JP7403145B2 - Moisture curable composition - Google Patents

Description

The present invention relates to moisture curable compositions.

In a modified silicone-based curable composition containing a polyoxyalkylene polymer having a crosslinkable silyl group, the crosslinkable silyl group forms a crosslinked structure through condensation polymerization while being hydrolyzed with moisture in the atmosphere as necessary. It is widely used in sealants, adhesives, paints, etc. because it is safe because it does not emit toxic substances during curing, and has elasticity and durability after curing.

Modified silicone compositions that are cured by atmospheric moisture have a curing reaction rate that is greatly affected by the outside temperature, and a decrease in the curing rate is particularly problematic in low-temperature environments.

Therefore, a method using a trialkoxysilyl group as a crosslinkable silyl group (Patent Document 1), a method using a silicon compound having an Si--F bond (Patent Document 2), and the like have been proposed.

Patent No. 6290785 JP 2015-38196 Publication

However, although the curing speed at low temperatures can be improved by using the above-mentioned method, the curing speed becomes too fast under normal and high temperature environments, resulting in another problem of short pot life and poor workability. Therefore, in the above method, a problem arises in that the composition needs to be changed in accordance with the outside temperature of the environment in which the moisture-curable composition is used.

In view of the above-mentioned drawbacks, the object of the present invention is to provide a product that is less affected by outside temperature, has excellent curability and storage stability in both low- and high-temperature environments, and has a sufficient pot life. To provide a moisture-curable composition which has excellent workability.

The moisture-curable composition of the present invention is characterized by containing 100 parts by mass of a polyoxyalkylene polymer having a crosslinkable silyl group and 0.5 to 30 parts by mass of a water-soluble polymer.

[Polyoxyalkylene polymer having crosslinkable silyl group]
The moisture-curable composition contains a polyoxyalkylene polymer (hereinafter sometimes simply referred to as "polyoxyalkylene polymer") having a crosslinkable silyl group at the end. The main chain of the polyoxyalkylene polymer is preferably a polymer containing repeating units represented by general formula (1).
-(R ¹ -O) _n - (1)
(In the formula, R ¹ represents an alkylene group having 1 to 14 carbon atoms, and n is the number of repeating units and is a positive integer.)

The main chain of the polyoxyalkylene polymer may consist of only one type of repeating unit, or may consist 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. Examples include polymers, and polyoxypropylene is preferred.

Examples of crosslinkable silyl groups include silicon-containing groups having a hydrolyzable group bonded to a silicon atom or silanol groups, which can be condensed in the presence of moisture or a crosslinking agent, using a catalyst as necessary. A group that causes a reaction. Note that the silanol group means a hydroxy group (≡Si-OH) directly bonded to a silicon atom.

Examples of the crosslinkable silyl group include monoalkoxysilyl groups such as methoxysilyl group, ethoxysilyl group, dimethylmethoxysilyl group, and dimethylethoxysilyl group; and dimethoxysilyl groups such as dimethoxysilyl group, methyldimethoxysilyl group, and methyldiethoxysilyl group. Examples include trialkoxysilyl groups such as alkoxysilyl groups, trimethoxysilyl groups, and triethoxysilyl groups, and halogenated silyl groups to which a halogen is bonded such as trichlorosilyl groups, with dialkoxysilyl groups being preferred and dimethoxysilyl groups being preferred.

The number average molecular weight of the polyoxyalkylene polymer is preferably 8,000 to 50,000. When the number average molecular weight of the polyoxyalkylene polymer is 8,000 or more, the viscosity of the moisture-curable composition is stabilized and storage stability is improved. When the number average molecular weight of the polyoxyalkylene polymer is 50,000 or less, , the coating properties of the moisture-curable composition are excellent.

The molecular weight distribution [weight average molecular weight (Mw)/number average molecular weight (Mn)] of the polyoxyalkylene polymer is preferably 1.6 or less, more preferably 1.5 or less. When the molecular weight distribution is within the above range, the viscosity of the moisture-curable composition becomes low, and the moisture-curable composition has excellent curability in both low-temperature and high-temperature environments.

In the present invention, the number average molecular weight and weight average molecular weight of the polyoxyalkylene polymer having a crosslinkable silyl group are values measured by GPC (gel permeation chromatography) in terms of polystyrene. Specifically, 6 to 7 mg of a polyoxyalkylene polymer having a crosslinkable silyl group is collected, the collected polyoxyalkylene polymer is supplied to a test tube, and 0.05% by mass of the polyoxyalkylene polymer is added to the test tube. A diluted solution is prepared by adding an o-DCB (orthodichlorobenzene) solution containing BHT (dibutylhydroxytoluene) to dilute the polyoxyalkylene polymer to a concentration of 1 mg/mL.

The diluted solution was shaken using a dissolution filtration device at 145°C and a rotational speed of 25 rpm for 1 hour to dissolve the polyoxyalkylene polymer in the o-DCB solution containing BHT and prepare it as a measurement sample. do. Using this measurement sample, the number average molecular weight and weight average molecular weight of the polyoxyalkylene polymer can be measured by the GPC method.

The number average molecular weight and weight average molecular weight of a polyoxyalkylene polymer having a crosslinkable silyl group can be measured, for example, using the following measuring device and measuring conditions.
Measuring device manufactured by TOSOH, product name “HLC-8121GPC/HT”
Measurement conditions Column: TSKgelGMHHR-H(20)HT x 3
TSKguardcolumn-HHR(30)HT×1 piece
Mobile phase: o-DCB 1.0mL/min
Sample concentration: 1mg/mL
Detector: Blyth type refractometer
Standard material: Polystyrene (manufactured by TOSOH, molecular weight: 500-8420000)
Elution conditions: 145℃
SEC temperature: 145℃

Commercially available polyoxyalkylene polymers containing crosslinkable silyl groups can be used. As the polyoxyalkylene polymer having a crosslinkable silyl group, any polyoxyalkylene polymer having a crosslinkable silyl group can be used without particular limitation. It is a liquid substance before curing, and forms good rubber elasticity after curing. Therefore, it has a main chain skeleton of polyoxypropylene, a dimethoxysilyl group as a crosslinkable silyl group at the end of the main chain skeleton, and a urethane bond. It is preferable to use a polyoxypropylene polymer that does not have. A polyoxypropylene polymer whose main chain skeleton is polyoxypropylene, has a dimethoxysilyl group as a crosslinkable silyl group at the end of the main chain skeleton, and does not have a urethane bond is manufactured by Kaneka under the trade name " Examples include "Cyryl EST280", product names "Excester 6250" and "Excester 4530" manufactured by AGC Corporation.

[Water-soluble polymer]
Moisture-curable compositions contain water-soluble polymers. Water-soluble polymer refers to a polymer that is soluble in water. Specifically, the water-soluble polymer refers to a polymer whose Ext (water-soluble content) defined by ERT470.2-02 is 50% by mass or more.

ERT is an abbreviation for EDANA Recommended Test Methods, and is a European standard that defines a method for measuring water-absorbing polymers, and is often used as a global standard. Among them, 470.2-02 specifies Ext (Extractables: water-soluble content), and states that if Ext is 0 to 50% by mass or less, it is water-insoluble. That is, if Ext is greater than 50% by mass, it is water-soluble.

The Ext evaluation method is to add 1.0 g of polymer to 200 ml of 0.9% by mass sodium chloride aqueous solution, stir at 500 rpm for 16 hours, then measure by pH titration, and calculate the amount of polymer dissolved from the value obtained. (mass%) is calculated.

Water-soluble polymers are not particularly limited, and include, for example, starch, polyethylene oxide, polyethyleneimine, sodium polyacrylate, polyacrylamide, carboxymethylcellulose and its salts, polyvinyl alcohol, polyvinylpyrrolidone, and the like. The water-soluble polymers may be used alone or in combination of two or more. The water-soluble polymer has excellent curability in both low-temperature and high-temperature environments, so polyvinyl alcohol, carboxymethyl cellulose, and its salts are preferred, polyvinyl alcohol is more preferred, and polyvinyl alcohol with a saponification degree of 80 mol% or more is preferred. is particularly preferred. It is preferable that the degree of saponification is 80 mol % or more because it has excellent curability both in low-temperature and high-temperature environments.

The form of the water-soluble polymer is not particularly limited, but particulate form is preferred. The particle diameter of the water-soluble polymer is preferably 500 μm or less, more preferably 400 μm or less, more preferably 300 μm or less, and particularly preferably 200 μm or less. The particle diameter of the water-soluble polymer refers to a value measured in accordance with the sieving test method for chemical products specified in JIS K0069.

Commercially available water-soluble polymers can be used. Commercially available water-soluble polymers include Nippon Shokubai Co., Ltd. under the trade name "Epomin" (polyethyleneimine) and "Aqualic" (sodium polyacrylates), Sumitomo Seika Co., Ltd. under the trade name "PEO" (polyethylene oxide). ), the product name "JF-17S" (polyvinyl alcohol) manufactured by Nippon Ace Vine & Poval Co., Ltd., the product name "Celogen" (carboxymethylcellulose salt) and the product name "Pitzcor" (polyvinylpyrrolidone), manufactured by Daiichi Kogyo Seiyaku Co., Ltd. These can be suitably used.

The content of the water-soluble polymer in the moisture-curable composition is preferably 0.5 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of the polyoxyalkylene polymer having a crosslinkable silyl group. preferable. When the content of the water-soluble polymer is 0.5 parts by mass or more, the moisture-curable composition has excellent curability even in a low-temperature environment. When the content of the water-soluble polymer is 30 parts by mass or less, the storage stability of the moisture-curable composition is improved, and sufficient pot life is ensured without impairing the curability of the moisture-curable composition. Can be done.

[Inorganic filler]
The moisture-curable composition may contain inorganic fillers. By containing an inorganic filler in the moisture-curable composition, the strength of the cured product of the moisture-curable composition is improved.

By using an inorganic filler and a polyoxyalkylene polymer having a crosslinkable silyl group, the cured product of the moisture-curable composition is prevented from becoming too flexible, and the cured product has appropriate mechanical strength and It can impart rubber elasticity and can impart excellent adhesiveness and peelability to the moisture-curable composition.

Inorganic fillers are not particularly limited, and include, for example, calcium carbonate, magnesium carbonate, calcium oxide, hydrated silicic acid, anhydrous silicic acid, finely powdered silica, calcium silicate, titanium dioxide, clay, talc, carbon black, and glass. Examples include balloons, calcium carbonate is preferred, and ground calcium carbonate is more preferred. Note that the inorganic fillers may be used alone or in combination of two or more kinds.

The content of the inorganic filler in the moisture-curable composition is preferably 50 to 400 parts by mass, more preferably 80 to 350 parts by mass, based on 100 parts by mass of the polyoxyalkylene polymer having a crosslinkable silyl group. Particularly preferred is 100 to 300 parts by weight. When the content of the inorganic filler is 50 parts by mass or more, the strength of the cured product of the moisture-curable composition is improved. When the content of the inorganic filler is 400 parts by mass or less, the viscosity of the moisture-curable composition decreases, and the coatability of the moisture-curable composition improves.

[Silane coupling agent]
The moisture-curable composition may further contain a silane coupling agent. By containing the silane coupling agent, excellent adhesiveness can be imparted to the moisture-curable composition.

Examples of the silane coupling agent include an aminosilane coupling agent, an epoxysilane coupling agent, an isocyanate silane coupling agent, a mercaptosilane coupling agent, a carboxysilane coupling agent, a halogen silane coupling agent, a carbamate silane coupling agent, Examples include alkoxysilane coupling agents and acid anhydride silane coupling agents. The silane coupling agents may be used alone or in combination of two or more. The silane coupling agent is preferably an aminosilane coupling agent or an epoxysilane coupling agent because they improve the adhesiveness and water resistance of the moisture-curable composition.

As the aminosilane coupling agent, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N- (2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, 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-( Examples include trimethoxysilyl)propyl]hexamethylenediamine, N,N'-bis-[3-(triethoxylyl)propyl]hexamethylenediamine, and the like.

As the aminosilane coupling agent, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-propyltriethoxysilane are preferred. More preferred is N-(2-aminoethyl)-3-aminopropyltrimethoxysilane.

The epoxysilane coupling agent means a compound containing a silicon atom to which an alkoxy group is bonded in one molecule and a functional group containing an epoxy group. The epoxysilane coupling agent is not particularly limited, and examples include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropyltrimethoxysilane. Examples include propylethyldiethoxysilane and 2-(3,4epoxycyclohexyl)ethyltrimethoxysilane, with 3-glycidoxypropyltriethoxysilane being preferred.

The content of the silane coupling agent in the moisture-curable composition is preferably 0.5 to 20 parts by mass, and 1 to 18 parts by mass based on 100 parts by mass of the polyoxyalkylene polymer having a crosslinkable silyl group. More preferably, 1.5 to 15 parts by mass is particularly preferred.

[Silanol condensation catalyst]
The moisture curable composition may contain a silanol condensation catalyst. A silanol condensation catalyst is a catalyst for promoting a condensation reaction between crosslinkable silyl groups contained in a polyoxyalkylene polymer.

Examples of the silanol condensation catalyst include dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis(dibutyltin lauric acid) oxide, dibutyltin bis(acetylacetonate), and dibutyltin bis(monoester monoester). tin octylate), dibutyltin octoate, dioctyltin oxide, dibutyltin bis(triethoxysilicate), dioctyltin bis(triethoxysilicate), dioctyltin dilaurate, bis(dibutyltin bistriethoxysilicate) oxide, and dibutyltin Organotin compounds such as oxybisethoxysilicate; Organotitanium compounds such as tetra-n-butoxytitanate and tetraisopropoxytitanate; 1,5,7-triazabicyclo[4.4.0]decar-5-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]noner-5-ene, and other cycloamidine compounds; dibutylamine-2-ethylhexoate, etc. can be mentioned. Further, other acidic catalysts and basic catalysts can also be used as the silanol condensation catalyst. These silanol condensation catalysts may be used alone or in combination of two or more.

Among these, as the silanol condensation catalyst, organic tin compounds are preferable, and dibutyltin bis(triethoxysilicate) is more preferable, since the moisture-curable composition can be uniformly cured.

The content of the silanol condensation catalyst in the moisture-curable composition is preferably 0.1 to 10 parts by mass, and 0.5 to 6 parts by mass, based on 100 parts by mass of the polyoxyalkylene polymer having a crosslinkable silyl group. is particularly preferred. When the content of the silanol condensation catalyst is 0.1 parts by mass or more, the curability of the moisture-curable composition improves. When the content of the silanol condensation catalyst is 10 parts by mass or less, the storage stability of the moisture-curable composition is improved.

[Dehydrating agent]
Preferably, the moisture-curable composition contains a dehydrating agent. According to the dehydrating agent, when the moisture-curable composition is stored, it is possible to suppress the moisture-curable composition from being cured by moisture contained in the air or the like.

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

The content of the dehydrating agent in the moisture-curable composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, based on 100 parts by mass of the polyoxyalkylene polymer having a crosslinkable silyl group. , 1 to 7 parts by mass are particularly preferred. When the content of the dehydrating agent is 0.5 parts by mass or more, the storage stability of the moisture-curable composition is improved. When the content of the dehydrating agent is 20 parts by mass or less, the storage stability and handleability of the moisture-curable composition are improved.

[Other additives]
Moisture-curable compositions may also contain other additives such as plasticizers, antioxidants, ultraviolet absorbers, light stabilizers, pigments, dyes, antisettling agents, and the like. Among these, plasticizers and antioxidants are preferred.

The plasticizer is not particularly limited, and includes, for example, phthalate esters such as dibutyl phthalate, di(2-ethylhexyl) phthalate, diisononyl phthalate, diisodecyl phthalate, and butylbenzyl phthalate; dioctyl adipate, dioctyl sebacate, dibutyl sebacate, Non-aromatic dibasic acid esters such as isodecyl succinate; aliphatic esters such as butyl oleate and methyl acetylrisilinolate; esters of polyalkylene glycols such as diethylene glycol dibenzoate, triethylene glycol dibenzoate, and pentaerythritol ester. Phosphate esters such as tricresyl phosphate and tributyl phosphate; Trimellitic acid esters; Polybutadiene, polybutene, polyisobutylene, butadiene-acrylonitrile, polychloroprene; Chlorinated paraffins; Alkyldiphenyl, partially hydrogenated terphenyl, etc. hydrocarbon oils; process oils; polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; polyethers such as derivatives in which the hydroxyl groups of polyether polyols are converted to ester groups, ether groups, etc.; epoxidation Epoxy plasticizers such as soybean oil and benzyl epoxy stearate; dibasic acids such as sebacic acid, adipic acid, azelaic acid, and phthalic acid, and dibasic acids such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, and dipropylene glycol. Examples include polyester plasticizers obtained from alcohols; vinyl polymers obtained by polymerizing vinyl monomers including acrylic plasticizers by various methods. Note that the plasticizers may be used alone or in combination of two or more kinds.

The content of the plasticizer in the moisture-curable composition is preferably 20 to 100 parts by weight, more preferably 25 to 50 parts by weight, based on 100 parts by weight of the polyoxyalkylene polymer having a crosslinkable silyl group. When the content of the plasticizer is 20 parts by mass or more, the coatability of the moisture-curable composition improves. When the content of the plasticizer is 100 parts by mass or less, the mechanical strength of the cured product of the moisture-curable composition is improved.

Examples of the antioxidant include hindered phenolic antioxidants, monophenolic antioxidants, bisphenol antioxidants, and polyphenol antioxidants, with hindered phenolic antioxidants being preferred. The content of the antioxidant in the moisture-curable composition is preferably 0.1 to 20 parts by mass, and 0.3 to 10 parts by mass based on 100 parts by mass of the polyoxyalkylene polymer having a crosslinkable silyl group. is more preferable.

The moisture-curable composition can be produced by a method of mixing a polyoxyalkylene polymer having a crosslinkable silyl group, a water-soluble polymer, and, if necessary, additives. Mixing is preferably carried out under reduced pressure, and the moisture-curable composition is preferably stored in a sealed container to prevent reaction with moisture in the outside air.

Moisture-curable compositions are used, for example, in the construction of floor structures. When constructing a floor structure using a moisture-curable composition, the moisture-curable composition can ensure sufficient pot life in both low-temperature and high-temperature environments, and has excellent workability. Furthermore, the moisture-curable composition has excellent curability in both low-temperature and high-temperature environments, so after laminating the adherends together via the moisture-curable composition, It is rapidly cured by moisture and/or moisture in the adherends, and can firmly bond and integrate the adherends together.

The floor structure is constructed by bonding and integrating a floor finishing material onto a subfloor material laid on a floor base via a cured product made of a moisture-curable composition. The floor structure includes a floor base, a subfloor material laid on the floor base, and a moisture-curable composition formed on the subfloor material and adhesively integrated with the subfloor material. and a floor finishing material that is laid on the cured product and is adhesively integrated with the cured product.

Examples of the members constituting the floor finishing material include wood-based materials such as plywood and medium density fiberboard (MDF), tiles, vinyl chloride sheets, and stone, among which vinyl chloride It is preferable to use a thin, soft material like a sheet.

Examples of members constituting the flooring material include plywood, particle board, wood joists, gypsum board, slate board, and concrete board.

The moisture-curable composition of the present invention can maintain an appropriate pot life in both low-temperature environments in winter and high temperatures in summer, and is resistant to moisture in the air, adherends, etc., regardless of the outside temperature. It can exhibit good curing properties due to the moisture contained in it.

The moisture-curable composition of the present invention has excellent curability in both low-temperature environments in winter and high temperatures in summer, and can quickly bond and integrate adherends together by moisture-curing. let

The moisture-curable composition of the present invention becomes a strong cured product after moisture-curing, and when used as an adhesive, can provide strong adhesiveness and durability.

The embodiments of the present invention will be explained in more detail with reference to Examples below, but the present invention is not limited only to these Examples.

The following raw materials were used in the production of the moisture-curable compositions of Examples and Comparative Examples.

[Polyoxyalkylene polymer having crosslinkable silyl group]
・Polyoxyalkylene polymer with dimethoxysilyl group at the end of the main chain skeleton (polyoxypropylene) (number average molecular weight: 10,000, molecular weight distribution: 1.49, does not have urethane bonds, manufactured by Kaneka, product name "Silyl") EST280")

[Water-soluble polymer]
・Polyvinyl alcohol (saponification degree: 98 mol%, manufactured by Japan Vinyl Poval Co., Ltd., product name "JF-17S", particulate, particle size: 150 μm or less (#100 mesh full pass))
・Carboxymethylcellulose sodium (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name “Celogen BS”, particulate, particle size: 180 μm or less (#70 mesh full pass))

[Inorganic filler]
・Heavy calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., product name “Whiten SB”)

[Dehydrating agent]
・Vinyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name “KBM-1003”)

[Silanol condensation catalyst]
・Dibutyltin bis(triethoxysilicate) (manufactured by Nitto Kasei Co., Ltd., product name “Neostane S-303”)

(Examples 1-4, Comparative Examples 1-2)
A polyoxyalkylene polymer having a crosslinkable silyl group, a water-soluble polymer, an inorganic filler, a dehydrating agent, and a silanol condensation catalyst were mixed in the amounts shown in Table 1, and the mixture was heated under reduced pressure in a sealed stirrer. A moisture-curable composition was prepared by mixing the mixture until homogeneous.

In Table 1, the polyoxyalkylene polymer having a crosslinkable silyl group is simply written as "polyoxyalkylene polymer."

The obtained moisture-curable composition was evaluated for curability, storage stability, and pot life, and the results are shown in Table 1.

[Curability]
The moisture-curable composition was filled into a mold with a thickness of about 3 mm using a spatula, and the surface of the moisture-curable composition was smoothed. The measurement start point was when the surface of the moisture-curable composition had been smoothed. The surface was touched with a spatula, and the point at which the moisture-curable composition no longer adhered to the spatula was defined as the measurement end point. The time from the measurement start point to the measurement end point was calculated as the surface skinning time.

The surface skinning time was measured at ambient temperatures of 5°C and 23°C. The shorter the surface coating time, the better the curing properties. It can be determined that the smaller the difference between the surface skinning time at 5°C and the surface skinning time at 23°C, the less the moisture-curable composition is affected by the atmospheric temperature during curing.

[Storage stability]
The viscosity of the moisture-curable composition in an atmosphere of 23°C was measured in accordance with JIS K6833 using a B-type viscometer at a rotation speed of 10 rpm, and the viscosity of the moisture-curable composition obtained was determined as the "initial viscosity". ”.

After filling the cartridge with the moisture-curable composition, the air inside the cartridge was removed and the cartridge was sealed to be in a hermetically sealed state. After the sealed cartridge was left at 50° C. for 4 weeks, the cartridge was opened.

The viscosity of the moisture-curable composition in the cartridge in an atmosphere of 23°C was measured using a B-type viscometer at a rotation speed of 10 rpm in accordance with JIS K6833, and the viscosity of the moisture-curable composition obtained was measured. It was defined as "viscosity after storage." The viscosity change was calculated based on the following formula.
Viscosity change = Viscosity after storage / Initial viscosity

If the viscosity change is 1.5 or less, there is no problem in terms of storage stability, and if it exceeds 1.5, the storage stability may be poor and long-term storage may become difficult.

[Pot life]
The moisture-curable composition was applied onto the first plywood substrate using a comb trowel. Another second plywood was laminated on the surface coated with the moisture-curable composition, and a 1 kg weight was placed on the first plywood to press the plywood in a direction in which the plywood approached each other to prepare a test body. Forty test specimens were produced in the manner described above.

Next, immediately after the test pieces were prepared, the test pieces were selected one by one every 5 minutes, and the second plywood of the test piece was peeled off from the first plywood, so that the moisture-curable composition was transferred to the second plywood. Visual observation was made to see if there were any. The time when the moisture-curable composition was no longer transferred to the second plywood was defined as the pot life. Note that the above-mentioned measurement environment was 23° C. and 50% relative humidity.

Claims (3)

It is characterized by containing 100 parts by mass of a polyoxyalkylene polymer having a crosslinkable silyl group and 0.5 to 30 parts by mass of a water-soluble polymer that is particulate and has a particle size of 500 μm or less. Moisture-curable compositions (excluding moisture-curable compositions containing epoxy resins and ketimine compounds as latent curing agents). Moisture-curable composition according to claim 1, characterized in that the water-soluble polymer is polyvinyl alcohol. The moisture-curable composition according to claim 2, wherein the degree of saponification of the polyvinyl alcohol is 80 mol% or more.