A catalytic process for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer

Abstract

The application provides a catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, and belongs to the technical field of fluorinated ether synthesis. The 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether is synthesized from oxalic acid bis(2,2-difluoroethyl ester) and hexafluoropropylene dimer, so that the synthesis process is simplified, and the production cost is significantly reduced. In addition, the method uses an ester to replace a fluorinated alcohol, so that the generation of fluorinated salt substances in a side reaction is avoided, and the purity of the product is significantly improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of fluorinated ether synthesis, in particular to a catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer. BACKGROUND

[0002] The fluorinated ether is a new type of ODS substitute, has zero ODP value, low GWP value, short atmospheric residence time, and is considered as one of ideal substitutes for ODS. In addition to excellent environmental properties, the fluorinated ether also has low toxicity, non-corrosiveness, easy storage and transportation and the like, and is widely used in the fields of foaming agent, cleaning agent, solvent, battery electrolyte and the like. Therefore, a preparation method thereof has become a research hotspot.

[0003] Patent document JP2003291456 provides a fluorine-containing alkyl ether manufacturing method which can obtain a satisfactory reaction speed under mild reaction conditions, and can efficiently implement a subsequent process such as distillation after the reaction. That is, after introducing aprotic polar solvent, fluorine-containing ether, catalyst, fluorine-containing alkanol and fluorinated olefin into a reaction vessel, the fluorine-containing alkanol and the fluorinated olefin are reacted to manufacture the fluorine-containing alkyl ether, and the ratio of the two components introduced into the reaction vessel, that is, the aprotic polar solvent and the fluorine-containing ether, is 5 / 95-80 / 20 in mass ratio.

[0004] Patent document CN107353184B relates to a method for preparing hydrofluoroether by taking 1,1,1,2-tetrafluoroethane as a raw material, which comprises the following steps: loading a catalyst into a gas phase reactor, introducing N2, drying the catalyst under the N2 atmosphere, and stopping the introduction of N2; then continuously introducing 1,1,1,2-tetrafluoroethane, removing HF at 250-550 DEG C for 1-10 h, washing and drying to obtain an intermediate product A; under the catalysis of a base, alcohol and the obtained intermediate product A are subjected to an addition reaction in an organic solvent at 50-150 DEG C under a pressure of 0.1-0.8 MPa for 5-10 h, and hydrofluoroether is obtained through distillation. The present application directly prepares hydrofluoroether by using a two-step method, which can avoid the separation of trifluoroethylene, effectively solves the problem of difficult preparation of corresponding hydrofluoroether product caused by the difficulty in preparation and separation of pure trifluoroethylene, and effectively improves the yield and selectivity of hydrofluoroether.

[0005] However, in the prior art, the synthesis of fluorinated ethers from alcohols and fluorine-containing olefins generally produces side reactions such as defluorination of fluorinated ethers to form enol ethers and hydrolysis of fluorinated olefins in the presence of a base. The enol ethers and fluorinated olefins produced by the side reactions are easily hydrolyzed in the presence of a basic catalyst to produce fluorinated salt substances. These fluorinated salt substances and other solid by-products form fine particle solid residues in the form of precipitates with the basic catalyst after the reaction is completed. On the one hand, this affects the yield and purity of the fluorinated ether product, and on the other hand, it also increases the production cost and the difficulty of waste treatment.

[0006] Therefore, the present application provides a catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer. SUMMARY

[0007] The present application provides a catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, which solves at least one of the technical problems in the background art and belongs to the technical field of fluorinated ether synthesis.

[0008] To achieve the above-mentioned application purposes, the present application adopts the following technical solutions:

[0009] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized in that it comprises the following operation steps:

[0010] According to weight parts, 600-1000 parts of an organic solvent are added to a reaction container, followed by the addition of 172-234 parts of bis(2,2-difluoroethyl) oxalate and 480-720 parts of hexafluoropropylene dimer. Stirring is started, the reaction container is heated to a set temperature, and then 260-320 parts of a mixed solution composed of deionized water and a catalyst are added dropwise for reaction. After the dropwise addition is completed, the reaction is continued for 2-4 h, and then the reaction solution is cooled, filtered, and distilled to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0011] As a preferred embodiment of the present application, the organic solvent is selected from one of acetonitrile, sulfolane, dimethyl sulfoxide, tetrahydrofuran, methyl tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, methyl tert-butyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, and cyclohexanone.

[0012] As a preferred embodiment of the present application, the stirring speed is 80-120 rpm.

[0013] As a preferred embodiment of the present application, the reaction temperature is 45-60℃.

[0014] As a preferred embodiment of the present application, the ratio of deionized water to catalyst is 1:4-8.

[0015] As a preferred embodiment of the present application, the dropping time of the mixed liquid of the deionized water and the catalyst is 2-4h.

[0016] As a preferred embodiment of the present application, the catalyst is a solid base catalyst, and the preparation method thereof is as follows:

[0017] S1: 100-140 parts of dry base quaternary ammonium salt type anion exchange resin, 30-50 parts of acryloyl chloride, 500-1000 parts of dichloroethane, and 10-20 parts of zinc chloride are weighed in a stirring reaction kettle, and stirred at 20-30℃ for 10-16 hours to obtain a propenyl quaternary ammonium salt type anion exchange resin;

[0018] S2: 15-30 parts of 2,5-dimercaptothiazole, 0.005-0.05 parts of methacryl cage type silsesquioxane, and 0.5-2.5 parts of allyl amine salt are added in a sealed high-pressure reaction kettle, 1-3 parts of ionic liquid catalyst is added, heated to 70-80℃ and reacted for 40-90 minutes, filtered and dried to obtain intermediate 1;

[0019] S3: Intermediate 1 is placed in a glass exchange chamber, which accounts for 20-30% of the volume of the exchange chamber, water is added to cover the surface of the resin, then sodium hydroxide with a mass percentage content of 10-20% is added at a flow rate of 0.5-2BV / h, the column is added dropwise, filtered and dried to obtain a solid base catalyst.

[0020] As a preferred embodiment of the present application, the dry base quaternary ammonium salt type anion exchange resin is selected from D201, 717 resin, and the factory type is quaternary ammonium salt type.

[0021] As a preferred embodiment of the present application, the allyl amine salt is selected from allyl amine hydrochloride or diallyl amine hydrochloride, and water is removed by drying before use.

[0022] As a preferred embodiment of the present application, the ionic liquid catalyst is selected from any one of [Bmim]OH, [Emim]OH, [Hmim]OH, and [Omim]OH.

[0023] The reaction mechanism of the present application is as follows:

[0024] In the present method, the propenyl quaternary ammonium salt type anion exchange resin introduces propenyl groups onto the benzene ring of styrene, and then combines with 2,5-dimercaptothiazole, methacryl cage type silsesquioxane, and allyl amine salt through addition reaction, and is ion exchanged into a solid base catalyst.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] (1) The method synthesizes 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether by using oxalic acid bis(2,2-difluoroethyl) and hexafluoropropylene dimer, simplifies the synthesis process, and significantly reduces the production cost;

[0027] (2) The method uses ester instead of fluorinated alcohol, thereby avoiding the generation of fluorinated salt substances by side reactions, and significantly improving the purity of the product.

[0028] (3) The method uses cage polysilsesquioxane to improve the heat resistance of the solid base catalyst, which can prevent the resin from being broken by heat and prolong the service life.

[0029] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be combined with each other, that is, the preferred embodiments of the present application are obtained. DETAILED DESCRIPTION

[0030] The present application will be further described in conjunction with specific examples, but the present application is not limited to these specific embodiments. Those skilled in the art should realize that the present application encompasses all alternatives, improvements and equivalents within the scope of the claims.

[0031] Methylpropyl cage polysilsesquioxane; CAS No.: 1204591-17

[0032] <Example 1>

[0033] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized by comprising the following operation steps:

[0034] 600g of organic solvent is added to the reaction container, followed by the addition of 172g of oxalic acid bis(2,2-difluoroethyl) and 480g of hexafluoropropylene dimer, stirring is started, the reaction container is heated to the set temperature, and then 260g of a mixture of deionized water and catalyst is added dropwise to start the reaction. After the dropwise addition is completed, the reaction is continued for 2h at room temperature, and then the reaction solution is cooled, filtered and distilled to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0035] The organic solvent is selected from acetonitrile.

[0036] The stirring speed is 80rpm.

[0037] The reaction temperature is 45°C.

[0038] The ratio of deionized water to catalyst is 1:4.

[0039] The dropwise addition time of the mixture of deionized water and catalyst is 2h.

[0040] The catalyst is a solid base catalyst, and the preparation method is:

[0041] S1: Take 100 g of dry base quaternary ammonium salt type anion exchange resin, 30 g of acryloyl chloride, 500 g of dichloroethane, and 10 g of zinc chloride into a stirring reaction kettle, stir for 10 hours at 20°C, and obtain acryl quaternary ammonium salt type anion exchange resin;

[0042] S2: Add 15 g of 2,5-dimercaptothiazole, 0.01 g of methyl methacryl cage type silsesquioxane, and 0.5 g of allyl amine salt into a sealed high-pressure reaction kettle, add 1 g of ionic liquid catalyst, heat to 70°C for 40 minutes, filter, and spin dry to obtain intermediate 1;

[0043] S3: Put intermediate 1 into a glass exchange house, which accounts for 20% of the volume of the exchange house, add water to cover the surface of the resin, then add 2 times the volume of the exchange house with 10% mass fraction of sodium hydroxide, and drop at a flow rate of 0.5 BV / h, after the column is over, filter, and dry to obtain a solid base catalyst.

[0044] The dry base quaternary ammonium salt type anion exchange resin is selected from D201, and the factory type is quaternary ammonium salt type.

[0045] The allyl amine salt is selected from allyl amine hydrochloride, which is dried to remove water before use.

[0046] The ionic liquid catalyst is selected from [Bmim]OH.

[0047] After analysis and calculation, the yield of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether prepared in the embodiment is 91%, and the product purity is 99.6%.

[0048] <Example 2>

[0049] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized in that it comprises the following operation steps:

[0050] Add 800 g of organic solvent, then add 212 g of oxalic acid di(2,2-difluoroethyl ester) and 620 g of hexafluoropropylene dimer into a reaction container, start stirring, heat the reaction container to the set temperature, then start dropping 290 g of a mixture composed of deionized water and catalyst for reaction, continue to heat for 3 h after the dropping is completed, then cool, filter and rectify the reaction liquid to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0051] The organic solvent is selected from tetrahydrofuran.

[0052] The stirring speed is 100 pm.

[0053] The reaction temperature is 55℃.

[0054] The ratio of deionized water to catalyst is 1:6.

[0055] The dropwise addition time of the mixed liquid of deionized water and catalyst is 3h.

[0056] The catalyst is a solid base catalyst, and the preparation method is:

[0057] S1: Take 120g of dry base quaternary ammonium salt type anion exchange resin, 40g of acryloyl chloride, 750g of dichloroethane, and 15g of zinc chloride into a stirring reaction kettle, stir for 13 hours at 25℃, and obtain acryl quaternary ammonium salt type anion exchange resin;

[0058] S2: Add 25g of 2,5-dimercaptothiazole, 0.025g of methyl methacryl cage type silsesquioxane, and 1.5g of allyl amine salt into a sealed high-pressure reaction kettle, add 2g of ionic liquid catalyst, heat to 75℃ and react for 65 minutes, filter and dry to obtain intermediate 1;

[0059] S3: Put intermediate 1 into a glass exchange house, which accounts for 25% of the volume of the exchange house, add water to cover the surface of the resin, then add 4 times the volume of the exchange house with 15% mass percentage of sodium hydroxide, and dropwise add through the column at a flow rate of 1.5BV / h, filter and dry after the column is finished, to obtain a solid base catalyst.

[0060] The dry base quaternary ammonium salt type anion exchange resin is selected from 717 resin, and the factory type is quaternary ammonium salt type.

[0061] The allyl amine salt is selected from diallyl amine hydrochloride, which is dried to remove water before use.

[0062] The ionic liquid catalyst is selected from [Emim]OH.

[0063] Through analysis and calculation, the yield of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether prepared in the embodiment is 93%, and the product purity is 99.8%.

[0064] <Example 3>

[0065] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized in that it comprises the following operation steps:

[0066] In a reaction vessel, 1000g of organic solvent was added, followed by 234g of oxalic acid di(2,2-difluoroethyl ester) and 720g of hexafluoropropylene dimer, stirring was started, the reaction vessel was heated to the set temperature, and then 320g of a mixture of deionized water and catalyst was added dropwise, the reaction was continued for 4h after the dropwise addition was completed, and then the reaction solution was cooled, filtered, and distilled to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0067] The organic solvent is selected from N,N-dimethylformamide.

[0068] The stirring speed is 120rpm.

[0069] The reaction temperature is 60℃.

[0070] The ratio of deionized water to catalyst is 1:8.

[0071] The dropwise addition time of the mixture of deionized water and catalyst is 4h.

[0072] The catalyst is a solid base catalyst, and its preparation method is:

[0073] S1: 140g of dry base quaternary ammonium salt type anion exchange resin, 50g of acryloyl chloride, 1000g of dichloroethane, and 20g of zinc chloride were added to a stirring reaction kettle, stirred at 30℃ for 16h to obtain a propenyl quaternary ammonium salt type anion exchange resin;

[0074] S2: In a sealed high-pressure reaction kettle, 30g of 2,5-dimercaptothiazole, 0.05g of methacryl cage type silsesquioxane, and 2.5g of allyl amine salt were added, 3g of ionic liquid catalyst was added, heated to 80℃ for 90min, filtered, and dried to obtain intermediate 1;

[0075] S3: Intermediate 1 was placed in a glass exchange chamber, which occupied 30% of the volume of the exchange chamber, water was added to cover the surface of the resin, and then 5 times the volume of the exchange chamber of 20% mass fraction sodium hydroxide was added dropwise at a flow rate of 2BV / h, after the column was passed, it was filtered, dried, and a solid base catalyst was obtained.

[0076] The dry base quaternary ammonium salt type anion exchange resin is selected from D201, which is a factory type quaternary ammonium salt.

[0077] The allyl amine salt is selected from allyl amine hydrochloride, which is dried before use to remove water.

[0078] The ionic liquid catalyst is selected from [Hmim]OH.

[0079] After analysis and calculation, the yield of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether prepared in the embodiment is 94%, and the purity of the product is 99.9%.

[0080] <Comparative Example 1>

[0081] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized by comprising the following operation steps:

[0082] 600 g of an organic solvent, then 172 g of bis(2,2-difluoroethyl) oxalate and 480 g of hexafluoropropylene dimer are added into a reaction container, stirring is started, the reaction container is heated to a set temperature, and then 260 g of a mixture of deionized water and a catalyst is added dropwise for reaction, after the dropwise addition is completed, the reaction is continued for 2 h, then the reaction solution is cooled, filtered and distilled to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0083] The organic solvent is selected from acetonitrile.

[0084] The stirring speed is 80 rpm.

[0085] The reaction temperature is 45°C.

[0086] The ratio of deionized water to catalyst is 1:4.

[0087] The dropwise addition time of the mixture of deionized water and catalyst is 2 h.

[0088] The catalyst is a solid base catalyst, and the preparation method is as follows:

[0089] S1: 100 g of dry base quaternary ammonium salt type anion exchange resin, 30 g of acryloyl chloride, 500 g of dichloroethane, and 10 g of zinc chloride are weighed into a stirring reaction kettle, stirred at 20°C for 10 hours to obtain a propenyl quaternary ammonium salt type anion exchange resin;

[0090] S2: 15 g of 2,5-dimercaptothiazole, 0.5 g of allyl amine salt, and 1 g of ionic liquid catalyst are added into a sealed high-pressure reaction kettle, heated to 70°C for 40 minutes, filtered, and dried to obtain an intermediate 1;

[0091] S3: The intermediate 1 is placed in a glass exchange bed, which accounts for 20% of the volume of the exchange bed, water is added to cover the surface of the resin, then 2 times the volume of the exchange bed of sodium hydroxide with a mass percentage of 10% is added dropwise at a flow rate of 0.5 BV / h, after the column is passed, the column is filtered, dried, and a solid base catalyst is obtained.

[0092] The dry base quaternary ammonium salt type anion exchange resin is selected from D201, and the factory type is quaternary ammonium salt type.

[0093] The allyl amine salt is selected from allyl amine hydrochloride, which is dried to remove water before use.

[0094] The ionic liquid catalyst is selected from [Bmim]OH.

[0095] Through analysis and calculation, the yield of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether prepared in the method is 82%, and the purity of the product is 98.2%.

[0096] <Comparative Example 2>

[0097] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized by comprising the following operation steps:

[0098] 600g of an organic solvent is added to a reaction vessel, followed by the addition of 172g of oxalic acid di(2,2-difluoroethyl ester) and 480g of hexafluoropropylene dimer, stirring is started, the reaction vessel is heated to a set temperature, and then 260g of a mixture of deionized water and a catalyst is added dropwise to start the reaction. After the dropwise addition is completed, the reaction is continued for 2h at the same temperature, and then the reaction solution is cooled and filtered to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0099] The organic solvent is selected from methyl tert-butyl ether.

[0100] The stirring speed is 80rpm.

[0101] The reaction temperature is 45℃.

[0102] The ratio of deionized water to catalyst is 1:4.

[0103] The dropwise addition time of the mixture of deionized water and catalyst is 2h.

[0104] The catalyst is a solid base catalyst, and its preparation method is as follows:

[0105] S1: 100g of dry quaternary ammonium salt type anion exchange resin, 500g of dichloroethane, and 10g of zinc chloride are weighed into a stirred reaction kettle, stirred at 20℃ for 10h to obtain a propenyl quaternary ammonium salt type anion exchange resin;

[0106] S2: 15g of 2,5-dimercaptothiazole, 0.01g of methyl propenyl cage type silsesquioxane, and 0.5g of allyl amine salt are added to a sealed high-pressure reaction kettle, 1g of ionic liquid catalyst is added, heated to 70℃ and reacted for 40min, filtered and dried to obtain an intermediate 1;

[0107] S3: Put the intermediate 1 into the glass exchange residence, which accounts for 20% of the exchange residence volume, and then add water to cover the surface of the resin. Then, add 2 times the exchange residence volume of 10% mass percentage sodium hydroxide, and drop it into the column at a flow rate of 0.5 BV / h. After the column is filled, filter and dry to obtain a solid base catalyst.

[0108] The dry base quaternary ammonium salt type anion exchange resin is selected from D201, a factory type quaternary ammonium salt type.

[0109] The allyl amine salt is selected from allyl amine hydrochloride, which is dried to remove water before use.

[0110] The ionic liquid catalyst is selected from [Omim]OH.

[0111] Through analysis and calculation, the yield of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether prepared in the embodiment is 84%, and the product purity is 98.8%.

[0112] <Comparative Example 3>

[0113] A catalytic method for preparing 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropylene dimer, characterized by comprising the following operation steps:

[0114] In the reaction container, 600g of organic solvent is added, followed by 172g of oxalic acid di(2,2-difluoroethyl ester) and 480g of hexafluoropropylene dimer. After the reaction container is heated to the set temperature, 260g of a mixture of deionized water and catalyst is added dropwise for reaction. After the dropwise addition is completed, the reaction is continued for 2h, and then the reaction solution is cooled and filtered to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether.

[0115] The organic solvent is selected from cyclohexanone.

[0116] The stirring speed is 80rpm.

[0117] The reaction temperature is 45℃.

[0118] The ratio of deionized water to catalyst is 1:4.

[0119] The dropwise addition time of the mixture of deionized water and catalyst is 2h.

[0120] The catalyst is a solid base catalyst, and the preparation method is as follows:

[0121] S1: Weigh 100g of dry base quaternary ammonium salt type anion exchange resin, 30g of acryloyl chloride, and 500g of dichloroethane, and add them into a stirred reaction kettle. Stir for 10 hours at 20℃ to obtain a propenyl quaternary ammonium salt type anion exchange resin.

[0122] S2: In a closed high-pressure reaction kettle, 15 g of 2, 5-dithiolthiazole, 0.01 g of methacryl cage silsesquioxane, 0.5 g of allyl amine salt, 1 g of ionic liquid catalyst were added, heated to 70°C for 40 minutes, filtered, and dried to obtain intermediate 1;

[0123] S3: Intermediate 1 was placed in a glass exchange bed, 20% of the volume of the exchange bed, water was added to cover the surface of the resin, then 2 times the volume of the exchange bed of 10% mass fraction of sodium hydroxide was added, and the flow rate was 0.5 BV / h, then the column was added, filtered, dried, and a solid base catalyst was obtained.

[0124] The dry base quaternary ammonium salt type anion exchange resin is selected from D201, a factory type quaternary ammonium salt type.

[0125] The allyl amine salt is selected from allyl amine hydrochloride, which is dried to remove water before use.

[0126] The ionic liquid catalyst is selected from [Bmim]OH.

[0127] Through analysis and calculation, the yield of 1-(hexafluoroisopropyl) perfluoropropyl-2, 2-difluoroethyl ether prepared in the method is 85%, and the purity of the product is 98.9%.

[0128] The above only describes the preferred embodiments of the present application, and it should be noted that for ordinary skilled persons in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A catalytic process for the preparation of 1-(hexafluoroisopropyl)perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized by: The method comprises the following steps: In a reaction vessel, 600-1000 parts of an organic solvent, then 172-234 parts of bis(2,2-difluoroethyl) oxalate and 480-720 parts of hexafluoropropylene dimer are added, stirring is started, the reaction vessel is heated to a set temperature, then 260-320 parts of a mixture of deionized water and a catalyst are added dropwise, the reaction continues for 2-4 hours after the dropwise addition is completed, then the reaction solution is cooled, filtered and distilled to obtain 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether; The catalyst is a solid base catalyst, and the preparation method is: S1: 100-140 parts of dry base quaternary ammonium salt type anion exchange resin, 30-50 parts of acryloyl chloride, 500-1000 parts of dichloroethane and 10-20 parts of zinc chloride are weighed into a stirring reaction kettle, and stirred at 20-30°C for 10-16 hours to obtain a propenyl quaternary ammonium salt type anion exchange resin; S2: 15-30 parts of 2,5-dimercaptothiazole, 0.005-0.05 parts of a methacryl cage type silsesquioxane, 0.5-2.5 parts of an allyl amine salt, and 1-3 parts of an ionic liquid catalyst are added into a sealed high-pressure reaction kettle, heated to 70-80°C and reacted for 40-90 minutes, filtered and dried to obtain an intermediate 1; S3: The intermediate 1 is placed in a glass exchange house, which accounts for 20-30% of the volume of the exchange house, water is added to cover the surface of the resin, then sodium hydroxide with a mass percentage content of 10-20% is added at a flow rate of 0.5-2 BV / h, the column is added dropwise, filtered and dried to obtain a solid base catalyst.

2. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that: The organic solvent is selected from one of acetonitrile, sulfolane, dimethyl sulfoxide, tetrahydrofuran, methyl tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, methyl tert-butyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, and cyclohexanone.

3. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that, The stirring speed is 80-120 rpm.

4. The process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimers, characterized in that: The reaction temperature is 45-60°C.

5. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that: The ratio of deionized water to catalyst is 1:4-8.

6. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that: The dropwise addition time of the mixture of deionized water and catalyst is 2-4 hours.

7. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that: The dry base quaternary ammonium salt type anion exchange resin is selected from D201 and 717 resin, and the factory type is quaternary ammonium salt type.

8. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that: The allyl amine salt is selected from allyl amine hydrochloride or diallyl amine hydrochloride, which is dried before use to remove water.

9. A process according to claim 1 for the preparation of 1-(hexafluoroisopropyl) perfluoropropyl-2,2-difluoroethyl ether from hexafluoropropene dimer, characterized in that: The ionic liquid catalyst is selected from any one of [Bmim]OH, [Emim]OH, [Hmim]OH and [Omim]OH.