JP2021187937A - Moisture-curable adhesive, cured product, and laminate - Google Patents

Abstract

To provide a moisture-curable adhesive which exhibits excellent breaking stress and elongation at break, a cured product thereof, and a laminate excellent in long-term durability using the adhesive.SOLUTION: There are provided: a moisture-curable adhesive containing a block polymer in which a urethane unit (A) and a polymer unit (B) of an ethylenically unsaturated monomer are linked by a residue of a chain transfer agent, the polymer unit (B) of the ethylenically unsaturated monomer having a constituent unit derived from an ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group; a cured product thereof; and a laminate using the adhesive.SELECTED DRAWING: None

Description

The present invention relates to moisture-curable adhesives, cured products, and laminates thereof.

Crosslinkable silyl group-containing polymers are widely used in the fields of sealing materials, adhesives, coating materials, etc. Among them, from the viewpoint of flexibility, hydrolyzable silyl groups are added to the molecular ends of polyether chains and acrylic chains. Modified silicone resins, which are polymers having, have been widely studied. (For example, Patent Documents 1 and 2).
However, although the modified silicone resins described in Patent Documents 1 and 2 show high elongation at break, they have a hydrolyzable silyl group only at the molecular end, so that the crosslink formation reaction at the time of curing is slow and the amount of crosslinks produced is large. There is a problem that the breaking stress of the obtained cured film is low because the amount is small.
On the other hand, for example, Patent Document 3 describes a reactive silicon group-containing polyoxyalkylene polymer having more than 1.0 reactive silyl groups for one terminal site and an average of 1.0 per molecule. It is described that a cured film having excellent elongation at break and breaking stress can be obtained by mixing and using a (meth) acrylic acid ester polymer having two or more reactive silyl groups.
However, the invention described in Patent Document 3 does not fully satisfy the requirement to obtain a cured product having excellent elongation at break and breaking stress.

Japanese Unexamined Patent Publication No. 2001-11298 Japanese Unexamined Patent Publication No. 2009-084366 International Publication No. 2016/002907

An object of the present invention is to provide a moisture-curable adhesive and a cured product thereof, which exhibit excellent breaking stress and breaking elongation, and a laminate having excellent long-term durability using the adhesive. do.

As a result of diligent research on the above-mentioned problems, the present inventor has found that the problem can be solved by using the moisture-curable adhesive described below, and has reached the present invention.

The first aspect of the present invention comprises a block polymer in which a urethane unit (A) and a polymer unit (B) of an ethylenically unsaturated monomer are linked by a residue of a chain transfer agent, and the ethylene is described. The present invention relates to a moisture-curable adhesive in which the polymer unit (B) of the sex-unsaturated monomer has a structural unit derived from the ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group.

Another aspect of the present invention relates to the moisture-curable adhesive, wherein the chain transfer agent is a compound having a functional group capable of reacting with an isocyanato group and a sulfanyl group.

Another aspect of the present invention relates to the moisture-curable adhesive, wherein the linking portion between the urethane unit (A) and the residue of the chain transfer agent has a urea bond.

In another aspect of the present invention, the ethylenically unsaturated monomer constituting the polymer unit (B) of the ethylenically unsaturated monomer has an ethylenically unsaturated monomer having a hydrolyzable silyl group ( The present invention relates to the moisture-curable adhesive containing b1) in the range of 5 to 100% by mass based on the total mass of the monomer.

In another aspect of the present invention, the block polymer contains the polymer unit (B) of the ethylenically unsaturated monomer in the range of 5 to 40% by mass based on the total mass of the block polymer. Regarding curable adhesives.

Another aspect of the present invention relates to a cured product obtained by curing the moisture-curable adhesive.

Another aspect of the present invention relates to a laminate having a layer made of the cured product on a substrate.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a moisture-curable adhesive and a cured product thereof, which exhibit excellent breaking stress and breaking elongation, and a laminate having excellent long-term durability using the adhesive.

<Block polymer>
The moisture-curable adhesive of the present invention contains a block polymer in which a urethane unit (A) and a polymer unit (B) of an ethylenically unsaturated monomer are linked by a chain transfer agent residue, and is said to be ethylenically. The polymer unit (B) of the unsaturated monomer is characterized by having a structural unit derived from the ethylenically unsaturated monomer (b1) having one or more hydrolyzable silyl groups.
The block polymer is obtained by comprising a flexible urethane unit (A) and a polymer unit (B) of an ethylenically unsaturated monomer having a hydrolyzable silyl group which is a moisture-curable crosslinking group. Moisture-curable adhesives can achieve not only flexibility but also high coating strength.

The block polymer of the present invention may have a structure in which the urethane unit (A) and the polymer unit (B) of the ethylenically unsaturated monomer are linked by a chain transfer agent residue, and the production method thereof is as long as it has a structure. Although not limited, it can be preferably produced by the following method.
First, the polyol and the polyisocyanate are reacted to form a urethane unit (A) having an isocyanato group at both ends (hereinafter, step 1).
Next, a chain transfer agent is added to synthesize a prepolymer having chain transfer agent residues at both ends of the urethane unit (A) (hereinafter, step 2).
Then, using the chain transfer agent residue of the obtained prepolymer, an ethylenically unsaturated monomer containing an ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group in the molecule is polymerized. Chain transfer polymerization is carried out in the presence of an initiator to form a polymer unit (B) of an ethylenically unsaturated monomer (hereinafter, step 3).
In this way, the polymer unit of the urethane unit (A) and the ethylenically unsaturated monomer having a structural unit derived from the ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group in the molecule. A block polymer linked with (B) by a chain transfer agent residue can be obtained.
All of these reactions may be carried out with or without a solvent. When a solvent is used, the solvent may be removed under reduced pressure or normal pressure in the middle of the reaction or after the reaction is completed.

<Urethane unit (A)>
The block polymer in the present invention has a structure in which a urethane unit (A) and a polymer unit (B) of an ethylenically unsaturated monomer are linked by a chain transfer agent residue, and the urethane unit ( A) can be formed by reacting a polyol and a polyisocyanate in a solvent-free or solvent-free manner.

<Polyol>
Examples of the polyol constituting the urethane unit (A) include a polyether polyol, a polyester polyol, a polycarbonate polyol, a polyolefin polyol, a vegetable oil-based polyol, and other polyols. These may be used individually by 1 type, or may be used in combination of 2 or more type.

(Polyether polyol)
Examples of the polyether polyol include polymers such as methylene oxide, ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran, or copolymers such as polyethylene glycol, polypropylene glycol, poly (ethylene / propylene) glycol, and polytetramethylene glycol. Glycols;
Condensates of hexanediol, methylhexanediol, heptanediol, octanediol or mixtures thereof;
Examples thereof include polyols obtained by adding an alkylene oxide such as methylene oxide, ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, or polyoxytetramethylene oxide to a compound having two or more active hydrogen groups.

Examples of the compound having two or more active hydrogen groups include low molecular weight polyols, aliphatic amine compounds, aromatic amine compounds, alkanolamines, bisphenols and the like.

Examples of the low molecular weight polyol include a bifunctional low molecular weight polyol and a trifunctional or higher functional low molecular weight polyol.

The bifunctional low molecular weight polyol is not particularly limited, and is, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4. -Butandiol, Neopentyl Glycol, Pentandiol, Hexanediol, Octanediol, Nonandiol, Dipropylene Glycol, Diethylene Glycol, Triethylene Glycol, 3-Methyl-1,5-Pentanediol, 2-Butyl-2-ethyl-1 , 3-Propanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, polyoxyethylene glycol (additional number of moles 10 or less), polyoxypropylene glycol (additional number of moles 10 or less) ), Cyclohexanediol, Cyclohexanedimethanol, Tricyclodecanedimethanol, Cyclopentadienedimethanol, Dimerdiol, Bisphenol A, N, N-bis (2-hydroxypropyl) aniline, Dimethylolacetic acid, Dimethylolpropionic acid, Dimethylolbutane Examples thereof include acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpentanoic acid, dihydroxysuccinic acid, dihydroxypropionic acid and dihydroxybenzoic acid.

The trifunctional or higher functional low molecular weight polyol is not particularly limited, and is, for example, trimethylolethane, trimethylolpropane, 1,1,1-trimethylolbutane, 1,2,3-butanetriol, 1,2,4-. Butantriol, 1,2,6-butanetriol, trimethylolpropane, trimethylolpentene, trimethylolhexene, trimethylolhepten, trimethylolpropane, trimethylolnonen, trimethylolpropane, trimethylolpropane, trimethyloldodecene , Trimethylolpolydecene, trimethylolpentadecene, trimethylolhexadecene, trimethylolheptadecene, trimethyloloctadecene, 1,1,1-trimethylol-2-methyl-hexane, 1,1,1-trimethylol-3 -Methyl-hexane, 1,1,1-trimethylol-2-ethyl-hexane, 1,1,1-trimethylol-3-ethyl-hexane, trimethylolhexene, 1,2,3-octanetriol, 1, 3,7-octanetriol, 3,7-dimethyl-1,2,3-octanetriol, 1,1,1-, 1,1,1-trimethylolpropane, 1,2,10-decantriol, 1, 1,1-trimethylolisoheptadecane, 1,1,1-trimethylol-sec-butane, 1,1,1-trimethylol-tert-pentane, 1,1,1-trimethylol-tert-nonan, 1, , 1,1-trimethylol-tert-tridecane, 1,1,1-trimethylol-tert-heptadecane, 1,1,1-trimethylol-2-methyl-hexane, 1,1,1-trimethylol-3 -Methyl-hexane, 1,1,1-trimethylol-2-ethyl-hexane, 1,1,1-trimethylol-3-ethyl-hexane, 1,1,1-trimethylolisoheptadecane, 1,2 , 3,4-Butantetraol, pentaerythritol, dipentaerythritol, tripentaerythritol, glycerin, diglycerin, triglycerin, polyglycerin, trimethylolethane, dimethylolpropane, tris (2-hydroxyethyl) isocyanurate, benzene -1,3,5-triol, benzene-1,2,3-triol, stilben-3,4', 5-triol, shoe cloth, inositol, sorbitan, sorbitol, mannitol, saccharose, cellulose, xylyl Thor is mentioned.

Examples of the aliphatic amine compounds include ethylenediamine, triethylenetetramine, diethylenetriamine, and triaminopropane. Examples of aromatic amine compounds include toluenediamine and diphenylmethane-4,4-diamine. Examples of alkanolamines include ethanolamine and diethanolamine. Examples of bisphenols include bisphenol A, bisphenol AP, bisphenol B, bisphenol C, bisphenol E, and bisphenol F.

(Polyester polyol)
Examples of the polyester polyol include a polyester polyol in which the above-mentioned low molecular weight polyol and a dibasic acid component are condensed and reacted.
Examples of the dibasic acid component include terephthalic acid, adipic acid, azelaic acid, sebatic acid, dimer acid, hydrogenated dimer acid, phthalic anhydride, isophthalic acid, trimellitic acid, glutaric acid, pimelic acid, suberic acid, and sebacic acid. Lipid or aromatic dibasic acids, and their anhydrides.

Further, as the polyester polyol, a polyester polyol obtained by ring-opening polymerization of a cyclic ester compound of lactones such as ε-caprolactone, poly (β-methyl-γ-valerolactone) and polyvalerolactone may be used.

(Polycarbonate polyol)
Examples of the polycarbonate polyol include those obtained by reacting the above-mentioned low molecular weight polyol with a carbonate compound such as a dialkyl carbonate, an alkylene carbonate, or a diallyl carbonate.
As the dialkyl carbonate, dimethyl carbonate, diethyl carbonate or the like can be used, ethylene carbonate or the like can be used as the alkylene carbonate, and diphenyl carbonate or the like can be used as the diaryl carbonate.

(Polyolefin polyol)
Examples of the polyolefin polyol include hydroxyl group-containing polybutadiene, hydrogenated hydroxyl group-containing polybutadiene, hydroxyl group-containing polyisoprene, hydrogenated hydroxyl group-containing polyisoprene, hydroxyl group-containing chlorinated polypropylene, and hydroxyl group-containing chlorinated polyethylene.

(Vegetable oil-based polyol)
Examples of the vegetable oil-based polyol include castor oil derived from plants, dimer acid, and polyols made from soybean oil.

The moisture-curable adhesive of the present invention is preferably used as a liquid solvent-free type from the viewpoint of safety and work environment, and is preferably a polyether polyol or a vegetable oil-based polyol, more preferably poly. It is an ether polyol, more preferably polypropylene glycol.

The number average molecular weight of the polyol is preferably 500 or more and 30,000 or less, and more preferably 2,000 or more and 10,000 or less.

The polyol may contain other polyols other than the above, and the above-mentioned low molecular weight polyols can be used in combination for the purpose of adjusting the urethane bond concentration and introducing various functional groups.

<Polyisocyanate>
Examples of the polyisocyanate constituting the urethane unit (A) include aromatic, aliphatic, and alicyclic diisocyanates. These may be used individually by 1 type, or may be used in combination of 2 or more type.

Examples of the aromatic diisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-phenylenedi isocyanate, p-phenylenedi isocyanate, 4,4'-diphenylmethane diisocyanate, and 2,4-diphenylmethane diisocyanate, 2 , 2'-Diphenylmethane diisocyanate, 1,5-naphthalenediocyanate, trizine diisocyanate, xylylene diisocyanate, m-tetramethylxylene diisocyanate, p-tetramethylxylene diisocyanate, 3,3'-dimethyl-4 , 4'-biphenylenediisocyanate, 3,3'-dimethoxy-4,4'-biphenylenediocyanate, 3,3'-dichloro-4,4'-biphenylenediocyanate, 1,5-tetrahydronaphthalenedi isocyanate.

Examples of the aliphatic diisocyanis include trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylenedisocyanate, 1,3-butyrenis diisocyanate, dodecamethylene diisocyanate, and 2). , 4,4-trimethylhexamethylene diisocyanis, lysine diisocyanis, lysine ester triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate tetramethylene diisocyanate, pentamethylene diisocyanate, trimethylhexamethylene Diisocyanate can be mentioned.

Examples of the alicyclic diisocyanate include isophorone diisocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexanediisocyanate, 1,4-cyclohexanediisocyanate, methyl-2,4-cyclohexanediisocyanate, and methyl-2,6-cyclohexane. Examples thereof include diisocyanate, 4,4'-methylenebis (cyclohexylisocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, hydrogenated xylylene diisocyanate, dimerate diisocyanate, and norbornene diisocyanate.

The reaction between the polyol and the polyisocyanate can be preferably carried out using a known urethanization reaction in the absence of a solvent, and by adding an excess of the polyisocyanate, a urethane unit having isocyanate groups at both ends can be obtained. can. The molar equivalent ratio (NCO molar number / OH molar number) between the isocyanate group and the hydroxyl group during the reaction is preferably 1.05 to 2.00, more preferably 1.10 to 1.70.
In the urethanization reaction, a catalyst may be used for the purpose of adjusting the reactivity.

(catalyst)
As the catalyst, known metal-based catalysts, amine-based catalysts and the like can be used. Metallic catalysts include dibutyltin dilaurate, tin octoate, dibutyltin di (2-ethylhexoate), 2-ethylhexoate lead, 2-ethylhexyl titanate, titanium ethylacetate, 2-ethylhexoate. Examples thereof include iron, 2-ethylhexoate cobalt, zinc naphthenate, cobalt naphthenate, tetra-n-butyl tin and the like. Examples of the amine-based catalyst include tertiary amines such as tetramethylbutanediamine. The amount of the catalyst used is preferably in the range of 0.05 to 1 mol% with respect to the polyol.

The number average molecular weight of the urethane unit (A) is not particularly limited, and is preferably in the range of 3,000 to 200,000. When it is 3,000 or more, the adhesiveness of the obtained cured product is excellent, and when it is 200,000 or less, the viscosity can be easily adjusted.

<Chain transfer agent>
By reacting the isocyanato groups at both ends of the urethane unit (A) obtained above with the chain transfer agent, a prepolymer having chain transfer agent residues at both ends can be obtained.
The chain transfer agent is not particularly limited, but preferably has a functional group capable of reacting with an isocyanato group and a sulfanil group. When the chain transfer agent is used, the terminal isocyanato group in the urethane unit (A) and the functional group capable of reacting with the isocyanato group in the chain transfer agent react to form a prepolymer having a sulfanyl group at both ends.
The reaction between the urethane unit and the chain transfer agent proceeds easily by mixing at an arbitrary temperature of 20 to 120 ° C., and the chain transfer agent is used alone or in combination of two or more of known chain transfer agents. be able to.

Examples of the functional group capable of reacting with the isocyanato group include a hydroxyl group or an amino group, and the hydrogen atom of the amino group may be substituted with an organic residue such as an alkyl group or an aryl group, and such a substituted amino may be used. Examples of the group include mono-substituted amino groups such as N-alkylamino group and N-arylamino group. Examples of the hydroxyl group include a primary hydroxyl group, a secondary hydroxyl group or a tertiary hydroxyl group.
The functional group capable of reacting with the isocyanato group is preferably an amino group because of its excellent reactivity with the isocyanato group. Since the amino group is more reactive than the sulfanyl group, it is preferable because it can preferentially react with the terminal isocyanato group of the urethane unit to form a urea bond and efficiently introduce the sulfanyl group to the terminal of the prepolymer. ..

Examples of the compound having one amino group and one sulfanyl group in the molecule include 2-aminoethanethiol, 3-aminopropyl-1-thiol, 1-aminopropyl-2-thiol, 4-amino-1-. Examples thereof include aminoalkanethiols such as butanethiol; aminobenzenethiols such as 2-aminothiophenol, 3-aminothiophenol, and 4-aminothiophenol; Among them, aminoalkanolthiols are preferable, and 2-aminoethanethiol is more preferable.

<Polymer unit (B) of ethylenically unsaturated monomer>
The polymer unit (B) of the ethylenically unsaturated monomer has a structural unit derived from the ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group in the molecule, and has a structural unit in the molecule. It is a structure obtained by polymerizing an ethylenically unsaturated monomer containing an ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group in the presence of a polymerization initiator.
Specifically, the prepolymer obtained in step 2 having chain transfer agent residues at both ends and the ethylenically unsaturated monomer (b1) having an ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group in the molecule are included. By polymerizing the saturated monomer in the presence of a polymerization initiator, the urethane unit (A) and the polymer unit (B) of the ethylenically unsaturated monomer are linked by a chain transfer agent residue. Block polymer can be obtained.

<Ethylene unsaturated monomer having a hydrolyzable silyl group (b1)>
Examples of the hydrolyzable silyl group of the monomer (b1) include an alkoxysilyl group such as a methoxysilyl group and an ethoxysilyl group, and the ethylenically unsaturated monomer (b1) having such a group is used. Is, for example, vinyl silanes such as vinyl trimethoxysilane, vinyl triethoxysilane, vinylmethyldimethoxysilane, allyltrimethoxysilane; (meth) acrylic acid-3- (trimethoxysilyl) propyl, (meth) acrylic acid-3. -(Triethoxysilyl) propyl, (meth) acrylate-3- (dimethoxymethylsilyl) propyl, (meth) acrylate-3- (diethoxymethylsilyl) propyl, (meth) acrylate-3- (dimethoxymethyl) Examples thereof include silyl group-containing (meth) acrylic acid esters such as silyl) methyl and (meth) acrylic acid-3- (diethoxymethylsilyl) methyl.

The ethylenically unsaturated monomer constituting the polymer unit (B) of the ethylenically unsaturated monomer is an ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group. It is preferably contained in the range of 5 to 100% by mass, more preferably in the range of 10 to 50% by mass, based on the total mass of the above. The range of 5 to 100% by mass is preferable because it is excellent in breaking stress and breaking elongation.

<Other ethylenically unsaturated monomers>
The ethylenically unsaturated monomer other than the ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group used in step 3 is any one that can be copolymerized with the monomer (b1). It is not particularly limited and can be appropriately selected from known ethylenically unsaturated monomers.
Examples of such ethylenically unsaturated monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth). ) Acrylate, tertiary butyl (meth) acrylate, isoamyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cetyl (meth) acrylate, decyl (meth) acrylate, isodecyl Linear or branched alkyl (meth) acrylates such as (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, isomyristyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate;
Cyclohexyl (meth) acrylate, tertiary butylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) ) Cyclic alkyl (meth) acrylates such as acrylates and isobornyl (meth) acrylates;
Fluoroalkyl (meth) acrylates such as trifluoroethyl (meth) acrylate, octafluoropentyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, and tetrafluoropropyl (meth) acrylate;
(Meta) acrylates having a heterocycle such as tetrahydrofurfuryl (meth) acrylate and 3-methyl-3-oxetanyl (meth) acrylate;
Benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, paracumylphenoxyethyl (meth) acrylate, paracumylphenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, etc. (Meta) acrylates having an aromatic ring of
Methoxypolyethylene glycol mono (meth) acrylate, octoxypolyethylene glycol polypropylene glycol mono (meth) acrylate, lauroxypolyethylene glycol mono (meth) acrylate, stearoxypolyethylene glycol mono (meth) acrylate, phenoxypolyethylene glycol mono (meth) acrylate, Phenoxy Polyethylene Glycol Polyethylene Glycol Mono (Meta) Acrylic, Polyethylene Glycol Monomethyl Ether (Meta) Acrylic, Lauroxy Polyethylene Glycol Mono (Meta) Acrylic, Nonyl Phenoxy Polyethylene Glycol Mono (Meta) Acrylic, Nonyl Phenoxy Polyethylene Glycol Mono (Meta) Acrylic, Nonylphenoxypolyethylene glycol polypropylene glycol mono (meth) acrylate, phenoxypolyethylene glycol mono (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, n-butoxyethyl (meth) acrylate, n-butoxydiethylene glycol (meth) acrylate, 2-methoxy Examples thereof include (meth) acrylates having an alkyl ether group such as ethyl (meth) acrylate and 2-ethoxyethyl (meth) acrylate; vinyls such as styrene, α-methylstyrene and vinyl acetate;
These may be used individually by 1 type, or may be used in combination of 2 or more type.

The block polymer in the present invention contains the polymer unit (B) of the ethylenically unsaturated monomer, preferably in the range of 5 to 40% by mass, more preferably 10 to 30 based on the total mass of the block polymer. Included in the range of% by mass. The range of 5 to 40% by mass is preferable because the cured product of the adhesive is excellent in breaking stress and breaking elongation.

<Polymerization initiator>
As the polymerization initiator, known azo compounds and organic peroxides can be used. These may be used individually by 1 type, or may be used in combination of 2 or more type.
The azo compound is not particularly limited, and is, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane1-cyclohexane1-). Carbonitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), 2,2'-azobis (4-methoxy) -2,4-dimethylvaleronitrile), dimethyl 1,1'-azobis (1-cyclohexanecarboxylate), dimethyl 2,2'-azobis (2-methylpropionate), 4,4'-azobis (4) -Cyanovaleric acid), 2,2'-azobis (2-hydroxymethylpropionitrile), or 2,2'-azobis [2- (2-imidazolin-2-yl) propane].
The organic peroxide is not particularly limited, and is, for example, benzoyl peroxide, t-butylperoxy2-ethylhexaate, t-butylperbenzoate, cumenehydroperoxide, diisopropylperoxydicarbonate, di-n. -Propyl peroxydicarbonate, di (2-ethoxyethyl) peroxydicarbonate, t-butylperoxyneodecanoate, t-butylperoxyviverate, (3,5,5-trimethylhexanoyl) peroxide, Examples thereof include dipropionyl peroxide and diacetyl peroxide.

The amount of the polymerization initiator used is preferably 0.001 to 15% by mass based on the total amount of the ethylenically unsaturated monomer. A range of 0.001 to 15% by mass is preferable because chain transfer polymerization effectively proceeds.

<Number average molecular weight of polymer unit (B) of ethylenically unsaturated monomer>
The number average molecular weight of the polymer unit (B) of the ethylenically unsaturated monomer is preferably in the range of 2,000 to 200,000. When it is 2,000 or more, the breaking stress of the obtained cured product is excellent, and when it is 200,000 or less, the viscosity can be easily adjusted.

<Solvent>
Reactions in the production of block polymers, such as the reaction between polyols and polyisocyanates, the reaction between urethane units and chain transfer agents, and the reaction of polymerizing ethylenically unsaturated monomers using chain transfer agent residues, are solvents. It may be carried out using. One of these solvents may be used alone, or two or more of them may be used in combination.
The solvent that may be used for the reaction between the polyol and the polyisocyanate is not particularly limited as long as it does not react with the isocyanenato group, and is, for example, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, propyl acetate, toluene, xylene. , Anisol, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, N-vinylpyrrolidone, N-methylcaprolactum, dimethyl Examples thereof include sulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethylsulfoxide, m-cresol, γ-butyrolactone and γ-valerolactone.
As the solvent that may be used for the reaction between the urethane unit and the chain transfer agent, alcohols such as ethanol, isopropanol, tertiary butanol, and diacetone alcohol can be used in addition to the above-mentioned solvent.

<Number average molecular weight of block polymer>
The number average molecular weight of the block polymer is preferably in the range of 5,000 to 300,000, more preferably in the range of 10,000 to 100,000, and even more preferably in the range of 10,000 to 50,000. Is. When it is 5,000 or more, the breaking stress of the obtained cured product is excellent, and when it is 300,000 or less, the viscosity can be easily adjusted, which is preferable.

<Manufacturing of moisture-curable adhesive>
The moisture-curable adhesive of the present invention contains a block polymer, and for the purpose of adjusting the breaking stress, flexibility, etc. of the cured adhesive, a known modified silicone resin, silanol condensation catalyst, etc., in addition to the block polymer, Silane coupling agent, phosphoric acid or phosphoric acid derivative, leveling agent or defoaming agent, filler, propellant, plasticizer, superplasticizer, wetting agent, flame retardant, viscosity modifier, preservative, stabilizer, colorant In addition, known additives such as a compound having an epoxy group, an epoxy resin, and other resins may be blended.

(Modified silicone resin)
The modified silicone resin is not particularly limited as long as it is a known resin having a crosslinkable silyl group (excluding the above block polymer), and for example, it reacts with a molecular terminal having a main chain skeleton of polyoxyalkylene or polyoxyalkylene ether. Examples thereof include resins having a sex silyl group. Examples of commercially available products of such resins include MS Polymer S810, MS Polymer S-203, Cyril SAT-115, Cyril SAT-145, Cyril SAX510, Cyril SAX520, Cyril SAX530, or Cyril SAX580 manufactured by Kaneka Corporation. Examples thereof include trade names Exester S2410, Exester W2521, or Exester A2551 manufactured by Asahi Glass Co., Ltd.

(Silanol condensing agent)
Examples of the silanol condensing agent include organic tin compounds, amine compounds, carboxylic acid metal salts, carboxylic acids, alkoxy metals, and inorganic acids.

Examples of the organotin compound include metal catalysts such as dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, and dibutyltin dimarate.

Examples of the amine compound include aliphatic amines such as octylamine, diisopropylamine, dioctylamine, trioctylamine and cyclohexylamine; pyridine, N-methylmorpholine, piperidine and 1,8-diaza-bicyclo (5,4). , 0) Undecene-7,1,5-diazabicyclo (4,3,0) Nonen-5,6-dibutylamino-1,8-diazabicyclo (5,4,0) Undecene-7,1,2-dimethyl- Nitrogen-containing heterocyclic amines such as 1,4,5,6-tetrahydropyrimidine; guanidines such as guanidine, phenylguanidine and diphenylguanidine; biguanides such as butylbiguanide, 1-o-tolylbiguanide and 1-phenylbiguanide In addition to the above, diethanolamine and triethanolamine can be mentioned.

Examples of the above-mentioned metal carboxylate salt include tin carboxylate, bismuth carboxylate, titanium carboxylate, iron carboxylate, and zirconium carboxylate.

These silanol condensing agents may be used alone or in combination of two or more. The blending amount of the silanol condensing agent is preferably 0.001 to 20% by mass based on the total mass of the moisture-curable adhesive.

(Silane coupling agent)
Examples of the silane coupling agent include trialkoxysilane having a vinyl group such as vinyltrimethoxysilane and vinyltriethoxysilane, 3-aminopropyltriethoxysilane, and N- (2-aminoethyl) 3-aminopropyltrimethoxy. Trialkoxysilane having an amino group such as silane; glycidyl group such as 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane Trialkoxysilane having; Trialkoxysilane having an isocyanato group such as 3-isocyanatopropyltriethoxysilane; Trialkoxysilane having a mercapto group such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane.
The blending amount of the silane coupling agent is preferably 0.05 to 10% by mass based on the total mass of the block polymer.

<Hardened material, laminated body>
The cured product of the present invention is obtained by curing the above-mentioned moisture-curable adhesive with moisture. The method for forming the cured product is not particularly limited, and for example, it is necessary after applying a moisture-curable adhesive having a viscosity adjusted to a viscosity suitable for the coating method using no solvent or, if necessary, a solvent or the like on the substrate. It can be obtained by, for example, heating to a temperature of 50 ° C. to 200 ° C. to remove volatile components such as a solvent, and then reacting with water at a temperature of 20 ° C. to 85 ° C. to cure.

The laminate of the present invention comprises a layer made of the above-mentioned cured product on a base material. The method for producing the laminate is not particularly limited. For example, after applying a moisture-curable adhesive on the first substrate, a volatile component such as a solvent is dried in an oven as necessary to dry an uncured resin layer. The second base material is further superposed on the resin layer, and if necessary, thermocompression bonding or the like is performed to soften and adhere the resin layer, and the resin layer can be moisture-cured for production.
Further, in the laminate of the present invention, an uncured resin layer obtained by drying a moisture-curable adhesive, which is previously molded into a sheet shape, is sandwiched between two base materials and softened by thermocompression bonding or the like to adhere to the laminate. It can be manufactured by moisture curing while allowing it to cure.
The thickness of the layer made of the cured product is appropriately selected depending on the intended use, and is preferably in the range of 0.1 μm to 300 mm.

(Base material)
The base material is not particularly limited, and is, for example, a thermoplastic polymer such as polyethylene, polylopylene, polyurethane, polyacrylate, polycarbonate, and a copolymer thereof, a thermosetting polymer such as vulture rubber, urea-formaldehyde foam, and a melamine resin. , Aluminum and other metals, wood, concrete, tiles, carbon fiber reinforced plastics, glass fiber reinforced plastics and other fiber reinforced plastics, and the substrates bonded via the adhesive may be the same. It may be different. Further, when the laminate includes two or more base materials, the plurality of base materials may be the same or different.

The moisture-curable adhesive of the present invention, the cured product and the laminate made by using the adhesive have excellent breaking stress and breaking elongation, have high followability to substrate deformation, and require long-term durability. It is useful as a bonding material and a sealing agent in the fields of automobiles, building materials, etc.

Hereinafter, the present invention will be described in more detail by way of examples, but the following examples do not limit the scope of rights of the present invention in any way. Unless otherwise specified, "parts" and "%" in the examples represent "parts by mass" and "% by mass", respectively.

<Number average molecular weight (Mn)>
For the number average molecular weight (Mn) of the resin, a conversion value using polystyrene having a known molecular weight measured by GPC (gel permeation chromatography) was used. For the measurement, GPC-8020 (manufactured by Tosoh) as a GPC device, tetrahydrofuran as an eluent, and TSKgelSuperHM-M (manufactured by Tosoh) as a column were connected in series, and the flow rate was 0.6 ml / min, the injection amount was 10 μl, and the column was used. The procedure was performed under the condition of a temperature of 40 ° C.

The abbreviations of the compounds in the present specification are shown below.
PPG3000: Polypropylene glycol (average number of functional groups: 2, number average molecular weight: 3,000)
PPG8000: Polypropylene glycol (average number of functional groups: 2, number average molecular weight: 8,000)
IPDI: Isophorone diisocyanate KBM-503: Methacrylic acid-3- (dimethoxymethylsilyl) propyl (manufactured by Shin-Etsu Chemical Co., Ltd.)
MMA: Methyl Methacrylate BMA: Butyl Methacrylate

<Manufacturing of block polymer>
(Manufacturing Example 1)
In a reaction vessel equipped with a nitrogen gas introduction pipe, a stirrer, a thermometer, and a recirculator, 100 parts of PPG3000 as a polyol, 10.4 parts of IPDI as a polyisocyanate, and 0.01 part of dibutyltin dilaurate as a catalyst were charged. After stirring uniformly, the reaction was carried out at 90 ° C. for 5 hours under a nitrogen atmosphere to obtain a urethane unit.
Next, the mixture was cooled to 60 ° C., 2.0 parts of 2-aminoethanethiol and 29.6 parts of isopropanol were added as chain transfer agents, and the mixture was reacted at 75 ° C. for 2 hours to obtain a urethane prepolymer. The end point of the reaction was confirmed by the disappearance of the peak derived from the isocyanato group ( ^{around 2270 cm -1) by FT-IR.}
Subsequently, 5.9 parts of KBM-503 as an ethylenically unsaturated monomer having a hydrolyzable silyl group was added and stirred uniformly, and then the temperature was raised to 75 ° C. under a nitrogen atmosphere, where the polymerization initiator was added. 0.2 part of 2,2'-azobis (2,4-dimethylvaleronitrile) was added in 10 portions every 30 minutes, and the reaction was carried out for another 1 hour after the addition of the polymerization initiator to remove isopropanol under reduced pressure. To obtain a block polymer.
The ratio (%) of the polymer unit (B) of the ethylenically unsaturated monomer in the obtained block polymer, and the ethylenically unsaturated unit amount having a hydrolyzable silyl group in the total ethylenically unsaturated monomer. Table 1 shows the proportion (%) of the body (b1) and the number average molecular weight of the block polymer.

(Manufacturing Examples 2 to 6)
The same operations as in Production Example 1 were carried out except that the compounds and compounding compositions shown in Table 1 were changed, to obtain block polymers of Production Examples 2 to 6, respectively. The ratio (%) of the polymer unit (B) of the ethylenically unsaturated monomer in the obtained block polymer, and the ethylenically unsaturated unit amount having a hydrolyzable silyl group in the total ethylenically unsaturated monomer. Table 1 shows the proportion (%) of the body (b1) and the number average molecular weight of the block polymer.

<Manufacturing of comparative resin>
(Comparative Manufacturing Example 1)
In a reaction vessel equipped with a nitrogen gas introduction tube, a stirrer, a thermometer, and a refluxer, 100 parts of PPG3000, 10.4 parts of IPDI as polyisocyanate, and 0.01 part of dibutyltin dilaurate as a catalyst are charged and uniformly stirred. Then, the reaction was carried out at 90 ° C. for 5 hours under a nitrogen atmosphere to obtain a urethane unit.
Next, the mixture was cooled to 60 ° C., 5.6 parts of N- (2-aminoethyl) 3-aminopropyltrimethoxysilane was added, and the mixture was reacted at 75 ° C. for 2 hours to form a urethane resin having hydrolyzable silyl groups at both ends. Got The end point of the reaction was confirmed by the disappearance of the peak derived from the isocyanato group ( ^{around 2270 cm -1) by FT-IR.} The number average molecular weight of the urethane resin was 14,000.

(Comparative Manufacturing Example 2)
In a reaction vessel equipped with a nitrogen gas introduction tube, a stirrer, a thermometer, and a recirculator, 50 parts of KBM-503, 50 parts of MMA, 7.3 parts of 2-ethylhexyl thioglycolate, and 140 parts of isopropanol were charged and stirred uniformly. After that, the temperature is raised to 75 ° C. under a nitrogen atmosphere, and one part of 2,2'-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator is added thereto in 10 portions every 30 minutes to initiate polymerization. After the addition of the agent, the reaction was carried out for another 1 hour, and isopropanol was removed under reduced pressure to obtain an acrylic resin having a hydrolyzable silyl group in the side chain. The number average molecular weight of the acrylic resin was 2,800.

<Preparation of moisture-curable adhesive>
After the block polymer obtained in Production Examples 1 to 6 and the comparative resin obtained in Comparative Production Examples 1 to 2, tin octylate, laurylamine, and water are uniformly stirred and mixed with the composition shown in Table 2. , Centrifugal defoaming was performed to prepare the moisture-curable adhesives of Examples 1 to 6 and Comparative Examples 1 to 6.

<Evaluation of moisture-curable adhesive>
The following evaluation was performed using the obtained hard-moisture-curable adhesive. The results are shown in Table 2.

[Fracture stress / elongation at break]
The prepared moisture-curable adhesive is filled in a polyethylene mold so that air bubbles do not enter, and cured at a temperature of 23 ° C. and a relative humidity of 50% for 1 hour, and further at a temperature of 50 ° C. and a relative humidity of 60% for 24 hours. A cured film having a thickness of 3 mm was prepared.
Then, it was punched out with a No. 3 dumbbell mold to prepare a dumbbell type test piece for evaluation. The obtained test piece was pulled at a tensile speed of 50 mm / min using a tensile tester under the conditions of a temperature of 23 ° C. and a relative humidity of 50%, and the breaking stress (MPa) and breaking elongation (%) were measured. Judgment was made by the standard. The larger the values of breaking stress and breaking elongation, the better, and the practical level is △ or higher.

(Evaluation criteria for breaking stress)
◯: 13 MPa or more Δ: 10 MPa or more and less than 13 MPa ×: less than 10 MPa

(Evaluation criteria for elongation at break)
○: 500% or more △: 350% or more and less than 500% ×: Less than 350%

According to the evaluation results in Table 2, the cured product of the moisture-curable adhesive of the present invention showed good breaking stress and breaking elongation. In particular, an ethylenically unsaturated monomer containing the polymer unit (B) of the ethylenically unsaturated monomer in the range of 10 to 30% by mass based on the total mass of the block polymer and having a hydrolyzable silyl group. When the body (b1) was contained in the range of 10 to 50% by mass based on the total mass of the polymer unit of the ethylenically unsaturated monomer, it was excellent in breaking stress and breaking elongation.

Claims (7)

The urethane unit (A) and the polymer unit (B) of the ethylenically unsaturated monomer contain a block polymer linked by a residue of a chain transfer agent.
A moisture-curable adhesive in which the polymer unit (B) of the ethylenically unsaturated monomer has a structural unit derived from the ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group. The moisture-curable adhesive according to claim 1, wherein the chain transfer agent is a compound having a functional group capable of reacting with an isocyanato group and a sulfanyl group. The moisture-curable adhesive according to claim 1 or 2, wherein the connecting portion between the urethane unit (A) and the residue of the chain transfer agent has a urea bond. The ethylenically unsaturated monomer constituting the polymer unit (B) of the ethylenically unsaturated monomer is a monomer of the ethylenically unsaturated monomer (b1) having a hydrolyzable silyl group. The moisture-curable adhesive according to any one of claims 1 to 3, which contains 5 to 100% by mass based on the total mass. The block polymer contains the polymer unit (B) of the ethylenically unsaturated monomer in the range of 5 to 40% by mass based on the total mass of the block polymer, according to any one of claims 1 to 4. The described moisture-curable adhesive. A cured product obtained by curing the moisture-curable adhesive according to any one of claims 1 to 5. A laminate having a layer made of the cured product according to claim 6 on a substrate.