusion pump, the liquid extraction pump and each control valve are all connected to the control system and controlled by the control system, so as to realize automatic control. The above control system is equipped with a status display and parameter setting display, which can perform functions such as setting of test program methods, data calculation and result display.

[0051] Example 3

[0052] On the basis of Example 2, the following further improvements are made: the first infusion pump, the second infusion pump, the third infusion pump, the fourth infusion pump and the fifth infusion pump are all constant-pressure infusion pumps; the liquid extraction pump is a constant-pressure liquid extraction pump. Each constant-pressure infusion pump is equipped with a high-precision metering function for volume metering, which is used for the transportation and metering of reaction liquids, solvents, reaction reagents, titrants and distilled water.

[0053] Example 4

[0054] On the basis of Example 3, the following further improvements are made: the lifting device includes a support frame, and 6 independent lifting drive structures are provided on the support frame. The test electrode, the sampling pipe, the solvent dropping pipe, the reaction reagent dropping pipe, the titrant dropping pipe, the distilled water dropping pipe and the waste liquid suction pipe are respectively connected to the 6 lifting drive structures, and each lifting drive structure is connected to the control system and controlled by the control system.

[0055] The above lifting drive structure can be an orbital slider structure. The lifting drive structure includes an orbit and a slider. The orbit is vertically installed on the support frame, and the slider is slidably fitted on the orbit and moves up and down along the orbit under the control of the system. The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are respectively connected to the sliders of the corresponding lifting drive structures and move up and down driven by the sliders. Alternatively, the lifting drive structure can also be a folding lifting frame structure. The folding lifting frame is installed on the support frame and can be telescoped under the control of the system. The test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, and waste liquid suction tube are respectively connected to the bottom of the folding lifting frame of the corresponding lifting drive structure. The folding lifting frame telescopes, thereby driving the test electrode, sampling tube, solvent dropping tube, reaction reagent dropping tube, titrant dropping tube, distilled water dropping tube, or waste liquid suction tube to move up and down. Of course, other existing structures can also be adopted for the lifting drive structure.

[0056] Example 5

[0057] On the basis of Example 4, the following further improvements are made: To facilitate X and Y direction adjustment, the lifting device further includes an XY moving mechanism. The top of the support frame is installed on the XY moving mechanism. The XY moving mechanism is connected to the control system and controlled by the control system. Driven by the XY moving mechanism, each lifting drive structure can move in the X direction and the Y direction. As a specific implementation solution of the XY moving mechanism, the XY moving mechanism includes an X-direction support, an X-direction motor, an X-direction lead screw, an X-direction slider, a Y-direction support, a Y-direction motor, a Y-direction lead screw, and a Y-direction slider. The X-direction support is installed on the support surface at the site (if there is no convenient support surface at the site, a support can be set, and a support surface can be set at the top of the support to ensure the smooth movement of the X-direction slider along the X-direction slide rail). The X-direction lead screw is installed on the X-direction support, and the X-direction motor is installed on the X-direction support. The X-direction motor is connected to one end of the X-direction lead screw through a coupling, and the X-direction lead screw can rotate driven by the X-direction motor. The X-direction slider is in threaded fit with the X-direction lead screw. In this way, when the X-direction motor drives the X-direction lead screw to rotate, it will drive the X-direction slider to move along the length direction of the X-direction lead screw. The Y-direction support is installed on the X-direction slider. The Y-direction lead screw is installed on the Y-direction support, and the Y-direction motor is installed on the Y-direction support. The Y-direction motor is connected to one end of the Y-direction lead screw through a coupling, and the Y-direction lead screw can rotate driven by the Y-direction motor. The Y-direction slider is in threaded fit with the Y-direction lead screw. In this way, when the Y-direction motor drives the Y-direction lead screw to rotate, it will drive the Y-direction slider to move along the length direction of the Y-direction lead screw. The top of the support frame is installed on the Y-direction slider. Of course, other existing structures can also be adopted for the XY moving mechanism.

[0058] Example 6

[0059] On the basis of Example 5, the following further improvements were made: For the convenience of testing, six positioning holes are provided on the sample tray, and the number of sample cups is six, which are respectively placed in the six positioning holes. This facilitates the monitoring of the materials in multiple reaction kettles. A magnetic stirrer and a high-precision weighing sensor are provided at the bottom of each positioning hole, and a polytetrafluoroethylene magnetic stirrer rotor is provided in each sample cup. Both the magnetic stirrer and the high-precision weighing sensor are connected to the control system and controlled by the control system. The test electrode is a pH composite glass electrode, which contains a lithium chloride-ethanol or tetraethylammonium bromide ethylene glycol reference solution. During sampling, when the weight of the sample in the sample cup reaches the set weight, the first infusion pump stops running, the control valve on the sampling pipe closes, and the magnetic stirrer starts to stir. For the convenience of cleaning the waste liquid, a liquid outlet is provided at the bottom of the waste liquid storage tank, and a control valve is provided on the liquid outlet.

[0060] 1,6-Hexanediol reacts with methyl acrylate to synthesize 1,6-hexanediol diacrylate, and the reaction duration is 13 hours. Set up the program method in the control system. At the initial stage of the reaction, the hydroxyl value of the reaction system is monitored every hour. After 7 hours of reaction, the hydroxyl value of the reaction system is monitored every 30 minutes until the end of the reaction. At the start of the reaction, the equipment lifting device drives the sampling pipe, test electrode and dropping pipe to descend to the measurement position. 1.0 g of the sample is taken into the test sample cup through the first infusion pump, and the weighing sensor automatically records the product quality. Then, 20 mL of the solvent methanol solution is added to the test sample cup through the second infusion pump, and stirring is started to completely dissolve the sample. Then, 10 mL of a 0.1 mol / L acetonitrile solution of the reaction reagent 4-chlorobenzenesulfonyl isocyanate is added to the test sample cup through the third infusion pump, and stirring is continued for 5 minutes to complete the reaction. Then, 0.75 mL of distilled water is added to the test sample cup through the fifth infusion pump to quench the unreacted acetonitrile solution of 4-chlorobenzenesulfonyl isocyanate. After continuing to stir for 1 minute, 30 mL of the solvent methanol solution is added to the test sample cup through the second infusion pump. Finally, the titrant N,N,N-tributyl-1-butylammonium hydroxide methanol solution is controlled by the fourth infusion pump, and titration starts according to the program set method. After the titration is completed, the control system automatically calculates and records the hydroxyl value as 224.66 mg KOH / g. After the test is completed, the reaction waste liquid in the measuring cup is transported to the waste liquid bottle through the liquid extraction pump. Then, according to the program set method, the above test is automatically started every certain period of time until the hydroxyl value at the end of the reaction < 10 mg KOH / g, and the hydroxyl value is recorded. See Table 1 for details.

[0061] Table 1 Record of hydroxyl value test during the reaction

[0062] Reaction time / h Hydroxyl value mg KOH / g Reaction time / h Hydroxyl value mg KOH / g 0 224.66 8.5 44.28 1 183.52 9.0 38.51 2 146.76 9.5 32.58 3 115.64 10.0 27.12 4 98.58 10.5 23.46 5 84.95 11.0 18.97 6 73.57 11.5 15.28 7 61.59 12.0 11.59 7.5 55.63 12.5 8.57 8.0 49.52 13.0 7.26

[0063] The real-time detection device for the hydroxyl value of acrylate monomers in the above examples can achieve real-time and precise control: it realizes the transformation of the production process from "intermittent monitoring" to "continuous monitoring", greatly improving the precision and flexibility of process control. It improves production efficiency: the application of the real-time detection device significantly shortens the reaction monitoring cycle, reduces manual intervention and waiting time, making the production process more continuous and efficient. It enhances product quality: by precisely controlling the reaction conditions, it effectively avoids product quality problems caused by incomplete or excessive reactions, improving the stability and consistency of products. It improves the working environment: it realizes the closed transportation of the whole process such as sampling, titration, and waste liquid treatment, reducing or avoiding the emission of harmful solvents.

Claims

1. A real-time detection device for the hydroxyl value of an acrylate monomer, characterized in that: The invention comprises a reaction kettle (1), a first infusion pump (2), a lifting device (3), a test electrode (4), a sampling tube (5), a solvent dropping tube (6), a reaction reagent dropping tube (7), a titration liquid dropping tube (8), a distilled water dropping tube (9), a waste liquid suction tube (10), a sample tray (11), a sample cup, a second infusion pump (12), a solvent storage tank (13), a third infusion pump (14), a reaction reagent storage tank (15), a fourth infusion pump (16), a titration liquid storage tank (17), a fifth infusion pump (18), a distilled water storage tank (19), a liquid extraction pump (20) and a waste liquid storage tank (21); The bottom of the reaction kettle (1), the first infusion pump (2) and the sampling tube (5) are connected in sequence through pipelines; The test electrode (4), the sampling tube (5), the solvent dropping tube (6), the reaction reagent dropping tube (7), the titration liquid dropping tube (8), the distilled water dropping tube (9) and the waste liquid suction tube (10) are all arranged on the lifting device (3) and can move up and down respectively under the drive of the lifting device (3); the sampling tube (5), the solvent dropping tube (6), the reaction reagent dropping tube (7), the titration liquid dropping tube (8) and the distilled water dropping tube (9) are respectively provided with control valves; The sample cup is located on the sample tray (11); the sample cup is located below the test electrode (4), the sampling tube (5), the solvent dropping tube (6), the reaction reagent dropping tube (7), the titration liquid dropping tube (8), the distilled water dropping tube (9) and the waste liquid suction tube (10); The solvent dripping tube (6), the second infusion pump (12) and the solvent storage tank (13) are connected in sequence through a pipeline; the reaction reagent dripping tube (7), the third infusion pump (14) and the reaction reagent storage tank (15) are connected in sequence through a pipeline; the titrant dripping tube (8), the fourth infusion pump (16) and the titrant storage tank (17) are connected in sequence through a pipeline; the distilled water dripping tube (9), the fifth infusion pump (18) and the distilled water storage tank (19) are connected in sequence through a pipeline; and the waste liquid suction tube (10), the liquid extraction pump (20) and the waste liquid storage tank (21) are connected in sequence through a pipeline.

2. The real-time detection device for the hydroxyl value of an acrylate monomer according to claim 1, characterized in that: The invention also comprises a control system (22); the first infusion pump (2), the lifting device (3), the test electrode (4), the second infusion pump (12), the third infusion pump (14), the fourth infusion pump (16), the fifth infusion pump (18), the liquid extraction pump (20) and each control valve are connected to the control system (22) and controlled by the control system (22).

3. The real-time detection device for the hydroxyl value of an acrylate monomer according to claim 2, characterized in that: The control system (22) is equipped with a status display and a parameter setting display.

4. The real-time detection device for the hydroxyl value of an acrylate monomer according to any one of claims 1 to 3, characterized in that: The first infusion pump (2), the second infusion pump (12), the third infusion pump (14), the fourth infusion pump (16) and the fifth infusion pump (18) are all constant-pressure infusion pumps; and the liquid extraction pump (20) is a constant-pressure liquid extraction pump (20).

5. The real-time detection device for the hydroxyl value of an acrylate monomer according to any one of claims 2 or 3, characterized in that: The lifting device (3) comprises a support frame, on which six independent lifting drive structures are arranged, and a test electrode (4), a sampling tube (5), a solvent dropping tube (6), a reaction reagent dropping tube (7), a titration liquid dropping tube (8), a distilled water dropping tube (9), and a waste liquid suction tube (10) are respectively connected to the six lifting drive structures, and each lifting drive structure is connected to a control system (22) and controlled by the control system (22).

6. The real-time detection device for the hydroxyl value of an acrylate monomer according to claim 5, characterized in that: The lifting drive structure is a track slider structure, the lifting drive structure includes a track and a slider, the track is vertically installed on the support frame, the slider is slidably matched on the track and moves up and down along the track under the control of the system control, the test electrode (4), the sampling tube (5), the solvent dripping tube (6), the reaction reagent dripping tube (7), the titration liquid dripping tube (8), the distilled water dripping tube (9) and the waste liquid suction tube (10) are respectively connected to the slider of the corresponding lifting drive structure and move up and down under the drive of the slider; or the lifting drive structure is a crawler structure, the crawler is vertically installed on the support frame and can reciprocate in both directions under the control of the system control, the test electrode (4), the sampling tube (5), the solvent dripping tube (6), the reaction reagent dripping tube (7), the titration liquid dripping tube (8), the distilled water dripping tube (9) and the waste liquid suction tube (10) are respectively connected to one side of the crawler of the corresponding lifting drive structure, and the crawler double The lifting drive structure is a foldable lifting frame structure, which is mounted on a support frame and can be extended and retracted under the control of the system control. The test electrode (4), the sampling tube (5), the solvent dropping tube (6), the reaction reagent dropping tube (7), the titration liquid dropping tube (8), the distilled water dropping tube (9) and the waste liquid suction tube (10) are respectively connected to the bottom of the foldable lifting frame corresponding to the lifting drive structure. The foldable lifting frame is extended and retracted, thereby driving the test electrode (4), the sampling tube (5), the solvent dropping tube (6), the reaction reagent dropping tube (7), the titration liquid dropping tube (8), the distilled water dropping tube (9) or the waste liquid suction tube (10) to move up and down.

7. The real-time detection device for the hydroxyl value of an acrylate monomer according to claim 5, characterized in that: The lifting device (3) also includes an XY moving mechanism, the top of the support frame is installed on the XY moving mechanism, and the XY moving mechanism is connected to the control system (22) and controlled by the control system (22).

8. The real-time detection device for the hydroxyl value of an acrylate monomer according to any one of claims 1 to 3, characterized in that: The sample plate (11) is provided with more than two positioning holes (111), the number of sample cups is more than two, the sample cups are placed in the positioning holes (111), and each positioning hole (111) has only one sample cup.

9. The real-time detection device for the hydroxyl value of an acrylate monomer according to any one of claims 1 to 3, characterized in that: A magnetic stirrer and a weighing sensor are provided at the bottom of each positioning hole (111), and a polytetrafluoroethylene type magnetic stirring rotor is provided in each sample cup.

10. The real-time detection device for the hydroxyl value of an acrylate monomer according to any one of claims 1 to 3, characterized in that: The materials used for the solvent storage tank (13), the reaction reagent storage tank (15), the titration liquid storage tank (17) and the distilled water storage tank (19) are all brown glass; the waste liquid storage tank (21) is provided with a liquid outlet at the bottom, and a control valve is provided on the liquid outlet.

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