Fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst and preparation method thereof, and preparation method of tert-butyl (meth) acrylate

Abstract

The invention provides a preparation method of a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst and a preparation method of tert-butyl (meth) acrylate, and the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is a solid catalyst capable of catalyzing an acid-olefin addition reaction of (meth) acrylic acid and isobutene. According to the present invention, the catalyst has the advantages of simple preparation process, low swelling rate in the isobutylene system, low selectivity of the byproduct diisobutylene and triisobutylene when the catalyst is used in the preparation of the tert-butyl (meth) acrylate, continuous production operation of the tert-butyl (meth) acrylate, and high reaction selectivity of the product.

Description

Technical Field

[0001] The invention belongs to the field of organic compound preparation, and specifically relates to a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst and a preparation method thereof, and a preparation method of tert-butyl (meth)acrylate. Background Art

[0002] Tert-butyl (meth)acrylate, referred to as Tert-B(M)A. Tert-butyl (meth)acrylate is an important organic synthetic raw material, widely used in coatings, inks, adhesives, plastics, resins and other fields, with broad application prospects and market demand.

[0003] At present, the industrial production method of tert-butyl (meth)acrylate mainly adopts the reaction synthesis of (meth)acrylic acid and isobutylene under acidic catalyst conditions.

[0004] Patent CN202210076468.3 discloses a method for synthesizing tert-butyl (meth)acrylate, in which (meth)acrylic acid and isobutylene are reacted in the presence of an inhibitor and a catalyst to prepare tert-butyl (meth)acrylate. The catalyst used is a macroporous strongly acidic cation exchange resin polymerized with styrene and divinylbenzene as the main monomer raw materials. However, the selectivity of the by-products diisobutylene and triisobutylene in this method is relatively high, and the selectivity of the product tert-butyl acrylate is low, only 94.9%.

[0005] Patent CN202211477485.4 discloses a process for preparing tert-butyl (meth)acrylate, wherein tert-butyl (meth)acrylate is synthesized by adding (meth)acrylic acid, a catalyst, an inhibitor, isobutylene and an inert substance into a reactor; the catalyst is one or more of an acidic cationic resin, p-toluenesulfonic acid and nafion, but an intermittent reaction process is used in the scheme, and the selectivity of tert-butyl acrylate is up to 98.6%, and the yield is low.

[0006] Patent CN201310041364.X discloses a preparation process for synthesizing tert-butyl acrylate using a strong acid cation exchange resin as a catalyst, wherein acrylic acid, a strong acid cation exchange resin, an inhibitor A, and an inhibitor B are added to a closed reactor, and liquefied isobutylene is added dropwise for esterification reaction; after the addition is completed, the reaction is kept warm; after the heat preservation is completed, the closed reactor is depressurized, filtered, and the liquid component is extracted into a distillation tower; by-product tert-butyl alcohol, diisobutylene, and the target product tert-butyl acrylate are separated in sequence. In this example, an intermittent reaction process is used.

[0007] Patent CN201911266958.4 discloses a process for synthesizing tert-butyl acrylate, which uses acrylic acid and isobutylene as raw materials, p-toluenesulfonic acid as a catalyst, and performs an acid-ene addition reaction in a microchannel reactor. The reaction solution is separated to obtain tert-butyl acrylate product. The process uses a microchannel reactor, which is suitable for the highly exothermic reaction of acid-ene addition, and improves the reaction conversion rate and product selectivity. However, the selectivity of tert-butyl acrylate needs to be further improved.

[0008] Based on the problem that the traditional direct acid-olefin addition process of (meth)acrylic acid and isobutylene to prepare tert-butyl (meth)acrylate has high selectivity for diisobutylene and triisobutylene as by-products and low selectivity for the product, it is urgent to develop a new catalyst and a method for preparing tert-butyl (meth)acrylate to achieve high selectivity for the tert-butyl (meth)acrylate product and continuous and stable operation. Summary of the invention

[0009] In order to solve the above problems, the present invention provides a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst and a preparation method thereof and a method for preparing tert-butyl (meth)acrylate. The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst of the present invention can be used to catalyze the acid-ene addition reaction of (meth)acrylic acid and isobutylene, and has a low swelling rate in an isobutylene system. When the catalyst is used in the preparation of tert-butyl (meth)acrylate, the selectivity of by-products diisobutylene and triisobutylene is low, and the continuous production operation of tert-butyl (meth)acrylate can be realized with high product selectivity.

[0010] In order to achieve the above invention object, the technical solution adopted by the present invention is as follows:

[0011] The present invention provides a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst having at least one of the following structural formulas:

[0012]

[0013] The values ​​of m and n are independently 5 to 50, preferably 10 to 40;

[0014] In the present invention, the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst preferably has the following structure:

[0015]

[0016] In the present invention, the number average molecular weight of the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is 5000-7000.

[0017] In the present invention, the fluorine content in the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is 40-50wt%.

[0018] In the present invention, the phosphorus content of the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is 6 to 12 wt%.

[0019] The present invention also provides a method for preparing the above-mentioned fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst, comprising the following steps:

[0020] (1) para-chlorostyrene and perfluoroolefin undergo polymerization reaction to prepare copolymer white balls;

[0021] (2) adding an alkyl phosphite to the copolymer white balls obtained in step (1) to carry out a phosphonylation reaction to obtain a phosphonylation product;

[0022] (3) The phosphonylated product obtained in step (2) is hydrolyzed in phosphoric acid to obtain a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst.

[0023] The styrene units and perfluoroolefin units in the catalyst are randomly copolymerized.

[0024] In step (1) of the present invention, the polymerization reaction is carried out at a temperature of 60 to 130° C., preferably 85 to 105° C., for a time of 3 to 14 hours, preferably 8 to 9 hours, and at a pressure of 2 to 7 MPaG, preferably 3 to 4 MPaG. After the reaction is completed, the pressure is released to normal pressure.

[0025] The molar ratio of the perfluoroolefin to p-chlorostyrene is 1 to 4:1, preferably 2 to 3:1.

[0026] The perfluoroolefin is at least one of tetrafluoroethylene and / or hexafluoropropylene, preferably tetrafluoroethylene.

[0027] In step (1), an initiator is also added, and the initiator is selected from peroxide or azo initiator.

[0028] Preferably, after the completion of the polymerization reaction, a post-treatment process such as preparing oil beads is also included. The known techniques in the art can be used, such as adding pure water and gelatin methylene blue solution to a reaction kettle, heating to 60-100° C. and then dripping the oil phase obtained after the polymerization reaction for 4-12 hours, cooling and filtering to obtain beads, and washing and drying to obtain copolymer white balls.

[0029] In step (2) of the present invention, the phosphonylation reaction is carried out at a temperature of 130 to 180° C., preferably 150 to 170° C., and for a time of 5 to 15 hours, preferably 8 to 10 hours.

[0030] In the phosphonylation reaction, the alkyl phosphite is at least one of trimethyl phosphite, triethyl phosphite and tributyl phosphite, preferably triethyl phosphite.

[0031] In the phosphonylation reaction, the mass ratio of the alkyl phosphite to the copolymer white ball is 1 to 8:1, preferably 4 to 5:1.

[0032] In the phosphonylation reaction, the solvent is at least one of propylene glycol methyl ether acetate, N,N-dimethylacetamide, and ethylene glycol mono-tert-butyl ether, preferably N,N-dimethylacetamide.

[0033] In the phosphonylation reaction, the mass ratio of the solvent to the copolymer white balls is 1 to 7:1, preferably 3 to 4:1.

[0034] Preferably, after the phosphonylation reaction is completed, a post-treatment process such as preparation, washing, and filtration is also included.

[0035] In step (3) of the present invention, the hydrolysis reaction temperature is 50 to 110° C., preferably 70 to 90° C., and the time is 4 to 16 hours, preferably 8 to 12 hours.

[0036] In step (3), the phosphoric acid is preferably concentrated phosphoric acid having a concentration of 80 to 85 wt %.

[0037] In step (3), the mass ratio of concentrated phosphoric acid to the phosphonylated product is 2 to 7:1, preferably 4 to 5:1.

[0038] Preferably, after the hydrolysis reaction is completed, it also includes post-treatment processes such as preparation, washing, filtering, and drying.

[0039] The present invention also provides a method for preparing tert-butyl (meth)acrylate. (meth)acrylic acid and isobutylene undergo an acid-ene addition reaction under the condition of the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst of the present invention.

[0040] In the present invention, a segmented fixed bed tubular reactor is adopted and isobutylene is fed in segments.

[0041] The present invention adopts a segmented fixed bed tubular reactor, preferably a fixed bed tubular reactor with more than three segments, more preferably a fixed bed tubular reactor with upper, middle and lower segments. Isobutylene is fed from the upper, middle and lower segments respectively, which can further reduce the generation of by-product diisobutylene and triisobutylene and reduce the unit consumption of isobutylene.

[0042] In the present invention, the concentration of isobutylene in the fixed bed tubular reactor can be controlled by controlling the staged feeding method, so that the isobutylene concentration inside the fixed bed tubular reactor is low, and the selectivity of by-product diisobutylene and triisobutylene is increased due to excessive isobutylene concentration.

[0043] In the present invention, the reactor is filled with a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst.

[0044] In the present invention, in order to better achieve uniform distribution of reaction heat in the segmented fixed bed tubular reactor, warm water is used for heat exchange, and the temperature of the warm water is 20 to 40°C, preferably 25 to 35°C.

[0045] In the present invention, a polymerization inhibitor is also added to the reaction, and the polymerization inhibitor is at least one of ZJ-701, ZJ-705, ZJ-706 and ZJ-709, preferably ZJ-706;

[0046] In the present invention, the mass ratio of the polymerization inhibitor to (meth)acrylic acid is 0.0001 to 0.005:1, preferably 0.001 to 0.002:1.

[0047] In the present invention, the molar ratio of isobutylene to (meth)acrylic acid is 1.0 to 2:1, preferably 1.1 to 1.2:1.

[0048] In the present invention, the feed volume space velocity of the mixed material is 0.3 to 3 h -1 , preferably 0.8 to 1.5 hours -1 ; and / or the reaction hot spot temperature is 20 to 50°C, preferably 30 to 40°C; the reaction pressure is 0.4 to 1.0 MPaG, preferably 0.6 to 0.7 MPaG.

[0049] In the present invention, compressed nitrogen needs to be continuously introduced during the reaction process, and the compressed nitrogen can maintain the pressure of the reaction system; preferably, the maximum pressure of the compressed nitrogen required to supplement the system pressure is 0.4-1.0 MPaG, more preferably 0.6-0.7 MPaG.

[0050] The technical solution of the present invention has the beneficial effects of:

[0051] A fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is used, the catalyst activity is moderate, the main reaction is selectively catalyzed, the by-product diisobutylene and triisobutylene are low in selectivity, the reaction conditions are mild, and the selectivity of the (methyl) tert-butyl ester prepared by continuous production is as high as more than 99%, and the conversion rate of (methyl) acrylic acid is as high as more than 99.9%.

[0052] The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst used contains fluorine element, has good swelling resistance to the reaction liquid containing isobutylene system, high strength, is not easy to be crushed and powdered under high pressure, and prolongs the service life of the catalyst.

[0053] A segmented fixed-bed tubular reactor is used, and isobutylene is fed in segments, so that the isobutylene concentration in the reactor is uniform, thereby avoiding the increase in by-product selectivity caused by high local isobutylene concentration.

[0054] The whole process has high atom economy, no catalyst waste liquid, little three wastes, is environmentally friendly, and can be used for large-scale continuous production of tert-butyl (meth)acrylate. DETAILED DESCRIPTION

[0055] The present invention is further described below by way of examples, which are not limited to the following examples. The present invention extends to any new features or any new combination disclosed in the specification, and any new method or process steps or any new combination disclosed.

[0056] 1. Sources of main raw materials in the examples:

[0057] 1. Parachlorostyrene, Hubei Xingyan New Materials Technology Co., Ltd., analytical grade;

[0058] 2. Hexafluoropropylene, Dalian Datai Gas Co., Ltd., analytical grade;

[0059] 3. Tetrafluoroethylene, Dalian Datai Gas Co., Ltd., analytical grade;

[0060] 4. Triethyl phosphite, from Handan Congtai Xinyuansheng Chemical Co., Ltd., analytical grade;

[0061] 5. N,N-dimethylacetamide, Beijing Inokai Technology Co., Ltd., analytical grade;

[0062] 6. 85% concentrated phosphoric acid, Beijing Inokai Technology Co., Ltd., analytical grade;

[0063] 7. Acrylic acid, Wanhua Chemical Group Co., Ltd., industrial grade;

[0064] 8. Methacrylic acid, Wanhua Chemical Group Co., Ltd., industrial grade;

[0065] 9. Isobutylene, Dalian Data Gas Co., Ltd., analytical grade;

[0066] 10. 706 inhibitor, Jiangsu Bosite Chemical Technology Co., Ltd., industrial grade;

[0067] 2. Product analysis method in the embodiment:

[0068] The molecular weight of the catalyst was determined by gel chromatography (GPC), instrument manufacturer and model: Shimadzu (Japan) LC-20AD;

[0069] Physical adsorption instrument was used to determine the BET value of the catalyst. Instrument manufacturer and model: MICROMERITICS (USA) ASAP2020;

[0070] The gas chromatography analysis used the correction factor method, instrument manufacturer and model: Shimadzu 1020-plus.

[0071] X-ray fluorescence spectrometer (XRF) was used to determine the fluorine content of the catalyst. Instrument manufacturer and model: PANalytical (Netherlands) Axios mAX;

[0072] Embodiment 1:

[0073] The steps of preparing a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst are as follows:

[0074] (1) Tetrafluoroethylene (8 kg) and p-chlorostyrene (5.54 kg) were added to a 50 L batching kettle at a ratio of 2:1 (mol) and mixed evenly. 0.6 wt% tert-butyl hydroperoxide (81.24 g (based on the total amount)) was added and the temperature was raised to 85° C. While nitrogen was introduced to control the reaction pressure to 3 MPaG, an oil phase was prepared. 16 kg of pure water, 0.8 kg of gelatin and an appropriate amount of 0.04 kg of methylene blue solution were added to the reactor. The temperature was raised to 85° C. and the oil phase was added dropwise to react for 8 h. The temperature was lowered to 20° C. and then filtered to obtain beads. The copolymer was washed with 72 kg of dichloromethane and filtered and dried to obtain white balls.

[0075] (2) 6 kg of N,N-dimethylacetamide and 2 kg of copolymer white balls obtained in step 1) were mixed at a ratio of 3:1 (mass ratio), the temperature was raised to 150° C., 8 kg of triethyl phosphite was added dropwise for 4 h, and the beads were aged for 4 h after the addition was completed. The beads were cooled to 20° C. and filtered to obtain beads. The beads were washed with 10 kg of dichloromethane, filtered, and dried to obtain the phosphonylated product.

[0076] (3) 8 kg of 85 wt% concentrated phosphoric acid was mixed with the phosphonylated product obtained in step 2) at a ratio of 4:1 (mass ratio), the temperature was raised to 70° C., the reaction was continued for 8 h, the temperature was lowered to 20° C., and the mixture was filtered. The mixture was washed with 10 kg of dichloromethane, filtered, and dried to obtain a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst.

[0077] The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst prepared in Example 1 has a molecular weight of about 5610 (Mn), a fluorine content of 40.6%, a phosphorus content of 8.3%, and a swelling ratio of 3.3% in isobutylene.

[0078] Embodiment 2:

[0079] The steps of preparing a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst are as follows:

[0080] (1) Tetrafluoroethylene (6 kg) and p-chlorostyrene (2.77 kg) were added to a 50 L batching kettle at a ratio of 2:1 (mol) and mixed evenly, 0.6 wt% tert-butyl hydroperoxide (52.62 g (based on the total amount)) was added, and the temperature was raised to 105° C., while nitrogen was introduced to control the reaction pressure to 4 MPaG to prepare an oil phase; 12 kg of pure water, 0.6 kg of gelatin and 0.03 kg of methylene blue solution were added to the reactor, the temperature was raised to 105° C., the oil phase was added dropwise, and the reaction was carried out for 9 hours, the temperature was lowered to 20° C., and then the beads were filtered to obtain beads, which were washed with 54 kg of dichloromethane, filtered and dried to obtain copolymer white balls;

[0081] (2) 8 kg of N,N-dimethylacetamide and the copolymer white balls obtained in step 1) were mixed at a ratio of 4:1 (mass ratio), the temperature was raised to 170°C, 10 kg of triethyl phosphite was added dropwise for 4 hours, and the mixture was aged for 4 hours after the addition was completed. The mixture was cooled to 20°C and filtered to obtain beads, which were washed with 10 kg of dichloromethane, filtered and dried to obtain the phosphonylated product.

[0082] (3) 10 kg of 85 wt% concentrated phosphoric acid and the phosphonylated product obtained in step 2) were mixed at a ratio of 5:1 (mass ratio), the temperature was raised to 90° C., the reaction was continued for 12 h, the temperature was lowered to 20° C., and the mixture was filtered. The mixture was washed with 10 kg of dichloromethane, filtered, and dried to obtain a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst.

[0083] The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst prepared in Example 2 has a molecular weight of about 6889 (Mn), a fluorine content of 48.1%, a phosphorus content of 6.5%, and a swelling ratio of 2.9% in isobutylene.

[0084] Embodiments 3 to 7

[0085] The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst prepared in Example 1 was loaded into a three-stage fixed-bed tubular reactor with a jacket. First, 706 polymerization inhibitor was added to acrylic acid to prepare an acrylic acid solution. Isobutylene and acrylic acid solution were added to the fixed-bed reactor in a certain proportion, wherein isobutylene was divided into three parts and respectively entered the upper, middle and lower feed ports of the reactor. The system controlled the reaction pressure to 0.6 MPaG by adding depleted oxygen, and the reaction hot spot temperature was controlled to 30° C. by adjusting the jacket warm water temperature. The raw material ratio of isobutylene and acrylic acid in the raw material mixture was changed. The specific reaction process conditions and reaction results of Examples 3 to 7 are shown in Table 1.

[0086] Table 1

[0087]

[0088]

[0089] Example 3 was stably operated for 2000 h, the acrylic acid conversion rate was stabilized at 99.0% and above, the selectivity of tert-butyl acrylate was maintained at above 99.0%, and the sum of the selectivities of by-product diisobutylene and triisobutylene was less than 1%.

[0090] Embodiments 8 to 10

[0091] The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst prepared in Example 2 was loaded into a three-stage fixed-bed tubular reactor with a jacket. First, 706 polymerization inhibitor was added to acrylic acid to prepare an acrylic acid solution. Isobutylene and acrylic acid solution were added to the fixed-bed reactor in a certain proportion, wherein isobutylene was divided into three parts and respectively entered the upper, middle and lower feed ports of the reactor. The system controlled the reaction pressure to 0.7 MPaG by adding depleted oxygen, and the reaction hot spot temperature was controlled to 50° C. by adjusting the jacket warm water temperature. The raw material ratio of isobutylene and acrylic acid in the raw material mixture was changed. The specific reaction process conditions and reaction results of Examples 8 to 10 are detailed in Table 2.

[0092] Table 2

[0093]

[0094] Example 8 was stably operated for 3000 h, the acrylic acid conversion rate was stabilized at 99.0% and above, the selectivity of tert-butyl acrylate was maintained at above 99.0%, and the sum of the selectivities of by-product diisobutylene and triisobutylene was less than 1%.

[0095] Embodiment 11

[0096] The fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst prepared in Example 2 was loaded into a three-stage fixed-bed tubular reactor with a jacket. First, 706 polymerization inhibitor was added to methacrylic acid to prepare a methacrylic acid solution. Isobutylene and methacrylic acid solution were added to the fixed-bed reactor in a certain proportion, wherein isobutylene was divided into three parts and respectively entered the upper, middle and lower feed ports of the reactor. The system controlled the reaction pressure to 0.7 MPaG by adding depleted oxygen, and the reaction hot spot temperature was controlled to 50° C. by adjusting the jacket warm water temperature. The raw material ratio of isobutylene and acrylic acid in the raw material mixture was changed. The specific reaction process conditions and reaction results of Examples 13 to 17 are shown in Table 3.

[0097] Table 3

[0098]

[0099] Example 11 was stably operated for 2000 h, the methacrylic acid conversion rate was stabilized at 98.0% and above, the selectivity of tert-butyl methacrylate was maintained at above 99.0%, and the sum of the selectivities of by-product diisobutylene and triisobutylene was less than 1%.

[0100] It can be seen from the data in Tables 1, 2 and 3 above that by loading the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst, under the optimal reaction process conditions, the (meth)acrylic acid conversion rate can reach more than 98%, the selectivity of tert-butyl (meth)acrylate can reach more than 99.0%, and no catalyst blockage was found in the reactor after operating for more than 2000 hours.

[0101] Example 12

[0102] The difference from Example 3 is that the fixed bed reactor adopts a non-segmented type and a single isobutylene feed position. After stable operation under the same other conditions, the acrylic acid conversion rate is 99.09%, but the selectivity of tert-butyl acrylate is 96.8%, and the sum of the selectivity of by-product diisobutylene and triisobutylene is 3.2%.

[0103] Comparative Example 1

[0104] The difference from Example 3 is that: a purchased strongly acidic cation exchange resin (brand A36, Dow Chemical (Shanghai) Co., Ltd.) is used. After stable operation under the same conditions, the acrylic acid conversion rate is 99.0%, but the selectivity of tert-butyl acrylate is 92.1%, and the sum of the selectivity of by-product diisobutylene and triisobutylene is 7.9%, which affects the product yield.

Claims

1. A fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst, characterized in that: Has at least one of the following structural formulas: The values ​​of m and n are independently 5 to 50, preferably 10 to 40.

2. The catalyst according to claim 1, characterized in that The structure of the catalyst is: Wherein, m and n have the same meaning as in claim 1.

3. The catalyst according to claim 1 or 2, characterized in that The number average molecular weight of the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is 5000 to 7000; Preferably, the fluorine content in the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is 40 to 50 wt%; Preferably, the phosphorus content of the fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst is 6 to 12 wt %.

4. The method for preparing the catalyst according to any one of claims 1 to 3, characterized in that: The steps include: (1) para-chlorostyrene and perfluoroolefin undergo polymerization reaction to prepare copolymer white balls; (2) adding an alkyl phosphite to the copolymer white balls obtained in step (1) to carry out a phosphonylation reaction to obtain a phosphonylation product; (3) The phosphonylated product obtained in step (2) is hydrolyzed in phosphoric acid to obtain a fluorine-containing phosphonic acid type weakly acidic cationic resin catalyst.

5. The preparation method according to claim 4, characterized in that: In step (1), the polymerization reaction temperature is 60°C to 130°C, preferably 85°C to 105°C, the reaction time is 3 to 14 hours, preferably 8 to 9 hours, the reaction pressure is 2 to 7 MPaG, preferably 3 to 4 MPaG, and the pressure is released to normal pressure after the reaction is completed; Preferably, the molar ratio of the perfluoroolefin to p-chlorostyrene is 1 to 4:1, preferably 2 to 3:1; Preferably, the perfluoroolefin is at least one of tetrafluoroethylene and / or hexafluoropropylene, preferably tetrafluoroethylene; Preferably, an initiator is also added in step (1), and the initiator is selected from peroxide or azo initiator.

6. The preparation method according to claim 4 or 5, characterized in that: In step (2), the phosphonylation reaction temperature is 130 to 180° C., preferably 150 to 170° C., and the reaction time is 5 to 15 hours, preferably 8 to 10 hours; Preferably, the alkyl phosphite is at least one of trimethyl phosphite, triethyl phosphite and tributyl phosphite, preferably triethyl phosphite; Preferably, the mass ratio of the alkyl phosphite to the copolymer white ball is 1 to 8:1, preferably 4 to 5:1; Preferably, the phosphonylation reaction is carried out in a solvent, and the solvent is at least one of propylene glycol methyl ether acetate, N,N-dimethylacetamide, and ethylene glycol mono-tert-butyl ether, preferably N,N-dimethylacetamide; Preferably, in the phosphonylation reaction, the mass ratio of the solvent to the copolymer white balls is 1 to 7:1, preferably 3 to 4:

1.

7. The preparation method according to any one of claims 4 to 6, characterized in that: In step (3), the hydrolysis reaction temperature is 50 to 110° C., preferably 70 to 90° C., and the time is 4 to 16 hours, preferably 8 to 12 hours; Preferably, in step (3), the phosphoric acid is preferably concentrated phosphoric acid with a concentration of 80 to 85 wt %; Preferably, in step (3), the mass ratio of concentrated phosphoric acid to the phosphonylated product is 2 to 7:1, preferably 4 to 5:

1.

8. A method for preparing tert-butyl (meth)acrylate, comprising carrying out an acid-ene addition reaction between (meth)acrylic acid and isobutylene in the presence of a catalyst according to any one of claims 1 to 3 or a catalyst prepared by the preparation method according to any one of claims 4 to 7.

9. The preparation method according to claim 8, characterized in that: The reactor adopts a segmented fixed bed tubular reactor, and isobutylene is fed in segments; Preferably, the reactor is a fixed bed tubular reactor with three or more sections, more preferably a fixed bed tubular reactor with three sections, and isobutylene is fed from the upper, middle and lower sections respectively.

10. The preparation method according to claim 8 or 9, characterized in that: A polymerization inhibitor is also added during the reaction, wherein the polymerization inhibitor is at least one of ZJ-701, ZJ-705, ZJ-706 and ZJ-709, preferably ZJ-706; Preferably, the mass ratio of the polymerization inhibitor to (meth)acrylic acid is 0.0001 to 0.005:1, preferably 0.001 to 0.002:1; Preferably, the molar ratio of isobutylene to (meth)acrylic acid is 1.0 to 2:1, preferably 1.1 to 1.2:1; Preferably, the feed volume space velocity of the mixed material is 0.3 to 3 h -1 , preferably 0.8 to 1.5 hours -1 ; Preferably, the reaction hot spot temperature is 20 to 50° C., preferably 30 to 40° C.; the reaction pressure is 0.4 to 1.0 MPaG, preferably 0.6 to 0.7 MPaG.

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