CN102702035B - Method for continuously preparing fluorinated vinyl ether - Google Patents
Method for continuously preparing fluorinated vinyl ether Download PDFInfo
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- CN102702035B CN102702035B CN2012101932540A CN201210193254A CN102702035B CN 102702035 B CN102702035 B CN 102702035B CN 2012101932540 A CN2012101932540 A CN 2012101932540A CN 201210193254 A CN201210193254 A CN 201210193254A CN 102702035 B CN102702035 B CN 102702035B
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Abstract
The invention discloses a method for continuously preparing fluorinated vinyl ether. Anhydrous carbonate and 2-alkoxy propionyl fluoride are continuously added to a twin-screw extruder according to a molar ratio of 2 to 10:1, are subjected to a salt-forming reaction at a salt-forming section of the twin-screw extruder, and subjected to a decarboxylation reaction at a decarboxylation section to obtain the fluorinated vinyl ether, wherein the starting temperature of the salt-forming section is 60 to 90 DEG C, the final temperature is 180 to 204 DEG C, the temperature is increasingly distributed at a gradient of 0 to 30 DEG C/10cm along with the direction of travel of the materials, the temperature of the decarboxylation section is 180 to 320 DEG C, and the total residence time of the salt-forming reaction and the decarboxylationreaction is 2 to 8min by controlling the extrusion rate of the twin-screw extruder. The method provided by the invention has the advantages of short process flow, continuous operation, good reaction mass transfer and heat transfer, high reaction conversion rate and the like, and the conversion rate is up to 88.2%.
Description
Technical field
The present invention relates to the preparation method of fluorinated vinyl ether, particularly a kind of method of utilizing twin screw extruder continuous production fluorinated vinyl ether.
Background technology
Fluorinated ethylene base ether is the important comonomer of organic fluorine material, and Main Function is that the functional groups chain is incorporated in polymkeric substance, improves or strengthen the performance of some aspect of polymkeric substance.
According to the literature, the fluorinated vinyl ether synthetic technology mainly contains following two kinds at present:
1) directly salify, decarboxylic reaction obtain fluorinated vinyl ether in fixed-bed reactor, tubular reactor or fluidized-bed to make 2-alkoxypropionyl fluoride and carbonate.Such technique is first carbonate to be placed in reactor, add again the reaction of 2-alkoxypropionyl fluoride, as China Patent Publication No. CN101213168A, open day on July 2nd, 2008, denomination of invention: the preparation method of fluorinated vinyl ether, this application case discloses a kind of method for preparing in the following manner fluorinated vinyl ether, and described mode is: 2-alkoxypropionyl fluoride and metal carbonate are reacted in the agitated bed reactor of temperature higher than the decarboxylation temperature of intermediate carboxylate.Described method is to implement under the condition that does not have solvent.This invents described method, can obtain highly purified fluorinated vinyl ether in high-throughout mode.Weak point is to realize the continuously feeding of carbonate, the control of temperature, the mass transfer of reaction, the difficulty of conducting heat, reaction product is more difficult in time to be spread out of, and reaction heat can not effectively shift, make the side reactions such as easy generation disproportionation reaction, cause the shortcomings such as reaction yield is low, selectivity is not high.
First the 2-alkoxypropionyl fluoride is completed and mixed salify at the temperature of the decomposition temperature lower than its salt-forming reaction thing with metal carbonate, then the temperature decarboxylic reaction that raises produces fluorinated vinyl ether.As China Patent Publication No. CN1520393A, in open day on August 11st, 2004, denomination of invention: the preparation method of fluorinated vinyl ether, this invention provides by simple operations from having as the ester group of hydroxy-acid group precursor or as the SO of sulfonic acid group precursor
2The acid fluoride of F is made the method for fluorinated vinyl ether with high yield.Weak point is to exist operation steps many, the shortcoming such as can not produce continuously,, due to the existence of solvent, also exists side reaction to increase phenomenons such as (for example, the HF affixtures of fluorinated vinyl ether) simultaneously.
Summary of the invention
The present invention is directed to the deficiencies in the prior art part, provide that a kind of technique is simple, yield is high, cost is low, the continuous production method of the fluorinated vinyl ether of energy-conserving and environment-protective.
in order to solve the problems of the technologies described above, the technical solution used in the present invention is: a kind of continuous production method of fluorinated vinyl ether, be that 2～10:1 adds anhydrous carbonate and 2-alkoxypropionyl fluoride continuously to twin screw extruder in molar ratio, carry out salt-forming reaction through twin screw extruder salify section, the decarboxylation section is carried out decarboxylic reaction and is obtained fluorinated vinyl ether, described salify section starting temperature is 60～90 ℃, terminal temperature is 180～204 ℃, and the gradient rising that is 20～30 ℃/10cm with the material direct of travel distributes, decarboxylation section temperature is 180～320 ℃, by controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 2～8min.
Further:
Described carbonate is sodium carbonate or salt of wormwood.
Described 2-alkoxypropionyl fluoride is by general formula X-(O-Y)
a-O-CF (CF
3) COF represents, wherein, it is 1 to 3 C that X is selected from n
nF
2n+1Or FSO
2(C
2F
4); It is 1 to 3 C that Y is selected from as p
PF
2PA is 0 to 2.
Described 2-alkoxypropionyl fluoride is selected from FSO
2CF
2CF
2OCF (CF
3) CF
2OCF (CF
3) COF, FSO
2CF
2CF
2OCF (CF
3) COF, FSO
2CF
2CF
2(OCF (CF
3) CF
2)
2OCF (CF
3) COF, CF
3CF
2CF
2OCF (CF
3) COF, CF
3OCF (CF
3) a kind of in COF.
Described salify segment length is 40～55cm, and all the other are the decarboxylation section.
The mol ratio of described 2-alkoxypropionyl fluoride and anhydrous carbonate is 3～8:1.
Described salify section starting temperature is 70～80 ℃, and terminal temperature is 190～200 ℃, and is the gradient rising distribution of 25 ℃/10cm with the material direct of travel.
Described decarboxylation temperature is 190～270 ℃.
The total residence time of described salt-forming reaction and decarboxylic reaction is 3～6min.
The present invention utilizes twin screw extruder to be salify, decarboxylic reaction device, 2-alkoxypropionyl fluoride and anhydrous carbonate are raw material, control the carbonate feed rate with the solid continuous feeder, control 2-alkoxypropionyl fluoride feed rate with microprocessor pump drive, shear and complete the mixing of anhydrous metal carbonate and 2-alkoxypropionyl fluoride by the rotation of screw rod, and realize that continuous decarboxylic reaction prepares fluorinated vinyl ether.
In the present invention, the salt-forming reaction of 2-alkoxypropionyl fluoride and carbonate is carried out in the salify section of twin screw extruder, and decarboxylic reaction carries out in the decarboxylation section of twin screw extruder; Described salify section refers to that temperature on twin screw extruder is the interval of 60～204 ℃, and the decarboxylation section refers to that temperature is in the interval of 180～320 ℃; Described salify segment length is 40～55cm, and all the other are the decarboxylation section.
The kind of carbonate is different, causes carbonate different with the organic carboxyl acid salify thing that the reaction of 2-alkoxypropionyl fluoride obtains.Usually the sylvite of organic carboxyl acid is solid-state under decarboxylation temperature, and the sodium salt of organic carboxyl acid is the fused solution of thickness under decarboxylation temperature.Organic carboxylate is comparatively easy in solid-state lower decarboxylation meeting, and can have more serious mass transfer problem under molten state, thereby causes the side reaction aggravation, reduces reaction preference.But because the purity of salt of wormwood is often lower than sodium carbonate, and price is high, makes to utilize salt of wormwood to substitute sodium carbonate also and may not be certain to produce better economy.In the present invention,, owing to having adopted the twin screw extruder with good cutting performance as reactor, make its heat transfer, mass-transfer performance obtain obvious improvement, so carbonate both can select salt of wormwood, also can select sodium carbonate.
Salt-forming reaction need to provide certain energy, and temperature is too low, can cause salt-forming reaction speed slow, makes the length of salify section very long, or the prolongation of salify required time, and salt-forming reaction can't be carried out; Excess Temperature may cause the vaporization of 2-alkoxypropionyl fluoride or can cause limit to become the phenomenon of Yanbian decarboxylation to occur, and causes that the material contact is inhomogeneous, makes salify incomplete, reduces product yield; The salify temperature raises the major cause that distributes for can make the 2-alkoxypropionyl fluoride complete salt-forming reaction at lower temperature in gradient with the material direct of travel, makes simultaneously material complete warm, in order to carry out decarboxylic reaction of lower step.Therefore, it is 60～90 ℃ that the present invention selects salify section starting temperature, is preferably 70～80 ℃; Terminal temperature is 180～204 ℃, is preferably 190～200 ℃; And be 20～30 ℃/10cm with the material direct of travel, the gradient that is preferably 25 ℃/10cm raises and distributes.
Decarboxylation temperature is low, can make decarboxylic reaction speed slow, makes the length of decarboxylation section very long, maybe needs to extend the reaction times; Decarboxylation temperature is too low, also can cause decarboxylic reaction to carry out smoothly; And decarboxylation temperature is too high, can cause the side reactions such as disproportionation reaction, causes reaction preference to descend, the problems such as the difficult control of reaction.Therefore, the present invention selects the temperature of decarboxylation section at 180～320 ℃, preferred 190～270 ℃.
The residence time of material in twin screw extruder is too short, and decarboxylation is incomplete, causes the low conversion rate of 2-alkoxypropionyl fluoride; Reaction time is oversize, the side reactions such as material pyrolytic decomposition more easily occur, and reaction efficiency is lower.Therefore, the total residence time that the present invention is chosen to reactant salt and decarboxylic reaction is 2～8min, is preferably 3～6min.
The mol ratio of 2-alkoxypropionyl fluoride and anhydrous carbonate is lower, and the salify transformation efficiency of 2-alkoxypropionyl fluoride is higher, and the selectivity of 2-alkoxypropionyl fluoride is also higher.But mol ratio is too low, can cause the waste of carbonate, causes the increase of cost and the increase of useless solid amount.Therefore it is 2～10:1 that the present invention selects the mol ratio without 2-alkoxypropionyl fluoride and anhydrous carbonate, preferred 3～8:1.
In addition, the moisture content in the material carbon hydrochlorate is also one of important factor that affects decarboxylic reaction.Easily cause the generation of side reaction due to the existence of moisture content, generate hydrogeneous by product, the degradation of polymkeric substance while causing the follow-up polymerization of fluorinated vinyl ether.Therefore to select anhydrous carbonate be raw material in the present invention.
Advantage of the present invention is: make the salt-forming reaction of anhydrous carbonate and 2-alkoxypropionyl fluoride and the decarboxylic reaction of salt thereof be carried out continuously in twin screw extruder, effectively solve mass transfer, the heat transfer problem in the reaction, improved transformation efficiency and the reaction preference of reaction.Have technical process short, but operate continuously reaction mass transfer, conduct heat, the reaction conversion ratio advantages of higher, transformation efficiency is up to 88.2%.
Description of drawings
Fig. 1 is process flow sheet of the present invention.
As shown in the figure: 1 is solid feed inlet, and 2 is the liquid charging opening, and 3 is the salify section, and 4 are the decarboxylation section.
Embodiment
Below by drawings and Examples, the present invention is further elaborated, but the present invention is not limited to described embodiment.
CTE-SC-25 type twin screw extruder (the screw diameter 25mm that the present invention uses Nanjing Pohle agate mechanical means company limited to produce, length-to-diameter ratio 48), CTE-SC-25 type twin screw extruder mainly comprises drive-motor, shaft coupling, wheel casing, solid charging system, mixing and conveying system, exhaust system, screw rod, machine barrel and machine barrel well heater outward etc.; For being applicable to this technique, the present invention has increased the liquid charging opening newly to the twin screw extruder of purchasing.
Embodiment 1
Utilize simultaneously the solid continuous feeder to add continuously anhydrous sodium carbonate, utilize microprocessor pump drive to add continuously FSO to the liquid charging opening 2 of twin screw extruder to the solid feed inlet 1 of twin screw extruder
2CF
2CF
2OCF (CF
3) CF
2OCF (CF
3) COF; The length of salify section 3 is 48cm, and all the other are decarboxylation section 4; The starting temperature of controlling salify section 3 is 60 ℃, and terminal temperature is 204 ℃, and is the gradient rising of 30 ℃/10cm with the material direct of travel; The minimum temperature of controlling decarboxylation section 4 is 204 ℃, and top temperature is 230 ℃; Control FSO
2CF
2CF
2OCF (CF
3) CF
2OCF (CF
3) raw materials components mole ratio of COF and sodium carbonate is 8:1; By controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 6min, and FSO is collected in condensation
2CF
2CF
2OCF (CF
3) CF
2-OCF=CF
2, based on FSO
2CF
2CF
2OCF (CF
3) CF
2OCF (CF
3) yield of COF is 77.3%.
Utilize simultaneously the solid continuous feeder to add continuously Anhydrous potassium carbonate, utilize microprocessor pump drive to add continuously FSO to the liquid charging opening 2 of twin screw extruder to the solid feed inlet 1 of twin screw extruder
2CF
2CF
2OCF (CF
3) COF; The length of salify section 3 is 45cm, and all the other are decarboxylation section 4; The starting temperature of controlling salify section 3 is 90 ℃, and terminal temperature is 180 ℃, and is the gradient rising of 20 ℃/10cm with the material direct of travel; The minimum temperature of controlling decarboxylation section 4 is 180 ℃, and top temperature is 300 ℃; Control FSO
2CF
2CF
2OCF (CF
3) COF and salt of wormwood raw materials components mole ratio be 10:1; By controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 2min, and crude product FSO is collected in condensation
2CF
2CF
2OCF=CF
2, based on FSO
2CF
2CF
2OCF (CF
3) yield of COF is 83.7%.
Utilize simultaneously the solid continuous feeder to add continuously Anhydrous potassium carbonate, utilize microprocessor pump drive to add continuously FSO to the liquid charging opening 2 of twin screw extruder to the solid feed inlet 1 of twin screw extruder
2CF
2CF
2(OCF (CF
3) CF
2)
2OCF (CF
3) COF; The length of salify section 3 is 50cm, and all the other are decarboxylation section 4; The starting temperature of controlling salify section 3 is 90 ℃, and terminal temperature is 190 ℃, and is the gradient rising of 20 ℃/10cm with the material direct of travel; The minimum temperature of controlling decarboxylation section 4 is 190 ℃, and top temperature is 230 ℃, controls FSO
2CF
2CF
2(OCF (CF
3) CF
2)
2OCF (CF
3) COF and Anhydrous potassium carbonate raw materials components mole ratio be 3:1; By controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 3min, and crude product FSO is collected in condensation
2CF
2CF
2(OCF (CF
3) CF
2)
2OCF=CF
2, based on FSO
2CF
2CF
2(OCF (CF
3) CF
2)
2OCF (CF
3) yield of COF is 78.6%.
Embodiment 4
Utilize simultaneously the solid continuous feeder to add continuously anhydrous sodium carbonate, utilize microprocessor pump drive to add continuously CF to the liquid charging opening 2 of twin screw extruder to the solid feed inlet 1 of twin screw extruder
3CF
2CF
2OCF (CF
3) COF; The length of salify section 3 is 45cm, and all the other are decarboxylation section 4; The starting temperature of controlling salify section 3 is 90 ℃, and terminal temperature is 180 ℃, and is the gradient rising of 20 ℃/10cm with the material direct of travel; The minimum temperature of controlling decarboxylation section 4 is 180 ℃, and top temperature is 270 ℃; Control CF
3CF
2CF
2OCF (CF
3) COF and anhydrous sodium carbonate raw materials components mole ratio be 2:1; By controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 5min, and crude product CF is collected in condensation
3CF
2CF
2OCF=CF
2, based on CF
3CF
2CF
2OCF (CF
3) the COF yield is 72.9%.
Embodiment 5
Utilize simultaneously the solid continuous feeder to add continuously anhydrous sodium carbonate, utilize microprocessor pump drive to add continuously CF to the liquid charging opening 2 of twin screw extruder to the solid feed inlet 1 of twin screw extruder
3OCF (CF
3) COF; The length of salify section 3 is 48cm, and all the other are decarboxylation section 4; The starting temperature of controlling salify section 3 is 60 ℃, and terminal temperature is 204 ℃, and is the gradient rising of 30 ℃/10cm with the material direct of travel; The minimum temperature of controlling decarboxylation section 4 is 204 ℃, and top temperature is 250 ℃; Control CF
3OCF (CF
3) COF and anhydrous sodium carbonate raw materials components mole ratio be 6:1; By controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 8min, and crude product CF is collected in condensation
3OCF=CF
2, based on CF
3OCF (CF
3) yield of COF is 88.2%.
Claims (8)
1. the continuous production method of a fluorinated vinyl ether, is characterized in that to be 2～10:1 in molar ratio add anhydrous carbonate and by general formula X-(O-Y) continuously to twin screw extruder
a-O-CF (CF
3) the 2-alkoxypropionyl fluoride that represents of COF, wherein, it is 1 to 3 C that X is selected from n
nF
2n+1Or FSO
2(C
2F
4); It is 1 to 3 C that Y is selected from as p
PF
2PA is 0 to 2, through twin screw extruder salify section carry out salt-forming reaction, the decarboxylation section is carried out decarboxylic reaction and is obtained fluorinated vinyl ether, described salify section starting temperature is 60～90 ℃, terminal temperature is 180～204 ℃, and the gradient rising that is 20～30 ℃/10cm with the material direct of travel distributes, decarboxylation section temperature is 180～320 ℃, and by controlling the twin screw extruder rate of extrusion, the total residence time that makes salt-forming reaction and decarboxylic reaction is 2～8min.
2. the continuous production method of fluorinated vinyl ether according to claim 1, is characterized in that described carbonate is sodium carbonate or salt of wormwood.
3. the continuous production method of fluorinated vinyl ether according to claim 1, is characterized in that described 2-alkoxypropionyl fluoride is selected from FSO
2CF
2CF
2OCF (CF
3) CF
2OCF (CF
3) COF, FSO
2CF
2CF
2OCF (CF
3) COF, FSO
2CF
2CF
2(OCF (CF
3) CF
2)
2OCF (CF
3) COF, CF
3CF
2CF
2OCF (CF
3) COF, CF
3OCF (CF
3) a kind of in COF.
4. the continuous production method of fluorinated vinyl ether according to claim 1, is characterized in that described salify segment length is 40～55cm, and all the other are the decarboxylation section.
5. the continuous production method of fluorinated vinyl ether according to claim 1, the mol ratio that it is characterized in that described 2-alkoxypropionyl fluoride and anhydrous carbonate is 3～8:1.
6. the continuous production method of fluorinated vinyl ether according to claim 1, is characterized in that described salify section starting temperature is 70～80 ℃, and terminal temperature is 190～200 ℃, and be the gradient rising distribution of 25 ℃/10cm with the material direct of travel.
7. the continuous production method of fluorinated vinyl ether according to claim 1, is characterized in that described decarboxylation temperature is 190～270 ℃.
8. the continuous production method of fluorinated vinyl ether according to claim 1, the total residence time that it is characterized in that described salt-forming reaction and decarboxylic reaction is 3～6min.
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| KR102477300B1 (en) * | 2020-07-07 | 2022-12-13 | 한국화학연구원 | Method for preparing perfluoropropyl vinyl ether with high conversion rate |
| CN114917855B (en) * | 2022-05-25 | 2024-03-12 | 金华永和氟化工有限公司 | Reaction system and method for continuously preparing perfluoroalkyl vinyl ether |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6114441A (en) * | 1997-07-25 | 2000-09-05 | E. I. Du Pont De Nemours And Company | Blends of grafted fluoropolymer and polyester |
| CN1520393A (en) * | 2001-06-29 | 2004-08-11 | ������������ʽ���� | Process for producing fluorinated vinyl ether |
| CN101213168A (en) * | 2005-06-30 | 2008-07-02 | 3M创新有限公司 | Method of making fluorinated vinyl ethers |
-
2012
- 2012-06-08 CN CN2012101932540A patent/CN102702035B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6114441A (en) * | 1997-07-25 | 2000-09-05 | E. I. Du Pont De Nemours And Company | Blends of grafted fluoropolymer and polyester |
| CN1520393A (en) * | 2001-06-29 | 2004-08-11 | ������������ʽ���� | Process for producing fluorinated vinyl ether |
| CN101213168A (en) * | 2005-06-30 | 2008-07-02 | 3M创新有限公司 | Method of making fluorinated vinyl ethers |
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