JP2018030990A - Adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive composition capable of forming an adhesive layer which has excellent rubber elasticity and adhesive strength and exhibits excellent planar tensile strength and peel strength even when brought into contact with alkaline moisture.SOLUTION: The adhesive composition of the present invention contains 100 pts.mass of a polyalkylene oxide (A) having a hydrolyzable silyl group, 10-100 pts.mass of a fatty acid-treated calcium oxide (B), 1-10 pts.mass of an aminosilane coupling agent (C), and a silanol condensation catalyst (D). The mass ratio of the fatty acid-treated calcium oxide (B) to the aminosilane coupling agent (C) [the mass of the fatty acid-treated calcium oxide (B)/the mass of the aminosilane coupling agent (C)] is 2-40.SELECTED DRAWING: None

Description

  The present invention relates to an adhesive composition.

  Conventionally, concrete is often used for the inner wall, outer wall, and floor surface of a building structure. In order to improve the durability and design properties of concrete, a surface finishing material (for example, an organic sheet or tile such as polyvinyl chloride) is bonded and integrated to the concrete surface via an adhesive layer.

  Patent Document 1 includes 55 to 95% by weight of a conjugated diene monomer, 4.5 to 44.5% by weight of an aromatic vinyl monomer, and 0.5 to 5 of an ethylenically unsaturated carboxylic acid monomer. A flooring material obtained by emulsion polymerization of 0% to 10% by weight and other vinyl monomers copolymerizable therewith, having a gel content of 30% by weight or less and a number average particle size of 30 nm to 130 nm A copolymer latex for aqueous adhesives is disclosed.

JP 2008-163083 A

  The above-described copolymer latex for aqueous adhesive for flooring exhibits excellent peel strength when the surface finish is adhered to the mortar surface, but has a low planar tensile strength and is further an aqueous adhesive. Therefore, there is a problem that water resistance is low.

  Further, the surface finishing material of the outer wall expands under a high temperature environment such as summer, but shrinks under a low temperature environment such as winter.

  However, since the adhesive layer of the conventional adhesive composition has low rubber elasticity and adhesive strength, the adhesive layer cannot follow the expansion and contraction of the outer wall surface finish material, and the surface finish of the adhesive layer and the outer wall. In some cases, the material peeled off. Therefore, it is desired that the adhesive composition can form an adhesive layer that is excellent in both planar tensile strength and peel strength.

  Furthermore, moisture such as moisture in the air or rainwater penetrates the surface finishing material or adhesive layer of the outer wall and comes into contact with the concrete. Since concrete contains calcium hydroxide and the like, moisture is alkaline when it comes into contact with concrete. The adhesive layer of the conventional adhesive composition also has a problem that the adhesiveness decreases with time when it comes into contact with alkaline moisture. Therefore, it is desired for the adhesive composition to exhibit good planar tensile strength and peel strength even when moisture enters the adhesive layer and exhibits alkalinity.

  Accordingly, the present invention provides an adhesive composition that has excellent rubber elasticity and adhesive strength, and can form an adhesive layer that exhibits excellent planar tensile strength and peel strength even when contacted with alkaline moisture. Offer things.

The adhesive composition of the present invention comprises 100 parts by mass of a polyalkylene oxide (A) having a hydrolyzable silyl group,
10 to 100 parts by mass of fatty acid-treated calcium oxide (B),
1 to 10 parts by mass of an aminosilane coupling agent (C),
Including a silanol condensation catalyst (D),
The mass ratio of the fatty acid-treated calcium oxide (B) and the aminosilane coupling agent (C) [mass of the fatty acid-treated calcium oxide (B) / mass of the aminosilane coupling agent (C)] is 2 to 40. .

  Since the present invention has the configuration as described above, the adhesive layer has excellent rubber elasticity and adhesive strength, and exhibits excellent planar tensile strength and peel strength even when in contact with alkaline moisture. Can be formed.

  Since the adhesive layer formed from the adhesive composition of the present invention is excellent in rubber elasticity and adhesive strength, even when the surface finish material expands or contracts, the expansion and contraction are smooth. The surface finishing material and the adhesive layer can be effectively prevented from peeling off, and the surface finishing material can be stably bonded and integrated over a long period of time.

[Polyalkylene oxide (A) having hydrolyzable silyl group]
The adhesive composition of the present invention contains a polyalkylene oxide (A) having a hydrolyzable silyl group.

  The hydrolyzable silyl group is a group in which 1 to 3 hydrolyzable groups are bonded to a silicon atom. The hydrolyzable group of the hydrolyzable silyl group is not particularly limited, and examples thereof include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, and a mercapto group. Group, alkenyloxy group and the like. Of these, an alkoxy group is preferable. Alkoxy groups are less likely to produce harmful byproducts after the reaction.

  Among these, as the hydrolyzable silyl group, an alkoxysilyl group is preferable because the hydrolysis reaction is gentle. Examples of alkoxysilyl groups include trialkoxysilyl groups such as trimethoxysilyl group, triethoxysilyl group, triisopropoxysilyl group, and triphenoxysilyl group; dialkoxysilyl groups such as methyldimethoxylyl group and methyldiethoxysilyl group Groups; and monoalkoxysilyl groups such as a dimethylmethoxysilyl group and a dimethylethoxysilyl group. Of these, a dialkoxysilyl group is more preferable, and a dimethoxysilyl group is particularly preferable.

  The average number of hydrolyzable silyl groups per molecule of the polyalkylene oxide (A) is preferably 1 to 2. The polyalkylene oxide preferably has hydrolyzable silyl groups at both ends of the polymer main chain. When the average number of hydrolyzable silyl groups is 1 or more, the adhesive layer formed from the adhesive composition has excellent planar tensile strength even when in contact with alkaline water. When the average number of hydrolyzable silyl groups is 2 or less, the adhesive layer formed from the adhesive composition has excellent peel strength even when in contact with alkaline water.

The average number of hydrolyzable silyl groups per molecule of polyalkylene oxide (A) is determined by the concentration of hydrolyzable silyl groups in polyalkylene oxide (A) determined by ¹ H-NMR and the GPC method. It can be calculated based on the required number average molecular weight of the polyalkylene oxide (A).

  Examples of the main chain skeleton of the polyalkylene oxide (A) include polyethylene oxide, polypropylene oxide, polybutylene oxide, polyethylene oxide-polypropylene oxide copolymer, and polypropylene oxide-polybutylene oxide copolymer. Of these, polypropylene oxide is preferable. According to the adhesive composition containing polypropylene oxide, an adhesive layer excellent in rubber elasticity can be formed.

  The number average molecular weight of the polyalkylene oxide (A) is preferably 20000 to 50000, and more preferably 20000 to 30000. When the number average molecular weight is 20000 or more, the adhesive layer formed from the adhesive composition has excellent peel strength even when it comes into contact with alkaline water. When the number average molecular weight is 50000 or less, the adhesive layer formed from the adhesive composition has excellent planar tensile strength even when it comes into contact with alkaline water.

  In the present invention, the number average molecular weight of the polyalkylene oxide (A) is a value measured by polystyrene conversion by GPC (gel permeation chromatography) method. Specifically, 6 to 7 mg of polyalkylene oxide is collected, and the collected polyalkylene oxide is supplied to a test tube. Prepare an orthodichlorobenzene (o-DCB) solution containing 0.05% by weight of dibutylhydroxytoluene (BHT) and add this solution to a test tube to dilute the polyalkylene oxide to a concentration of 1 mg / mL. To prepare a diluted solution. The dilution liquid is shaken for 1 hour at a rotation speed of 25 rpm at 145 ° C. using a dissolution filter, and the polyalkylene oxide is dissolved in the solution to obtain a measurement sample. Using this measurement sample, the number average molecular weight of the polyalkylene oxide can be measured by the GPC method.

The number average molecular weight of the polyalkylene oxide can be measured, for example, with the following measuring apparatus and measurement conditions.
Product name “HLC-8121GPC / HT” manufactured by TOSOH
Measurement conditions Column: TSKgelGMHHR-H (20) HT x 3
TSK guard column-HHR (30) HT x 1
Mobile phase: o-DCB 1.0 mL / min
Sample concentration: 1 mg / mL
Detector: Bryce refractometer
Standard substance: polystyrene (Molecular weight: 500-8420000, manufactured by TOSOH)
Elution conditions: 145 ° C
SEC temperature: 145 ° C

  A commercially available product can be used as the polyalkylene oxide (A) having a hydrolyzable silyl group. For example, products marketed by Kaneka under the trade names “MS Polymer S-203” and “MS Polymer S-303”, and from Asahi Glass under the trade names “Exstar ESS-2410” and “Excestar ESS-2420” Can be used.

[Fatty acid-treated calcium oxide (B)]
The adhesive composition of the present invention contains fatty acid-treated calcium oxide. According to the adhesive composition containing the fatty acid-treated calcium oxide, it is possible to form an adhesive layer in which moisture such as moisture in the air or rainwater hardly penetrates. Thereby, it can reduce that a water | moisture content contacts concrete and exhibits alkalinity. Therefore, the contact between the adhesive layer and the alkaline moisture can be suppressed, and the adhesiveness excellent in the adhesive layer can be maintained over a long period of time. In particular, even when placed over a long period of time in a harsh environment exposed to rainwater, such as outdoors, the surface finish and the adhesive layer can be kept in an integrated state, The excellent aesthetics of the surface finish can be maintained.

  Fatty acid-treated calcium oxide is calcium oxide whose surface is treated with a fatty acid. Examples of the fatty acid include saturated fatty acids such as decanoic acid, dodecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, and icosanoic acid; hexadecenoic acid, octadecenoic acid, octadecadienoic acid, octadecatrienoic acid And unsaturated fatty acids such as icosanoic acid, icosadienoic acid, icosatrienoic acid, icosatetratrienoic acid, and tetradocosanoic acid. Of these, saturated fatty acids are preferable and octadecanoic acid is preferable from the viewpoint of compatibility with the polymer. These fatty acids may be used alone or in combination of two or more.

  The average particle diameter of the fatty acid-treated calcium oxide is preferably 0.05 to 100 μm, and more preferably 1 to 50 μm. Fatty acid-treated calcium oxide having an average particle size within the above range can be highly dispersed in the adhesive composition, thereby reducing moisture penetration into the adhesive layer and adhesive. The adhesive layer formed from the composition has even more excellent planar tensile strength and peel strength even when in contact with alkaline moisture.

  The average particle size of the fatty acid-treated calcium oxide can be measured using a laser diffraction / scattering particle size analyzer. For example, after adding fatty acid-treated calcium oxide to methanol so that its concentration becomes 10% by mass, a suspension is obtained by irradiating with ultrasonic waves at an output of 1 kW for 10 minutes using an ultrasonic homogenizer. The volume particle size distribution of the fatty acid-treated calcium oxide is measured with a laser diffraction / scattering particle size analyzer (for example, trade name “SACD-2100” manufactured by Shimadzu Corporation) for the liquid, and the cumulative 50% value of the volume particle size distribution is calculated. It can be calculated as the average particle size of the fatty acid-treated calcium oxide.

  Fatty acid-treated calcium oxide is commercially available, for example, from Omi Chemical Industry under the trade names “CML # 31” and “CML # 35”.

  The content of the fatty acid-treated calcium oxide in the adhesive composition is 10 to 100 parts by mass with respect to 100 parts by mass of the polyalkylene oxide having a hydrolyzable silyl group, preferably 20 to 100 parts by mass, and 40 to 100. Part by mass is more preferable. When the content of the fatty acid-treated calcium oxide is 10 parts by mass or more, the penetration of moisture into the adhesive layer can be effectively suppressed. When the content of the fatty acid-treated calcium oxide is 100 parts by mass or less, the adhesive layer formed from the adhesive composition has further excellent rubber elasticity and peel strength, and is in contact with alkaline moisture. Furthermore, excellent peel strength is exhibited.

[Aminosilane coupling agent (C)]
The adhesive composition of the present invention contains an aminosilane coupling agent (C). The aminosilane coupling agent means a compound containing a silicon atom having an alkoxy group bonded in one molecule and a functional group having an amino group. According to the aminosilane coupling agent, the adhesiveness of the adhesive composition can be further improved by using it together with the epoxysilane coupling agent.

  Specific examples of the aminosilane coupling agent include 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, and N- (2-aminoethyl) -3-aminopropylmethyl. Dimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, N, N′-bis- [3- (trimethoxy Silyl) propyl] ethylenediamine, N, N′-bis- [3- (triethoxysilyl) propyl] ethylenediamine, N, N′-bis- [3- (methyldimethoxysilyl) propyl] ethylenediamine, N, N′-bis -[3- (trimethoxysilyl) propyl] hexamethylenediamine, N, N - bis - such as [3- (triethoxysilyl) propyl] hexamethylenediamine can be mentioned, N- (2- aminoethyl) -3-aminopropyltrimethoxysilane is preferred.

  Content of the aminosilane coupling agent in an adhesive composition is 1-10 mass parts with respect to 100 mass parts of polyalkylene oxide (A) which has a hydrolyzable silyl group, and 2-8 mass parts is preferable, 2-6 mass parts is more preferable. When the content of the aminosilane coupling agent is 1 part by mass or more, the adhesive layer formed from the adhesive composition has excellent planar tensile strength and peel strength even when in contact with alkaline moisture. . When the content of the aminosilane coupling agent is 10 parts by mass or less, the adhesive layer formed from the adhesive composition has excellent peel strength even when it comes into contact with alkaline moisture.

  In the adhesive composition, the mass ratio of the fatty acid-treated calcium oxide (B) and the aminosilane coupling agent (C) [the mass of the fatty acid-treated calcium oxide (B) / the mass of the aminosilane coupling agent (C)] is 2 to 2. 40, preferably 2-20. When the mass ratio of the fatty acid-treated calcium oxide (B) and the aminosilane coupling agent (C) is 2 or more, the adhesive layer formed from the adhesive composition may further be in contact with alkaline water. Excellent peel strength. When the mass ratio of the fatty acid-treated calcium oxide (B) and the aminosilane coupling agent (C) is 40 or less, the adhesive strength of the adhesive layer formed from the adhesive composition is improved.

[Silanol condensation catalyst (D)]
The adhesive composition of the present invention contains a silanol condensation catalyst (D). The silanol condensation catalyst (D) is a catalyst for promoting a dehydration condensation reaction between silanol groups formed by hydrolyzing the hydrolyzable silyl group of the polyalkylene oxide and the alkoxy group of the aminosilane coupling agent. is there. The silanol group means a hydroxy group (≡Si—OH) bonded directly to a silicon atom.

  Examples of the silanol condensation catalyst (D) include 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane, dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate bis ( Dibutyltin lauric acid) oxide, dibutyltin bisacetylacetonate, dibutyltin bis (monoester malate), tin octylate, dibutyltin octoate, dioctylate oxide, tin compound having alkoxysilyl group, tetra-n-butoxytitanate , Tetraisopropoxy titanate, dibutylamine-2-ethylhexoate, and the like. Among these, 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane is preferable in order to maintain stability during storage of the adhesive. A silanol condensation catalyst may be used independently and 2 or more types may be used together.

  As for content of the silanol condensation catalyst (D) in adhesive composition, 0.1-3 mass parts is preferable with respect to 100 mass parts of polyalkylene oxide (A) which has a hydrolysable silyl group, and 1-3 mass. Part is more preferred. When the content of the silanol condensation catalyst is 0.1 parts by mass or more, the curability of the adhesive composition is improved. The storage stability of an adhesive composition improves that content of a silanol condensation catalyst is 3 mass parts or less.

[Epoxysilane coupling agent (E)]
The adhesive composition of the present invention preferably further contains an epoxy silane coupling agent from the viewpoint of enhancing the adhesion to an inorganic substrate such as concrete. The epoxy silane coupling agent means a compound containing a silicon atom having an alkoxy group bonded in one molecule and a functional group having an epoxy group. According to the epoxy silane coupling agent, the adhesion to inorganic materials such as mortar can be further improved.

  Specific examples of the epoxy silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylethyldisilane. Examples thereof include ethoxysilane and 2- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, and 3-glycidoxypropyltrimethoxysilane is preferred. An epoxy silane coupling agent may be used individually by 1 type, or 2 or more types may be used together.

  In the adhesive composition, the ratio of the number of moles of amino groups in the aminosilane coupling agent (C) to the number of moles of epoxy groups in the epoxysilane coupling agent (E) [in the aminosilane coupling agent (C) The number of moles of amino group / number of moles of epoxy group in the epoxy silane coupling agent (E)] is preferably 3.0 or more, more preferably 4.0 or more, and particularly preferably 5.0 or more. Ratio of moles of amino groups in aminosilane coupling agent (C) and moles of epoxy groups in epoxysilane coupling agent (E) [number of moles of amino groups in aminosilane coupling agent (C) / epoxy The number of moles of epoxy group in the silane coupling agent (E) is preferably 10.0 or less, more preferably 9.0 or less, and particularly preferably 8.0 or less. Ratio of moles of amino groups in aminosilane coupling agent (C) and moles of epoxy groups in epoxysilane coupling agent (E) [number of moles of amino groups in aminosilane coupling agent (C) / epoxy When the number of moles of epoxy groups in the silane coupling agent (E) is 3.0 or more, the storage stability of the adhesive composition is improved. Ratio of moles of amino groups in aminosilane coupling agent (C) and moles of epoxy groups in epoxysilane coupling agent (E) [number of moles of amino groups in aminosilane coupling agent (C) / epoxy When the number of moles of epoxy groups in the silane coupling agent (E) is 10.0 or less, the adhesion between the adhesive layer formed from the adhesive composition and the organic surface finish is improved. The adhesive layer formed from the adhesive composition has excellent peel strength, and particularly maintains excellent flat tensile strength and peel strength even in contact with alkaline moisture.

[Fibrous filler]
The adhesive composition of the present invention preferably contains a fibrous filler. When the adhesive composition contains a fibrous filler, the adhesive layer formed from the adhesive composition has excellent planar tensile strength, and particularly excellent planarity even when in contact with alkaline moisture. Maintain tensile strength.

The fibrous filler is not particularly limited. For example, glass fiber, wollastonite, potassium titanate, basic magnesium sulfate (MgSO ₄ .5Mg (OH) ₂ .3H ₂ O), sepiolite, zonotlite, aluminum borate Basic magnesium sulfate (MgSO ₄ .5Mg (OH) ₂ .3H ₂ O) is preferable. Basic magnesium sulfate is commercially available from Ube Materials Co., Ltd. under the trade name “MOS • HIGE”.

  The aspect ratio of the fibrous filler is preferably 5 or more. When the aspect ratio of the fibrous filler is 5 or more, the adhesive layer formed from the adhesive composition has excellent flat tensile strength, and particularly excellent flat tensile strength even when in contact with alkaline moisture. To maintain. The aspect ratio of the fibrous filler is a value obtained by dividing the length of the fiber by the diameter of the fiber. The length of the fibrous filler refers to the dimension of the portion where the fibrous filler is the longest. The diameter of the fibrous filler refers to the diameter of a perfect circle having the smallest diameter that can surround the fibrous filler in a direction orthogonal to the longest direction of the fibrous filler.

  3-20 mass parts is preferable with respect to 100 mass parts of polyalkylene oxide (A) which has a hydrolysable silyl group, and, as for content of the fibrous filler in an adhesive composition, 5-10 mass parts is more preferable. When the content of the fibrous filler is within the above range, the adhesive layer formed from the adhesive composition has excellent flat tensile strength, and particularly excellent flat tensile even when in contact with alkaline moisture. Maintain strength.

[Other additives]
The adhesive composition of the present invention may further contain other additives as required. Examples of other additives include dehydrating agents, epoxy silane coupling agents, antioxidants, fillers, plasticizers, sagging inhibitors, ultraviolet absorbers, pigments, solvents, and fragrances.

[Dehydrating agent]
The adhesive composition of the present invention preferably further contains a dehydrating agent. According to the dehydrating agent, when the adhesive composition is stored, the adhesive composition can be prevented from being cured by moisture such as moisture in the air.

  Examples of the dehydrating agent include silane compounds such as vinyltrimethoxysilane, dimethyldimethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, phenyltrimethoxysilane, and diphenyldimethoxysilane; Examples thereof include ester compounds such as methyl acid, ethyl orthoformate, methyl orthoacetate, and ethyl orthoacetate, and vinyltrimethoxysilane is preferred. These dehydrating agents may be used alone or in combination of two or more.

  The content of the dehydrating agent in the adhesive composition is preferably 0.5 to 20 parts by mass and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the polyalkylene oxide (A) having a hydrolyzable silyl group. 1 to 5 parts by mass is preferable.

〔Antioxidant〕
The adhesive composition of the present invention preferably further contains an antioxidant. Examples of the antioxidant include hindered phenolic antioxidants, monophenolic antioxidants, bisphenolic antioxidants, and polyphenolic antioxidants. Of these, hindered phenol antioxidants are preferred. Specific examples of hindered phenol antioxidants include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-). tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide)] and the like. It is done. An antioxidant may be used individually by 1 type, or 2 or more types may be used together.

  0.1-20 mass parts is preferable with respect to 100 mass parts of polyalkylene oxide (A) which has a hydrolyzable silyl group, and, as for content of antioxidant in adhesive composition, 0.3-10 mass Part is more preferred.

[Filler]
The adhesive composition of the present invention preferably further contains a filler. Examples of the filler include calcium carbonate, magnesium carbonate, hydrous silicic acid, anhydrous silicic acid, calcium silicate, silica, titanium dioxide, clay, talc, carbon black, glass balloon and the like, preferably calcium carbonate, colloidal Calcium carbonate is more preferred. A filler may be used individually by 1 type and 2 or more types may be used together.

[Plasticizer]
The adhesive composition of the present invention preferably contains a plasticizer. According to the adhesive composition containing the plasticizer, an adhesive layer capable of maintaining excellent rubber elasticity over a long period of time can be formed.

  Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, di-hexyl phthalate, bis (2-ethylhexyl) phthalate, di-normal octyl phthalate, diisononyl phthalate, and phthalic acid Phthalic acid esters such as dinonyl, diisodecyl phthalate, diisoundecyl phthalate, and bisbutylbenzyl phthalate; polyalkylene glycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, and tetrapropylene glycol Can be mentioned. Of these, polyalkylene glycol is preferable, and polypropylene glycol is more preferable.

  1000-10000 are preferable and, as for the number average molecular weight of polyalkylene glycol, 1000-5000 are more preferable. When the number average molecular weight of the polyalkylene glycol is within the above range, the adhesive composition can form an adhesive layer that can maintain excellent rubber elasticity over a long period of time.

  In the present invention, the number average molecular weight of the polyalkylene glycol is a value measured by polystyrene conversion by GPC (gel permeation chromatography) method. Specific measurement methods and measurement conditions are the same as those of the polyalkylene oxide described above.

  The content of the plasticizer in the adhesive composition is preferably 20 to 120 parts by weight, more preferably 30 to 100 parts by weight, based on 100 parts by weight of the polyalkylene oxide (A) having a hydrolyzable silyl group. -100 mass parts is especially preferable. When the content of the plasticizer is 20 parts by mass or more, the adhesive layer formed from the adhesive composition has excellent peel strength. When the content of the plasticizer is 120 parts by mass or less, the adhesive layer formed from the adhesive composition maintains excellent planar tensile strength even when it comes into contact with alkaline moisture.

[Anti-sagging agent]
The adhesive composition of the present invention may contain an anti-sagging agent. Examples of the sagging inhibitor include hydrogenated castor oil, fatty acid bisamide, and fumed silica.

[Ultraviolet absorber]
The adhesive composition of the present invention may contain an ultraviolet absorber. Examples of the ultraviolet absorber include hindered amine light stabilizers such as bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, benzotriazole ultraviolet absorbers, and the like.

  The adhesive composition preferably comprises a polyalkylene oxide (A), a fatty acid-treated calcium oxide (B), an aminosilane coupling agent (C) and a silanol condensation catalyst (D), and optionally an additive in a stirrer. It can manufacture by mixing until it becomes uniform, reducing pressure.

  The adhesive composition can form an adhesive layer that is excellent in adhesive strength and rubber elasticity. Furthermore, the cured composition can form an adhesive layer with reduced moisture penetration by using fatty acid-treated calcium oxide. Therefore, it is possible to reduce the generation of alkaline moisture due to contact between concrete and moisture, and it is also possible to reduce the decrease in planar tensile strength and peel strength of the adhesive layer due to contact with alkaline moisture.

  Such an adhesive composition is suitably used for bonding and integrating a surface finish on a concrete surface. Specifically, after the adhesive composition is applied to the concrete surface, a surface finishing material having a thickness of 1 to 5 mm is laminated on the applied adhesive composition, and these are left to be cured for adhesion. An adhesive layer is formed by curing the agent composition. As a result, a building structure in which the surface finish is bonded and integrated on the concrete surface through the adhesive layer obtained by curing the adhesive composition is obtained.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

(Examples 1-15 and Comparative Examples 1-4)
The components shown below were blended in the blending amounts shown in Tables 1 and 2, and kneaded for 60 minutes in a vacuum atmosphere using a planetary mixer to obtain an adhesive composition. In Table 1, the polyalkylene oxide (A) having a hydrolyzable silyl group was simply expressed as “polyalkylene oxide (A)”.

[Polyalkylene oxide (A) having hydrolyzable silyl group]
Polyalkylene oxide (A) having hydrolyzable silyl groups (polyalkylene oxide having a main chain made of polypropylene oxide and having a dimethoxysilyl group at the end of the main chain, the average number of methoxysilyl groups per molecule: 1. 4; number average molecular weight: 20000, trade name “MS Polymer S-203” manufactured by Kaneka Corporation

[Fatty acid-treated calcium oxide (B)]
Fatty acid-treated calcium oxide (calcium oxide whose surface is treated with octadecanoic acid, average particle size: 10 μm, trade name “CML # 31” manufactured by Omi Chemical Co., Ltd.)

[Aminosilane coupling agent (C)]
Aminosilane coupling agent (N- (2-aminoethyl) -3-aminopropyltrimethoxysilane)

[Silanol condensation catalyst (D)]
Silanol condensation catalyst (1, 1, 3, 3-tetrabutyl-1, 3-dilauryloxycarbonyl-distannoxane, product name “Neostan U-130” manufactured by Nitto Kasei Co., Ltd.)

[Epoxysilane coupling agent (E)]
・ Epoxysilane coupling agent (3-glycidoxypropyltrimethoxysilane)

[Plasticizer]
Plasticizer (polypropylene glycol, number average molecular weight: 3000, trade name “P-3000” manufactured by Asahi Denka Co., Ltd.)

[Dehydrating agent]
・ Dehydrating agent (Vinyltrimethoxysilane, trade name “NUC Silicone A171” manufactured by Nihon Unica)

〔Antioxidant〕
Antioxidant (pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]

〔filler〕
・ Filler (Colloidal calcium carbonate, trade name “CCR” manufactured by Shiroishi Kogyo Co., Ltd.)

[Fibrous filler]
・ Basic magnesium sulfate (trade name “MOS ・ HIGE” manufactured by Ube Materials)

  About the obtained adhesive composition, planar tensile strength and peel strength, and elongation at break were measured in the following manner, and the results are shown in Tables 1 and 2.

(Plane tensile strength and peel strength)
In accordance with JIS A5557, a standard mortar test piece and a soft polyvinyl chloride sheet are obtained by superposing a standard mortar test piece and a soft polyvinyl chloride sheet having a thickness of 2 mm on the adhesive composition, and curing the standard. A specimen was prepared by bonding and integration. Based on the obtained specimen, the plane tensile strength and 90 ° peel strength were measured. The measurement results are listed in the “standard curing” column.

  Further, the test specimen prepared in the above manner was subjected to an alkaline hot water immersion treatment, and then the plane tensile strength and 90 ° peel peel strength were measured based on the test specimen. The measurement results are shown in the column of “Alkaline hot water immersion treatment”.

(Elongation at break)
The elongation at break of the adhesive layer obtained by curing the obtained adhesive composition was measured according to JIS A 5557.

Claims (4)

100 parts by mass of polyalkylene oxide (A) having a hydrolyzable silyl group,
10 to 100 parts by mass of fatty acid-treated calcium oxide (B),
1 to 10 parts by mass of an aminosilane coupling agent (C),
A silanol condensation catalyst (D),
The mass ratio of the fatty acid-treated calcium oxide (B) and the aminosilane coupling agent (C) [mass of fatty acid-treated calcium oxide (B) / mass of aminosilane coupling agent (C)] is 2 to 40. An adhesive composition.   The polyalkylene oxide (A) having a hydrolyzable silyl group contains 30 to 100 parts by mass of polypropylene glycol having a number average molecular weight of 1000 to 5000 with respect to 100 parts by mass. Adhesive composition.   Further containing an epoxy silane coupling agent (E), the ratio of the number of moles of amino groups in the amino silane coupling agent (C) to the number of moles of epoxy groups in the epoxy silane coupling agent (E) [amino silane cup The number of moles of amino groups in the ring agent (C) / the number of moles of epoxy groups in the epoxy silane coupling agent (E)] is 3.0 or more. Adhesive composition.   4. The composition according to claim 1, further comprising 3 to 20 parts by mass of a fibrous filler having an aspect ratio of 5 or more with respect to 100 parts by mass of the polyalkylene oxide (A) having a hydrolyzable silyl group. The adhesive composition according to any one of the above.