Device for measuring hydroxyl value of polyether polyol

Abstract

The utility model discloses a device for measuring the hydroxyl value of polyether polyol, and belongs to the technical field of chemical analysis. The device comprises an oil bath pan, wherein the oil bath pan is provided with an ultrasonic device, an electric heating device, an air cooling device, a lifting device, a rotating device and a sample holder; the sample rack is used for placing a test bottle and comprises a fixed rack body, a rotating rack body and a rotating shaft, and the rotating rack body is rotatably arranged above the fixed rack body through the rotating shaft; the lifting device is used for driving the sample rack to do lifting motion in the oil bath pan; the rotating device is used for driving the rotating frame body to axially rotate on the fixed frame body; the electric heating device is used for heating conduction oil in the oil bath pan; the ultrasonic device is used for ultrasonically dispersing a sample in the test bottle; the air cooling device is used for cooling the sample in the sample bottle. By using the device, the detection process time can be effectively shortened, and the detection efficiency is improved; manual operation errors can be reduced, and the detection precision is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to chemical analysis technical field, concretely relates to a device for determining polyether polyol hydroxyl value. BACKGROUND

[0002] Hydroxyl value is an important characteristic index of polyether polyol, it relates to the content of functional group in polyether and the molecular weight of polyether, is the important index in the process of polyether production, application, research and development, in polyether polyol synthesis industry, hydroxyl value is also used to control process production, so that the like feeding amount, error analysis, output estimation cannot leave hydroxyl value.

[0003] The determination method of hydroxyl value includes potentiometric titration and colorimetric titration, wherein, the colorimetric titration adopts the method recorded in GB / T12008.3-2009 plastics polyether polyol third part: determination of hydroxyl value, which includes the following steps: taking sample to the conical flask, recording the quality of test material;Accurately move 25ml phthalic anhydride acylation reagent to each test material and blank conical flask, the phthalic anhydride acylation reagent used is added with imidazole, shake the bottle until the test material is dissolved, connect the air condenser to each conical flask, put it in (115±2) ℃ oil bath for 30min;After heating, take the device out of the oil bath and cool to room temperature, wash the condenser with 30ml pyridine and remove the condenser;Quantitatively transfer the solution to 250ml beaker, wash the conical flask with 20ml pyridine;Finally, the consumption of sodium hydroxide standard titration solution is determined by using potentiometric titration or colorimetric titration, and the hydroxyl value is calculated.

[0004] The existing determination method of hydroxyl value has the following problems in determination:

[0005] I. The acylation reagent is manually added by using a pipette, which requires high operation and is easy to produce errors.

[0006] II. Some high viscosity samples are difficult to dissolve by shaking the conical flask, and need to be heated and stirred before completely dissolving, which is time-consuming and inconvenient to operate.

[0007] III. The sample is naturally cooled for a long time.

[0008] IV. After the sample bottle is taken out of the oil bath, the outer wall is stained with oil stains, which is easy to drop and contaminate. UTILITY MODEL CONTENT

[0009] To solve the above problems, the utility model provides a device for determining polyether polyol hydroxyl value.

[0010] The technical scheme adopted by the utility model is:

[0011] The utility model provides a device for determining polyether polyol hydroxyl value, including oil bath pot, oil bath pot is equipped with ultrasonic device, electric heating device, air -cooled device, lifting device, rotating device and sample holder, the sample holder is used for placing test bottle, including fixed frame body, rotating frame body and pivot, rotating frame body is rotatable and is established in the top of fixed frame body through pivot, and a plurality of through -holes for inserting test bottle are evenly set up on rotating frame body, the lifting device is used for driving the sample holder does lifting motion in oil bath pot, the rotating device is used for driving rotating frame body rotates on the fixed frame body axial, the electric heating device is used for heating the heat conducting oil in oil bath pot, the ultrasonic device is used for ultrasonic dispersion sample in test bottle, the air -cooled device is used for cooling sample in test bottle.

[0012] By setting up ultrasonic device, high viscosity sample can be completely dissolved in acylation reagent in short time, reduce the workload of operator, improve the analysis efficiency. Set up air -cooled device and lifting device, after the reaction is completed, the sample holder is driven to rise by lifting device, and separates from heat conducting oil, at this time, air -cooled device is opened, and the sample can be cooled quickly, and the analysis efficiency is improved. In the cooling process, the rotating device can be driven to rotate the rotating frame body, and the cooling efficiency is further improved.

[0013] Further, it further includes the dosing system set up in one side of oil bath pot, the dosing system includes the reagent bottle for containing acylation reagent, piston dosing pump, dosing pipe and controller, and the piston dosing pump is connected with reagent bottle and test bottle through dosing pipe, and the piston dosing pump is connected with controller through wire, and the controller is used to control the piston dosing pump and quantitatively add acylation reagent to test bottle.

[0014] By setting up dosing system and controller, when the opening of test bottle on rotating frame body is directly opposite the outlet of dosing pipe through the rotation of rotating device, the controller controls the dosing system and quantitatively adds acylation reagent to test bottle, so as to accurately control the addition amount of acylation reagent and reduce the human operation error.

[0015] Further, the ultrasonic device, electric heating device, air -cooled device, lifting device and rotating device are connected with controller through wire respectively. The controller can automatically control the start and stop of the above device, control ultrasonic time, heating time, air -cooled time, automatically control the lifting position of sample holder and the rotation direction of rotating frame body, so as to improve the analysis efficiency and ensure the analysis accuracy.

[0016] Further, the oil bath pot is provided with a temperature sensor for measuring the temperature of the heat-conducting oil, the temperature sensor is connected to the controller through a wire; the upper portion of the oil bath pot is provided with a position sensor for detecting the rotating position of the test bottle, the position sensor is connected to the controller through a wire.

[0017] Further, the oil bath pot is provided with a temperature sensor for measuring the temperature of the heat-conducting oil, the temperature sensor is connected to the controller through a wire; the upper portion of the oil bath pot is provided with a position sensor for detecting the rotating position of the test bottle, the position sensor is connected to the controller through a wire.

[0018] By arranging the automatic potentiometric titrator, the analysis efficiency and accuracy can be improved; and by extending one end of the titration table of the automatic potentiometric titrator to the upper portion of the oil bath pot, the oil stains on the outer wall of the sample bottle taken out from the oil bath pot can be returned to the oil bath pot from the titration table, so that the environmental pollution is reduced.

[0019] Further, the oil bath pot is provided with a temperature sensor for measuring the temperature of the heat-conducting oil, the temperature sensor is connected to the controller through a wire; the upper portion of the oil bath pot is provided with a position sensor for detecting the rotating position of the test bottle, the position sensor is connected to the controller through a wire.

[0020] Further, the electric heating device is a heating ring, and the heating ring is fixed to the bottom of the oil bath pot.

[0021] Further, the air cooling device is a fan, and the fan is fixed to the side wall of the oil bath pot through a support.

[0022] Further, the lifting device is a lead screw lifter, and the lead screw lifter is fixedly installed at the central position of the bottom of the oil bath pot, and a lifting table of the lead screw lifter is fixedly connected to the fixed frame body.

[0023] Further, the rotating shaft is fixedly sleeved with a driven gear, a motor is fixedly installed on the fixed frame body, a driving gear is fixedly connected to the output shaft of the motor, and the driving gear is engaged with the driven gear; the motor, the driving gear and the driven gear constitute the rotating device.

[0024] The device can effectively shorten the detection time, improve the detection efficiency, reduce the human operation error and improve the detection accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state.

[0026] Figure 2 The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state.

[0027] Figure 3 The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state.

[0028] Figure 4 The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state.

[0029] Figure 5 The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state.

[0030] Figure 6 The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state.

[0031] Figure 7 The structure schematic diagram of the device for measuring the hydroxyl value of polyether polyol under oil bath state. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical scheme and advantages of the utility model more clear, the following will combine with the drawings and a preferred embodiment to make clear, complete description to the technical scheme of the utility model.

[0033] Example 1

[0034] Referring to Figures 1-7 The device for measuring the hydroxyl value of polyether polyol comprises an oil bath pot 10, an electric heating device 11 arranged on the water bath pot, a forced air cooling device 12, a lifting device 13, a rotating device 14 and a sample holder 15, a dosing system 20 arranged on one side of the oil bath pot and an automatic potentiometric titrator 30 arranged on the other side of the oil bath pot.

[0035] In the embodiment, the oil bath pot 10 uses an existing ultrasonic water bath pot, and the conductive oil is added in the water bath pot during use. The bottom of the water bath pot is detachably fixed with an electric heating coil, i.e., the heating device 11. A fan, i.e., the air cooling device 12, a position sensor 4 and a temperature sensor 5 are fixed on the side wall of the water bath pot through supports, respectively. The fan is located above the water bath pot and the air outlet is directed to the sample holder 15 in the air cooling state. The position sensor 4 is close to the dosing system 20 and is located directly below the sampling pipeline. The temperature sensor 5 is vertically arranged and the working end is inserted into the conductive oil.

[0036] A lifting device 13 is detachably installed at the center position of the electric heating coil at the bottom of the water bath pot. In the embodiment, the lifting device 13 uses an existing screw rod lifter. The base of the screw rod lifter is fixed on the bottom of the water bath pot through screws. The lifting screw rod extends vertically upward to connect a lifting platform. The rotating device 14 and the sample holder 15 are installed on the lifting platform.

[0037] The sample holder 15 includes a fixed frame body 152, a rotating frame body 151 and a rotating shaft 153. The rotating frame body 151 is rotatably arranged above the fixed frame body 152 through the rotating shaft 153. Eight through holes 1515 for inserting test bottles are uniformly arranged on the rotating frame body 151 in the circumferential direction. The rotating ring 1525 for supporting the test bottles is rotatably arranged on the fixed frame body 151 corresponding to the through holes 1515.

[0038] In specific implementation, the fixed frame body 152 includes a center fixed part 1523, an annular fixed part 1521 and a rib part 1522 connecting the center fixed part 1523 and the annular fixed part 1521. The number of the rib part 1522 is 3-5. The gap between the adjacent two rib parts 1522 can reduce the resistance during lifting movement. The upper side of the center fixed part 1523 is provided with an annular groove 1525. The rotating ring 1525 is rotatably arranged in the annular groove 1525. The rotating ring 1525 can be a flat ring or can be provided with two side walls. In order to reduce the rotating friction, a plurality of rotating balls can be arranged in the annular groove 1525, so that the rotating ring 1525 is rotatably connected with the annular groove 1525 through the rotating balls. The bearing hole 1524 is arranged at the center position of the center fixed part 1523. The bearing hole 1524 is provided with a bearing, so that the lower end of the rotating shaft 153 is rotatably connected with the fixed frame body 152 by inserting into the inner ring of the bearing. Six screw holes 1524 are arranged at the outer edge of the center fixed part 1523.

[0039] The rotating frame 151 comprises a central rotating part 1513, an annular rotating part 1511 and a plurality of rib parts 1512 connecting the central rotating part 1513 and the annular rotating part 1511, the number of the rib parts 1512 is 3-5, and the space between two adjacent rib parts 1512 is formed to reduce the resistance during the lifting movement. A hole 1514 for fixing the rotating shaft 153 is formed in the center of the central rotating part 1513; and eight through holes 1515 for inserting the test bottles are formed in the annular rotating part 1511.

[0040] The outer circle diameter of the fixed frame 152 is equal to that of the rotating frame 151, and the fixed frame 152 is coaxially arranged above the rotating frame 151. The fixed frame 152 is fixed on the lifting platform of the lifting device through the screw passing through the screw hole 1524 in the center of the fixed frame 152, the rotating frame 151 is rotatably arranged above the fixed frame 152 through the rotating shaft 153, the passive gear 143 is fixedly sleeved on the rotating shaft 153, the motor 141 is fixedly installed on the fixed frame 152, the driving gear 142 is fixedly connected with the output shaft of the motor 141, and the driving gear 142 is engaged with the passive gear 143; the motor, the driving gear and the passive gear form the rotating device 14. The motor 141 is a high-temperature-resistant servo motor.

[0041] In another embodiment of the utility model, the rotating device 14 can also comprise a motor and a pair of gear couplings, the motor is arranged above the oil bath pot through a support, the motor shaft vertically extends upwards to connect the gear coupling A, the upper end of the rotating shaft 153 extends out of the rotating frame 151 to connect the gear coupling B, when the sample frame 15 is lifted to the sample feeding state or the air cooling state, the gear coupling B and the gear coupling A are engaged, and the motor can drive the rotating shaft 153 to rotate; when the sample frame 15 is lowered, the gear coupling B and the gear coupling A are separated. The advantage of this design is that the motor can be selected as a common servo motor, thereby reducing the cost.

[0042] In the embodiment, the dosing system 20 comprises a reagent bottle 21 for containing acylation reagent, a piston dosing pump 23, a dosing pipe 22 and a controller 6, the reagent bottle 21 is arranged on the workbench plate 3 through a support, the piston dosing pump 22 is arranged above the reagent bottle, the inlet is connected with the reagent bottle through a suction pipe, the outlet is connected with the test bottle 1 through the dosing pipe 22, the piston dosing pump 23 is connected with the controller 6 through wires, and the controller 6 is used for controlling the piston dosing pump 23 to quantitatively add the acylation reagent into the test bottle 1. The piston dosing pump 22 is a prior art, and the reagent can be accurately injected into the test bottle by setting the volume flow in the controller.

[0043] In order to further improve the analysis efficiency and the analysis accuracy, the ultrasonic device of the ultrasonic water bath pot, the electric heating ring, the fan, the motor of the screw lifting machine, the motor 141 of the rotating device 14, the position sensor 4 and the temperature sensor 5 are respectively connected with the controller 6 through wires.

[0044] The starting and stopping of the above device is automatically controlled by the controller 6, so as to control the ultrasonic time, heating time, air cooling time, the lifting position of the sample holder and the rotating direction of the rotating body. The above control method is the prior art, and will not be described here.

[0045] In order to facilitate operation, a control panel can also be arranged on the outer wall of the ultrasonic water bath, and the control panel is provided with start-stop buttons of the ultrasonic device, the electric heating ring, the fan, the screw lifting machine, the motor 141 and the piston dosing pump 23.

[0046] In the embodiment, the automatic potentiometric titrator 30 is fixedly arranged on the workbench plate 3 through the support 3, one end of the titration table 31 of the automatic potentiometric titrator 30 is fixed on the support 3, and the other end extends to the upper side of the oil bath. In order to better recover the oil stains on the titration table, it is preferred that an oil dripping hole is arranged at the end of the oil bath.

[0047] The use method of the device in the embodiment includes the following steps:

[0048] In the initial state, the sample holder is lifted to the upper side of the oil bath, that is, the sample holder is in the sample feeding state.

[0049] A in the sample feeding state, the polyether polyol sample to be determined is weighed with six test bottles respectively, the sample mass is recorded as m1, and then the test bottles are placed on the sample holder of the oil bath;

[0050] B another empty test bottle is also placed on the sample holder of the oil bath;

[0051] C the rotating device is started, so that all the test bottles on the sample holder are rotated to the lower side of the sampling pipeline in turn, in the process, the piston dosing pump 23 and the motor 141 are controlled by the controller 6 to quantitatively inject 25ml of phthalic anhydride acylation reagent into each test bottle, after the completion of the above operation, the lifting device is started, so that the sample holder is lowered and all the test bottles are immersed in the heat-conducting oil;

[0052] For example, the rotating body 151 drives the reagent bottle to rotate, when a certain reagent bottle rotates to the lower side of the outlet of the dosing pipe 22, the position sensor 4 detects the position of the reagent bottle and transmits a signal to the controller, the controller controls the motor 141 to stop rotating, and the piston dosing pump 23 is started to quantitatively inject 25ml of phthalic anhydride acylation reagent into the corresponding test bottle; after the injection is completed, the controller controls the motor 141 to rotate again, and the above operation is repeated, that is, phthalic anhydride acylation reagent can be quantitatively injected into each test bottle.

[0053] D the ultrasonic device is started, and ultrasonic dispersion is performed for 1-5min, so that all the samples are completely dissolved in the acylation reagent;

[0054] EPut the test bottle cap on, connect the air condenser, start the heating device, heat the heat conducting oil to 115±2℃, and keep for 30 min;

[0055] FAfter the reaction is completed, start the lifting device again to lift the sample holder above the oil bath, then start the air cooling device to quickly cool the sample to room temperature, use a titration pipette to rinse the condenser with 10-30 mL of pyridine, and remove the condenser;

[0056] GTurn the sample holder, take out the test bottle, and place it on the operation platform of the automatic potentiometric titration device, titrate the hydroxyl value content with a standard hydrochloric acid solution with a concentration of cmol / L, record the volume of the standard hydrochloric acid solution used to titrate the blank sample as V0, and record the volume of the standard hydrochloric acid solution used to titrate the sample as V1, and titrate the hydroxyl value;

[0057] HCalculate the hydroxyl value OHV, expressed in grams of potassium hydroxide consumed per liter of sample, according to formula (1):

[0058]

[0059] In the formula:

[0060] V1- the volume of the standard sodium hydroxide titration solution consumed for titrating the sample, in milliliters (mL);

[0061] V0- the volume of the standard sodium hydroxide titration solution consumed for titrating the blank, in milliliters (mL);

[0062] c- the concentration of the standard sodium hydroxide titration solution for measuring the alkalinity, in moles per liter (mol / L);

[0063] m1- the mass of the sample, in grams (g).

[0064] Table 1 Comparison of polyether polyol hydroxyl value test results

[0065]

[0066] As can be seen from Table 1, the hydroxyl value of the polyether polyol tested using the device of the present application has a relative deviation of less than 1.2% compared with the result of the national standard test method, and the result is reliable.

[0067] The above description is only a preferred embodiment of the present application, and it should be noted that for ordinary skilled persons in the technical field, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements are also within the protection scope of the present application.

Claims

1. A device for measuring the hydroxyl value of polyether polyol, comprising an oil bath (10), characterized in that: The oil bath is provided with an ultrasonic device, an electric heating device (11), an air cooling device (12), a lifting device (13), a rotating device (14) and a sample rack (15); The sample rack (15) is used to place the test bottle (1), and includes a fixed frame (152), a rotating frame (151) and a rotating shaft (153). The rotating frame (151) is rotatable via the rotating shaft (153) and is arranged above the fixed frame (152). The rotating frame (151) is evenly provided with a plurality of through holes (1515) for inserting the test bottle. The lifting device (13) is used to drive the sample holder (15) to perform lifting motion in the oil bath (10); The rotating device (14) is used to drive the rotating frame (151) to rotate axially on the fixed frame (152); The electric heating device (11) is used to heat the heat-conducting oil in the oil bath pot (10); The ultrasonic device is used to ultrasonically disperse the sample in the test bottle (1); The air cooling device (12) is used to cool the sample in the sample bottle (1).

2. A device for measuring the hydroxyl value of polyether polyol according to claim 1, characterized in that, The invention also includes a dosing system (20) arranged on one side of the oil bath pot, wherein the dosing system (20) includes a reagent bottle (21) for containing an acylating agent, a piston dosing pump (23), a dosing pipe (22) and a controller (6). The piston dosing pump (23) is connected to the reagent bottle (21) and the test bottle (1) through the dosing pipe (22). The piston dosing pump (23) is connected to the controller (6) through a wire. The controller (6) is used to control the piston dosing pump (23) to quantitatively add the acylating agent to the test bottle (1).

3. A device for measuring the hydroxyl value of polyether polyol according to claim 2, characterized in that, The ultrasonic device, the electric heating device (11), the air cooling device (12), the lifting device (13) and the rotating device (14) are respectively connected to the controller (6) through wires.

4. A device for measuring the hydroxyl value of polyether polyol according to claim 3, characterized in that, A temperature sensor (5) for measuring the temperature of the heat-conducting oil is provided in the oil bath pot (10), and the temperature sensor (5) is connected to a controller via a wire; a position sensor (6) for detecting the rotation position of the test bottle is provided above the oil bath pot, and the position sensor (6) is connected to the controller (6) via a wire.

5. A device for measuring the hydroxyl value of polyether polyol according to claim 2, characterized in that, The invention also comprises an automatic potentiometric titrator (30) arranged on the other side of the oil bath pot (10), wherein the titration platform (31) electrode of the automatic potentiometric titrator is located above the side of the oil bath pot (10).

6. The device for measuring the hydroxyl value of polyether polyol according to claim 1, characterized in that: The oil bath (10) is an ultrasonic oil bath.

7. The device for measuring the hydroxyl value of polyether polyol according to claim 1, characterized in that: The electric heating device (11) is a heating coil, which is fixed to the bottom of the oil bath pot (10).

8. The device for measuring the hydroxyl value of polyether polyol according to claim 1, characterized in that: The air cooling device (12) is a fan, and the fan is fixed on the side wall of the oil bath pot (10) through a bracket.

9. The device for measuring the hydroxyl value of polyether polyol according to claim 1, characterized in that: The lifting device (13) is a screw lift, which is fixedly installed at the center of the bottom of the oil bath pot, and its lifting platform is fixedly connected to the fixed frame (152).

10. The device for measuring the hydroxyl value of polyether polyol according to claim 1, characterized in that: A passive gear (143) is fixedly mounted on the rotating shaft (153), a motor (141) is fixedly mounted on the fixed frame (152), a driving gear (142) is fixedly connected to the motor output shaft, and the driving gear (142) is meshed with the passive gear (143); the motor (141), the driving gear (142) and the passive gear (143) constitute the rotating device (14).

Images