Active energy ray-curable resin composition and concrete protection material

Abstract

To provide an active energy ray-curable resin composition having excellent workability and curability and capable of providing a coating film having an excellent self-repairing property.SOLUTION: Used is an active energy ray-curable resin composition, comprising an epoxy (meth)acrylate (A), a photoinitiator (B), and a transesterification catalyst (C), where the epoxy (meth)acrylate (A) has a hydroxyl group concentration of 2 mmol / g or more and a content of the transesterification catalyst (C) is 0.5 mol% or more relative to the hydroxyl groups possessed by the epoxy (meth)acrylate (A).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an active energy ray-curable resin composition and a concrete protection material. [Background technology]

[0002] Protective materials for outdoor concrete structures are required to have workability and fast curing properties that allow construction to be completed in a short time. Examples of such materials include (meth)acrylate resins. An active energy ray-curable concrete protection material containing a specific mass ratio of a resin, a (meth)acrylic monomer, a photopolymerization initiator, and a wax has been proposed (see, for example, Patent Document 1).

[0003] Meanwhile, due to the growing need for long-term durability, there has been a demand for concrete protection materials that have the ability to self-repair scratches that occur in the coating. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-153109 A Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the present invention is to provide an active energy ray-curable resin composition which is excellent in workability and curability and which can give a coating film having excellent self-repairing properties. [Means for solving the problem]

[0006] As a result of intensive research to solve the above problems, the inventors of the present invention have found that an active energy ray-curable resin composition containing a specific epoxy (meth) acrylate (A), a photopolymerization initiator (B), and a transesterification catalyst (C) in a specific ratio is excellent in workability and curability, and a coating film excellent in self-healing properties can be obtained, thus completing the present invention.

[0007] That is, the present invention provides an active energy ray-curable resin composition containing an epoxy (meth) acrylate (A), a photopolymerization initiator (B), and a transesterification catalyst (C), wherein the hydroxyl group concentration of the epoxy (meth) acrylate (A) is 2 mmol / g or more, and the content of the transesterification catalyst (C) is 0.5 mol% or more based on the hydroxyl groups of the epoxy (meth) acrylate (A).

Effects of the Invention

[0008] Since the active energy ray-curable resin composition of the present invention is excellent in workability and curability, and a coating film excellent in self-healing properties can be obtained, it can be suitably used in the construction of various civil engineering and building materials such as concrete protection materials.

Modes for Carrying Out the Invention

[0009] The active energy ray-curable resin composition of the present invention is an active energy ray-curable resin composition containing an epoxy (meth) acrylate (A), a photopolymerization initiator (B), and a transesterification catalyst (C), wherein the hydroxyl group concentration of the epoxy (meth) acrylate (A) is 2 mmol / g or more, and the content of the transesterification catalyst (C) is 0.5 mol% or more based on the hydroxyl groups of the epoxy (meth) acrylate (A).

[0010] In the present invention, "(meth)acrylate" refers to one or both of methacrylate and acrylate, "(meth)acrylic monomer" refers to one or both of acrylic monomer and methacrylic monomer, and "(meth)acryloyl" refers to one or both of acryloyl and methacryloyl.

[0011] As the epoxy (meth)acrylate, for example, those obtained by reacting an epoxy resin with an unsaturated monobasic acid by a conventionally known method can be used.

[0012] Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol fluorene type epoxy resin, bisphenol type epoxy resins such as bis-cresol fluorene type, phenol novolac type epoxy resin, cresol novolac type epoxy resin and other novolac type epoxy resins, oxazolidone modified epoxy resin, glycidyl ethers of phenols such as brominated epoxy resins of these resins, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, diglycidyl ether of alkylene oxide adduct of bisphenol A, glycidyl ethers of polyhydric alcohols such as diglycidyl ether of hydrogenated bisphenol A, alicyclic epoxy resins such as 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, 1-epoxyethyl-3,4-epoxycyclohexane, glycidyl esters such as diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl-p-oxybenzoic acid, glycidyl ester of dimer acid, glycidyl amines such as tetraglycidyl diaminodiphenylmethane, tetraglycidyl-m-xylenediamine, triglycidyl-p-aminophenol, N,N-diglycidylaniline, and heterocyclic epoxy resins such as 1,3-diglycidyl-5,5-dimethylhydantoin, triglycidyl isocyanurate. Among these, bifunctional or trifunctional epoxy resins are preferred because the self-healing property is further improved. These epoxy resins can be used alone or in combination of two or more.

[0013] Examples of the unsaturated monobasic acid include (meth)acrylic acid, cinnamic acid, crotonic acid, monomethyl maleate, monopropyl maleate, monobutene maleate, sorbic acid, mono(2-ethylhexyl) maleate and the like. These unsaturated monobasic acids may be used alone or in combination of two or more.

[0014] The epoxy (meth)acrylate (A) has a (meth)acryloyl group that allows radical polymerization to proceed upon light irradiation, heating, or the like. The (meth)acryloyl group equivalent of the (meth)acrylate (A) is preferably 200 to 8,000 g / eq, more preferably 250 to 5,000 g / eq, because the balance of low viscosity, curability, and self-healing properties can be further improved. Here, the (meth)acryloyl group equivalent is a value obtained by calculation from the raw material composition.

[0015] The weight average molecular weight of the epoxy (meth)acrylate (A) is preferably 400 to 15,000 because the balance of low viscosity, curability, and self-healing properties can be further improved.

[0016] The average molecular weight in the present invention indicates a value measured by the gel permeation chromatography (GPC) method.

[0017] The average functionality of the epoxy (meth)acrylate (A) is preferably 1.5 to 3.5, more preferably 1.8 to 2.5, because the balance of low viscosity, curability, and self-healing properties can be further improved.

[0018] Examples of the photopolymerization initiator (B) include acetophenone compounds such as 4-phenoxydichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl) ketone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,2-dimethoxy-2-phenylacetophenone; benzoin compounds such as benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether; benzophenone compounds such as benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3'-dimethyl-4-methoxybenzophenone; thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone; anthraquinone compounds such as 4,4'-dimethylaminothioxanthone (alias = miners ketone), 4,4'-diethylaminobenzophenone, α-acyloxime ester, benzyl, methyl benzoylformate ("Byakure 55"), 2-ethylanthraquinone; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide; 3,3',4,4'-tetra(tert-butyloxycarbonyl)benzophenone, acrylated benzophenone, etc. These photopolymerization initiators (B) may be used alone or in combination of two or more.

[0019] As the photopolymerization initiator (B), 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide are preferably used because the curability is further improved.

[0020] Since a coating film excellent in curability can be obtained, the amount of the photopolymerization initiator (B) used is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 5 parts by mass, based on 100 parts by mass of the epoxy (meth)acrylate (A).

[0021] Examples of the transesterification catalyst (C) include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; sodium methoxide, sodium Alkoxides of various metals such as phenoxide, potassium ethoxide, tetraethyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate; complexes of various metals such as zinc acetylacetonate, zirconium acetylacetonate; organotin compounds such as dibutyltin dimethoxide, dibutyltin oxide, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate; strongly basic amine compounds such as N,N'-dimethylaminopyridine (DMAP), 1,8-diazabicyclo[5.4.0]undecene-7 (DBU), 1,5-diazabicyclo[4.3.0]nonene-5 (DBN), 1,4-diazabicyclo[2.2.2]octane (DABCO); various quaternary ammonium salts such as tetramethylammonium salts, tetrabutylammonium salts, trimethyl(2-hydroxypropyl)ammonium salts, cyclohexyltrimethylammonium salts, tetrakis(hydroxymethyl)ammonium salts, dilauryl dimethylammonium salts, tributylmethylammonium salts, etc., having various carboxylates such as acetate, propionate or anions such as chloride, bromide, hydroxide as counter anions, so-called quaternary ammonium salts; tetramethylphosphonium salts, tetraethylphosphonium salts, tetrapropylphosphonium salts; tetrabutylphosphonium salts, trimethyl(2-hydroxypropyl)phosphonium salts, having carboxylates such as acetate, propionate or phosphonium salts such as chloride, bromide, hydroxide as counter anions; acidic compounds such as methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, octanesulfonic acid, trifluoroacetic acid, phosphoric acid, sulfuric acid, hydrochloric acid; salts of the above-mentioned acidic compounds with nitrogen-containing basic compounds such as ammonia, triethylamine, diethanolamine, triethanolamine, etc. Among these, organometallic compounds such as alkoxides of various metals, complexes of various metals, and organotin compounds are preferred because the self-healing property is further improved. These esterification catalysts (C) may be used alone or in combination of two or more.

[0022] The content of the transesterification catalyst (C) is 0.5 mol% or more based on the hydroxyl group of the epoxy (meth)acrylate (A). However, since the self-healing property is further improved, 2 to 15 mol% is preferable, and 5 to 10 mol% is more preferable.

[0023] The active energy ray-curable resin composition of the present invention contains the epoxy (meth)acrylate (A), the photopolymerization initiator (B), and the transesterification catalyst (C), and may contain other additives and the like as necessary.

[0024] Examples of the other additives include (meth)acrylic monomers, polymerization inhibitors, antioxidants, light stabilizers, solvents, rust inhibitors, thixotropic agents, sensitizers, leveling agents, tackifiers, antistatic agents, flame retardant curing agents, curing accelerators, pigments, fillers, reinforcing materials, aggregates, and the like.

[0025] Examples of the (meth)acrylic monomer include (meth)acrylic monomers having an alicyclic structure such as isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentenyl oxyethyl (meth)acrylate; aliphatic (meth)acrylic monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, sec-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylbutyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, heptyl (meth)acrylate, n-octyl (meth)acrylate, nonyl (meth)acrylate, dodecyl (meth)acrylate, 3-methylbutyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, neopentyl (meth)acrylate, hexadecyl (meth)acrylate, and isoamyl (meth)acrylate; (meth)acrylic monomers having an ether group such as 3-methoxybutyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, and methoxypolyethylene glycol acrylate with an added mole number of oxyethylene in the range of 1 to 15, ethoxy-diethylene glycol (meth)acrylate, and ethyl carbitol (meth)acrylate; (meth)acrylic monomers having a hydroxyl group such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; aromatic (meth)acrylic monomers such as benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypolyethylene glycol acrylate, phenyl (meth)acrylate, and 2-hydroxy-3-phenoxypropyl (meth)acrylate;(Meth)acrylic monomers having a nitrogen atom such as (meth)acrylamide, dimethyl(meth)acrylamide, acryloylmorpholine, dimethylaminopropyl(meth)acrylamide, isopropyl(meth)acrylamide, diethyl(meth)acrylamide, diacetone(meth)acrylamide, hydroxyethylacrylamide, etc. can be used. These (meth)acrylic monomers may be used alone or in combination of two or more kinds.;

[0026] The active energy rays for curing the active energy ray-curable resin composition of the present invention are ionizing radiations such as ultraviolet rays, electron beams, α-rays, β-rays, and γ-rays. Specific energy sources or curing devices include, for example, ultraviolet rays using a germicidal lamp, a fluorescent lamp for ultraviolet rays, a carbon arc, a xenon lamp, a high-pressure mercury lamp for copying, a medium-pressure or high-pressure mercury lamp, an ultra-high-pressure mercury lamp, an electrodeless lamp, a metal halide lamp, a fluorescent chemical lamp, natural light, etc. as a light source, or electron beams by a scanning type or curtain type electron beam accelerator, etc.

[0027] The active energy ray-curable resin composition of the present invention can be used, for example, as a protective material for concrete such as cement concrete, asphalt concrete, mortar concrete, resin concrete, permeable concrete, ALC (Autoclaved Lightweight Aerated Concrete) board, etc.

[0028] Since the concrete protective material of the present invention is excellent in workability and curability and a coating film excellent in self-healing property can be obtained, it can be suitably used in the construction of various civil engineering and building materials such as concrete repair materials and waterproof materials.

Examples

[0029] The present invention will be described in more detail with specific examples below. The average molecular weight was measured under the following GPC measurement conditions.

[0030] [GPC measurement conditions] Measuring device: High-speed GPC device ("HLC-8220GPC" manufactured by Tosoh Corporation) Column: The following columns manufactured by Tosoh Corporation were connected in series and used. "TSKgel G5000" (7.8 mm I.D. × 30 cm) × 1 piece "TSKgel G4000" (7.8 mm I.D. × 30 cm) × 1 piece "TSKgel G3000" (7.8 mm I.D. × 30 cm) × 1 piece "TSKgel G2000" (7.8 mm I.D. × 30 cm) × 1 piece Detector: RI (differential refractometer) Column temperature: 40 °C Eluent: Tetrahydrofuran (THF) Flow rate: 1.0 mL / min Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 4 mg / mL) Standard sample: A calibration curve was created using the following monodisperse polystyrene.

[0031] (Monodisperse polystyrene) "TSKgel Standard Polystyrene A-500" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene A-1000" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene A-2500" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene A-5000" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-1" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-2" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-4" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-10" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-20" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-40" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-80" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-128" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-288" manufactured by Tosoh Corporation "TSKgel Standard Polystyrene F-550" manufactured by Tosoh Corporation

[0032] (Synthesis Example 1: Synthesis of Epoxy (Meth)acrylate (A-1)) Into a four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet, and a reflux condenser, 1850 parts by mass of a bisphenol type epoxy compound ("Epiclon 850" manufactured by DIC Corporation), 860 parts by mass of acrylic acid, 1.36 parts by mass of hydroquinone, and 10.8 parts by mass of triethylamine were charged, heated to 120 °C, and reacted for 10 hours at the same temperature to obtain an epoxy (meth)acrylate resin (A-1) having an acid value of 3.5, a number average molecular weight of 513, and a hydroxyl group concentration of 3.9 mmol / g.

[0033] (Synthesis Example 2: Synthesis of Epoxy (Meth)acrylate (A-2)) Into a four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet, and a reflux condenser, 1850 parts by mass of propylene glycol diglycidyl ether, 860 parts by mass of acrylic acid, 1.36 parts by mass of hydroquinone, and 10.8 parts by mass of triethylamine were charged, heated to 120 °C, and reacted for 10 hours at the same temperature to obtain an epoxy (meth)acrylate (A-2) having an acid value of 0.5, a number average molecular weight of 332, and a hydroxyl group concentration of 6.0 mmol / g.

[0034] (Example 1: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (1)) Into a light-shielding container equipped with a stirrer, a reflux condenser tube, and a thermometer, 100 parts by mass of the epoxy (meth)acrylate (A-1) obtained in Synthesis Example 1, 1.5 parts by mass of 2,4,6-trimethylbenzoyldiphenylphosphine oxide (hereinafter abbreviated as "photoinitiator (B-1)"), and 25 parts by mass of dibutyltin laurate (hereinafter abbreviated as "transesterification catalyst (C-1)") were blended, stirred at 80 °C until uniform, and an active energy ray-curable resin composition (1) was obtained.

[0035] [Evaluation of Workability (Viscosity)] The active energy ray-curable resin composition (1) obtained above was measured with a B-type viscometer ("TV-22" manufactured by Toki Sangyo Co., Ltd.) under the condition of 25°C and evaluated according to the following criteria. ○: Less than 5,000 mPa·s ×: 5,000 mPa·s or more

[0036] [Preparation of Cured Coating Film] The resin was poured into a mold frame with a width of 0.5 mm and a thickness of 50 μm made of polyethylene terephthalate film (release PET50). Then, ultraviolet rays of 1000 mJ / cm2 were irradiated with an ultraviolet irradiation device (fluorescent chemical lamp) to prepare a cured coating film.

[0037] [Evaluation of Curability] The presence or absence of tack on the surface of the coating film obtained above was confirmed by finger touch. ○: No tack ×: Tack present

[0038] [Evaluation of Self-Healing Property] A scratch with a length of 3.0 cm and a depth of 0.2 mm was made on the coating film obtained above using a cutter knife. This coating film was left standing in an environment of 160°C, and the time until the scratch disappeared was measured, and the self-healing property was evaluated according to the following criteria. In addition, the scratch marks were confirmed every 10 minutes and the process ended after 150 minutes. 〇: Those in which the scratch marks disappeared within 150 minutes ×: Those in which the scratch marks remained after 150 minutes

[0039] (Example 2: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (2)) An active energy ray-curable resin composition (2) was prepared in the same manner as in Example 1, except that the epoxy (meth)acrylate (A-1) used in Example 1 was changed to epoxy (meth)acrylate (A-2), and then each physical property was evaluated.

[0040] (Example 3: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (4)) The transesterification catalyst (C-1) used in Example 1 was changed to zinc acetylacetonate (hereinafter abbreviated as "transesterification catalyst (C-2)"), and an active energy ray-curable resin composition (3) was prepared in the same manner as in Example 1, and then each physical property was evaluated.

[0041] (Example 4: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (4)) The transesterification catalyst (C-1) used in Example 1 was changed to tetraethyl titanate (hereinafter abbreviated as "transesterification catalyst (C-3)"), and an active energy ray-curable resin composition (4) was prepared in the same manner as in Example 1, and then each physical property was evaluated.

[0042] (Example 5: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (5)) The transesterification catalyst (C-1) 10 parts by mass used in Example 1 was changed to 1 part by mass, and an active energy ray-curable resin composition (5) was prepared in the same manner as in Example 1, and then each physical property was evaluated.

[0043] (Example 6: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (6)) The transesterification catalyst (C-1) 10 parts by mass used in Example 1 was changed to 20 parts by mass, and an active energy ray-curable resin composition (6) was prepared in the same manner as in Example 1, and then each physical property was evaluated.

[0044] (Example 7: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (7)) The epoxy (meth)acrylate (A-1) 100 parts by mass used in Example 1 was changed to epoxy (meth)acrylate (A-1) 75 parts by mass and acryloylmorpholine (hereinafter abbreviated as "ACMO") 25 parts by mass, and an active energy ray-curable resin composition (7) was prepared in the same manner as in Example 1, and then each physical property was evaluated.

[0045] (Comparative Example 1: Preparation and Evaluation of Active Energy Ray-Curable Resin Composition (R1)) An active energy ray-curable resin composition (R1) was prepared in the same manner as in Example 1, except that 10 parts by mass of the transesterification catalyst (C-1) used in Example 1 was changed to 0.005 parts by mass, and then each physical property was evaluated.

[0046] (Comparative Example 2: Preparation and Evaluation of Active Energy Ray-Curable Concrete Protective Material (R2)) An active energy ray-curable resin composition (R2) was prepared in the same manner as in Example 1, except that the epoxy (meth)acrylate (A-1) used in Example 1 was changed to EO-modified bisphenol A dimethacrylate ("FA-321M" manufactured by Showa Denko Materials Co., Ltd.), and then each physical property was evaluated.

[0047] The compositions and evaluation results of the active energy ray-curable resin compositions obtained above are shown in Tables 1 and 2.

[0048] [Table 1]

[0049] [Table 2]

[0050] It was confirmed that the active energy ray-curable resin compositions of the present invention in Examples 1 to 7 have low viscosity and excellent workability, and a coating film excellent in curability and self-healing property can be obtained.

[0051] Comparative Example 1 is an example in which the content of the transesterification catalyst (C) is less than the lower limit, but it was confirmed that the self-healing property of the coating film is insufficient.

[0052] Comparative Example 2 is an example in which EO-modified bisphenol A dimethacrylate is used instead of epoxy (meth)acrylate (A), but it was confirmed that the self-healing property of the coating film is insufficient.

Claims

1. A concrete protection material comprising an active energy ray-curable resin composition containing epoxy (meth)acrylate (A), a photopolymerization initiator (B), and a transesterification catalyst (C), wherein the hydroxyl group concentration of the epoxy (meth)acrylate (A) is 2 mmol / g or more, and the content of the transesterification catalyst (C) is 0.5 mol% or more based on the hydroxyl groups possessed by the epoxy (meth)acrylate (A). A concrete protection material characterized by the above.

2. The concrete protection material according to Claim 1, wherein the transesterification catalyst (C) is an organometallic compound.

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