Method and device for preparing clean high-grade fluororubber

Abstract

The invention discloses a method for preparing clean high-grade fluororubber. The method comprises the following steps of: 1, reacting vinylidene fluoride, hexafluoropropylene gas and an initiator to generate fluororubber latex; 2, carrying out condensation reaction on aluminum sulfate and fluororubber latex to obtain a primary finished product; and 3, finally, dehydrating and drying the granular fluororubber, so as to obtain the high-grade granular fluororubber. The invention further discloses a device for preparing the clean high-grade fluororubber, a raw material container (8) is communicated with a polymerization reaction kettle, and an auxiliary material container (11) is communicated with an input port II (10); the polymerization reaction kettle (2) is communicated with the coagulation reaction kettle (3), the coagulant preparation barrel (4) is communicated with the coagulation reaction kettle (3) through the coagulant pump (13), and the coagulation reaction kettle (3) is communicated with the fluororubber finished product storage tank (15) sequentially through the cleaning device (5), the filtering device (6) and the drying device (7). According to the fluororubber preparation device, the product performance of fluororubber is improved, and the environment can be effectively protected in the preparation process.

Description

Technical Field

[0001] The invention relates to the technical field of fluororubber preparation, and in particular to a method for preparing clean high-grade fluororubber and a preparation device thereof. Background Art

[0002] Fluororubber is widely used in aerospace, automobile manufacturing, petrochemical and other fields due to its excellent chemical resistance, high temperature resistance and oil resistance. In the preparation process of fluororubber, the coagulant has an important influence on the performance of the product. When preparing fluororubber now, all raw materials and coagulants are put together for preparation reaction. In this way, the coagulant can easily cause raw material pollution during the reaction and the prepared fluororubber has more impurities, and the performance of fluororubber is not good. Therefore, it is necessary to wash the prepared product many times during the whole preparation process. This not only causes a large number of washing times, a large workload, and a high preparation cost, but also causes an increase in the amount of sewage due to excessive washing times, which has a serious impact on the environment. Summary of the invention

[0003] The present invention provides a method for preparing clean high-grade fluororubber and a preparation device thereof. The method and the device can not only improve the product performance of the fluororubber, but also reduce the production cost and effectively protect the environment during the preparation.

[0004] The present invention adopts the following technical scheme: a method for preparing clean high-grade fluororubber, which comprises the following steps: Step 1: inputting vinylidene fluoride gas and hexafluoropropylene gas in the raw material container into a compressor for compression and then discharging them into a polymerization reactor, and at the same time discharging the initiator in the auxiliary material container into the polymerization reactor, and the vinylidene fluoride gas and hexafluoropropylene gas react with the initiator in the polymerization reactor to generate fluororubber latex; Step 2: storing a coagulant in a coagulant configuration cylinder and stirring the coagulant through a stirrer, wherein aluminum sulfate is used as the coagulant, and the concentration of aluminum sulfate is 5% to 25%. The aluminum sulfate is input into a coagulant reactor through a coagulant pump to react with fluororubber latex for coagulation, wherein the pH value during the coagulation reaction is 3 to 8, and the temperature during the coagulation reaction is 20° C. to 70° C., and a granular fluororubber primary product is obtained after the coagulation reaction, and sewage generated during the coagulation reaction is discharged from a sewage discharge port; Step three, put the granular fluororubber finished product into an ultrasonic cleaning machine for cleaning, clean the reaction residues on the surface, then screen the cleaned granular fluororubber through a particle filter screen, screen out the defective particles, and finally send the screened granular fluororubber to a vacuum drying oven for dehydration and drying to obtain high-grade granular fluororubber, and store the obtained high-grade granular fluororubber in a fluororubber finished product storage tank for storage.

[0005] Furthermore, the concentration of aluminum sulfate in step 2 of the present invention is 10% to 15%, the amount of aluminum sulfate added is 0.5% to 5% of the total mass of vinylidene fluoride gas, hexafluoropropylene gas and initiator, and the mass ratio of aluminum sulfate to fluororubber latex is 1:10.

[0006] Furthermore, the pH value during the condensation reaction in step 2 of the present invention is 6-7, and the temperature during the condensation reaction is 30°C-50°C.

[0007] Furthermore, in step 1 of the present invention, the initiator is an organic peroxide.

[0008] The present invention also discloses a device for preparing clean high-grade fluororubber, which includes a compressor, a polymerization reactor, a coagulant reactor, a coagulant configuration cylinder, a cleaning device, a filtering device and a drying device. The output port of the raw material container is connected to the input port I of the polymerization reactor through the compressor, and an input port II is also provided on the upper part of the polymerization reactor. The output port of the auxiliary material container is connected to the input port II, the output port at the bottom of the polymerization reactor is connected to the input port I on the upper part of the coagulant reactor, the output port of the coagulant configuration cylinder is connected to the input port II on the upper part of the coagulant reactor through a coagulant pump, an agitator is vertically installed in the coagulant configuration cylinder, and the output port at the bottom of the coagulant reactor is connected to the fluororubber finished product storage tank through the cleaning device, the filtering device and the drying device in sequence.

[0009] Furthermore, a sewage discharge port is provided on the top of the condensation reactor.

[0010] Furthermore, the cleaning device is configured as an ultrasonic cleaning machine.

[0011] Furthermore, the filtering device is configured as a particle filtering screen.

[0012] Furthermore, the drying device is configured as a vacuum drying oven.

[0013] Furthermore, the coagulant pump is a liquid metering pump.

[0014] The present invention has the following beneficial effects: after adopting the above technical scheme, in the process of preparing fluororubber, the present invention prepares fluororubber latex and coagulant separately, and then performs coagulation reaction, and the coagulant adopts aluminum sulfate, so that the other reactions that interfere with the preparation of fluororubber can be avoided during the coagulation reaction, and the preparation process is optimized. At the same time, high-quality fluororubber can be obtained through subsequent washing, filtering and drying, and the product performance of fluororubber is improved. The impurity content is also relatively low, and in the process of preparing fluororubber by using the method and device, fluororubber particles are prepared, and the reaction is relatively clean, so the number of washing times is also reduced in the preparation process, thereby reducing the discharge of sewage and effectively protecting the environment. The coagulant configuration cylinder of the present invention is vertically installed with an agitator, so that the coagulant participating in the coagulation reaction is more refined, the coagulation reaction is more sufficient, and the quality of the prepared fluororubber is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0017] The preferred embodiments of the present invention are described in detail below so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0018] The present invention discloses a method for preparing clean high-grade fluororubber, which comprises the following steps: Step 1: input the vinylidene fluoride gas and hexafluoropropylene gas in the raw material container 8 into the compressor 1 for compression and then discharge into the polymerization reactor 2, and at the same time, discharge the initiator in the auxiliary material container 11 into the polymerization reactor 2, and the vinylidene fluoride gas and hexafluoropropylene gas react with the initiator in the polymerization reactor 2 to generate fluororubber latex, and the initiator in step 1 is an organic peroxide; Step 2, a coagulant is placed in the coagulant configuration cylinder 4, and the coagulant is stirred by the stirrer 17. Aluminum sulfate is used as the coagulant, and the concentration of aluminum sulfate is 5% to 25%. Aluminum sulfate is input into the coagulant reactor 3 through the coagulant pump 13 to react with fluororubber latex for coagulation. The pH value during the coagulation reaction is 3 to 8, and the temperature during the coagulation reaction is 20°C to 70°C. After the coagulation reaction, a granular fluororubber primary product is obtained. During the coagulation reaction, sewage is generated and discharged from the sewage discharge port 16. In step 2, the concentration of aluminum sulfate is 10% to 15%, and the amount of aluminum sulfate added is 0.5% to 5% of the total mass of vinylidene fluoride gas, hexafluoropropylene gas and initiator, preferably 1% to 4%. The mass ratio of aluminum sulfate to fluororubber latex is 1:10. In step 2, the pH value during the coagulation reaction is 6 to 7, and the temperature during the coagulation reaction is 30°C to 50°C. Step three, put the granular fluororubber finished product into an ultrasonic cleaning machine for cleaning, clean the reaction residues on the surface, then screen the cleaned granular fluororubber through a particle filter screen, screen out the defective particles, and finally send the screened granular fluororubber to a vacuum drying oven for dehydration and drying to obtain high-grade granular fluororubber, and store the obtained high-grade granular fluororubber in a fluororubber finished product storage tank 15 for storage.

[0019] The technical solution of the present invention is further illustrated by examples below.

[0020] Embodiment 1, the present invention provides a method for preparing clean high-grade fluororubber, which comprises the following steps: step 1, inputting vinylidene fluoride gas and hexafluoropropylene gas in a raw material container 8 into a compressor 1 for compression and then discharging them into a polymerization reactor 2, and at the same time discharging an initiator in an auxiliary material container 11 into the polymerization reactor 2, and the vinylidene fluoride gas and the hexafluoropropylene gas react with the initiator in the polymerization reactor 2 to generate fluororubber latex, and the initiator of this embodiment adopts an organic peroxide; Step 2: placing a coagulant in the coagulant configuration cylinder 4 and stirring the coagulant by the stirrer 17; aluminum sulfate is used as the coagulant; the concentration of aluminum sulfate is 10%; the amount of aluminum sulfate added is 1% of the total mass of vinylidene fluoride gas, hexafluoropropylene gas and initiator; the mass ratio of aluminum sulfate to fluororubber latex is 1:10; aluminum sulfate is input into the coagulant reactor 3 through the coagulant pump 13 to react with the fluororubber latex; the pH value during the coagulant reaction is 6; the temperature during the coagulant reaction is 40° C.; a granular fluororubber primary product is obtained after the coagulant reaction; sewage generated during the coagulant reaction is discharged from the sewage outlet 16; Step three, put the granular fluororubber finished product into an ultrasonic cleaning machine for cleaning, clean the reaction residues on the surface, then screen the cleaned granular fluororubber through a particle filter screen, screen out the defective particles, and finally send the screened granular fluororubber to a vacuum drying oven for dehydration and drying to obtain high-grade granular fluororubber, and store the obtained high-grade granular fluororubber in a fluororubber finished product storage tank 15 for storage.

[0021] Embodiment 2, the present invention provides a method for preparing clean high-grade fluororubber, which comprises the following steps: step 1, inputting vinylidene fluoride gas and hexafluoropropylene gas in the raw material container 8 into the compressor 1 for compression and then discharging into the polymerization reactor 2, and at the same time discharging the initiator in the auxiliary material container 11 into the polymerization reactor 2, and the vinylidene fluoride gas and the hexafluoropropylene gas and the initiator react with each other in the polymerization reactor 2 to generate fluororubber latex, and the initiator of this embodiment adopts an organic peroxide; Step 2: placing a coagulant in the coagulant configuration cylinder 4 and stirring the coagulant by the stirrer 17; aluminum sulfate is used as the coagulant; the concentration of aluminum sulfate is 12%; the amount of aluminum sulfate added is 2% of the total mass of vinylidene fluoride gas, hexafluoropropylene gas and initiator; the mass ratio of aluminum sulfate to fluororubber latex is 1:10; aluminum sulfate is input into the coagulant reactor 3 through the coagulant pump 13 to react with the fluororubber latex; the pH value during the coagulant reaction is 6; the temperature during the coagulant reaction is 30° C.; after the coagulant reaction, a granular fluororubber primary product is obtained; sewage generated during the coagulant reaction is discharged from the sewage outlet 16; Step three, put the granular fluororubber finished product into an ultrasonic cleaning machine for cleaning, clean the reaction residues on the surface, then screen the cleaned granular fluororubber through a particle filter screen, screen out the defective particles, and finally send the screened granular fluororubber to a vacuum drying oven for dehydration and drying to obtain high-grade granular fluororubber, and store the obtained high-grade granular fluororubber in a fluororubber finished product storage tank 15 for storage.

[0022] Embodiment 3, the present invention provides a method for preparing clean high-grade fluororubber, which comprises the following steps: step 1, inputting vinylidene fluoride gas and hexafluoropropylene gas in the raw material container 8 into the compressor 1 for compression and then discharging into the polymerization reactor 2, and at the same time discharging the initiator in the auxiliary material container 11 into the polymerization reactor 2, and the vinylidene fluoride gas and the hexafluoropropylene gas and the initiator react with each other in the polymerization reactor 2 to generate fluororubber latex, and the initiator of this embodiment adopts an organic peroxide; Step 2: placing a coagulant in the coagulant configuration cylinder 4 and stirring the coagulant by the stirrer 17; aluminum sulfate is used as the coagulant; the concentration of aluminum sulfate is 15%; the amount of aluminum sulfate added is 4% of the total mass of vinylidene fluoride gas, hexafluoropropylene gas and initiator; the mass ratio of aluminum sulfate to fluororubber latex is 1:10; aluminum sulfate is input into the coagulant reactor 3 through the coagulant pump 13 to react with the fluororubber latex; the pH value during the coagulant reaction is 7; the temperature during the coagulant reaction is 50° C.; a granular fluororubber primary product is obtained after the coagulant reaction; sewage generated during the coagulant reaction is discharged from the sewage outlet 16; Step three, put the granular fluororubber finished product into an ultrasonic cleaning machine for cleaning, clean the reaction residues on the surface, then screen the cleaned granular fluororubber through a particle filter screen, screen out the defective particles, and finally send the screened granular fluororubber to a vacuum drying oven for dehydration and drying to obtain high-grade granular fluororubber, and store the obtained high-grade granular fluororubber in a fluororubber finished product storage tank 15 for storage.

[0023] exist Figure 1 The present invention provides a device for preparing clean high-grade fluororubber, which comprises a compressor 1, a polymerization reactor 2, a coagulation reactor 3, a coagulant configuration cylinder 4, a cleaning device 5, a filtering device 6 and a drying device 7. The output port of the raw material container 8 is connected to the input port Ⅰ9 of the polymerization reactor 2 through the compressor 1, and an input port Ⅱ10 is also provided on the upper part of the polymerization reactor 2. The output port of the auxiliary material container 11 is connected to the input port Ⅱ10, the output port at the bottom of the polymerization reactor 2 is connected to the input port Ⅰ12 on the upper part of the coagulation reactor 3, and the output port of the coagulant configuration cylinder 4 is connected to the input port Ⅰ13 of the polymerization reactor 2. The coagulant pump 13 is connected to the input port II 14 on the upper part of the coagulant reactor 3, and an agitator 17 is vertically installed in the coagulant configuration cylinder 4. The output port at the bottom of the coagulant reactor 3 is connected to the fluororubber finished product storage tank 15 through the cleaning device 5, the filtering device 6 and the drying device 7 in sequence. The top of the coagulant reactor 3 of this embodiment is provided with a sewage discharge port 16, the cleaning device 5 of this embodiment is configured as an ultrasonic cleaning machine, the filtering device 6 of this embodiment is configured as a particle filtering screen, and the drying device 7 of this embodiment is configured as a vacuum drying oven. The coagulant pump 13 of this embodiment adopts a liquid metering pump.

[0024] Without limitation to this, any changes or substitutions that are not conceived through creative work should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope defined in the claims.

Claims

1. A method for preparing clean high-grade fluororubber, characterized in that It includes the following steps: Step 1: inputting vinylidene fluoride gas and hexafluoropropylene gas in the raw material container (8) into the compressor (1) for compression and then discharging them into the polymerization reactor (2); at the same time, discharging the initiator in the auxiliary material container (11) into the polymerization reactor (2); the vinylidene fluoride gas and hexafluoropropylene gas react with the initiator in the polymerization reactor (2) to generate fluororubber latex; Step 2: a coagulant is placed in a coagulant preparation cylinder (4) and stirred by a stirrer (17). Aluminum sulfate is used as the coagulant and the concentration of the aluminum sulfate is 5% to 25%. The aluminum sulfate is input into a coagulant reaction kettle (3) through a coagulant pump (13) to react with the fluororubber latex for coagulation. The pH value during the coagulation reaction is 3 to 8 and the temperature during the coagulation reaction is 20° C. to 70° C. After the coagulation reaction, a granular fluororubber primary product is obtained. Wastewater generated during the coagulation reaction is discharged from a wastewater discharge port (16); Step three, the granular fluororubber finished product is placed in an ultrasonic cleaning machine for cleaning to clean the reaction residues on the surface, and then the cleaned granular fluororubber is screened through a particle filter screen to remove the defective particles, and finally the screened granular fluororubber is sent to a vacuum drying oven for dehydration and drying to obtain high-grade granular fluororubber, and the obtained high-grade granular fluororubber is stored in a fluororubber finished product storage tank (15) for storage.

2. The method for preparing clean high-grade fluororubber according to claim 1, characterized in that In step 2, the concentration of aluminum sulfate is 10% to 15%, the amount of aluminum sulfate added is 0.5% to 5% of the total mass of vinylidene fluoride gas, hexafluoropropylene gas and initiator, and the mass ratio of aluminum sulfate to fluororubber latex is 1:

10.

3. The method for preparing clean high-grade fluororubber according to claim 1, characterized in that The pH value during the condensation reaction in step 2 is 6-7, and the temperature during the condensation reaction is 30°C-50°C.

4. The method for preparing clean high-grade fluororubber according to claim 1, characterized in that In step 1, the initiator is an organic peroxide.

5. A device for preparing clean high-grade fluororubber, characterized in that The invention comprises a compressor (1), a polymerization reactor (2), a coagulation reactor (3), a coagulant configuration cylinder (4), a cleaning device (5), a filtering device (6) and a drying device (7). The output port of the raw material container (8) is connected to the input port I (9) of the polymerization reactor (2) through the compressor (1). An input port II (10) is also provided on the upper part of the polymerization reactor (2). The output port of the auxiliary material container (11) is connected to the input port II (10). The output port at the bottom of the polymerization reactor (2) is connected to the input port I (12) on the upper part of the coagulation reactor (3). The output port of the coagulant configuration cylinder (4) is connected to the input port II (14) on the upper part of the coagulation reactor (3) through a coagulant pump (13). A stirrer (17) is vertically installed in the coagulant configuration cylinder (4). The output port at the bottom of the coagulation reactor (3) is connected to the fluororubber finished product storage tank (15) through the cleaning device (5), the filtering device (6) and the drying device (7) in sequence.

6. The device for preparing clean high-grade fluororubber according to claim 1, characterized in that The top of the condensation reactor (3) is provided with a sewage discharge port (16).

7. The device for preparing clean high-grade fluororubber according to claim 1, characterized in that The cleaning device (5) is configured as an ultrasonic cleaning machine.

8. The device for preparing clean high-grade fluororubber according to claim 1, characterized in that The filtering device (6) is configured as a particle filtering screen.

9. The device for preparing clean high-grade fluororubber according to claim 1, characterized in that The drying device (7) is configured as a vacuum drying oven.

10. The device for preparing clean high-grade fluororubber according to claim 1, characterized in that The coagulant pump (13) is a liquid metering pump.

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