JP6598499B2 - Adhesive composition - Google Patents

Description

  The present invention relates to an adhesive composition.

  Conventionally, an adhesive composition containing a polyoxyalkylene polymer having a crosslinkable silyl group has been suitably used for bonding various organic materials because its cured product is flexible and rich in elongation.

  On the other hand, the cured product of the adhesive composition containing a polyoxyalkylene polymer having a crosslinkable silyl group is excellent in elongation, but is poor in alkali resistance, so it is applied to an inorganic material such as mortar showing high alkalinity. In this case, it is necessary to pre-treat the adhesion site with a primer or the like, and there is a problem that the adhesive strength decreases with time.

  In order to solve the above problems, Patent Document 1 discloses (a) an oxyalkylene polymer containing a reactive silicon group, (b) a reaction product of dibutyltin salt and normal ethyl silicate, (c) epoxy. It is a moisture curable resin composition containing at least a resin and a ketimine compound as a latent curing agent for (d) and (c). In addition, (a) an oxyalkylene polymer containing a reactive silicon group, (b) a curing catalyst of (a), (c) an epoxy resin, and (d) a ketimine compound serving as a latent curing agent of (c) A moisture-curing resin composition containing it has been proposed.

JP2011-12144A

  However, although the moisture curable resin composition has improved alkali resistance, it has low adhesion to organic materials such as polyvinyl chloride and polyethylene terephthalate, resulting in interfacial fracture and a significant decrease in adhesive strength over time. Have the problem of Furthermore, the cured product of the moisture curable resin composition also has a problem of low elongation.

  The present invention provides an adhesive composition that forms a cured product having excellent elongation and alkali resistance, and also has excellent adhesion to organic materials.

The adhesive composition of the present invention has 100 parts by mass of a polyoxyalkylene polymer having 0.5 to 2 crosslinkable silyl groups on an average number per molecule,
5 to 100 parts by mass of magnesium oxide,
0.5 to 5 parts by mass of an aminosilane coupling agent,
It contains 0.1 to 3 parts by mass of a silanol condensation catalyst.

  The adhesive composition is characterized by further containing 10 to 100 parts by mass of polypropylene glycol with respect to 100 parts by mass of the polyoxyalkylene polymer.

  The adhesive composition of the present invention is cured by moisture in the air or moisture contained in the adherend, forms a cured product having excellent elongation and alkali resistance, and has excellent adhesiveness. Furthermore, since the adhesive composition of the present invention has excellent adhesion to organic materials, not only adhesion between inorganic materials such as mortar but also adhesion between inorganic materials and organic materials. Also, it can be suitably used.

  The adhesive composition of the present invention comprises a polyoxyalkylene polymer having 0.5 to 2 crosslinkable silyl groups on an average per molecule, magnesium oxide, an aminosilane coupling agent, and silanol. It contains a condensation catalyst.

[Polyoxyalkylene polymer]
In the polyoxyalkylene polymer having a crosslinkable silyl group, the main chain has a general formula:-(R-O) _n- (wherein R represents an alkylene group having 1 to 14 carbon atoms, n is A polymer containing a repeating unit represented by the number of repeating units and a positive integer is preferred. The main chain skeleton of the polyoxyalkylene polymer may be composed of only one type of repeating unit, or may be composed of two or more types of repeating units.

  The main chain skeleton of the polyoxyalkylene polymer includes polyoxyethylene, polyoxypropylene, polyoxybutylene, polyoxytetramethylene, polyoxyethylene-polyoxypropylene copolymer, and polyoxypropylene-polyoxybutylene copolymer. Polymers etc. are mentioned, and since the hardened | cured material of adhesive composition is excellent in elongation property, it is preferable that polyoxypropylene is included.

  The polyoxyalkylene polymer has 0.5 to 2 crosslinkable silyl groups on an average number per molecule. As the crosslinkable silyl group, for example, a condensation reaction may be performed by using a catalyst or the like, if necessary, in the presence of moisture or a crosslinker such as a silicon-containing group or silanol group having a hydrolyzable group bonded to a silicon atom. Refers to a group that yields

  Examples of the hydrolyzable group bonded to the silicon atom include hydrogen, halogen atom, alkoxy group, acyl oxide group, ketoximate group, amino group, amide group, acid amide group, aminooxy group, mercapto group, alkenyl oxide group, etc. And alkoxy groups are preferred because they do not produce harmful by-products after the reaction.

  Examples of the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butoxy group, a tert-butoxy group, a phenoxy group, and a benzyloxy group, and a methoxy group and an ethoxy group are preferable.

  Examples of the crosslinkable silyl group include trialkoxysilyl groups such as trimethoxysilyl group, triethoxysilyl group, triisopropoxysilyl group and triphenoxysilyl group; dialkoxy such as methyldimethoxysilyl group and methyldiethoxysilyl group Silyl group; monoalkoxysilyl groups such as methoxysilyl group, dimethylmethoxysilyl group, dimethylethoxysilyl group and the like can be mentioned. The polyoxyalkylene polymer may contain one or more crosslinkable silyl groups.

  The number average number of crosslinkable silyl groups per molecule in the polyoxyalkylene polymer is 0.5 to 2, preferably 0.5 to 1.5, and 1.0 to 1.5. More preferred. When the average number of crosslinkable silyl groups is 0.5 or more, the extensibility of a cured product obtained by curing the adhesive composition is excellent. When the average number of crosslinkable silyl groups is 2 or less, the extensibility of a cured product obtained by curing the adhesive composition is excellent.

The number average number of hydrolyzable silyl groups in one molecule in the polyoxyalkylene polymer depends on the ratio of the peak area derived from the hydrolyzable silyl group in the polyoxyalkylene polymer determined by ¹ H-NMR. Can be calculated.

  The polyoxyalkylene polymer may further have a urethane bond in addition to the crosslinkable silyl group. The urethane bond can impart polarity to the polyoxyalkylene polymer, thereby imparting excellent extensibility to a cured product obtained by curing the adhesive composition.

  The polyoxyalkylene polymer may have a crosslinkable silyl group via a urethane bond at both ends of the polyoxyalkylene chain, or it may be crosslinkable without a urethane bond at both ends of the polyoxyalkylene chain. It may have a silyl group.

  The polyoxyalkylene polymer having a crosslinkable silyl group via a urethane bond at both ends of the polyoxyalkylene chain includes, for example, a prepolymer having hydroxyl groups at both ends of the polyoxyalkylene chain, a crosslinkable silyl group, and It is obtained by reacting with a compound having an isocyanate group.

  Examples of the prepolymer having hydroxyl groups at both ends of the polyoxyalkylene chain include polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, polyoxytetramethylene glycol, polyoxyethylene-polyoxypropylene glycol, and polyoxyethylene Examples include propylene-polyoxybutylene glycol.

  Examples of the compound having a crosslinkable silyl group and an isocyanate group include 1-isocyanate methyltrimethoxysilane, 2-isocyanateethyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, 3-isocyanatebutyltrimethoxysilane, 3-isocyanatepentyltril. Examples include methoxysilane and 1-isocyanatopropyltrimethoxysilane.

  In order to synthesize a polyoxyalkylene polymer having a crosslinkable silyl group via a urethane bond at both ends of the polyoxyalkylene chain, a prepolymer having a hydroxy group at both ends of the polyoxyalkylene chain and a crosslinkable silyl Mixing a compound having a group and an isocyanate group to obtain a mixture, and stirring the mixture to react the hydroxy group of the prepolymer with the isocyanate group of the compound to form a urethane bond. it can. Moreover, reaction can be accelerated | stimulated by stirring the said mixture, heating.

  A polyoxyalkylene polymer having a crosslinkable silyl group without a urethane bond at both ends of the polyoxyalkylene chain is, for example, an oxyalkylene polymer having a functional group such as a hydroxyl group at the terminal. It is produced by reacting an organic compound having an active group and an unsaturated group that are reactive to a functional group, and then hydrolylating the resulting reaction product with hydrosilane having a hydrolyzable group. be able to.

  The number average molecular weight of the polyoxyalkylene polymer is preferably 3000 to 50000, more preferably 10,000 to 25000, and particularly preferably 10,000 to 20000. When the number average molecular weight of the polyoxyalkylene polymer is 50000 or less, the extensibility of a cured product obtained by curing the adhesive composition is excellent. When the number average molecular weight of the polyoxyalkylene polymer is 3000 or more, the elongation of the cured product of the adhesive composition is preferably improved.

  In the present invention, the number average molecular weight of the polyoxyalkylene polymer is a value in terms of polystyrene measured by a GPC (gel permeation chromatography) method. Specifically, 6 to 7 mg of a polyoxyalkylene polymer is sampled, and after the collected polyoxyalkylene polymer is supplied to a test tube, 0.05% by mass of BHT (dibutylhydroxytoluene) is added to the test tube. An o-DCB (orthodichlorobenzene) solution containing is added to dilute the polyoxyalkylene polymer 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 polyoxyalkylene polymer is dissolved in an o-DCB solution containing BHT to obtain a measurement sample. . Using this measurement sample, the number average molecular weight of the polyoxyalkylene polymer can be measured by the GPC method.

The number average molecular weight in the polyoxyalkylene polymer 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
TSKguardcolumn-HHR (30) HT x 1
Mobile phase: o-DCB 1.0 mL / min
Sample concentration: 1 mg / mL
Detector: Bryce refractometer
Reference material: Polystyrene (Molecular weight: 500-8420000, manufactured by TOSOH)
Elution conditions: 145 ° C
SEC temperature: 145 ° C

  Examples of the polyoxyalkylene polymer include trade names “MS Polymer S-203”, “MS Polymer S-303”, “Syryl Polymer SAT-200”, and “Syryl Polymer SAT-350” manufactured by Kaneka Corporation. ”And“ Syryl Polymer SAT-400 ”, commercially available products such as“ EXCESTERS ESS-3620 ”,“ EXCester ESS-2420 ”,“ Excester ESS2410 ”and“ Excester ESS3430 ”manufactured by Asahi Glass Co., Ltd. are used. be able to.

[Magnesium oxide]
The adhesive composition contains magnesium oxide. Since the adhesive composition contains a polyoxyalkylene polymer and magnesium oxide, the cured product of the adhesive composition has excellent alkali resistance, and the adhesive composition is an organic material. It has excellent adhesiveness. Examples of organic materials include polyvinyl chloride materials and polyethylene terephthalate materials.

  The average particle diameter of magnesium oxide is preferably 10 to 150 μm, more preferably 20 to 75 μm, and particularly preferably 30 to 50 μm. When the average particle diameter of magnesium oxide is 10 μm or more, an increase in the viscosity of the adhesive composition is suppressed, and the handleability is improved. When the average particle diameter of magnesium oxide is 150 μm or less, a cured product obtained by curing the adhesive composition becomes tough.

  The average particle diameter of magnesium oxide is a value measured using a laser diffraction / scattering particle size analyzer. For example, after putting magnesium oxide into methanol so that the concentration thereof is 10% by mass, an ultrasonic homogenizer is used to irradiate ultrasonic waves at an output of 1 kW for 10 minutes to obtain a suspension. This suspension was measured for volume particle size distribution of magnesium oxide by a laser diffraction / scattering particle size analyzer (for example, trade name “SACD-2100” manufactured by Shimadzu Corporation), and a cumulative 50% value of the volume particle size distribution. Is the average particle size of magnesium oxide.

  The content of magnesium oxide in the adhesive composition is 5 to 100 parts by mass, preferably 10 to 80 parts by mass, and more preferably 20 to 60 parts by mass with respect to 100 parts by mass of the polyoxyalkylene polymer. When the content of magnesium oxide is 5 parts by mass or more, a cured product obtained by curing the adhesive composition has excellent alkali resistance. When the content of magnesium oxide is 100 parts by mass or less, a cured product obtained by curing the adhesive composition has excellent flexibility.

[Aminosilane coupling agent]
The adhesive composition contains an aminosilane coupling agent. The aminosilane coupling agent means a compound containing a silicon atom having an alkoxy group bonded in one molecule and a functional group containing a nitrogen atom. By using an aminosilane coupling agent, the cured product of the adhesive composition has excellent elongation and alkali resistance.

  Specific examples of aminosilane coupling agents include 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, and N- (2-aminoethyl) -3-aminopropyltrimethoxy. Silane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N, N′-bis- [3- (trimethoxysilyl) ) 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′-bi - [3- (triethoxysilyl) propyl] hexamethylenediamine. These aminosilane coupling agents may be used alone or in combination of two or more.

  Among these, aminosilane coupling agents include 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and N- (2-aminoethyl) -3-aminopropyltriethoxy. Silane is preferred, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane is more preferred, and N- (2-aminoethyl) -3-aminopropyltrimethoxysilane is particularly preferred. preferable.

  Content of the aminosilane coupling agent in an adhesive composition is 0.5-5 mass parts with respect to 100 mass parts of polyoxyalkylene polymers, and 1-4 mass parts is preferable. When the content of the aminosilane coupling agent in the adhesive composition is 0.5 parts by mass or more, the cured product of the adhesive composition has excellent extensibility and excellent adhesion to organic materials. Have When the content of the aminosilane coupling agent in the adhesive composition is 5 parts by mass or less, a cured product obtained by curing the adhesive composition has excellent elongation.

[Silanol condensation catalyst]
Silanol condensation catalysts include dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis (dibutyltin lauric acid) oxide, dibutyltin bis (acetylacetonate), dibutyltin bis (monoester maleate) , Tin octylate, dibutyltin octoate, dioctyltin oxide, dibutyltin bis (triethoxysilicate), dioctyltin dilaurate, bis (dibutyltin bistriethoxysilicate) oxide, dibutyltin oxybisethoxysilicate, and 1,1,3,3 Organotin compounds such as 3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane; organotitanium compounds such as tetra-n-butoxy titanate and tetraisopropoxy titanate; 1 5,7-triazabicyclo [4.4.0] deca5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] dec-5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 6-dibutylamino-1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5-diazabicyclo [4.3.0] non- Cycloamidine compounds such as 5-ene; dibutylamine-2-ethylhexoate and the like, and organic tin compounds are preferable, 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl- Distanoxane is more preferred. Other acidic catalysts and basic catalysts can also be used as the silanol condensation catalyst.

  Content of the silanol condensation catalyst in an adhesive composition is 0.1-3 mass parts with respect to 100 mass parts of polyoxyalkylene type polymers, 0.5-3.0 mass parts is preferable. 0-2.0 mass parts is more preferable. When the content of the silanol condensation catalyst is 0.1 parts by mass or more, the curability of the adhesive composition is improved. When the content of the silanol condensation catalyst is 3 parts by mass or less, the silanol condensation catalyst remaining in the cured product obtained by curing the adhesive composition can be inhibited from affecting the physical properties of the cured product.

[Polypropylene glycol]
It is preferable that the adhesive composition further contains polypropylene glycol. Polypropylene glycol does not contain a crosslinkable silyl group. Since the crosslinkable silyl group is the same as described above, the description thereof is omitted. By containing polypropylene glycol in the adhesive composition, the cured product of the adhesive composition has excellent elongation.

  1000-30000 is preferable and, as for the number average molecular weight of polypropylene glycol, 2000-5000 are more preferable. When the number average molecular weight of polypropylene glycol is 1000 or more, the cured product of the adhesive composition has excellent extensibility. When the number average molecular weight of the polypropylene glycol is 30000 or less, the cured product obtained by curing the adhesive composition has excellent elongation and can reduce the viscosity of the adhesive composition. The handleability of the agent composition can be improved. The number average molecular weight of polypropylene glycol refers to a value measured in the same manner as the number average molecular weight of the polyoxyalkylene polymer.

  10-100 mass parts is preferable with respect to 100 mass parts of polyoxyalkylene polymers, and, as for content of polypropylene glycol in an adhesive composition, 15-90 mass parts is more preferable. When the content of polypropylene glycol in the adhesive composition is 10 parts by mass or more, the cured product of the adhesive composition has excellent elongation. When the content of polypropylene glycol in the adhesive composition is 100 parts by mass or less, the adhesive composition has excellent adhesiveness.

  As long as the physical properties of the adhesive composition are not impaired, dehydrating agents, fillers, anti-sagging agents, anti-aging agents, epoxy resins, antioxidants, ultraviolet absorbers, plasticizers, pigments, solvents, fragrances, etc. It may be contained.

[Dehydrating agent]
It is preferable that the adhesive composition 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 contained in the air.

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

  The content of the dehydrating agent in the adhesive composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 10 parts by mass, and 1 to 5 parts by mass with respect to 100 parts by mass of the polyoxyalkylene polymer. Particularly preferred. The storage stability of an adhesive composition can be improved as content of the dehydrating agent in an adhesive composition is 0.5 mass part or more. When the content of the dehydrating agent in the adhesive composition is 20 parts by mass or less, the curability of the adhesive composition is improved.

[Filler]
The adhesive composition preferably further contains a filler. Examples of the filler include calcium carbonate, hydrous silicic acid, anhydrous silicic acid, calcium silicate, silica, titanium dioxide, clay, talc, carbon black, glass balloon, etc., preferably calcium carbonate, and colloidal calcium carbonate. More preferred. A filler may be used independently or 2 or more types may be used together.

[Plasticizer]
The adhesive composition may contain a plasticizer. Plasticizers include: dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dinormal hexyl phthalate, bis (2-ethylhexyl) phthalate, dinormal octyl phthalate, diisononyl phthalate, dinonyl phthalate, Phthalates such as diisodecyl phthalate, diisoundecyl phthalate, and bisbutylbenzyl phthalate; non-aromatic dibasic esters such as dioctyl adipate, dioctyl sebacate, dibutyl sebacate, and isodecyl succinate; butyl oleate; And aliphatic esters such as methyl acetylricinoleate; esters of polyalkylene glycols such as diethylene glycol dibenzoate, triethylene glycol dibenzoate, and pentaerythritol ester; Tricresyl phosphate, and phosphoric acid esters such as tributyl phosphate. These plasticizers may be used alone or in combination of two or more.

  Among these, as the plasticizer, phthalic acid esters are preferably used, and diisodecyl phthalate and diisononyl phthalate are more preferable.

  10-100 mass parts is preferable with respect to 100 mass parts of polyoxyalkylene polymers, and, as for content of the plasticizer in an adhesive composition, 20-70 mass parts is more preferable. When the content of the plasticizer in the adhesive composition is 10 parts by mass or more, a cured product obtained by curing the adhesive composition has excellent elongation. When the content of the plasticizer in the adhesive composition is 100 parts by mass or less, a cured product obtained by curing the adhesive composition is tough and preferable.

[Weatherproof stabilizer]
The adhesive composition preferably further includes a weathering stabilizer. Preferred examples of the weathering stabilizer include an antioxidant, an ultraviolet absorber, and a light stabilizer. By using these weather resistance stabilizers, the weather resistance of the cured product of the adhesive composition can be improved. A weathering stabilizer may be used independently or 2 or more types may be used together.

  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 the hindered phenol antioxidant include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (melting point: 118 ° C.), octadecyl-3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate] (melting point 52 ° C.), and N, N′-hexane-1,6-diylbis [3- (3,5-di-tert-butyl-4 -Hydroxyphenylpropionamide)] (melting point: 158 ° C.). Moreover, as a hindered phenolic antioxidant, commercial items, such as a brand name "IRGANOX (trademark) 1135" (melting | fusing point 5 degreeC) by BASF, can also be used.

  The content of the antioxidant in the adhesive composition is preferably 0.1 to 20 parts by mass, more preferably 0.3 to 10 parts by mass with respect to 100 parts by mass of the polyoxyalkylene polymer. ˜5 parts by mass is particularly preferred.

  Examples of ultraviolet absorbers include benzotriazole ultraviolet absorbers and benzophenone ultraviolet absorbers. Of these, benzotriazole-based ultraviolet absorbers are preferred. Specific examples of the benzotriazole ultraviolet absorber include 2- (2H-benzotriazol-2-yl) -p-cresol (melting point 130 ° C.), 2- (2H-benzotriazol-2-yl) -4- 6-bis (1-methyl-1-phenylethyl) phenol (melting point 139 ° C.), 2- [5-chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol (Melting point 139 ° C.), 2- (2H-benzotriazol-2-yl) -4,6-di-tert-pentylphenol (melting point 84 ° C.), and 2- (2H-benzotriazol-2-yl) -4 -(1,1,3,3-tetramethylbutyl) phenol (melting point 104 ° C.) and the like. Moreover, as a benzotriazole type ultraviolet absorber, commercial items, such as a brand name "TINUVIN (trademark) 384-2" (melting | fusing point 10 degrees C or less) made from BASF, can also be used.

  The content of the ultraviolet absorber in the adhesive composition is preferably 0.1 to 20 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the polyoxyalkylene polymer. ˜5 parts by mass is particularly preferred.

  Examples of the light stabilizer include hindered amine light stabilizers. Specifically, a mixture of bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate (melting point: 10 ° C. or lower) ), Dibutylamine, 1,3,5-triazine, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N- (2,2, Polycondensation product with 6,6-tetramethyl-4-piperidyl) butylamine (melting point 135 ° C.), poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine -2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] (melting point 118 ° C), dimethyl succinate Such as polycondensates of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (mp 63 ° C.) and the like.

  The content of the light stabilizer in the adhesive composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 10 parts by mass, and 1 to 5 parts by mass with respect to 100 parts by mass of the polyoxyalkylene polymer. Is particularly preferred.

  In addition to the components described above, the adhesive composition may contain other additives such as a thixotropic agent, a pigment, a dye, and an anti-settling agent. The adhesive composition may contain a small amount of a solvent as long as the effect is not impaired. Other additives and solvents may be used alone or in combination of two or more.

  Any thixotropic agent may be used as long as it can cause the adhesive composition to exhibit thixotropic properties. Preferred examples of the thixotropic agent include hydrogenated castor oil, fatty acid bisamide, and fumed silica.

  The content of the thixotropic agent in the adhesive composition is preferably from 0.1 to 200 parts by weight, more preferably from 1 to 150 parts by weight, based on 100 parts by weight of the polyoxyalkylene polymer. When the content of the thixotropic agent in the adhesive composition is 0.1 parts by mass or more, excellent thixotropy can be imparted to the adhesive composition. When the content of the thixotropic agent in the adhesive composition is 200 parts by mass or less, the viscosity of the adhesive composition is suppressed from becoming too high, and the adhesive composition has excellent handleability.

  In the adhesive composition, the crosslinkable silyl group of the polyoxyalkylene polymer is hydrolyzed and dehydrated and condensed by moisture in the air or moisture contained in the adherend to form a siloxane bond. It hardens | cures by forming and forms hardened | cured material excellent in elongation property, alkali resistance, and adhesive force. The use of the adhesive composition is not particularly limited, but the adhesive composition can exhibit excellent elongation properties, alkali resistance and adhesive strength after curing, and therefore is suitable for bonding and integrating an outer wall finish on a concrete surface. Used. Specifically, after the adhesive composition is applied to the concrete surface, the outer wall finishing material is laminated on the applied adhesive composition, and these are left to cure to cure the adhesive composition. By doing so, a cured product (adhesive layer) is formed. Thereby, the building structure in which the outer wall finishing material is bonded and integrated on the concrete surface via the adhesive layer obtained by curing the adhesive composition is obtained. As the outer wall finishing material, for example, an inorganic material such as mortar, tile, brick, porcelain and stone, or an organic material formed from a synthetic resin such as polyvinyl chloride or polyethylene terephthalate is used.

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

Each component used in the examples and comparative examples will be described.
[Polyoxyalkylene polymer]
-A polyoxyalkylene polymer in which the main chain skeleton is polyoxypropylene and has a methoxysilyl group at the end of the main chain skeleton (number average number of methoxysilyl groups per molecule: 1.2, number Average molecular weight: 20000, polyoxypropylene chain not containing urethane bond, product name “MS Polymer S-203” manufactured by Kaneka Corporation)
[Magnesium oxide]
Magnesium oxide (average particle size: 50 μm, trade name “Kyowa Mug # 150” manufactured by Kyowa Chemical Co., Ltd.)
[Zinc oxide]
・ Zinc oxide (trade name “Zinc Hana AZO” manufactured by Shodo Chemical Industry Co., Ltd.)
[Aminosilane coupling agent]
N- (2-aminoethyl) -3-aminopropyltrimethoxysilane (trade name “KBM-603” manufactured by Shin-Etsu Chemical Co., Ltd.)
[Epoxysilane coupling agent]
・ 3-Glycidoxypropyltriethoxysilane (trade name “KBM403” manufactured by Shin-Etsu Chemical Co., Ltd.)
[Silanol condensation catalyst]
1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane (trade name “Neostan U-130” manufactured by Nitto Kasei Co., Ltd.)
[Polypropylene glycol]
Polypropylene glycol (number average molecular weight: 3000, trade name “P-3000” manufactured by Asahi Denka Co., Ltd.)
[Dehydrating agent]
・ Vinyltrimethoxysilane (trade name “NUC Silicone A171” manufactured by Nippon Unica Co., Ltd.)
〔Antioxidant〕
Pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]
[Filler]
・ Colloidal calcium carbonate (trade name “CCR” manufactured by Shiroishi Kogyo Co., Ltd.)

(Examples 1-9, Comparative Examples 1-8)
Predetermined amounts of polyoxyalkylene polymers shown in Table 1 and Table 2, magnesium oxide, zinc oxide, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane (aminosilane coupling agent), 3-glycol Sidoxypropyltriethoxysilane (epoxysilane coupling agent), 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane (silanol condensation catalyst), polypropylene glycol, vinyltrimethoxysilane (dehydrating agent) ), A raw material composition containing pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (antioxidant) and colloidal calcium carbonate (filler) was supplied to a stirrer. Next, after the inside of the stirrer was sealed, the raw material composition was uniformly mixed under reduced pressure to obtain an adhesive composition.

  About the obtained adhesive composition, elongation property and adhesive strength were measured in the following manner, and the results are shown in Tables 1 and 2.

(Elongation)
The extensibility of the adhesive composition was measured according to JIS A5557.

(Adhesive strength)
In accordance with JIS A5557, the standard mortar test piece and the porcelain mosaic tile were bonded and integrated with the adhesive composition, and the adhesive strength after standard curing and after alkaline hot water immersion treatment was measured. The measurement results are shown in the column of “Porcelain mosaic tile” of “Adhesive strength”.

  Furthermore, in accordance with JIS A5557, the standard mortar test piece and the hard polyvinyl chloride tile-shaped test piece were bonded and integrated with the adhesive composition, and after the standard curing and after the alkaline hot water immersion treatment, the adhesive strength Was measured. The measurement results are shown in the “Polyvinyl chloride” column of “Adhesive strength”.

Claims (2)

100 parts by mass of a polyoxyalkylene polymer having 0.5 to 2 crosslinkable silyl groups on an average per molecule;
5 to 100 parts by mass of magnesium oxide having an average particle size of 10 to 150 μm ;
0.5 to 5 parts by mass of an aminosilane coupling agent,
An adhesive composition comprising 0.1 to 3 parts by mass of a silanol condensation catalyst.   The adhesive composition according to claim 1, further comprising 10 to 100 parts by mass of polypropylene glycol with respect to 100 parts by mass of the polyoxyalkylene polymer.