Concrete primer

Abstract

To provide a primer for concrete that can give a coating layer having excellent curability, wet surface adhesion and adhesion to asphalt.SOLUTION: A primer for concrete contains a resin (A) having a polymerizable unsaturated group at each end, a methacryl monomer (B), a cyclodextrin derivative (C), and a tackifier (D). The content of the tackifier (D) is 1-50 mass%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a primer for concrete. [Background technology]

[0002] Recently, the premature deterioration of road bridge decks, including those on expressways, has become noticeable due to increasing traffic loads and the spraying of antifreeze.The mechanism of this premature deterioration is thought to be that rainwater, antifreeze, etc. penetrate into the structure through cracks that have appeared in the asphalt pavement and reinforced concrete deck, corroding the reinforcing bars and reducing the durability of the structure.

[0003] Therefore, waterproofing systems including a waterproofing layer installed between concrete and asphalt have been studied, and a radical polymerizable resin composition containing an air-drying unsaturated resin, a radical polymerizable monomer, and cyclodextrin and / or a derivative thereof has been proposed as such a material (see, for example, Patent Document 1).

[0004] However, although this material has excellent wet surface adhesion, there is a problem with adhesion to asphalt. Therefore, there is a need for a material that can produce a coating film that is excellent in curing properties, wet surface adhesion properties, and adhesion to asphalt. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6066027 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved by the present invention is to provide a primer for concrete which gives a coating film that is excellent in curability, wet surface adhesion, and adhesion to asphalt. [Means for solving the problem]

[0007] As a result of extensive research into solving the above-mentioned problems, the present inventors have found that a concrete primer containing a resin (A) having polymerizable unsaturated groups at both ends, a (meth)acrylic monomer (B), a cyclodextrin derivative (C), and a tackifier (D) can solve the above-mentioned problems, and have thus completed the present invention.

[0008] That is, the present invention provides a primer for concrete, characterized by containing a resin (A) having polymerizable unsaturated groups at both ends, a (meth)acrylic monomer (B), a cyclodextrin derivative (C), and a tackifier (D). [Effects of the Invention]

[0009] The concrete primer of the present invention can be suitably used as a primer for various types of concrete because it can provide a coating film that is excellent in curing properties, wet surface adhesion, and asphalt adhesion resistance. DETAILED DESCRIPTION OF THE INVENTION

[0010] The concrete primer of the present invention contains a resin (A) having polymerizable unsaturated groups at both ends, a (meth)acrylic monomer (B), a cyclodextrin derivative (C), and a tackifier (D).

[0011] In the present invention, the term "(meth)acrylic monomer" refers to either or both of an acrylic monomer and a methacrylic monomer, the term "(meth)acrylate" refers to either or both of a methacrylate and an acrylate, and the term "(meth)acryloyl" refers to either or both of an acryloyl and a methacryloyl.

[0012] Examples of the resin (A) having polymerizable unsaturated groups at both ends include epoxy (meth)acrylate, polyester (meth)acrylate, and urethane (meth)acrylate. These resins (A) having polymerizable unsaturated groups at both ends may be used alone or in combination of two or more.

[0013] The epoxy (meth)acrylate may be, for example, a compound obtained by reacting a bisphenol-type epoxy compound or an epoxy compound obtained by mixing a bisphenol-type epoxy compound with a novolac-type epoxy compound with an unsaturated monobasic acid by a conventionally known method.

[0014] Examples of the bisphenol-type epoxy compound that can be used include a glycidyl ether-type epoxy compound having two or more epoxy groups per molecule obtained by reacting epichlorohydrin with bisphenol A or bisphenol F, a dimethylglycidyl ether-type epoxy compound obtained by reacting methylepichlorohydrin with bisphenol A or bisphenol F, and an epoxy compound obtained by reacting an alkylene oxide adduct of bisphenol A with epichlorohydrin or methylepichlorohydrin. These epoxy compounds may be used alone or in combination of two or more.

[0015] The novolac-type epoxy compound may be, for example, an epoxy compound obtained by reacting phenol novolac or cresol novolac with epichlorohydrin or methyl epichlorohydrin. These epoxy compounds may be used alone or in combination of two or more.

[0016] Examples of the unsaturated monobasic acid that can be used include (meth)acrylic acid, cinnamic acid, crotonic acid, monomethyl maleate, monopropyl maleate, monobutene maleate, sorbic acid, mono(2-ethylhexyl) maleate, etc. These unsaturated monobasic acids may be used alone or in combination of two or more.

[0017] The polyester (meth)acrylate may be, for example, a saturated polyester or an unsaturated polyester having two or more (meth)acryloyl groups in one molecule. The saturated polyester is obtained by a condensation reaction between a saturated dibasic acid and a polyhydric alcohol, and the unsaturated polyester is obtained by a condensation reaction between an α,β-unsaturated dibasic acid and a polyhydric alcohol, both of which have a (meth)acryloyl group at the terminal.

[0018] The saturated dibasic acid, α,β-unsaturated dibasic acid, and polyhydric alcohol may be the same as those used in the synthesis of the unsaturated polyester (B) described below.

[0019] The polyester (meth)acrylate may be produced by reacting a saturated polyester or an unsaturated polyester with glycidyl (meth)acrylate by a known method.

[0020] The urethane (meth)acrylate may be, for example, one obtained by reacting a polyol, a polyisocyanate, and a (meth)acrylic compound having a hydroxyl group or an isocyanate group by a conventionally known method.

[0021] Examples of the polyol that can be used include polyester polyol, polycarbonate polyol, polyether polyol, acrylic polyol, caprolactone polyol, butadiene polyol, etc. These polyols may be used alone or in combination of two or more.

[0022] Examples of the polyisocyanate that can be used include aromatic diisocyanates such as phenylene diisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate, and naphthalene diisocyanate; aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, xylylene diisocyanate, and tetramethylxylylene diisocyanate; and aromatic polyisocyanates such as xylylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, polyphenylene polymethylene polyisocyanate, formalin condensates of methylene diphenyl diisocyanate, and carbodiimide-modified 4,4'-diphenylmethane diisocyanate. These polyisocyanates may be used alone or in combination of two or more.

[0023] Examples of the (meth)acrylic compound having a hydroxyl group that can be used include (meth)acrylic acid alkyl esters having a hydroxyl group, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; polyethylene glycol monoacrylate; and polypropylene glycol monoacrylate. These compounds may be used alone or in combination of two or more.

[0024] Examples of the (meth)acrylic compound having an isocyanate group that can be used include 2-(meth)acryloyloxyethyl isocyanate, 2-(2-(meth)acryloyloxyethyloxy)ethyl isocyanate, 1,1-bis((meth)acryloyloxymethyl)ethyl isocyanate, etc. These compounds may be used alone or in combination of two or more.

[0025] The number average molecular weight of the resin (A) is preferably 500 to 4,000, as this allows for further improvement in workability and curability.

[0026] The content of the resin (A) in the primer for concrete is preferably 20 to 60 mass %, more preferably 30 to 50 mass %, since this allows for further improvement in curability.

[0027] Examples of the (meth)acrylic monomer (B) include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, decyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, β-ethoxyethyl (meth)acrylate, 2-cyanoethyl (meth)acrylate, cyclohexyl (meth)acrylate, dimethicone, methyl (meth)acrylate ... Examples of monomers that can be used include ethylaminoethyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, polycaprolactone (meth)acrylate, diethylene glycol monomethyl ether mono(meth)acrylate, dipropylene glycol monomethyl ether mono(meth)acrylate, 2-ethylhexyl carbitol (meth)acrylate, tris(2-hydroxyethyl)isocyanuric (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and phenoxyethyl (meth)acrylate. These monomers may be used alone or in combination of two or more.

[0028] The content of the (meth)acrylic monomer (B) in the concrete primer is 10 to 50 mass %, more preferably 20 to 50 mass %, and even more preferably 30 to 50 mass %, because excellent curing properties can be achieved with low viscosity.

[0029] Examples of the cyclodextrin derivative (C) include cyclodextrin; alkylated cyclodextrin, acetylated cyclodextrin, and hydroxyalkylated cyclodextrin, in which the hydrogen atoms of the hydroxyl groups of the glucose units of cyclodextrin are substituted with other functional groups. Furthermore, the cyclodextrin skeleton in the cyclodextrin and cyclodextrin derivatives may be any of α-cyclodextrin consisting of six glucose units, β-cyclodextrin consisting of seven glucose units, and γ-cyclodextrin consisting of eight glucose units. These cyclodextrin derivatives (C) may be used alone or in combination of two or more. Among these, methylated β-cyclodextrin is preferred due to its excellent solubility in resins.

[0030] The content of the cyclodextrin derivative (C) in the concrete primer is preferably 0.1 to 5 mass %, more preferably 0.2 to 3 mass %, since this further improves wet surface adhesion and adhesion to asphalt.

[0031] Examples of the tackifier (D) include petroleum resins, terpene resins, and styrene resins.

[0032] The content of the tackifier (D) in the concrete primer is preferably 1 to 50 mass %, more preferably 3 to 40 mass %, since this further improves wet surface adhesion and adhesion to asphalt.

[0033] The concrete primer of the present invention contains a resin (A) having polymerizable unsaturated groups at both ends, a (meth)acrylic monomer (B), a cyclodextrin derivative (C), and a tackifier (D), and may also contain other additives, etc., as needed.

[0034] Examples of the other additives include polymerization initiators, polymerization inhibitors, antioxidants, light stabilizers, solvents, rust inhibitors, sensitizers, leveling agents, rheology control agents, tackifiers, antistatic agents, flame retardants, curing agents, curing accelerators, pigments, fillers, reinforcing materials, aggregates, and petroleum waxes.

[0035] The concrete primer of the present invention can be used as a primer for concrete such as cement concrete, asphalt concrete, mortar concrete, resin concrete, permeable concrete, and ALC (Autoclaved Lightweight Aerated Concrete) board. [Example]

[0036] The present invention will be described in more detail below with reference to specific examples. The acid value was measured in accordance with JIS-K-6901, and the average molecular weight was measured under the following GPC measurement conditions.

[0037] [GPC measurement conditions] Measurement equipment: High-speed GPC equipment (Tosoh Corporation "HLC-8220GPC") Column: The following columns manufactured by Tosoh Corporation were connected in series and used. "TSKgel G5000" (7.8mm I.D. x 30cm) x 1 "TSKgel G4000" (7.8mm I.D. x 30cm) x 1 "TSKgel G3000" (7.8mm I.D. x 30cm) x 1 "TSKgel G2000" (7.8mmI.D. x 30cm) x 1 Detector: RI (differential refractometer) Column temperature: 40℃ Eluent: tetrahydrofuran (THF) Flow rate: 1.0mL / min Injection volume: 100 μL (sample concentration 4 mg / mL in tetrahydrofuran solution) Standard sample: A calibration curve was prepared using the following monodisperse polystyrene.

[0038] (monodisperse polystyrene) Tosoh Corporation's "TSKgel Standard Polystyrene A-500" Tosoh Corporation's "TSKgel Standard Polystyrene A-1000" Tosoh Corporation's "TSKgel Standard Polystyrene A-2500" Tosoh Corporation's "TSKgel Standard Polystyrene A-5000" "TSKgel Standard Polystyrene F-1" manufactured by Tosoh Corporation Tosoh Corporation's "TSKgel Standard Polystyrene F-2" Tosoh Corporation's "TSKgel Standard Polystyrene F-4" Tosoh Corporation's "TSKgel Standard Polystyrene F-10" Tosoh Corporation's "TSKgel Standard Polystyrene F-20" Tosoh Corporation's "TSKgel Standard Polystyrene F-40" Tosoh Corporation's "TSKgel Standard Polystyrene F-80" Tosoh Corporation's "TSKgel Standard Polystyrene F-128" Tosoh Corporation's "TSKgel Standard Polystyrene F-288" Tosoh Corporation's "TSKgel Standard Polystyrene F-550"

[0039] (Synthesis Example 1: Synthesis of Resin (A-1) Having Polymerizable Unsaturated Groups at Both Ends) A four-neck flask equipped with a thermometer, a stirrer, an inert gas inlet, and a reflux condenser was charged with 1,850 parts by mass of Epiclon 850 (manufactured by DIC Corporation), which is an epoxy equivalent obtained by reacting bisphenol A with epichlorohydrin, 860 parts by mass of acrylic acid, 1.36 parts by mass of hydroquinone, and 10.8 parts by mass of triethylamine, and the temperature was raised to 120°C. The mixture was reacted for 10 hours, yielding a resin (A-1) having polymerizable unsaturated groups at both ends as an epoxy acrylate with a molecular weight of 512 and an acid value of 3.5.

[0040] (Synthesis Example 2: Synthesis of Resin (A-2) Having Polymerizable Unsaturated Groups at Both Ends) A four-neck flask equipped with a thermometer, a stirrer, an inert gas inlet, and a reflux condenser was charged with 250 parts by mass of neopentyl glycol, 100 parts by mass of propylene glycol, 390 parts by mass of adipic acid, and 100 parts by mass of maleic anhydride, and 0.5 parts by mass of monobutyltin oxide was added as an esterification catalyst, followed by a reaction for 11 hours at 205° C. The mixture was then cooled to 140° C., and 25 parts by mass of glycidyl methacrylate was added and reacted for 10 hours to obtain Resin (A-2) having polymerizable unsaturated groups at both ends as a polyester (meth)acrylate with a number average molecular weight of 4,150.

[0041] (Synthesis Example 3: Synthesis of Resin (A-3) Having Polymerizable Unsaturated Groups at Both Ends) A reaction vessel equipped with a thermometer, stirrer, inert gas inlet, air inlet, and reflux condenser was charged with 500 parts by weight of polypropylene glycol with a number average molecular weight of 1,000 and 172 parts by weight of tolylene diisocyanate, and the mixture was reacted for 2 hours at 80°C under a nitrogen stream. When the NCO equivalent reached 600, nearly the theoretical equivalent, the mixture was cooled to 50°C. Under an air stream, 0.07 parts by weight of hydroquinone and 135 parts by weight of 2-hydroxyethyl methacrylate were added, and the mixture was reacted for 4 hours at 90°C. When the NCO% reached 0.1% or less, 0.07 parts by weight of tertiary butyl catechol was added to obtain a resin (A-3) having polymerizable unsaturated groups at both ends as a urethane methacrylate with a number average molecular weight of 1,580.

[0042] (Example 1: Preparation and evaluation of concrete primer (1)) A light-shielding container equipped with a stirrer, reflux condenser, and thermometer was charged with 20 parts by weight of a resin (A-1) having polymerizable unsaturated groups at both ends, 10 parts by weight of a resin (A-2) having polymerizable unsaturated groups at both ends, 10 parts by weight of a resin (A-3) having polymerizable unsaturated groups at both ends, 0.5 parts by weight of methylated β-cyclodextrin, and 5 parts by weight of a petroleum resin ("Petrotack 90" manufactured by Tosoh Corporation; hereinafter referred to as "tackifier (D-1")). The resulting mixture was diluted with 15 parts by weight of methyl methacrylate and 25 parts by weight of 2-ethylhexyl acrylate to obtain a radically polymerizable resin composition. 0.5 parts by weight of 6% cobalt octylate and 0.4 parts by weight of para-toluidine-2-hydroxyethyl were added as curing accelerators to 100 parts by weight of this radically polymerizable resin composition to obtain a concrete primer (1).

[0043] [Preparation of evaluation samples] An evaluation sample (1) was obtained by adding 2 parts by mass of an organic peroxide ("Niper NS" manufactured by NOF Corporation) to 100 parts by mass of the concrete primer (1) obtained above.

[0044] [Evaluation of curability] The evaluation sample (1) obtained above was applied to a slate board at a pressure of 0.2 kg / m 2 The time until the composition became tack-free to the touch at 23°C was measured, and the curability was evaluated according to the following criteria. 〇: Less than 90 minutes ×: 90 minutes or more

[0045] [Evaluation of wet surface adhesion] The evaluation sample (1) obtained above was immersed in water for one day, then taken out and wiped off the water droplets on a paving board. 2 After the coating was cured for one day, it was pulled vertically using a Kenken-type tensile tester ("Technostar RT-3000LD" manufactured by Sanko Techno Co., Ltd.) to measure the peel strength, and the wet surface adhesion was evaluated according to the following criteria. 〇1.0N / mm 2 End ×1.0N / mm 2 less than

[0046] [Evaluation of adhesion to asphalt] The evaluation sample (1) obtained above was applied to a JIS concrete pavement board (300 x 300 x 60 mm) and the primer was applied with a brush at a rate of 0.20 kg / m 2 After the coating dried, 1.0 kg / m of modified asphalt type II heated to 200 °C was applied. 2 A jig was attached to the cured coating with an epoxy resin adhesive, and the coating was pulled vertically using a Kenken-type tensile testing machine ("Technostar RT-3000LD" manufactured by Sanko Techno Co., Ltd.) to measure the peel strength, and the wet surface adhesion was evaluated according to the following criteria. 〇1.0N / mm 2 End ×1.0N / mm 2 less than

[0047] (Example 2: Preparation and evaluation of concrete primer (2)) A concrete primer (2) and an evaluation sample were prepared in the same manner as in Example 1, except that the tackifier (D-1) used in Example 1 was changed to a petroleum resin ("Petrotack 100V" manufactured by Tosoh Corporation), and then the physical properties were evaluated.

[0048] (Example 3: Preparation and evaluation of concrete primer (3)) A concrete primer (3) and an evaluation sample were prepared in the same manner as in Example 1, except that the tackifier (D-1) used in Example 1 was changed to a terpene resin (YS Resin PX1250 manufactured by Yasuhara Chemical Co., Ltd.), and then the physical properties were evaluated.

[0049] (Example 4: Preparation and evaluation of concrete primer (4)) Except for changing the tackifier (D-1) used in Example 1 to a styrene resin (YS Resin SX100 manufactured by Yasuhara Chemical Co., Ltd.), a concrete primer (4) and an evaluation sample were prepared in the same manner as in Example 1, and then their physical properties were evaluated.

[0050] (Example 5: Preparation and evaluation of concrete primer (5)) A concrete primer (5) and an evaluation sample were prepared in the same manner as in Example 1, except that the 5 parts by mass of the tackifier (D-1) used in Example 1 was changed to 30 parts by mass, and then the physical properties were evaluated.

[0051] (Comparative Example 1: Preparation and Evaluation of Concrete Primer (R1)) A concrete primer (R1) and an evaluation sample were prepared in the same manner as in Example 1, except that the methylated β-cyclodextrin used in Example 1 was not used, and then the properties were evaluated.

[0052] (Comparative Example 2: Preparation and Evaluation of Concrete Primer (R2)) A concrete primer (R2) and an evaluation sample were prepared in the same manner as in Example 1, except that the tackifier (D-1) used in Example 1 was not used, and then the physical properties were evaluated.

[0053] Tables 1 and 2 show the evaluation results of the concrete primers (1) to (5) and (R1) to (R2) obtained above.

[0054] [Table 1]

[0055] [Table 2]

[0056] It was confirmed that the concrete primers of the present invention of Examples 1 to 5 gave coating films that were excellent in curing properties, wet surface adhesion, and adhesion to asphalt.

[0057] Comparative Example 1 is an example that does not contain the cyclodextrin derivative (C), and the wet surface adhesion was insufficient.

[0058] Comparative Example 2 is an example in which the tackifier (D) was not contained, and the adhesion of the resulting coating film to asphalt was insufficient.

Claims

1. A concrete primer comprising a resin (A) having polymerizable unsaturated groups at both ends, a (meth)acrylic monomer (B), a cyclodextrin derivative (C), and a tackifier (D), wherein the content of the (meth)acrylic monomer (B) is 10 to 50 mass%.

2. 2. The concrete primer according to claim 1, wherein the content of the tackifier (D) is 1 to 50 mass %.

3. 2. The concrete primer according to claim 1, wherein the resin (A) is one or more resins selected from the group consisting of epoxy (meth)acrylates, polyester (meth)acrylates, and urethane (meth)acrylates.

4. 4. The concrete primer according to claim 1, wherein the tackifier is one or more resins selected from the group consisting of petroleum resins, terpene resins, and styrene resins.

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