CN115873162A - Preparation device and preparation method of oligomeric fluoroether peroxide for fluororubber - Google Patents

Abstract

The invention provides a device and a method for preparing oligomeric fluoroether peroxide for fluororubber, which can adopt a fluoroolefin monomer, oxygen and a molecular weight regulator to prepare fluoroether oligomer through oxidative polymerization by a low-temperature ultraviolet irradiation or irradiation method to obtain oligomeric fluoroether peroxide.

Description

A kind of preparation device and preparation method of oligofluoroether peroxide for fluororubber

technical field

The invention belongs to the technical field of organic fluorine chemistry, and in particular relates to a preparation device and a preparation method of oligofluoroether peroxide for fluorine rubber.

Background technique

The existing patent CN105111352A discloses a preparation method of a special fluoroether oligomer, which uses fluorine-containing olefin monomers, oxygen, and molecular weight modifiers to prepare fluoroether oligomers by oxidative polymerization through low-temperature ultraviolet light or irradiation methods. In addition to being used as a substitute for perfluorooctanoic acid, it can also be used as a key raw material for fluoroether oil and low-temperature resistant fluororubber; however, in the process of synthesizing the fluoroether oligomer, the ether bond prepared by this method and equipment is easy Docking forms a peroxygen bond. Since the temperature has a great influence on the peroxygen bond, too high or too low temperature will cause very unstable effects on the prepared product.

Contents of the invention

The invention provides a preparation device and method for oligofluoroether peroxide used in fluororubber, which not only adopts a simple preparation method and equipment, but also prepares fluoroether oligomers and oligofluoroether peroxides with stable properties. oxide.

The present invention adopts following technical scheme: a kind of preparation method of fluororubber oligofluoroether peroxide, it comprises the following steps:

Step 1: Mix high-purity oxygen and gas-phase telogen in a certain ratio and pass it into the liquid-phase photo-oxidation kettle of fluorine-containing olefins at a certain speed. The liquid-phase photo-oxidation kettle uses nitrogen to exhaust oxygen and dehumidify. Under the action of pressure, under the stirring of the mixer I, the fluorine-containing olefin is converted into a mixed product of perfluoropolyether-based peroxyacyl fluoride and perfluoropolyether acyl fluoride after being irradiated by ultraviolet light emitted by an ultraviolet lamp for a period of time;

In step 2, the mixture produced in step 1 is evaporated by the evaporator at 210°C and discharged into the fluorination reaction kettle, and then the fluorine gas diluted with nitrogen gas is introduced, and the acyl fluoride is removed after stirring to generate the fluorination reaction to form Stable end group;

Step 3, finally pass it into a vacuum rectification tower to separate different fractions of perfluoropolyether-based peroxides and perfluoropolyethers through vacuum distillation.

Further, the mixing volume ratio of high-purity oxygen and gas-phase telogen in step 1 of the present invention is 1:10-10:1, and the gas-phase telogen is 1-fluoro-1-chloroethylene (CH2=CFCL), One or more mixtures of chlorotrifluoroethylene (CF2=CFCL)2, 2-chloro-1,1-difluoroethylene (CF2=CHCL), trifluorochloromethane, trifluorobromomethane, trifluoroiodomethane, in In step 1, the temperature is -90-0°C, the pressure is 0.1-0.3MPa, the wavelength of the ultraviolet light is 200-400nm, the stirring speed of the mixer I is 50-500rpm, and the reaction time is 1-8h.

Further, the fluorine-containing olefins of the present invention are octafluoro-2-butene (cis or trans CF3CF=CFCF3), octafluoro-1-butene (CF3CF2CF=CF2), hexafluoropropylene (CF3CF=CF2), all One or more mixtures of fluoroisobutene (CF2=C(CF3)2), tetrafluoroethylene (CF2=CF2), hexafluorocyclobutene (C4F6).

Further, in the fluorine gas diluted with nitrogen gas in Step 2 of the present invention, nitrogen: fluorine = 1:10-10:1.

Further, the temperature of the overhead fraction of the vacuum rectification tower in Step 3 of the present invention is 35-90°C, the temperature of the bottom of the tower is 35-90°C, and the mass fraction of the perfluoropolyether-based peroxide in the mixed product is 10%-50% .

The invention also discloses a preparation device for oligofluoroether peroxide for fluororubber, which mainly includes a liquid phase photooxidation kettle, an evaporator, a fluorination reaction kettle, a vacuum rectification tower, and a liquid phase photooxidation kettle The feed inlet is located on the upper part of the kettle body, the outlet of the liquid phase photooxidation kettle is located at the bottom of the kettle body, the outlet of the liquid phase photooxidation kettle is connected with the top inlet of the evaporator, and the bottom outlet of the evaporator is connected with the fluorination The feed inlet at the top of the reaction kettle is connected, the outlet at the bottom of the fluorination reaction kettle is connected with the inlet at the bottom of the vacuum distillation tower, the top of the vacuum distillation tower is provided with a rectification product outlet, and the vacuum distillation tower There is also a heavy component outlet at the bottom of the tower.

Further, the liquid-phase photooxidation tank is equipped with a stirrer I and an ultraviolet lamp, and the stirrer I is located in the liquid-phase photo-oxidation tank opposite to the ultraviolet lamp.

Furthermore, the top of the evaporator is provided with a fluorine-containing olefin outlet, and the fluorine-containing olefin outlet recovers the incompletely converted fluorine-containing olefin.

Furthermore, the top of the fluorination reaction kettle is also equipped with a gas inlet, and the fluorine gas diluted with nitrogen enters the fluorination reaction kettle through the gas inlet, and the agitator II is arranged in the fluorination reaction kettle.

Further, the vacuum rectification tower is set as a gap vacuum rectification tower.

The present invention has the following beneficial effects: after adopting the above technical scheme, the method and device of the present invention can use fluorine-containing olefin monomers, oxygen, and molecular weight modifiers to prepare fluoroether low polymers to obtain oligofluoroether peroxides, the method not only has a simple and reliable preparation process, but also can prepare fluoroether oligomers and oligofluoroether peroxides with stable properties.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments of the present invention. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention , for those skilled in the art, other drawings can also be obtained according to the content of the embodiment of the present invention and these drawings without any creative effort.

Fig. 1 is a structural schematic diagram of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, only some structures related to the present invention are shown in the drawings but not all structures.

The invention discloses a preparation method of oligofluoroether peroxide for fluororubber, which comprises the following steps:

Step 1, high-purity oxygen and gas-phase telogen are mixed in a certain ratio and passed into the liquid-phase photo-oxidation kettle 1 of fluorine-containing olefins at a certain speed. The liquid-phase photo-oxidation kettle 1 uses nitrogen to exhaust oxygen and dehumidify. Under the action of temperature and pressure, under the agitation of the mixer I7, after a period of time of reaction by the ultraviolet light emitted by the ultraviolet lamp 8, the fluorine-containing olefin is converted into a mixture of perfluoropolyether-based peroxyacyl fluoride and perfluoropolyether acyl fluoride The product, the mixing volume ratio of high-purity oxygen and gas-phase telogen in step 1 is 1:10-10:1, the mixing volume ratio of high-purity oxygen and gas-phase telogen in this embodiment is 1:2, and the gas-phase telogen is 1-fluoro-1-chloroethylene (CH2=CFCL), chlorotrifluoroethylene (CF2=CFCL)2, 2-chloro-1,1-difluoroethylene (CF2=CHCL), trifluorochloromethane, trifluorobromomethane 1. One or more mixtures of iodotrifluoromethane. The gas phase telogen of this embodiment is chlorotrifluoromethane. In step 1, the temperature is -90-0°C and the pressure is 0.1-0.3MPa. The ultraviolet light The wavelength of 8 is 200-400nm, the stirring speed of mixer I7 is 50-500rpm, and the reaction time is 1-8h. In the present embodiment, the temperature in step 1 is -57--70°C, and the pressure is 0.1MPa. The wavelength of light 8 is 200nm, the stirring speed of mixer I7 is 100rpm, the reaction time is 5h, and the fluorine-containing olefins are octafluoro-2-butene (cis or trans CF3CF=CFCF3), octafluoro-1-butene ( One or more of CF3CF2CF=CF2), hexafluoropropylene (CF3CF=CF2), perfluoroisobutylene (CF2=C(CF3)2), tetrafluoroethylene (CF2=CF2), hexafluorocyclobutene (C4F6) Mixing, the fluorine-containing olefin in this embodiment is a mixture of hexafluoropropylene and tetrafluoroethylene, wherein hexafluoropropylene accounts for 80%, and tetrafluoroethylene accounts for 20%;

Step 2, the mixture produced in step 1 is evaporated by the evaporator 2 at 210°C and then discharged into the fluorination reaction kettle 3, and then the fluorine gas diluted with nitrogen gas is introduced, and the acyl fluoride is removed after stirring to generate a fluorination reaction , forming a stable end group, step 2 nitrogen in the fluorine diluted with nitrogen: fluorine = 1:10-10:1;

Step 3, finally pass into the vacuum rectification tower 4 and separate the perfluoropolyether-based peroxide and perfluoropolyether of different fractions through vacuum distillation, the mixed product perfluoropolyether described in step 3 Based on the peroxide mass fraction of 10%-50%, the temperature of the overhead fraction of the vacuum rectification tower 4 in this embodiment is 90°C, and the temperature at the bottom of the tower is 90°C.

In Fig. 1, the present invention also discloses a preparation device for oligofluoroether peroxide for fluororubber, which mainly includes a liquid phase photooxidation kettle 1, an evaporator 2, a fluorination reaction kettle 3 and vacuum distillation Tower 4, the feed port of the liquid-phase photooxidation kettle 1 is located at the top of the kettle body, the discharge port of the liquid-phase photooxidation kettle 1 is located at the bottom of the kettle body, and the discharge port of the liquid-phase photooxidation kettle 1 is connected to the bottom of the evaporator 2 The top inlet is connected, the bottom outlet of the evaporator 2 is connected with the top feed port of the fluorination reactor 3, and the bottom outlet of the fluorination reactor 3 is connected with the inlet at the bottom of the vacuum rectification tower 4, and the decompression The top of the rectification tower 4 is provided with a rectification product outlet 5, and the bottom of the vacuum rectification tower 4 is also provided with a heavy component outlet 6. The liquid phase photooxidation kettle 1 of the present embodiment is provided with a stirrer I7 and an ultraviolet lamp 8, Stirrer I7 is located in the liquid-phase photooxidation tank 1 and is opposite to the ultraviolet lamp 8. The top of the evaporator 2 in this embodiment is also provided with a fluorine-containing olefin outlet 9. The fluorine-containing olefin outlet 9 recovers the fluorine-containing olefins that have not been completely converted. This implementation The top of the fluorination reaction kettle 3 of the example is also provided with a gas inlet 10, and the fluorine gas diluted with nitrogen enters the fluorination reaction kettle 3 through the gas inlet 10, and the fluorination reaction kettle 3 is provided with an agitator II 11. The vacuum rectification tower 4 of the example is set as an interstitial vacuum rectification tower.

The present invention is further illustrated by the following examples: In a liquid-phase photooxidation kettle 1 with an internal volume of 10 liters, nitrogen exhaust and dehumidification are first used, and the jacket temperature is reduced to minus 70 degrees, and then the liquid-phase photooxidation kettle 1 is filled. Feed in 9.5 kg of fluorine-containing monomer, which contains 80% hexafluoropropylene and 20% tetrafluoroethylene. At this time, the fluorine-containing monomer is basically completely liquefied, stirred by the mixer I7, and the ultraviolet lamp 8 with a power of about 300 watts is turned on. Carry out irradiation, start to feed oxygen into the bottom of the kettle, oxygen is about 36 liters/minute, and trifluorochloromethane is also introduced at the same time, trifluorochloromethane is about 41 liters/minute, and the temperature in the kettle is controlled at -50~-70°C After about 5 hours of reaction, stop stirring, discharge the reaction materials into the 10L evaporator that has been evacuated, use steam to heat, discharge unreacted monomers, use residual pressure to press the reaction product into the fluorination reaction kettle 3, and use the electronic scale 1.23 kg of material was obtained, and the mixed F2/N2 was circulated, stirred for 2 hours, and then purged with nitrogen, and 50g was sampled for peroxygen value analysis. 96g/kg, all the other materials are pressed into vacuum rectification tower 4, in order to prevent peroxide decomposition, rectification is lower than -0.098Mpa in vacuum pressure, rectification under the condition of temperature lower than 90 ℃, and the top of the tower obtains the different cuts Perfluoropolyether-based peroxides, and perfluoropolyether products.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention, and the present invention The scope is determined by the scope of the appended claims.

Claims (10)

1. A preparation method of oligomeric fluoroether peroxide for fluororubber is characterized by comprising the following steps:

mixing high-purity oxygen and a gas-phase polymerization regulator according to a certain proportion, introducing the mixture into a liquid-phase photooxidation kettle (1) containing fluorine-containing olefin at a certain speed, carrying out oxygen removal and dehumidification on the liquid-phase photooxidation kettle (1) by adopting nitrogen, carrying out irradiation reaction for a period of time by ultraviolet light emitted by an ultraviolet lamp (8) under the stirring of a stirrer I (7) at a certain temperature and under a certain pressure, and converting the fluorine-containing olefin into a mixed product of perfluoropolyether group acyl peroxide fluoride and perfluoropolyether acyl fluoride;

step two, discharging the mixture generated in the step one into a fluorination reaction kettle (3) after being evaporated at 210 ℃ by an evaporator (2), introducing fluorine gas diluted by nitrogen, stirring to generate fluorination reaction, and removing acyl fluoride to form a stable end group;

and step three, finally introducing the mixture into a vacuum rectification tower (4) to separate perfluoropolyether peroxide and perfluoropolyether of different fractions by vacuum rectification.

2. The process for producing an oligomeric fluoroether peroxide for fluororubber according to claim 1, wherein the volume ratio of the mixture of the high purity oxygen and the gas phase telomer is 1.

3. The process for producing an oligofluoroether peroxide for fluororubber according to claim 1, wherein the fluoroolefin is one or a mixture of octafluoro-2-butene (cis or trans CF3CF = CFCF 3), octafluoro-1-butene (CF 3CF2CF = CF 2), hexafluoropropylene (CF 3CF = CF 2), perfluoroisobutylene (CF 2= C (CF 3) 2), tetrafluoroethylene (CF 2= CF 2), and hexafluorocyclobutene (C4F 6).

4. The process for producing an oligomeric fluoroether peroxide for fluororubber according to claim 1, wherein the ratio of nitrogen in the fluorine gas diluted in the step two to nitrogen: fluorine gas = 1.

5. The process for producing an oligomeric fluoroether peroxide for fluororubber according to claim 1, wherein the temperature of the top fraction in the vacuum distillation column (4) in the third step is from 35 to 90 ℃ and the temperature of the bottom fraction in the vacuum distillation column is from 35 to 90 ℃, and the mixed product comprises 10 to 50% by mass of the perfluoropolyether-based peroxide.

6. The utility model provides a preparation facilities of oligomeric fluoroether peroxide for fluororubber, characterized by it mainly includes liquid phase photooxidation cauldron (1), evaporimeter (2), fluoridize reation kettle (3) and decompression rectifying column (4), the feed inlet of liquid phase photooxidation cauldron (1) is located the upper portion of the cauldron body, the discharge gate of liquid phase photooxidation cauldron (1) is located the bottom of the cauldron body, the discharge gate of liquid phase photooxidation cauldron (1) is linked together with the top import of evaporimeter (2), the bottom export of evaporimeter (2) is linked together with the top feed inlet of fluoridizing reation kettle (3), the bottom discharge gate of fluoridizing reation kettle (3) is linked together with the import of decompression rectifying column (4) bottom, decompression rectifying column (4) top is equipped with rectification product export (5), still be equipped with heavy ends of the tower of decompression rectifying column (4) export (6).

7. The apparatus for producing an oligomeric fluoroether peroxide for fluororubber according to claim 6, wherein the liquid phase photooxidation reactor (1) is provided therein with a stirrer I (7) and an ultraviolet lamp (8), the stirrer I (7) being disposed opposite to the ultraviolet lamp (8) in the liquid phase photooxidation reactor (1).

8. The apparatus for producing an oligomeric fluoroether peroxide for fluororubber according to claim 6, wherein the evaporator (2) has a fluorinated olefin outlet (9) at the top thereof, and the fluorinated olefin which has not been completely converted is recovered from the fluorinated olefin outlet (9).

9. The apparatus for producing an oligomeric fluoroether peroxide for fluororubber according to claim 6, wherein the fluorination reactor (3) is further provided at the top with a gas inlet (10), fluorine gas diluted with nitrogen gas is introduced into the fluorination reactor (3) through the gas inlet (10), and the fluorination reactor (3) is provided with a stirrer II (11).

10. The apparatus for producing an oligomeric fluoroether peroxide for fluororubber according to claim 6, wherein said vacuum distillation column (4) is a batch vacuum distillation column.

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