Method for producing (meth) acrylate having vinyl ether group

Abstract

A method for producing a (meth) acrylate having a vinyl ether group. [Problem] To provide a method for sufficiently preventing polymerization of a liquid phase part when a (meth) acrylate having a vinyl ether group is produced by a transesterification reaction. [Solution] The present invention is a method for producing a (meth) acrylate having a vinyl ether group, characterized by comprising a step for obtaining a (meth) acrylate having a vinyl ether group by transesterification using a starting material solution containing a starting material (meth) acrylate, a hydroxyl group-containing vinyl ether compound, and a catalyst, the starting material solution further contains a prescribed phenolic antioxidant and a phosphite ester, and in the starting material solution, the mass ratio of the prescribed phenolic antioxidant is 0.2% by mass or more and the mass ratio of the phosphite ester is 0.2% by mass or more.

Description

Technical Field

[0001] The present invention relates to a method for producing a (meth)acrylate having a vinyl ether group. More specifically, the present invention relates to a method for producing a (meth)acrylate having a vinyl ether group which is used as a raw material for various industrial products. Background Art

[0002] (Meth)acrylates having a vinyl ether group are easily polymerizable compounds having a (meth)acryloyl group containing a free radical polymerizable double bond and being able to be easily polymerized using heat, light, ultraviolet rays, etc. Therefore, they are very useful as monomers for polymers, and various methods for producing them have been studied. As one of the reaction processes, a process for producing (meth)acrylates having a vinyl ether group by causing a raw material (meth)acrylate to undergo an ester exchange reaction with a hydroxyl-containing vinyl ether compound is known. In this reaction process, since both the raw material and the target product are easily polymerizable compounds, various methods for preventing them from polymerizing have been studied.

[0003] For example, the following production method is disclosed, which is characterized in that it is a method for producing a (meth)acrylate having an ether group from a reaction raw material containing a (meth)acrylate and a hydroxyl-containing ether compound, and the production method includes the following steps: reacting the reaction raw material in the presence of a specific N-nitrosophenylhydroxylamine salt, a phosphite and / or a thioether, and a primary antioxidant (for example, refer to Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2012-197236 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] However, when a (meth)acrylate having a vinyl ether group is produced in the presence of a catalyst, the polymerization stability of the liquid phase of the reaction system becomes low. There is still room for further improvement in terms of fully preventing the polymerization of the liquid phase.

[0009] The present invention has been made in view of the above-mentioned current situation, and an object of the present invention is to provide a method for sufficiently preventing polymerization in a liquid phase when producing a (meth)acrylate having a vinyl ether group by an ester exchange reaction.

[0010] Solutions for solving problems

[0011] The present inventors have conducted various studies on methods for sufficiently preventing polymerization of the liquid phase when producing (meth)acrylates having a vinyl ether group by transesterification reaction, and focused on the formulation used. The present inventors have found that polymerization of the liquid phase can be sufficiently prevented when producing (meth)acrylates having a vinyl ether group by making the raw material solution contain the raw material (meth)acrylate, the hydroxyl-containing vinyl ether compound and the catalyst, and contain 0.2% by mass or more of a prescribed phenolic antioxidant and a phosphite, respectively, and have found that the above-mentioned problems can be perfectly solved, thereby completing the present invention.

[0012] That is, the present invention (1) is a method for producing a (meth)acrylate having a vinyl ether group, characterized in that it includes the following steps: using a raw material solution containing a raw material (meth)acrylate, a hydroxyl-containing vinyl ether compound and a catalyst, to obtain a (meth)acrylate having a vinyl ether group by an ester exchange reaction, the raw material solution also containing a compound represented by the following formula (1) and a phosphite, and in the raw material solution, the mass ratio of the compound represented by the following formula (1) is 0.2 mass% or more, and the mass ratio of the phosphite is 0.2 mass% or more.

[0013]

[0014] In the above formula, R 1 ~R 4 are the same or different and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms. m, n, p, and q are the same or different and represent an integer of 1 to 4.

[0015] The present invention (2) is a method for producing a (meth)acrylate having a vinyl ether group according to the present invention (1), characterized in that the above-mentioned hydroxyl-containing vinyl ether compound is diethylene glycol monovinyl ether, and the above-mentioned (meth)acrylate having a vinyl ether group is 2-(2-vinyloxyethoxy)ethyl (meth)acrylate.

[0016] Effects of the Invention

[0017] The method for producing a (meth)acrylate having a vinyl ether group of the present invention includes the above-mentioned configuration, and can sufficiently prevent the polymerization of the (meth)acryloyl group in the liquid phase. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram showing an example of a production apparatus for carrying out the production method of the present invention.

[0019] Description of Reference Numerals

[0020] 1: Raw material solution

[0021] 2: Waste oil

[0022] 3: Finished product (rough product)

[0023] 11: Reaction tank

[0024] 21: First distillation tower

[0025] 31: Second distillation column

[0026] 71, 72, 81: Pipeline DETAILED DESCRIPTION

[0027] The present invention is described in detail below.

[0028] In addition, the preferred aspects of the present invention described below may be combined with two or more of the preferred aspects of the present invention.

[0029] <Step of Obtaining (Meth) Acrylic Acid Ester Having Vinyl Ether Group>

[0030] The manufacturing method of the present invention comprises the following steps: using a raw material solution comprising a raw material (meth) acrylic acid ester, a hydroxyl-containing vinyl ether compound and a catalyst, obtaining a (meth) acrylic acid ester having a vinyl ether group by an ester exchange reaction, wherein the raw material solution further comprises a compound represented by the above formula (1) and a phosphite, wherein in the raw material solution, the mass ratio of the compound represented by the above formula (1) is 0.2 mass % or more, and the mass ratio of the phosphite is 0.2 mass % or more. In this specification, the step of obtaining a (meth) acrylic acid ester having a vinyl ether group by an ester exchange reaction is also referred to as a reaction step.

[0031] In addition, in this specification, (meth)acrylate means acrylate and / or methacrylate, and (meth)acryloyl means acryloyl and / or methacryloyl.

[0032] (Compound represented by formula (1))

[0033] In the manufacturing method of the present invention, the raw material solution contains 0.2% by mass or more of the compound represented by the above formula (1). By making the raw material solution contain 0.2% by mass or more of the compound represented by the above formula (1) and 0.2% by mass or more of the phosphite described later, these compounds can synergistically play a role as an anti-polymerization agent and fully prevent polymerization in the liquid phase.

[0034] In the above formula, R 1 ~R 4 are the same or different and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms. 1 ~R 4 In the formula (a), at least one of the above hydrocarbon groups is preferred, at least two of the above hydrocarbon groups are preferred, at least three of the above hydrocarbon groups are further preferred, and R is particularly preferred. 1 ~R 4All represent the hydrocarbon group.

[0035] Examples of the hydrocarbon group having 1 to 5 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, and a pentyl group.

[0036] The number of carbon atoms in the hydrocarbon group having 1 to 5 carbon atoms is preferably 2 to 5, more preferably 3 to 5, further preferably 4 or 5, and further preferably 4. The hydrocarbon group having 1 to 5 carbon atoms is particularly preferably a tert-butyl group.

[0037] m, n, p, and q are the same or different and are integers of 1 to 4. m, n, p, and q are preferably integers of 1 to 3, more preferably 1 or 2, and even more preferably 2.

[0038] The mass ratio of the compound represented by the above formula (1) in the raw material solution is preferably 0.3 mass % or more, more preferably 0.4 mass % or more. From the viewpoint of further preventing the effect from being saturated, the mass ratio is preferably 5 mass % or less, more preferably 3 mass % or less, and further preferably 1 mass % or less.

[0039] In this specification, the mass ratio in the raw material solution refers to the mass ratio in the raw material solution immediately before being supplied to the reaction step. The raw material solution may be put into a reaction device such as a reaction tank at once, or may be supplied to the reaction device continuously or intermittently.

[0040] (Phosphite)

[0041] In the production method of the present invention, the raw material solution contains 0.2 mass % or more of the phosphite.

[0042] The phosphite ester acts as a secondary antioxidant in the reaction step of the present invention to decompose peroxides gradually generated in the liquid phase of the reaction system to suppress the polymerization reaction associated with the peroxides.

[0043] As the above-mentioned phosphite, specifically, triphenyl phosphite (TPP), tris (2,4-di-tert-butylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite (BPOP), diphenyl mono (tridecyl) phosphite, diphenyl monodecyl phosphite, dioctadecyl pentaerythritol diphosphite, trioleyl phosphite, etc. can be listed, and one or more of these can be used. Among these, TPP, tris (2,4-di-tert-butylphenyl) phosphite, BPOP, diphenyl mono (tridecyl) phosphite, diphenyl monodecyl phosphite are preferred, and TPP, tris (2,4-di-tert-butylphenyl) phosphite, BPOP are more preferred. TPP and tris (2,4-di-tert-butylphenyl) phosphite are further preferred, and tris (2,4-di-tert-butylphenyl) phosphite is particularly preferred.

[0044] The mass ratio of the above-mentioned phosphite in the raw material solution is preferably 0.3 mass % or more, more preferably 0.4 mass % or more. From the viewpoint of further preventing the effect from being saturated, the mass ratio is preferably 5 mass % or less, more preferably 3 mass % or less, and further preferably 1 mass % or less.

[0045] (Raw material (meth)acrylate)

[0046] The raw material (meth)acrylate is not particularly limited as long as it can undergo an ester exchange reaction with a hydroxyl group-containing vinyl ether compound to produce a (meth)acrylate having a vinyl ether group. One or more of them may be used, and the compound represented by the following general formula (2) is preferred.

[0047] CH2=CR 1 -COO-R 3 (2)

[0048] (Where R 1 represents a hydrogen atom or a methyl group. 3 represents an organic group. )

[0049] As R in the above general formula (2) 3 The organic group shown is not particularly limited, and is preferably, for example, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or an optionally substituted aromatic group having 6 to 10 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms.

[0050] Examples of the raw material (meth)acrylate represented by the general formula (2) include lower alkyl (meth)acrylates (the alkyl group of the alkyl ester has 1 to 4 carbon atoms) such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, and tert-butyl (meth)acrylate. Among these, methyl acrylate (AM), methyl methacrylate, ethyl acrylate, and ethyl methacrylate are preferred, and methyl acrylate (AM) and ethyl acrylate are more preferred.

[0051] The raw material (meth) acrylate is preferably 10% by mass or more in 100% by mass of the raw material solution, more preferably 20% by mass or more, further preferably 30% by mass or more, further preferably 40% by mass or more, and particularly preferably 50% by mass or more. In addition, the mass ratio of the raw material (meth) acrylate is preferably 90% by mass or less, more preferably 80% by mass or less, further preferably 70% by mass or less, and particularly preferably 65% ​​by mass or less.

[0052] In addition, when two or more types of the above-mentioned raw material (meth)acrylate are used, the above-mentioned mass ratio is the mass ratio of the total.

[0053] (Hydroxy-containing vinyl ether compound)

[0054] The hydroxyl-containing vinyl ether compound is not particularly limited as long as it contains a hydroxyl group and a vinyl ether group and can undergo an ester exchange reaction with the raw material (meth)acrylate to produce a (meth)acrylate having a vinyl ether group. One or more of them can be used, among which the hydroxyl-containing vinyl ether compound represented by the following general formula (3) is preferred.

[0055] CH2=CH-OR 2 -OH (3)

[0056] (Where R 2 represents an organic group. )

[0057] In the hydroxyl-containing vinyl ether compound represented by the general formula (3), R in the general formula (3) is 2 The organic group shown is not particularly limited, and examples thereof include a linear, branched or cyclic alkylene group having 2 to 20 carbon atoms, an alkylene group having 2 to 20 carbon atoms and having an oxygen atom in the structure via an ether bond and / or an ester bond, and an optionally substituted aromatic group having 6 to 11 carbon atoms. Among these, an alkylene group having 2 to 6 carbon atoms and an alkylene group having 4 to 10 carbon atoms and having an oxygen atom in the structure via an ether bond are preferred.

[0058] Examples of the hydroxyl-containing vinyl ether compound represented by the general formula (3) include 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 2-hydroxyisopropyl vinyl ether, 4-hydroxybutyl vinyl ether, 3-hydroxybutyl vinyl ether, 2-hydroxybutyl vinyl ether, 3-hydroxyisobutyl vinyl ether, 2-hydroxyisobutyl vinyl ether, 1-methyl-3-hydroxypropyl vinyl ether, 1-methyl-2-hydroxypropyl vinyl ether, 1-hydroxymethylpropyl vinyl ether, 4-hydroxycyclohexyl vinyl ether, 1,6-hexanediol monovinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, 1,3 -cyclohexanedimethanol monovinyl ether, 1,2-cyclohexanedimethanol monovinyl ether, p-phenylenedimethanol monovinyl ether, isophenylenedimethanol monovinyl ether, o-phenylenedimethanol monovinyl ether, diethylene glycol monovinyl ether (DEGV), triethylene glycol monovinyl ether, tetraethylene glycol monovinyl ether, pentaethylene glycol monovinyl ether, oligoethylene glycol monovinyl ether, polyethylene glycol monovinyl ether, dipropylene glycol monovinyl ether, tripropylene glycol monovinyl ether, tetrapropylene glycol monovinyl ether, pentapropylene glycol monovinyl ether, oligopropylene glycol monovinyl ether, polypropylene glycol monovinyl ether, ethylene glycol-propylene glycol copolymer monovinyl ether, etc., and one or more of them can be used.

[0059] The hydroxyl-containing vinyl ether compound represented by the general formula (3) is preferably 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 2-hydroxyisopropyl vinyl ether, 4-hydroxybutyl vinyl ether, 4-hydroxycyclohexyl vinyl ether, 1,6-hexanediol monovinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, DEGV, triethylene glycol monovinyl ether, and dipropylene glycol monovinyl ether. DEGV is more preferred.

[0060] The above-mentioned hydroxyl-containing vinyl ether compound is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, further preferably 30% by mass or more, and particularly preferably 35% by mass or more in 100% by mass of the above-mentioned raw material solution. In addition, the mass proportion of the above-mentioned hydroxyl-containing vinyl ether compound is preferably 80% by mass or less, more preferably 70% by mass or less, further preferably 60% by mass or less, and particularly preferably 50% by mass or less.

[0061] In addition, when two or more hydroxyl-containing vinyl ether compounds are used, the above-mentioned mass ratio is the total mass ratio thereof.

[0062] The molar ratio of the raw material (meth) acrylic acid ester and the hydroxyl-containing vinyl ether compound in the above reaction step can be appropriately set according to the combination of the types of the raw material (meth) acrylic acid ester and the hydroxyl-containing vinyl ether compound, and is preferably 20 / 1 to 1 / 5. From the viewpoint of yield and economic efficiency, the blending ratio in this range is preferred. It is more preferably 15 / 1 to 1 / 3, and further preferably 10 / 1 to 1 / 2. It is particularly preferably 5 / 1 to 1 / 1.

[0063] (catalyst)

[0064] The above-mentioned catalyst is not particularly limited as long as it has the function of accelerating the transesterification reaction, and examples thereof include oxides such as calcium oxide, barium oxide, lead oxide, zinc oxide, and zirconium oxide; hydroxides such as potassium hydroxide, sodium hydroxide, lithium hydroxide, calcium hydroxide, thallium hydroxide, tin hydroxide, lead hydroxide, and nickel hydroxide; halides such as lithium chloride, calcium chloride, tin chloride, lead chloride, zirconium chloride, and nickel chloride; carbonates such as potassium carbonate, rubidium carbonate, cesium carbonate, lead carbonate, zinc carbonate, and nickel carbonate; hydrogen carbonates such as potassium hydrogen carbonate, rubidium hydrogen carbonate, and cesium hydrogen carbonate; phosphates such as sodium phosphate, potassium phosphate, rubidium phosphate, lead phosphate, zinc phosphate, and nickel phosphate; nitrates such as lithium nitrate, calcium nitrate, lead nitrate, zinc nitrate, and nickel nitrate; carboxylates such as lithium acetate, calcium acetate, lead acetate, zinc acetate, and nickel acetate; sodium methoxide, sodium ethoxide, potassium methoxide, and ethanol Alkoxy compounds such as potassium, potassium tert-butoxide, calcium methoxide, calcium ethoxide, barium methoxide, barium ethoxide, tetraethoxytitanium, tetrabutoxytitanium, and tetra(2-ethylhexyloxy)titanium; acetylacetonate complexes such as lithium acetylacetonate, zirconium acetylacetonate, zinc acetylacetonate, dibutoxytin acetylacetonate, and dibutoxytitanium acetylacetonate; quaternary ammonium alkoxides such as tetramethylammonium methoxide, tetramethylammonium tert-butoxide, and trimethylbenzylammonium ethoxide; dialkyltin compounds such as dimethyltin oxide, methylbutyltin oxide, dibutyltin oxide (DBTO), and dioctyltin oxide; distannoxanes such as bis(dibutyltin acetate) oxide and bis(dibutyltin laurate) oxide; and dialkyldicarboxylic acid tin salts such as dibutyltin diacetate and dibutyltin dilaurate (DBTL), and one or more of them can be used.

[0065] Among these catalysts, potassium carbonate, cesium carbonate, tetraethoxytitanium, tetrabutoxytitanium, tetra(2-ethylhexyloxy)titanium, zirconium acetylacetonate, DBTO, dioctyltin oxide, bis(dibutyltin acetate) oxide, bis(dibutyltin laurate) oxide, dibutyltin diacetate, and DBTL are preferably used. DBTO and DBTL are more preferred.

[0066] The catalyst is preferably present in an amount of 100 ppm or more, more preferably 500 ppm or more, and even more preferably 1000 ppm or more in 100% by mass of the raw material solution. In addition, the mass ratio of the catalyst is preferably 5% or less, more preferably 2% or less, and even more preferably 1% or less by mass.

[0067] In addition, when two or more of the above catalysts are used, the above mass ratio is the total mass ratio of the above catalysts.

[0068] The amount of the catalyst is not particularly limited and can be appropriately set. For example, it is preferably in the range of 0.0001 to 20 mol% relative to 100 mol% of the hydroxyl-containing vinyl ether compound. From the viewpoint of yield and economic efficiency, the amount of the catalyst is preferably in this range. It is more preferably 0.0003 to 15 mol%, further preferably 0.0005 to 10 mol%, and particularly preferably 0.001 to 5 mol%.

[0069] (Primary Antioxidant)

[0070] The above-mentioned raw material solution preferably further contains a primary antioxidant.

[0071] The primary antioxidant is not particularly limited as long as it is a primary antioxidant that can capture and decompose peroxy radicals gradually generated in the liquid phase of the reaction system in the reaction step of the present invention and inhibit the radical polymerization reaction associated with the peroxy radicals. Examples thereof include phenolic antioxidants such as hydroquinone, methoxyhydroquinone, hydroquinone monomethyl ether (MEHQ), benzoquinone, p-tert-butylcatechol, 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,4,6-tri-tert-butylphenol, 3,5-di-tert-butyl-4-hydroxytoluene (BHT), and 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane (TPB); alkylated diphenylamine, N,N'-diphenyl-p-phenylenediamine, and phenothiazine (P TZ) and other aromatic amine antioxidants; 4-hydroxy-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1,4-dihydroxy-2,2,6,6-tetramethylpiperidine, 1-hydroxy-4-benzoyloxy-2,2,6,6-tetramethylpiperidine and other cyclic amine antioxidants; copper dithiocarbamate antioxidants such as dimethyl copper dithiocarbamate, diethyl copper dithiocarbamate, and dibutyl copper dithiocarbamate; N-oxyl antioxidants such as 2,2,6,6-tetramethylpiperidine-N-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl, and esters of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl. As the primary antioxidant, among these, phenolic antioxidants and aromatic amine antioxidants are preferred. As such, an embodiment in which the primary antioxidant is a phenolic antioxidant and / or an aromatic amine antioxidant is also one of the suitable embodiments of the present invention.

[0072] As the primary antioxidant, more preferred are hydroquinone, MEHQ, 3,5-di-tert-butyl-4-hydroxytoluene, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, and PTZ.

[0073] The primary antioxidant is preferably present in an amount of 100 ppm or more, more preferably 500 ppm or more, and even more preferably 1000 ppm or more in 100% by mass of the raw material solution. In addition, the mass ratio of the primary antioxidant is preferably 2% by mass or less, more preferably 1% by mass or less, and even more preferably 5000 ppm or less.

[0074] In addition, when two or more primary antioxidants are used, the above-mentioned mass ratio is the total mass ratio thereof.

[0075] The amount of the primary antioxidant used in the reaction step of the present invention is preferably 2 ppm to 5 mass % relative to 100 mass % of the mass of the hydroxyl-containing vinyl ether compound as the reaction raw material. The amount of the primary antioxidant is preferably in this range from the viewpoint of yield, the viewpoint of inhibiting polymerization in the liquid phase of the reaction system, and the viewpoint of economic efficiency. The amount is more preferably 10 ppm to 3 mass %, further preferably 50 ppm to 1 mass %, and particularly preferably 100 ppm to 5000 ppm.

[0076] (Secondary Antioxidant)

[0077] The raw material solution contains 0.2 mass % or more of phosphite as a secondary antioxidant. The raw material solution may further contain other secondary antioxidants such as thioether.

[0078] Specific examples of the thioether include dilauryl 3,3'-thiodipropionate (TDPL), distearyl 3,3'-thiodipropionate, didodecyl 3,3'-thiodipropionate, distearyl 3,3'-thiodipropionate, and pentaerythritol tetra(β-laurylthiopropionate).

[0079] The raw material solution may further contain other secondary antioxidants such as tris(2,4-di-tert-butylphenyl)phosphite (DBPP).

[0080] The content of the other secondary antioxidant in 100% by mass of the raw material solution is preferably 2% by mass or less, more preferably 1% by mass or less, and even more preferably 5000 ppm or less.

[0081] In addition, when two or more types of the above-mentioned other secondary antioxidants are used, the above-mentioned mass ratio is the mass ratio of the total amount thereof.

[0082] In addition, the amount of the other secondary antioxidant in the raw material solution in the reaction step of the present invention is preferably 5% by mass or less relative to 100% by mass of the hydroxyl-containing vinyl ether compound as the reaction raw material. The amount is more preferably 3% by mass or less, further preferably 1% by mass or less, and particularly preferably 5000 ppm or less.

[0083] ((Meth)acrylate having a vinyl ether group)

[0084] In the production method of the present invention, a (meth)acrylate having a vinyl ether group is produced by subjecting a raw material (meth)acrylate to an ester exchange reaction with a hydroxyl-containing vinyl ether compound. Therefore, the obtained (meth)acrylate having a vinyl ether group is a compound synthesized by subjecting a compound selected from the raw material (meth)acrylate and the hydroxyl-containing vinyl ether compound to an ester exchange reaction. In this specification, the (meth)acrylate having a vinyl ether group as the target product is also referred to as a (meth)acrylate having a vinyl ether group.

[0085] In particular, when the raw material (meth)acrylate is a compound represented by general formula (2) and the hydroxyl-containing vinyl ether compound is a compound represented by general formula (3), the (meth)acrylate having a vinyl ether group can be represented by the following general formula (4).

[0086] CH2=CR 1 -COO-R 2 -O-CH=CH2 (4)

[0087] (Where R 1 represents a hydrogen atom or a methyl group. 2 represents an organic group.) In this way, an embodiment in which the (meth)acrylate having a vinyl ether group is a (meth)acrylate having a vinyl ether group represented by the general formula (4) is also one of the preferred embodiments of the present invention.

[0088] It should be noted that R in the general formula (4) 1 With R in the general formula (2) 1 Same, R in general formula (4) 2 With R in the general formula (3) 2 same.

[0089] Specific examples of the (meth)acrylate having a vinyl ether group represented by the general formula (4) include 2-vinyloxyethyl (meth)acrylate, 3-vinyloxypropyl (meth)acrylate, 1-methyl-2-vinyloxyethyl (meth)acrylate, 2-vinyloxypropyl (meth)acrylate, 4-vinyloxybutyl (meth)acrylate, 1-methyl-3-vinyloxypropyl (meth)acrylate, 1-vinyloxymethylpropyl (meth)acrylate, 2-methyl-3-vinyloxypropyl (meth)acrylate, 1,1-dimethyl-2-vinyloxyethyl ester, 3-vinyloxybutyl (meth)acrylate, 1-methyl-2-vinyloxypropyl (meth)acrylate, 2-vinyloxybutyl (meth)acrylate, 4-vinyloxycyclohexyl (meth)acrylate, 6-vinyloxyhexyl (meth)acrylate, 4-vinyloxymethylcyclohexyl methyl (meth)acrylate, 3-vinyloxymethylcyclohexyl methyl (meth)acrylate, 2-vinyloxymethylcyclohexyl methyl (meth)acrylate, p-vinyloxymethylphenyl methyl (meth)acrylate, m-vinyloxymethylphenyl methyl (meth)acrylate, o-vinyloxymethylphenyl methyl (meth)acrylate, 2-(vinyloxymethyl)phenyl methyl (meth)acrylate 2-(vinyloxyethoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyethoxy)propyl (meth)acrylate, 2-(vinyloxyethoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxy)propyl (meth)acrylate, 2-(vinyloxyisopropoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyethoxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxyethoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxyethoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyethyl)acrylate 2-(vinyloxyethoxyisopropoxy)propyl (meth)acrylate, 2-(vinyloxyisopropoxyethoxy)propyl (meth)acrylate, 2-(vinyloxyisopropoxyisopropoxy)propyl (meth)acrylate, 2-(vinyloxyethoxyethoxy)isopropyl (meth)acrylate, 2-(vinyloxyethoxyisopropoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxyethoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxyisopropoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxyethoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyethoxyethoxy) 2-(vinyloxyethoxy)ethyl acrylate, 2-(isopropoxyethoxy)ethyl (meth)acrylate, 2-(isopropoxyethoxyethoxy)ethyl (meth)acrylate, 2-(isopropoxyethoxyethoxyethoxy)ethyl (meth)acrylate, 2-(isopropoxyethoxyethoxyethoxy)ethyl (meth)acrylate, 2-(isopropoxyethoxyethoxyethoxy)ethyl (meth)acrylate, polyethylene glycol monovinyl (meth)acrylate, polypropylene glycol monovinyl (meth)acrylate, etc., among which 2-(vinyloxyethoxy)ethyl acrylate (VEEA (registered trademark)) and 2-(vinyloxyethoxy)ethyl methacrylate (VEEM (registered trademark)) are preferred, and 2-(vinyloxyethoxy)ethyl acrylate is more preferred. 2-(vinyloxyethoxy)ethyl acrylate is particularly easy to polymerize, but by applying the production method of the present invention, polymerization in the liquid phase can be sufficiently prevented. ,

[0090] The above reaction step is preferably carried out in an atmosphere in which the molecular oxygen concentration in the gas phase of the reaction system is 0.001 to 21% by volume. By setting the molecular oxygen concentration in the gas phase to such a range, the polymerization reaction in the above reaction step can be more efficiently prevented, and the (meth)acrylate having a vinyl ether group can be produced in high yield. The molecular oxygen concentration in the gas phase is more preferably 0.005 to 15% by volume, and further preferably 0.01 to 10% by volume.

[0091] As methods for adjusting the molecular oxygen concentration in the gas phase of the above-mentioned reaction system to the above-mentioned preferred range, the following methods can be listed: (a) a method of supplying a gas containing molecular oxygen such as molecular oxygen or air to the reaction container (where the steam is present) during the reaction to adjust the molecular oxygen concentration in the gas phase; (b) a method of supplying a gas containing molecular oxygen such as molecular oxygen or air and an inert gas such as nitrogen or argon to the reaction container (where the steam is present) during the reaction to adjust the molecular oxygen concentration in the gas phase; (c) a method of pre-mixing a gas containing molecular oxygen such as molecular oxygen or air and an inert gas such as nitrogen or argon and supplying the mixture to the reaction container (where the steam is present) during the reaction to adjust the molecular oxygen concentration in the gas phase, etc.

[0092] In addition, as a method for supplying molecular oxygen and / or a mixed gas containing molecular oxygen to the reaction system, it is sufficient to supply it continuously or intermittently to one or both of the liquid phase and the gas phase in the reaction system.

[0093] In addition, since the reaction in the above-mentioned reaction step is an ester exchange reaction, alcohol is by-produced as the reaction proceeds, and the by-produced alcohol is preferably removed to the outside of the reaction system.

[0094] As the method for removing the by-product alcohol, for example, a method of reacting under reduced pressure, a method of reacting using an azeotropic solvent, a method of reacting in the presence of an adsorbent, etc. can be cited. Among these, a method of reacting under reduced pressure, a method of reacting using an azeotropic solvent, etc. are preferred.

[0095] As the above-mentioned azeotropic solvent, there is no particular limitation as long as it does not hinder the transesterification reaction, and examples thereof include ethers such as diethyl ether, diisopropyl ether, and dibutyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as pentane, hexane, heptane, and cyclohexane; halogenated hydrocarbons such as chloroform, dichloromethane, 1,2-dichloroethane, and chlorobenzene. These azeotropic solvents can be used alone or in combination of two or more. In addition, the raw material (meth)acrylate used in excess can also be used as an azeotropic solvent.

[0096] The amount of the azeotropic solvent used is not particularly limited, for example, preferably 0 to 300% by mass of the mass of the hydroxyl-containing vinyl ether compound as a reaction raw material. From the viewpoint of yield and economic efficiency, the amount of the azeotropic solvent is preferably in this range. The amount is more preferably 1 to 200% by mass, further preferably 2 to 150% by mass, and particularly preferably 3 to 100% by mass.

[0097] The reaction temperature in the above-mentioned reaction step is not particularly limited, and is preferably above the boiling point or azeotropic temperature of the by-product alcohol. Specifically, it is preferably set to above 40°C, more preferably above 50°C, and further preferably above 60°C. Thus, the by-product alcohol can be fully removed. In addition, the reaction temperature is preferably set to below 180°C, more preferably below 140°C, and further preferably below 100°C. Thus, from the viewpoint that the polymerization reaction of the easily polymerizable compound becomes difficult to proceed, the anti-polymerization effect becomes more significant. The reaction pressure is not particularly limited, and normal pressure, pressurization, and reduced pressure are all possible. As described above, from the viewpoint of removing the by-product alcohol, reduced pressure is preferably used. In addition, the reaction time can be appropriately set in the manner in which the reaction in the above-mentioned reaction step is completed, and can be set to, for example, 3 to 20 hours.

[0098] The production method of the present invention may include other steps described later, as long as it includes the above-mentioned reaction step.

[0099] [Purification after the reaction step]

[0100] In the production method of the present invention, after the above-mentioned reaction step, the obtained (meth)acrylate having a vinyl ether group can be purified and isolated from the reaction solution.

[0101] The method for performing the purification step is not particularly limited, and examples thereof include methods based on raw material recovery operation, catalyst recovery operation, neutralization operation, filtration operation, decantation operation, extraction operation, water washing operation, evaporation operation, distillation operation, column chromatography operation, and the like.

[0102] The above-mentioned operations may be carried out alone or in combination of two or more thereof. Among these, purification by distillation operation is particularly preferred.

[0103] Furthermore, impurities removed by purification can be reused as raw materials or preparations as necessary.

[0104] <Step of separating raw material (meth)acrylate>

[0105] For example, the production method of the present invention preferably includes a step of separating unreacted raw material (meth)acrylic acid ester after the above-mentioned reaction step.

[0106] In the step of separating the raw material (meth)acrylic acid ester, it is preferred to separate the raw material (meth)acrylic acid ester by evaporating the raw material (meth)acrylic acid ester by distillation.

[0107] The separated raw material (meth)acrylate can be recovered and reused as a raw material (meth)acrylate in the reaction step or the like.

[0108] The temperature in the separation step of the raw material (meth)acrylate can be appropriately set according to the boiling point of the raw material (meth)acrylate, etc. The pressure is not particularly limited, and may be normal pressure, pressurized, or reduced pressure, preferably reduced pressure. In addition, the time can be appropriately set so that the raw material (meth)acrylate can be fully removed.

[0109] <Catalyst Separation Step>

[0110] For example, the production method of the present invention preferably includes a step of separating the catalyst after the above-mentioned reaction step.

[0111] In the above-mentioned catalyst separation step, the catalyst is preferably separated by evaporating the target product, the (meth)acrylate having a vinyl ether group, by distillation. Thus, impurities having a higher boiling point than the target product, the (meth)acrylate having a vinyl ether group, can be removed together with the catalyst.

[0112] The temperature in the catalyst separation step is usually higher than the temperature in the raw material (meth)acrylate separation step, and can be appropriately set according to the boiling point of the (meth)acrylate having a vinyl ether group as the target product. The pressure is not particularly limited, and may be normal pressure, pressurized, or reduced pressure, preferably reduced pressure. In addition, the time can be appropriately set.

[0113] <Step of Purifying (Meth) Acrylic Acid Ester Having Vinyl Ether Group>

[0114] The production method of the present invention preferably further comprises a step of purifying the (meth)acrylate having a vinyl ether group after, for example, the reaction step, the step of separating the raw material (meth)acrylate, and the step of separating the catalyst.

[0115] In the purification step of the (meth)acrylate having a vinyl ether group, it is preferred to separate the (meth)acrylate having a vinyl ether group by evaporating the (meth)acrylate having a vinyl ether group by distillation. In this way, impurities having a higher boiling point than the (meth)acrylate having a vinyl ether group can be removed. In addition, for example, it is more preferred to separate the (meth)acrylate having a vinyl ether group by evaporating the (meth)acrylate having a vinyl ether group by distillation after removing impurities having a lower boiling point than the (meth)acrylate having a vinyl ether group by distillation.

[0116] The purification step of the (meth)acrylate having a vinyl ether group is preferably performed using a distillation column. As a distillation column, for example, an Oldershaw type distillation column can be cited as a suitable distillation column.

[0117] The temperature in the purification process of the (meth)acrylate having a vinyl ether group can be appropriately set according to the boiling point of the (meth)acrylate having a vinyl ether group, the boiling point of impurities, etc. The pressure is not particularly limited, and normal pressure, pressurization, and reduced pressure are all possible, preferably reduced pressure. In addition, the time can be appropriately set.

[0118] Figure 1 This is a diagram showing an example of a production apparatus for carrying out the production method of the present invention.

[0119] Figure 1 The apparatus includes a reaction tank 11 for transesterification reaction, a first distillation column 21 for evaporating the raw material (meth)acrylate and separating it from the (meth)acrylate having a vinyl ether group, and a second distillation column 31 for evaporating the (meth)acrylate having a vinyl ether group and separating the catalyst and high-boiling impurities from the (meth)acrylate having a vinyl ether group.

[0120] The raw material solution 1 supplied to the apparatus is first introduced into the reaction tank 11. When the transesterification reaction is carried out in the reaction tank 11, by making the mass ratio of the compound represented by formula (1) and the phosphite in the raw material solution 1 0.8 mass % or more, it is possible to obtain a (meth)acrylic acid ester having a vinyl ether group while fully preventing the polymerization of the (meth)acryloyl group. It should be noted that, although not shown in the figure, when the alcohol produced as a by-product in the transesterification reaction is generally a low-boiling component, it can also be evaporated and removed from the reaction tank 11. The solution containing the obtained (meth)acrylic acid ester having a vinyl ether group is sent to the first distillation tower 21 through the pipeline 71. In the first distillation tower 21, the unreacted raw material (meth)acrylic acid ester is evaporated and separated. The separated raw material (meth)acrylic acid ester is returned to the reaction tank 11 through the pipeline 81. The solution containing the (meth)acrylic acid ester having a vinyl ether group as the bottom liquid in the first distillation tower 21 is sent to the second distillation tower 31 through the pipeline 72. In the second distillation tower 31, the (meth)acrylic acid ester having a vinyl ether group is evaporated, and a crude product 3 is obtained from the top of the second distillation tower 31. The bottom liquid in the second distillation tower 31 contains a large amount of impurities having a higher boiling point than the (meth)acrylic acid ester having a vinyl ether group, such as a catalyst, and is therefore removed as a waste oil 2.

[0121] The (meth)acrylate having a vinyl ether group obtained by the production method of the present invention can be suitably used as a raw material for various industrial products.

[0122] Example

[0123] The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples. It should be noted that, unless otherwise specified, "parts" means "parts by weight" and "%" means "mass %".

[0124] [Production Example 1]

[0125] A 2 L glass round-bottom flask (reactor) equipped with an Oldershaw type distillation column, a stirring device, a thermometer, a gas introduction pipe, and a liquid sequential feeding line was prepared. Into the round-bottom flask were added 620 g of methyl acrylate (hereinafter abbreviated as "AM"), 453 g of diethylene glycol monovinyl ether (hereinafter abbreviated as "DEGV"), 1.1 g of phenothiazine (hereinafter abbreviated as "PTZ") as a primary antioxidant, 0.32 g of N-nitrosophenylhydroxylamine ammonium salt (hereinafter abbreviated as "NPHN"), and 2.1 g of dibutyltin oxide (hereinafter abbreviated as "DBTO") as a catalyst.

[0126] Next, while liquid-phase bubbling of an oxygen / nitrogen mixed gas adjusted to 7 vol% was performed from the gas inlet pipe at 15 ml / min, the reactor was immersed in an oil bath at 120° C., and the temperature was started under total reflux.

[0127] As the reaction proceeds, methanol as a by-product gradually concentrates at the top of the Oldershaw type distillation column. After the temperature at the top of the column reaches the azeotropic point of AM and methanol, 63°C, distillation begins at a reflux ratio of 8 and a take-off rate of 50 g / h. At the same time, AM is supplied to the reactor through the liquid sequential feed line at a rate equal to the distillation rate. The start of distillation is regarded as the start of the reaction (reaction time is 0 hours), and the reaction is carried out for 8 hours.

[0128] Next, the reaction liquid after the reaction was completed was subjected to single distillation (operating pressure of 20 hPa; ended when the liquid temperature reached 100°C) to remove unreacted AM, and further, the reaction product was removed under the conditions of operating pressure of 20 hPa and distillation rate of 75% (distillation was performed at a constant distillation rate for 14 hours). In this way, a catalyst-containing residue was obtained as a test liquid for a liquid polymerization stability test.

[0129] [Example 1]

[0130] Into a transparent glass test tube (inner diameter 18 mm, length 180 mm; manufactured by MARUEMU Co., Ltd.), 5 g of the test solution obtained in Preparation Example 1, 0.05 g each of N,N'-bis{2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl}oxamide (product name: ANTAGE HP-200 / Kawaguchi Chemical Co., Ltd.) (hereinafter abbreviated as "HP-200") and tris(2,4-di-tert-butylphenyl)phosphite (product name: JP-650 / Johoku Chemical Industry Co., Ltd.) (hereinafter abbreviated as "JP-650") as an anti-polymerization agent were added (each at 1% by mass relative to the test solution).

[0131] Next, the test tube was sealed with a silicone stopper and immersed in an oil bath at 100° C. to measure the polymerization time. The time when a part of the test liquid was confirmed to be solidified was considered to be polymerization, and the time until then was considered to be the polymerization time. The results are shown in Table 1.

[0132] [Comparative Examples 1 to 3]

[0133] The liquid polymerization stability test described in Example 1 was performed by changing the amount of the anti-polymerization agent added as shown in Table 1. The results are shown in Table 1.

[0134] [Table 1]

[0135]

[0136] HP-200: N,N′-bis{2-[3-(3,-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl}oxalamide

[0137] JP-650: Tris(2,4-di-tert-butylphenyl)phosphite

[0138] (Summarize)

[0139] Compared with Comparative Example 1 in which no anti-polymerization agent was added, in Comparative Examples 2 and 3, each of which used only one anti-polymerization agent, a tendency of prolonged polymerization time and improved liquid stability was confirmed. Furthermore, in Example 1 in which two anti-polymerization agents were used in combination, the polymerization time was further prolonged, indicating that there was a synergistic effect by using the two anti-polymerization agents in combination.

[0140] [Comparative Example 4]

[0141] Into a jacketed reactive distillation reactor were placed 1364 kg of AM, 997 kg of DEGV, 2.4 kg of PTZ as a primary antioxidant, 0.70 kg of NPHN, and 4.6 kg of DBTO as a catalyst.

[0142] Next, a mixed gas of oxygen / nitrogen with an oxygen concentration adjusted to 7% by volume was added at 2 Nm 3 / h was bubbled into the liquid from the gas introduction pipe, and steam was supplied to the jacket under total reflux to start heating. The reaction temperature was set to 120°C.

[0143] As the reaction proceeds, methanol as a by-product gradually concentrates at the top of the distillation tower. After the temperature at the top reaches the azeotropic point of AM and methanol, 63°C, distillation begins at a reflux ratio of 8 and a flow rate of 110 kg / h. At the same time, AM is supplied to the reactor through the liquid sequential injection line at the same flow rate. The start of distillation is regarded as the start of the reaction (reaction time is 0 hours), and the reaction is carried out in a batch for 8 hours. In addition, in order to prevent polymerization inside the reactor, a 1% by mass PTZ / AM solution is supplied from the top of the distillation tower at a flow rate of 11 kg / h.

[0144] Next, unreacted AM in the reaction liquid after the completion of the above reaction was distilled off (operating pressure of 20 hPa; completed when the liquid temperature reached 100°C), and then the reaction product was further distilled off over 14 hours under the conditions of an operating pressure of 20 hPa and a distillation rate of 75% (constant distillation rate) (catalyst separation step).

[0145] When the above reaction and distillation were repeated, during the 8th (8th batch) reaction, in the catalyst separation step, an abnormal current value occurred in the pump for transferring the bottom liquid after catalyst separation, and the pump stopped operating. When the surrounding parts of the pump were checked, polymers of the reaction product were generated in the suction filter and piping of the pump, causing clogging.

[0146] [Comparative Example 5]

[0147] In Comparative Example 4, the same operation as in Comparative Example 4 was carried out except that JP-650 was additionally added as an anti-polymerization agent so as to be 0.2 mass % based on the reaction solution.

[0148] As a result, during the 10th reaction (10th batch), in the catalyst separation step, the pump for transferring the bottom liquid after catalyst separation had an abnormal current value and stopped operating. When checking the surrounding parts of the pump, polymers of the reaction product were generated in the suction filter and piping of the pump, causing clogging.

[0149] [Comparative Example 6]

[0150] In Comparative Example 4, the same operation as in Comparative Example 4 was carried out except that HP-200 was additionally added as an anti-polymerization agent so as to be 0.2 mass % based on the reaction solution.

[0151] As a result, during the 58th reaction (58th batch), in the catalyst separation step, the pump for transferring the bottom liquid after catalyst separation had an abnormal current value and stopped operating. When checking the surrounding parts of the pump, it was found that polymers of the reaction product were generated in the suction filter and piping of the pump, causing clogging.

[0152] [Example 2]

[0153] In Comparative Example 4, the same operation as in Comparative Example 4 was carried out except that JP-650 and HP-200 were additionally added as anti-polymerization agents so as to be 0.2 mass % each with respect to the reaction solution.

[0154] As a result, in the 80th reaction (80th batch), no abnormality occurred in the pump for transferring the bottom liquid after the catalyst separation, and in the internal inspection after the operation, no clogging due to the polymer was observed in the pipes.

[0155] [Table 2]

[0156]

[0157] HP-200: N,N′-bis{2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl}oxalamide

[0158] JP-650: Tris(2,4-di-tert-butylphenyl)phosphite

[0159] (Summarize)

[0160] It was confirmed that the combined use of two anti-polymerization agents (HP-200 and JP-650) exhibited a superior anti-polymerization effect compared to the use of each agent alone.

Claims

1. A method for producing a (meth)acrylate having a vinyl ether group, characterized in that: The method comprises the following steps: using a raw material solution containing a raw material (meth)acrylate, a hydroxyl-containing vinyl ether compound and a catalyst, obtaining a (meth)acrylate having a vinyl ether group through an ester exchange reaction; The raw material solution further comprises a compound represented by the following formula (1) and a phosphite, wherein the mass ratio of the compound represented by the following formula (1) is 0.2 mass % or more, and the mass ratio of the phosphite is 0.2 mass % or more in the raw material solution. In the above formula, R 1 ~R 4 are the same or different and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms; m, n, p, and q are the same or different and are integers of 1 to 4.

2. The method for producing a (meth)acrylate having a vinyl ether group according to claim 1, wherein: The hydroxyl-containing vinyl ether compound is diethylene glycol monovinyl ether, The (meth)acrylate having a vinyl ether group is 2-(2-vinyloxyethoxy)ethyl (meth)acrylate.

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