JP2019210190A - Active energy ray-curable concrete protective material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concrete protective material having a low viscosity, excellent workability, excellent quick-curing property, and capable of obtaining a coating film excellent in flexibility. A urethane (meth) acrylate (A), a (meth) acrylic monomer (B), and a photopolymerization initiator (C) are contained, and the urethane (meth) acrylate (A) has a weight average molecular weight of It is in the range of 7,000 to 20,000, the average number of functional groups is in the range of 0.5 to 1.5, and the content of the (meth) acrylic monomer (B) is the urethane (meth) acrylate ( A) An active energy ray-curable concrete protective material characterized in that it is in the range of 30 to 500 parts by mass with respect to 100 parts by mass. [Selection diagram] None

Description

  The present invention relates to an active energy ray-curable concrete protective material.

  Waterproofing materials for outdoor concrete structures are required to have flexibility to follow the base material even under low temperature conditions, in addition to quick curing that can be completed in a short time. As such a material, a concrete protective material containing urethane (meth) acrylate, (meth) acrylic monomer, and a photopolymerization initiator has been proposed (for example, see Patent Document 1).

  However, this material has a problem of high viscosity and insufficient workability such as sprayability. Therefore, there has been a demand for a material that can provide a coating film having low viscosity, excellent quick curability, and excellent flexibility.

JP 2018-3357 A

  The problem to be solved by the present invention is to provide a concrete protective material that has a low viscosity and excellent workability, is excellent in fast curability, and provides a coating film with excellent flexibility.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have an active energy containing a specific urethane (meth) acrylate, (meth) acrylic monomer, and photopolymerization initiator at a specific mass ratio. The present inventors have found that a wire curable concrete protective material has a low viscosity, excellent workability, excellent curability, and high elongation coating with excellent crack followability, thereby completing the present invention.

  That is, this invention contains urethane (meth) acrylate (A), (meth) acrylic monomer (B), and a photoinitiator (C), The weight average of the said urethane (meth) acrylate (A) The molecular weight is in the range of 7,000 to 20,000, the average number of functional groups is in the range of 0.5 to 1.5, and the content of the (meth) acrylic monomer (B) is the urethane (meth). The present invention provides an active energy ray-curable concrete protective material in a range of 30 to 500 parts by mass with respect to 100 parts by mass of acrylate (A).

  The active energy ray curable concrete protective material of the present invention has a low viscosity, excellent workability, fast curing, and a high elongation coating film with excellent crack followability. It can be suitably used when constructing various civil engineering and building materials such as waterproofing materials for concrete.

  The concrete protective material of the present invention contains a urethane (meth) acrylate (A), a (meth) acrylic monomer (B), and a photopolymerization initiator (C), and the urethane (meth) acrylate (A). The weight average molecular weight is in the range of 7,000 to 20,000, the average number of functional groups is in the range of 0.5 to 1.5, and the (meth) acrylic monomer (B) is the urethane (meth) acrylate. (A) It is the range of 30-500 mass parts with respect to 100 mass parts.

  In the present invention, “(meth) acrylate” refers to one or both of methacrylate and acrylate, and “(meth) acrylic monomer” refers to one or both of acrylic monomer and methacrylic monomer. “(Meth) acryloyl” means one or both of acryloyl and methacryloyl, and “(meth) acrylic compound” means one or both of an acrylic compound and a methacrylic compound.

  In the present invention, the average number of functional groups of the urethane (meth) acrylate (A) is a value obtained by dividing the weight average molecular weight by the (meth) acryloyl group equivalent.

  Examples of the urethane (meth) acrylate (A) include those obtained by reacting polyol (a1), polyisocyanate (a2), and (meth) acrylic compound (a3) having a hydroxyl group or an isocyanate group. Can be used.

  As said polyol (a1), polyether polyol, polyester polyol, polycarbonate polyol, acrylic polyol, polybutadiene polyol etc. can be used, for example. These polyols may be used alone or in combination of two or more. Among these, it is preferable to use a polyether polyol because the crack followability can be further improved.

  Examples of the polyether polyol include a product obtained by addition polymerization of one or more alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide to a compound having two or more active hydrogens, and tetrahydrofuran. Polytetramethylene glycol obtained by ring-opening polymerization, modified polytetramethylene glycol copolymerized with tetrahydrofuran and alkyl-substituted tetrahydrofuran, modified polytetramethylene glycol copolymerized with neopentyl glycol and tetrahydrofuran, etc. it can.

  Examples of the compound having two or more active hydrogens include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1 , 2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,5-hexanediol, 1,6-hexanediol, 2, 5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 2-methyl -1,3-propanediol, neopentyl glycol 2-butyl-2-ethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2- Relatively low molecular weight dihydroxy compounds such as ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, hydroquinone, resorcin, bisphenol A, bisphenol F, 4,4′-bisphenol, 1,2- Cyclobutanediol, 1,3-cyclopentanediol, 1,4-cyclohexanediol, cycloheptanediol, cyclooctanediol, 1,4-cyclohexanedimethanol, hydroxypropylcyclohexanol, tricyclo [5,2,1,0,2 , 6] decane-dimethanol, bicyclo [4,3,0] Nonanediol, dicyclohexanediol, tricyclo [5,3,1,1] dodecanediol, bicyclo [4,3,0] nonanedimethanol, tricyclo [5,3,1,1] dodecane-diethanol, hydroxypropyltricyclo [5,3,1,1] dodecanol, spiro [3,4] octanediol, butylcyclohexanediol, 1,1′-bicyclohexylidenediol, cyclohexanetriol, hydrogenated bisphenol A, 1,3-adamantanediol For example, alicyclic polyol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol and other polyether polyols; polyhexamethylene adipate, polyhexamethylene succinate, polycaprolactone and other polyester polyols Can be.

  The number average molecular weight of the polyol (a1) is preferably in the range of 200 to 10,000, and more preferably in the range of 400 to 5,000 because flexibility and the like are further improved.

  The average molecular weight in this invention shows the value measured by the gel permeation chromatography (GPC) method.

  Examples of the polyisocyanate (a2) include aromatic diisocyanates such as xylylene diisocyanate, phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate; hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, 4,4 ′. Aliphatic such as dicyclohexylmethane diisocyanate, 1,2-bis (isocyanatomethyl) cyclohexane, 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, tetramethylxylylene diisocyanate Alternatively, diisocyanate having an alicyclic structure can be used. These polyisocyanates may be used alone or in combination of two or more. Among these, it is preferable to use a diisocyanate having an aliphatic or alicyclic structure because it is difficult to yellow.

  The (meth) acrylic compound (a3) having a hydroxyl group or an isocyanate group is used for the purpose of introducing a (meth) acryloyl group into the urethane (meth) acrylate (A).

  Examples of the (meth) acrylic compound having a hydroxyl group that can be used as the compound (a3) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (Meth) acrylic acid alkyl ester having a hydroxyl group such as 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, hydroxyethylacrylamide; trimethylolpropane di (meth) Polyfunctional (meth) acrylates having hydroxyl groups such as acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate; polyethylene glycol monoacrylate, poly Propylene glycol monoacrylate may be used. Among these, since it is excellent in reactivity, it is preferable to use an alkyl acrylate ester having a hydroxyl group, and it is more preferable to use 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, or hydroxyethyl acrylamide.

  Examples of the (meth) acrylic compound having an isocyanate group that can be used as the compound (a3) include 2- (meth) acryloyloxyethyl isocyanate and 2- (2- (meth) acryloyloxyethyloxy) ethyl. Isocyanate, 1,1-bis ((meth) acryloyloxymethyl) ethyl isocyanate and the like can be used. Among these, it is preferable to use 2- (meth) acryloyloxyethyl isocyanate, and 2-acryloyloxyethyl isocyanate is more preferable because the reactivity and photocurability of isocyanate are further improved.

  As a manufacturing method of the said urethane (meth) acrylate (A) in the case of using the (meth) acryl compound which has a hydroxyl group as the said compound (a3), the said polyol (a1) and the said (meth) under solvent-free, for example. A method in which an acrylic compound (a3) is charged into a reaction system and then the polyisocyanate (a2) is supplied, mixed, and reacted, or the polyol (a1) and the polyisocyanate are prepared without solvent. A urethane prepolymer having an isocyanate group is obtained by reacting with (a2), then the (meth) acrylic compound (a3) having a hydroxyl group is supplied, mixed, and reacted to be used. Can do. In any case, the reaction is preferably performed at 20 to 120 ° C. for 30 minutes to 24 hours.

  Moreover, as a manufacturing method of urethane (meth) acrylate (A) when using the (meth) acrylic compound which has an isocyanate group as said compound (a3), for example, under the absence of a solvent, the said polyol (a1) and the said poly A method for producing a urethane prepolymer having a hydroxyl group by charging and reacting with isocyanate (a2), then supplying the (meth) acrylic compound (a3) having an isocyanate group, mixing and reacting, etc. Can be used. In any case, the reaction is preferably performed at 20 to 120 ° C. for 30 minutes to 24 hours.

  The urethane (meth) acrylate (A) may be produced in the presence of an organic solvent.

  When the (meth) acrylic compound having a hydroxyl group is used as the compound (a3), the reaction of the polyol (a1), the polyisocyanate (a2), and the (meth) acrylic compound (a3) The equivalent number of hydroxyl groups (NCO) of the isocyanate groups in a2), the equivalent number of hydroxyl groups in the polyol (a1) and the equivalent number of hydroxyl groups in the (meth) acrylic compound (a3) ( It is preferable that the equivalent ratio [(NCO) / (OH)] to OH) is in the range of 0.75 to 1 in terms of controlling the molecular weight of the urethane (meth) acrylate (A) to be obtained. When the equivalent ratio [(NCO) / (OH)] exceeds 1, it is preferable to use an alcohol such as methanol for the purpose of deactivating the isocyanate group of the urethane (meth) acrylate (A). .

  Moreover, when manufacturing urethane (meth) acrylate (A), you may use a polymerization inhibitor, a urethanization catalyst, etc. as needed.

  Examples of the polymerization inhibitor include 3,5-bistertiary butyl-4-hydroxytoluene, hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether (methoquinone), 4-tertiary butyl catechol methoxyphenol, 2,6-ditertiary butyl. Cresol, phenothiazine, tetramethylthiuram disulfide, diphenylamine, dinitrobenzene and the like can be used.

  Examples of the urethanization catalyst include nitrogen-containing compounds such as triethylamine, triethylenediamine, and N-methylmorpholine; metal salts such as potassium acetate, zinc stearate, and tin octylate; dibutyltin laurate, zirconium tetraacetylacetonate, and the like. These organometallic compounds can be used.

  The urethane (meth) acrylate (A) has a (meth) acryloyl group that promotes radical polymerization by light irradiation, heating, or the like. As a (meth) acryloyl group equivalent of the said urethane (meth) acrylate (A), the range of 5,000-40,000 g / eq is preferable from the point which can make low viscosity and a softness | flexibility compatible, 6,000-30, A range of 000 g / eq is more preferred. The (meth) acryloyl group equivalent is the total mass of the polyol (a-1), the polyisocyanate (a-2) and the (meth) acrylic compound (a-3), and the urethane (meth). The value divided by the equivalent of the (meth) acryloyl group present in the acrylate (A) is shown.

  The weight average molecular weight of the urethane (meth) acrylate (A) is in the range of 7,000 to 20,000 because it can exhibit excellent curability and film flexibility at low viscosity, but it is good at lower viscosity. The workability is preferably in the range of 7,000 to 18,000.

  The average number of functional groups of the urethane (meth) acrylate (A) is in the range of 0.5 to 1.5 because it can exhibit excellent curability and coating flexibility with low viscosity, but 0.5 to 1 A range of .3 is preferred.

  Examples of the (meth) acrylic monomer (B) include isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) ) (Meth) acrylic monomers having an alicyclic structure such as acrylate and dicyclopentenyloxyethyl (meth) acrylate; 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-ethyl Ruhexyl (meth) acrylate, heptyl (meth) acrylate, n-octyl (meth) acrylate, nonyl (meth) acrylate, dodecyl (meth) acrylate, 3-methylbutyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) Aliphatic (meth) acrylic monomers such as acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, neopentyl (meth) acrylate, hexadecyl (meth) acrylate, isoamyl (meth) acrylate; 3-methoxybutyl (meth) Acrylate), 2-methoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 2-methoxybutyl (meth) acrylate, and methoxy having an addition mole number of oxyethylene in the range of 1-15. (Meth) acrylic monomers having ether groups such as polyethylene glycol acrylate, ethoxy-diethylene glycol (meth) acrylate, ethyl carbitol (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) (Meth) acrylic monomers having a hydroxyl group such as acrylate and 4-hydroxybutyl (meth) acrylate; benzyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol acrylate, phenyl (meth) ) Aromatic (meth) acrylic monomers such as acrylate and 2-hydroxy-3-phenoxypropyl (meth) acrylate; (meth) acrylamide, dimethyl (meth) acrylamide, a Use (meth) acrylic monomers having nitrogen atoms such as acryloylmorpholine, dimethylaminopropyl (meth) acrylamide, isopropyl (meth) acrylamide, diethyl (meth) acrylamide, diacetone (meth) acrylamide, hydroxyethyl acrylamide, etc. be able to. These (meth) acrylic monomers may be used alone or in combination of two or more.

  The amount of the (meth) acrylic monomer (B) used can be 30% with respect to 100 parts by mass of the urethane (meth) acrylate (A) because it exhibits low viscosity and excellent curability and coating flexibility. Although it is the range of -500 mass parts, the range of 50-400 mass parts is preferable, and the range of 80-300 mass parts is more preferable.

  Examples of the photopolymerization initiator (C) include 4-phenoxydichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 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) Acetophenone compounds such as phenyl] -2-morpholino-1-propanone and 2,2-dimethoxy-2-phenylacetophenone; benzoin compounds such as benzoin, benzoin methyl ether, benzoin isoethyl ether, benzoin isopropyl ether and 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, 2- Thioxanthone compounds such as chlorothioxanthone, 2,4-dichlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone; 4,4′-dimethylamino Thioxanthone (also known as Minerals ketone), 4,4′-diethylaminobenzophenone, α-acyloxime ester, benzyl, methylbenzoylformate (“ Viacure 55 "), anthraquinone compounds such as 2-ethylanthraquinone; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide 3,3 ′, 4,4′-tetra (tert-butyloperoxycarbonyl) benzophenone, acrylated benzophenone, and the like can be used.

  As the photopolymerization initiator (C), since curability is further improved, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,4,6- Trimethylbenzoyldiphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide are preferably used.

  Since the usage-amount of the said photoinitiator (C) improves the balance of sclerosis | hardenability and coating-film flexibility, the said urethane (meth) acrylate (A) and the said (meth) acryl monomer (B) The range of 0.01 to 20 parts by mass is preferable, the range of 0.05 to 15 parts by mass is more preferable, and the range of 0.1 to 10 parts by mass is particularly preferable.

  The active energy ray-curable concrete protective material of the present invention contains the urethane (meth) acrylate (A), the (meth) acrylic monomer (B), and the photopolymerization initiator (C) as essential components. However, it may contain other additives as required.

  Examples of the other additives include polymerization inhibitors, antioxidants, light stabilizers, solvents, rust inhibitors, thixotropic agents, sensitizers, leveling agents, tackifiers, antistatic agents, and flame retardant curing. Agents, curing accelerators, pigments, fillers, reinforcing materials, aggregates, petroleum waxes and the like.

  The active energy rays for curing the active energy ray-curable concrete protective material of the present invention are ionizing radiations such as ultraviolet rays, electron beams, α rays, β rays, and γ rays. For example, germicidal lamps, fluorescent lamps for ultraviolet rays, carbon arc, xenon lamps, high pressure mercury lamps for copying, medium or high pressure mercury lamps, ultrahigh pressure mercury lamps, electrodeless lamps, metal halide lamps, fluorescent chemical lamps, natural light, etc. Or an electron beam by a scanning type or curtain type electron beam accelerator.

  The protective material for active energy ray-curable concrete of the present invention can be used as a protective material for concrete such as cement concrete, asphalt concrete, mortar concrete, resin concrete, permeable concrete, ALC (Autoclaved Lightweight Aerated Concrete) plate, and the like. .

  The active energy ray-curable concrete protective material of the present invention is suitably used for construction of various civil engineering and building materials such as concrete repair materials and waterproofing materials because a coating film having excellent curability and excellent flexibility can be obtained. be able to.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. The average molecular weight is measured under the following GPC measurement conditions.

[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.
"TSKgel G5000" (7.8 mm ID x 30 cm) x 1 "TSKgel G4000" (7.8 mm ID x 30 cm) x 1 "TSKgel G3000" (7.8 mm ID x 30 cm) x 1 “TSKgel G2000” (7.8 mm ID × 30 cm) × 1 detector: RI (differential refractometer)
Column temperature: 40 ° C
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 mL / min Injection amount: 100 μL (tetrahydrofuran solution with a sample concentration of 4 mg / mL)
Standard sample: A calibration curve was prepared using the following monodisperse polystyrene.

(Monodispersed 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

(Synthesis Example 1: Synthesis of urethane (meth) acrylate (A-1))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 85.5 parts by mass of polyoxypropylene glycol having a number average molecular weight of 3000 (hereinafter abbreviated as “PPG3000”) and a number average molecular weight of 1,000. Polytetramethylene glycol (hereinafter abbreviated as “PTMG1000”) 400.2 parts by mass, number average molecular weight 400 polyethylene glycol (hereinafter abbreviated as “PEG400”) 103.0 parts by mass, 2-hydroxyethyl Acrylate (hereinafter abbreviated as “HEA”) 8.5 parts by mass, 2,6-ditertiarybutyl-cresol (hereinafter abbreviated as “BHT”) 1.5 parts by mass, p-methoxy 0.2 parts by weight of phenol was added. After raising the temperature in the reaction vessel to 40 ° C., 98.8 parts by mass of isophorone diisocyanate (hereinafter abbreviated as “IPDI”) was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 13,000g / eq, weight average molecular weight 13,500, and average functional group number 1.04. Urethane (meth) acrylate (A-1) was obtained.

(Synthesis Example 2: Synthesis of urethane (meth) acrylate (A-2))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 85.1 parts by mass of PPG3000, 200.2 parts by mass of PTMG1000, 103.9 parts by mass of PEG400, 6.4 parts by mass of HEA, BHT 5 parts by mass and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 97.6 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintains at 80 degreeC for 12 hours, It cools, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 13,000g / eq, weight average molecular weight 10,000, average functional group number 0.76. Urethane (meth) acrylate (A-2) was obtained.

(Synthesis Example 3: Synthesis of urethane (meth) acrylate (A-3))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 77.9 parts by mass of PPG3000, 205.7 parts by mass of PTMG1000, 98.2 parts by mass of PEG400, 6.3 parts by mass of HEA, BHT 5 parts by mass and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 102.8 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 9,000 g / eq, weight average molecular weight 13,500, and average functional group number 1.33. Urethane (meth) acrylate (A-3) was obtained.

(Synthesis Example 4: Synthesis of urethane (meth) acrylate (A-4))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 916.8 parts by mass of polyoxypropylene glycol having a number average molecular weight of 2000 (hereinafter abbreviated as “PPG2000”), HEA 9.1. Part by mass, 1.5 parts by mass of BHT, and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 93.2 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 13,000g / eq, weight average molecular weight 13,500, and average functional group number 1.04. Urethane (meth) acrylate (A-4) was obtained.

(Synthesis Example 5: Synthesis of urethane (meth) acrylate (A-5))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 1042.2 parts by mass of hydrogenated polybutadiene polyol having a number average molecular weight of 2000 (hereinafter abbreviated as “GI-2000”), HEA 10 0.2 parts by weight, 1.5 parts by weight of BHT, and 0.2 parts by weight of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 90.8 parts by mass of IPDI was added. Therefore, 0.01 parts by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 13,000g / eq, weight average molecular weight 13,500, and average functional group number 1.04. Urethane (meth) acrylate (A-5) was obtained.

(Synthesis Example 6: Synthesis of urethane (meth) acrylate (A-6))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 915.3 parts by mass of a polyester polyol having a number average molecular weight of 2000 (hereinafter abbreviated as “P-2010”), HEA 9.1. Part by mass, 1.5 parts by mass of BHT, and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 93.3 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 13,000g / eq, weight average molecular weight 13,500, and average functional group number 1.04. Urethane (meth) acrylate (A-6) was obtained.

(Synthesis Example 7: Synthesis of urethane (meth) acrylate (A-7))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 82.0 parts by mass of PPG3000, 208.8 parts by mass of PTMG1000, 99.9 parts by mass of PEG400, 3.6 parts by mass of HEA, BHT1. 5 parts by mass and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 104.5 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 16,346g / eq, weight average molecular weight 20,000, average functional group number 1.04. Urethane (meth) acrylate (A-7) was obtained.

(Synthesis Example 8: Synthesis of urethane (meth) acrylate (A-8))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 82.4 parts by mass of PPG3000, 209.8 parts by mass of PTMG1000, 101.1 parts by mass of PEG400, 3.0 parts by mass of HEA, BHT 5 parts by mass and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 105.5 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintains at 80 degreeC for 12 hours, It cools, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 19,230g / eq, weight average molecular weight 20,000, average functional group number 1.04. Urethane (meth) acrylate (A-8) was obtained.

(Synthesis Example 9: Synthesis of urethane (meth) acrylate (RA-1))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 78.5 parts by mass of PPG3000, 199.9 parts by mass of PTMG1000, 96.4 parts by mass of PEG400, 8.4 parts by mass of HEA, BHT 5 parts by mass and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 102.8 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintained at 80 degreeC for 12 hours, it cooled, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 6,750g / eq, weight average molecular weight 13,500, and average functional group number 1.60. Urethane (meth) acrylate (RA-1) was obtained.

(Synthesis Example 10: Synthesis of urethane (meth) acrylate (RA-2))
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 81.3 parts by mass of PPG 3000, 207.2 parts by mass of PTMG 1000, 99.8 parts by mass of PEG 400, 4.5 parts by mass of HEA, BHT 5 parts by mass and 0.2 parts by mass of p-methoxyphenol were added. After raising the temperature in the reaction vessel to 40 ° C., 105.8 parts by mass of IPDI was added. Therefore, 0.01 part by mass of dioctyltin dineodecanate was added, and the temperature was raised to 80 ° C. over 1 hour. Then, it hold | maintains at 80 degreeC for 12 hours, It cools, after confirming that all the isocyanate groups have lose | disappeared, acryloyl group equivalent 13,000g / eq, weight average molecular weight 21,000, and average functional group number 1.62. Urethane (meth) acrylate (RA-2) was obtained.

(Example 1: Preparation and evaluation of active energy ray-curable concrete protective material (1))
In a light-shielding container equipped with a stirrer, a reflux condenser, and a thermometer, 40 parts by mass of urethane (meth) acrylate (A-1) obtained in Synthesis Example 1 and normal octyl acrylate (hereinafter abbreviated as “nOA”) 45. Part by mass, 15 parts by mass of acryloylmorpholine (hereinafter abbreviated as “ACMO”), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (hereinafter abbreviated as “photopolymerization initiator (C-1)”). ) 1.5 parts by mass, bis (2,2,6,6-tetramethyl-1- (octyloxy) -4-piperidinyl) ester 0.5 parts by mass, triphenylphosphine 0.5 parts by mass, 0.1 part by mass of 3-glycidoxypropyltriethoxysilane was added and stirred at 80 ° C. until uniform. Then, it filtered with a 200 mesh wire mesh, and obtained the active energy ray hardening-type concrete protective material (1).

[Evaluation of viscosity]
The active energy ray-curable concrete protective material (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 2,000 mPa · s ×: 2,000 mPa · s or more

[Evaluation of alkali resistance]
An active energy ray-curable concrete protective material (1) was applied on the concrete mortar so that the film thickness was 500 μm, and then irradiated with a fluorescent chemical lamp (3 mW) for 5 minutes to obtain a test specimen. The test specimen was immersed in a saturated calcium hydroxide aqueous solution at 40 ° C. for half a day for 30 days, and then the presence or absence of a change in the coating film appearance was evaluated.
○: No change ×: Swelling

[Measurement of gel fraction]
On the peeled PET film, the active energy ray-curable concrete protective material (1) was applied so as to have a film thickness of 500 μm, and then irradiated with a fluorescent chemical lamp (3 mW) for 5 minutes to obtain a cured coating film. This cured coating film was processed to 50 × 10 mm and immersed in toluene for 24 hours. After soaking, it was dried at 80 ° C. for 4 hours, the gel fraction (%) was calculated by the following formula, and the curability was evaluated according to the following criteria.
Gel fraction (%) = (mass of coating film after immersion in toluene / mass of coating film before immersion in toluene) × 100 (%)
○: Gel fraction is 50% or more ×: Gel fraction is less than 50%

[Measurement of tensile elongation]
The active energy ray-curable concrete protective material (1) obtained above is 175 μm in film thickness after UV irradiation on the surface of a 50 μm thick polyethylene terephthalate film (release PET 50) whose surface has been released. It applied so that it might become, and release PET50 was bonded together. Thereafter, UV irradiation was performed with a UV irradiation apparatus so that the integrated light quantity of the wavelength in the UV-A region after passing through the release PET 50 was 1000 mJ / cm ² to prepare a coating film.
About the coating film obtained above, based on JISK6911, the tension test was implemented and the softness | flexibility was evaluated by the following reference | standard.
○: Elongation is 1000% or more ×: Elongation is less than 1000%

[Evaluation of crack followability]
After applying the active energy ray-curable concrete protective material (1) obtained above to a 120 × 70 × 10 mm (notched) mortar plate so as to have a film thickness of 500 μm, an illuminance of 3. A test specimen for evaluation was obtained by irradiating 0 mW ultraviolet ray for 5 minutes. The test specimen was evaluated for crack followability in accordance with JSCE-K-532. The displacement (mm) from the start of the test until the coating film started to break was measured, and the crack followability was evaluated according to the following criteria.
○: Displacement amount is 5 mm or more ×: Displacement amount is less than 5 mm

(Examples 2 to 8: Preparation and evaluation of active energy ray-curable concrete protective materials (2) to (8))
Active energy rays in the same manner as in Example 1 except that the urethane (meth) acrylate (A-1) used in Example 1 was changed to urethane (meth) acrylates (A-2) to (A-8). After preparing the curable concrete protective materials (2) to (8), each physical property was evaluated.

(Examples 9 to 13: Preparation and evaluation of active energy ray-curable concrete protective materials (9) to (13))
Active energy ray curable concrete as in Example 1 except that the urethane (meth) acrylate, (meth) acrylic monomer, and photopolymerization initiator used in Example 1 were changed as shown in Table 2. After preparing the protective materials (9) to (13), each physical property was evaluated.

(Comparative Examples 1-4: Preparation and evaluation of active energy ray-curable concrete protective materials (R1) to (R4))
The active energy ray-curable concrete protective material (R1) was the same as in Example 1 except that the urethane (meth) acrylate and (meth) acrylic monomer used in Example 1 were changed as shown in Table 3. Each physical property was evaluated after preparing (R4).

  Tables 1 to 3 show the compositions and evaluation results of the active energy ray-curable concrete protective materials (1) to (13) and (R1) to (R4) obtained above.

The abbreviations in the above table are as follows.
“IBXA”: isobornyl acrylate “CHA”: cyclohexyl acrylate “C-2”: 1-hydroxycyclohexyl phenyl ketone

  It was confirmed that the concrete protective materials of the present invention of Examples 1 to 13 have a low viscosity, excellent workability, excellent quick curability, and excellent flexibility.

  Although the comparative example 1 is an example in which the average functional group number of urethane (meth) acrylate exceeds the upper limit of 1.5, it was confirmed that the crack followability of the obtained coating film was insufficient.

  Comparative Example 2 is an example in which the weight average molecular weight of urethane (meth) acrylate exceeds the upper limit of 20,000, but was confirmed to have high viscosity.

  Although the comparative example 3 is an example in which the mass% of the (meth) acrylic monomer (B) with respect to the urethane (meth) acrylate (A) exceeds the upper limit of 500 mass%, the gel fraction ( Curability) and alkali resistance were confirmed to be insufficient.

  Although the comparative example 4 is an example whose mass% of the (meth) acrylic monomer (B) with respect to urethane (meth) acrylate (A) is less than 30 mass% which is a minimum, it was confirmed that it is high viscosity. .

Claims (2)

  It contains urethane (meth) acrylate (A), (meth) acrylic monomer (B), and photopolymerization initiator (C), and the urethane (meth) acrylate (A) has a weight average molecular weight of 7,000 to The range of 20,000, the average number of functional groups is in the range of 0.5 to 1.5, and the content of the (meth) acrylic monomer (B) is 100 masses of the urethane (meth) acrylate (A). The active energy ray-curable concrete protective material is in a range of 30 to 500 parts by mass with respect to parts.   The photopolymerization initiator (C) is in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass in total of the urethane (meth) acrylate (A) and the (meth) acrylic monomer (B). The active energy ray-curable concrete protective material according to claim 1.