JP2010090269A - Moisture-curable composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moisture curable composition excellent in workability, curability, producing a cured product free from foaming even under severe conditions such as high temperature and high humidity, and giving excellent rubber properties after curing. <P>SOLUTION: The moisture-curable composition for sealing materials, adhesives, pains, potting materials and the like comprises an isocyanate-containing urethane prepolymer (A) and an organic compound (B) which can regenerate an active hydrogen-containing compound by hydrolysis with moisture. The isocyanate-containing urethane prepolymer (A) contains an organic polyisocyanate monomer at a concentration of less than 1.0 mass%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention contains an isocyanate group-containing urethane prepolymer having an organic polyisocyanate monomer concentration of less than 1.0% by mass, and an organic compound capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture. The present invention relates to a moisture curable composition excellent in workability and curability.

Conventionally, sealing materials for waterproofing and sealing of buildings and civil engineering structures, resin sheets such as vinyl chloride sheets, adhesives for coated members such as tiles and wooden boards, or paint floor materials, and paints Moisture curable compositions using polyisocyanate compounds have been used as coating agents and potting materials. Moisture curable compositions using polyisocyanate compounds have excellent properties such as excellent curability, workability, rubber elastic properties of cured products over a wide range, and excellent cost performance. In addition, the applications are increasingly expanding.
The moisture curable composition using a polyisocyanate compound uses a polyisocyanate compound as a moisture curable resin component, but an organic polyisocyanate may be used as it is as a polyisocyanate compound, or it contains an active hydrogen group. It is often used as an isocyanate group-containing urethane prepolymer obtained by reacting an active hydrogen group in a compound with an excess of an isocyanate group of an organic polyisocyanate.
However, moisture curable compositions using polyisocyanate compounds are generated with curing when the isocyanate group concentration is high or when the curing rate is increased, when it reacts with moisture (humidity) in the atmosphere and cures. When the amount of carbon dioxide gas increases or when carbon dioxide gas is suddenly generated, bubbles are generated inside the cured product, so that the surface of the cured product becomes uneven or cracks occur on the surface and the appearance deteriorates ( Foaming), rubber tensile properties such as elongation of the cured product are deteriorated, and adhesiveness is deteriorated. Furthermore, if a curing accelerator is blended to improve curability (surface curability; tack-free time, internal curability), the curability is improved, but a problem that storage stability deteriorates occurs.
For this reason, in order to prevent foaming due to carbon dioxide gas, the isocyanate group-containing urethane prepolymer is particularly designed to have a low isocyanate group concentration. However, if the isocyanate group concentration is set low, foaming due to carbon dioxide gas is improved, but the increase in the high molecular weight in the isocyanate group-containing urethane prepolymer is increased, and polar groups such as urethane bonds are introduced. Although it thinks, the viscosity of an isocyanate group containing urethane prepolymer will become high, and a malfunction will arise in workability when it is set as a moisture hardening composition. In order to prevent foaming due to carbon dioxide gas, a compound that is hydrolyzed by moisture to regenerate a functional group reactive with an isocyanate group such as a primary or secondary amino group or a hydroxyl group, a so-called latent curing agent is used. It is known to use (see Patent Documents 1 and 2). However, foaming of the cured product by carbon dioxide gas can be prevented under mild conditions, but the foaming prevention effect is still insufficient under severe conditions such as summer where high temperatures and high humidity are likely to cause foaming.
In recent years, with the growing awareness of the global environment, moisture curable compositions using polyisocyanate compounds have been banned or replaced with harmful substances and organic solvents in order to reduce the burden on the global environment. Is required. If the isocyanate group concentration is designed to be low in order to improve foaming, the viscosity of the isocyanate group-containing urethane prepolymer tends to increase, and the use of an organic solvent or the like is unavoidable due to a decrease in viscosity. Designing a high isocyanate group concentration will lower the viscosity of the isocyanate group-containing urethane prepolymer, but it also means that a large amount of the organic polyisocyanate monomer remains in the isocyanate group-containing urethane prepolymer, which is not always desirable. Absent.
Even if the isocyanate group concentration is lowered, the viscosity does not increase. Therefore, it is not always necessary to use an organic solvent, and the polyisocyanate compound is excellent in curability and workability, cured without foaming and excellent in rubber physical properties. The moisture curable composition used has been sought.
JP-A-63-191820 JP 2000-212239 A

  An object of the present invention is to provide a moisture curable composition which is excellent in workability and curability, does not foam even under severe conditions of high temperature and high humidity, and has excellent rubber physical properties after curing. is there.

In order to achieve the above object, the present invention is shown in the following (1) to (9).
(1) A moisture curable composition comprising an isocyanate group-containing urethane prepolymer (A) and an organic compound (B) capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture, The moisture curable composition, wherein the isocyanate group-containing urethane prepolymer (A) is an isocyanate group-containing urethane prepolymer having an organic polyisocyanate monomer concentration of less than 1.0% by mass.
(2) After the isocyanate group-containing urethane prepolymer (A) having an organic polyisocyanate monomer concentration of less than 1.0% by mass reacts with an aliphatic diisocyanate and a polyol having a number average molecular weight of 1,000 to 50,000, The moisture-curable composition according to (1) above, which is an isocyanate group-containing urethane prepolymer in which an unreacted aliphatic diisocyanate monomer is removed by distillation so that a residual aliphatic diisocyanate monomer concentration is less than 1.0% by mass.
(3) Silicic acid capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture, wherein the organic compound (B) capable of regenerating the active hydrogen group-containing compound by hydrolysis with moisture The moisture-curable composition according to the above (1) or (2), which is an ester compound.
(4) The moisture-curable composition according to (3), wherein the silicate compound is a silicate compound obtained by a dealcoholization reaction between the polyol (b1) and the alkoxysilyl group-containing compound (b2).
(5) The moisture-curable composition according to any one of (1) to (4), further comprising a curing accelerator (C).
(6) The moisture-curable composition according to (5), wherein the curing accelerator (C) is a tin-based curing accelerator.
(7) The moisture-curable composition according to (6), wherein the tin-based curing accelerator is an organic tin compound and a tin chelate compound.
(8) Further, from fillers, plasticizers, weathering stabilizers, thixotropic agents, adhesion promoters, storage stability improvers (dehydrating agents), oxygen curable compounds, design enhancers, solvents and colorants. The moisture-curable composition according to any one of (1) to (7), wherein one or more additives selected from the group consisting of the above are blended.
(9) A moisture curable sealing material composition comprising an isocyanate group-containing urethane prepolymer (A) and an organic compound (B) capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture. The moisture curable sealant composition is characterized in that the isocyanate group-containing urethane prepolymer (A) is an isocyanate group-containing urethane prepolymer having an organic polyisocyanate monomer concentration of less than 1.0% by mass.

  For the first time according to the present invention, sealing materials, adhesives, paints, potting materials, etc. that are excellent in workability and curability, do not foam even under severe conditions of high temperature and humidity, and have excellent rubber properties after curing. It became possible to provide a moisture-curable composition with a wide range.

The present invention will be described in detail below.
The isocyanate group-containing urethane prepolymer (A) in the present invention is an isocyanate group-containing urethane prepolymer having an organic polyisocyanate monomer concentration of less than 1.0% by mass, and the isocyanate group reacts with moisture (moisture) to form a urea bond. It is formed, crosslinked and cured. Specifically, after the reaction between the organic polyisocyanate and the active hydrogen group-containing compound, unreacted remaining organic polyisocyanate monomer (or unreacted remaining organic polyisocyanate monomer and organic solvent) is thin-film distilled. By doing so, it is removed from the isocyanate group-containing urethane prepolymer, and the concentration of the remaining organic polyisocyanate monomer present in the isocyanate group-containing urethane prepolymer is less than 1.0% by mass.
More specifically, the organic polyisocyanate and the active hydrogen group-containing compound have an equivalent ratio of isocyanate group / active hydrogen (group) of the total raw materials of 2.0 or more / 1.0, more preferably 2.0-15. It can be suitably produced by reacting simultaneously or sequentially within a range of 0 / 1.0. If the equivalent ratio is less than 2.0, an isocyanate group-containing urethane prepolymer cannot be obtained, or a urethane prepolymer can be obtained, but the viscosity becomes high and subsequent thin film distillation becomes difficult. It is not economical because of the high setting of time, the time required for distillation or the number of distillations increases, and the urethane prepolymer obtained has too few cross-linking points, and the moisture curable composition after curing Elongation, tensile strength, etc. are lowered, and rubber elastic properties and adhesiveness are poor, which is not preferable. When the equivalence ratio is increased, it is convenient to obtain a decrease in viscosity due to a decrease in the content of the high molecular weight in the isocyanate group-containing urethane prepolymer, but on the other hand, the amount of organic polyisocyanate monomer removed by thin film distillation is large. It is not economically preferable. The thus obtained isocyanate group-containing urethane prepolymer (A) having an unreacted organic polyisocyanate monomer concentration of less than 1.0 mass% by distillation is active with the same organic polyisocyanate and the same active hydrogen group-containing compound. Compared to an isocyanate group-containing urethane prepolymer that is obtained by reacting an isocyanate group with an excess of a hydroxyl group and does not perform thin-film distillation, the viscosity is low despite the low isocyanate concentration, and therefore the moisture curable composition In this case, the workability is excellent and the foaming resistance is good. Surprisingly, the isocyanate group-containing urethane prepolymer (A) having an unreacted organic polyisocyanate monomer concentration of less than 1.0 mass% by distillation, and the active hydrogen group-containing compound are regenerated by hydrolysis with moisture. The moisture-curable composition containing the organic compound (B) capable of being cured and the curing accelerator (C) is characterized by having excellent internal curability without increasing the tack-free time. It has an effect.

Examples of the active hydrogen group-containing compound include polymeric polyols, amino alcohols, and polyamines.
Examples of the polymer polyol include polyoxyalkylene polyols, polyester polyols, polyester amide polyols, polyether / ester polyols, polycarbonate polyols, poly (meth) acrylic polyols, hydrocarbon polyols, and the like. A polyol having a number average molecular weight of 1,000 to 50,000, preferably 000 or more.
Examples of the polyoxyalkylene-based polyol include those obtained by ring-opening addition polymerization of alkylene oxide, and those obtained by ring-opening addition polymerization of alkylene oxide in an initiator such as a compound containing two or more active hydrogens.
Examples of the initiator include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, pentaerythritol, diglycerin and the like. Low molecular weight polyhydric alcohols, sorbitol, sucrose, glucose, lactose, low molecular weight polyhydric alcohols such as glucose, lactose, sorbitan, low molecular weight polyphenols such as bisphenol A and bisphenol F, low molecular weight such as ethylenediamine and butylenediamine Polyamines, low molecular amino alcohols such as monoethanolamine and diethanolamine, low molecular polycarboxylic acids such as adipic acid and terephthalic acid, and at least one of these is alkylene oxide Polyoxyalkylene polyol having a low molecular weight obtained by reacting the like.
Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran and the like, and these can be subjected to ring-opening addition polymerization alone or in combination of two or more.
Specifically, polyoxyalkylene polyols are specifically polyoxyethylene polyol, polyoxypropylene polyol, polytetramethylene ether polyol, poly (oxyethylene) -poly (oxypropylene) -random or block copolymer polyol, poly (Oxypropylene) -poly (oxybutylene) -random or block copolymer polyols and the like, and these various polyols and organic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. There may also be mentioned those having a hydroxyl group at the molecular end by reacting with an isocyanate group in excess of the hydroxyl group.
The polyoxyalkylene-based polyol preferably has a number average molecular weight of 1,000 to 50,000, more preferably 1,000 to 30,000, and particularly preferably 1,000 to 20,000 for reasons such as good workability. Moreover, the average number of alcoholic hydroxyl groups per molecule is 2 or more, more preferably 2 to 4, and most preferably 2 to 3. Among these, since the viscosity of the isocyanate group-containing urethane prepolymer obtained is low and the physical properties after curing are good, the viscosity of the moisture curable composition obtained therefrom is low and the workability is good, and the rubber after curing From the viewpoint of high elastic properties and adhesiveness, polymer polyols are preferred, polyoxyalkylene polyols are more preferred, polyoxypropylene polyols are particularly preferred, and polyoxypropylene triols are most preferred. In addition, high molecular monoalcohols such as polyoxyalkylene monoalcohol, butyl alcohol, and octadecyl monoalcohol, and low molecular monoalcohols can be used for modifying the isocyanate group-containing urethane prepolymer.
Further, the polyoxyalkylene-based polyol is obtained by using a catalyst such as a double metal cyanide complex, and has a total unsaturation of 0.1 meq / g or less, further 0.07 meq / g or less, particularly 0.04 meq / g. The following are preferable, and the molecular weight distribution [ratio of polystyrene-equivalent weight average molecular weight (Mw) to number average molecular weight (Mn) by gel permeation chromatography (GPC) = Mw / Mn]] is 1.6 or less, particularly 1 A narrow one of 0.0 to 1.3 is preferable.
In the present invention, the polyoxyalkylene-based polyol is composed of 50% by mass or more, more preferably 80% by mass or more, particularly preferably 90% by mass or more of the portion excluding 1 mol of hydroxyl group in the molecule. Means that the remaining part may be modified with ether, urethane, ester, polycarbonate, polyamide, polyacrylate, polyolefin, etc., but in the present invention, 95% by mass or more of the molecule excluding the hydroxyl group. Most preferred is a polyol consisting of polyoxyalkylene.
Examples of polyester polyols and polyester amide polyols include, for example, known dicarboxylic acids such as succinic acid, adipic acid, and terephthalic acid, their acid esters, acid anhydrides, and the like, and initiators for the synthesis of the above polyoxyalkylene polyols. Examples thereof include compounds obtained by a dehydration condensation reaction with a compound containing two or more active hydrogens to be used. Further examples include lactone polyester polyols obtained by cleavage polymerization of cyclic ester (ie, lactone) monomers such as ε-caprolactone.
Examples of the polyether ester polyol include compounds produced from the polyoxyalkylene polyol and the dicarboxylic acid, acid anhydride and the like.
Examples of the polycarbonate polyol include a dehydrochlorination reaction between low molecular polyhydric alcohols used in the production of the polyoxyalkylene polyol and phosgene, or transesterification with diethylene carbonate, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, and the like. The compound obtained from reaction etc. is mentioned.
Examples of the poly (meth) acrylic polyol include those obtained by copolymerizing a hydroxyethyl (meth) acrylate containing a hydroxyl group with another (meth) acrylic acid alkyl ester monomer.
Examples of the hydrocarbon polyol include polybutadiene polyol, hydrogenated polybutadiene polyol, polyisoprene polyol, hydrogenated polyisoprene polyol, chlorinated polyethylene polyol, and chlorinated polypropylene polyol.
Examples of the polyol further include low molecular weight polyhydric alcohols having a number average molecular weight of less than 500, which are listed as raw materials for producing the polyoxyalkylene polyol.
Examples of the polyamine include high-molecular polyamines such as polyoxyalkylene polyamines having a number average molecular weight of 500 or more and a polyoxyalkylene polyol terminal having an amino group, such as a terminal diaminated product of polypropylene glycol.
Examples of the polyamine further include low molecular weight polyamines having a number average molecular weight of less than 500, such as ethylenediamine, hexamethylenediamine, isophoronediamine, diaminodiphenylmethane, and diethylenetriamine.
Examples of amino alcohols include monoethanolamine, diethanolamine, N-methyldiethanolamine, N-methyldipropanolamine, and N-phenyldiethanolamine.
In addition, polyamide resins, polyester resins and the like having a number average molecular weight of 500 or more, which generally contain active hydrogen groups known in the polyurethane industry, are also included.
Any of these may be used alone or in combination of two or more.
Among these, since the viscosity of the isocyanate group-containing urethane prepolymer obtained is low and the physical properties after curing are good, the viscosity of the moisture curable composition obtained therefrom is low and the workability is good, and the rubber after curing From the viewpoint of high elastic properties and adhesiveness, polymer polyols are preferable, polyoxyalkylene polyols are more preferable, and polyoxypropylene polyols are particularly preferable.
For the modification of the isocyanate group-containing urethane prepolymer, a high molecular monoalcohol such as polyoxyalkylene monoalcohol, butyl alcohol, octadecyl monoalcohol, or a low molecular monoalcohol can be used.

The organic polyisocyanate is a compound containing two or more isocyanate groups in the molecule. Specifically, for example, toluene diisocyanates such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, 4,4 ′ -Diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, diphenylmethane diisocyanate such as 2,2'-diphenylmethane diisocyanate, phenylene diisocyanate such as 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, 1,4-naphthalene diisocyanate Naphthalene diisocyanates such as 1,5-naphthalene diisocyanate, chlorophenylene-2,4-diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 3,3'- Aromatic polyisocyanates such as dimethoxydiphenyl-4,4'-diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2, Aliphatic polyisocyanates such as 4,4-trimethyl-1,6-hexamethylene diisocyanate, decamethylene diisocyanate, lysine diisocyanate, o-xylylene diisocyanate, m-xylylene diisocyanate And cycloaliphatic polyisocyanates such as xylylene diisocyanates such as p-xylylene diisocyanate, 1,4-cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Group polyisocyanates. Furthermore, organic polyisocyanates such as polymethylene polyphenyl polyisocyanate and crude toluene diisocyanate can also be used.
In addition, modified isocyanates containing one or more uretdione bonds, isocyanurate bonds, allophanate bonds, burette bonds, uretonimine bonds, carbodiimide bonds, urethane bonds, urea bonds and the like obtained by modifying these organic polyisocyanates can also be used.
Of the aromatic polyisocyanates, toluene diisocyanates, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, 3,3'- A compound such as dimethyldiphenylmethane-4,4′-diisocyanate is classified as an aromatic polyisocyanate having a steric hindrance having a steric hindrance group such as a methyl group or an ethyl group in the aromatic ring in the vicinity of the isocyanate group.
These can be used alone or in combination of two or more.
Among these, aromatic polyisocyanates having steric hindrance, araliphatic polyisocyanates, in terms of the low viscosity of the resulting isocyanate group-containing urethane prepolymer and the slow reaction rate between the isocyanate groups of the urethane prepolymer and moisture, Aliphatic polyisocyanates and alicyclic polyisocyanates are preferred, and in terms of good weather resistance, aromatic aliphatic polyisocyanates, aliphatic polyisocyanates and alicyclic polyisocyanates are preferred, and aliphatic diisocyanates are particularly preferred. Hexamethylene diisocyanate is most preferred because of its industrial availability.

When synthesizing an isocyanate group-containing urethane prepolymer, a metal such as zinc, tin, zirconium, bismuth, cobalt, manganese, iron and the like and an organic acid such as octyl acid and naphthenic acid, such as tin octylate and zirconium octylate, Organic metal chelate compounds such as dibutyltin diacetylacetonate, zirconium tetraacetylacetonate, titanium tetraacetylacetonate, EXCESTAR C-501 (manufactured by Asahi Glass Co., Ltd.), and organic metals such as dibutyltin dilaurate and dioctyltin dilaurate Known urethanization catalysts such as organic metal compounds such as salts with acids, organic amines such as triethylenediamine, triethylamine and tri-n-butylamine, and salts thereof can be used. Of these, organometallic compounds are preferred, and dibutyltin dilaurate is more preferred.
Furthermore, an organic solvent not containing an active hydrogen group reactive with a known isocyanate group can also be used.

  The isocyanate group content of the isocyanate group-containing urethane prepolymer (A) is preferably 0.2 to 15.0% by mass, more preferably 0.5 to 10.0% by mass, and particularly preferably 0.5 to 5.0% by mass. Is preferred. When the isocyanate group content is less than 0.2% by mass, there are few crosslinking points in the prepolymer, so that sufficient adhesiveness cannot be obtained. When the isocyanate group content exceeds 15.0% by mass, the number of crosslinking points in the prepolymer increases and the rubber elasticity deteriorates, and the amount of carbon dioxide generated by the reaction with moisture increases and the cured product foams. It is not preferable in terms.

  The isocyanate group-containing urethane prepolymer (A) is used as a one-component moisture curable type by reacting and curing with moisture (humidity) in the atmosphere at room temperature.

In the present invention, the organic compound (B) capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture is blended with the isocyanate group-containing urethane prepolymer (A) to thereby convert the isocyanate group with moisture. Even if the reaction rate is slow, the active hydrogen groups generated by reacting with moisture should be fast so that the reaction rate with isocyanate groups is high, and should be less than the equivalent ratio of isocyanate groups in the urethane prepolymer. As a result, the curing rate of the moisture curable composition can be increased, and foaming due to carbon dioxide gas can be suppressed to obtain a cured product having good rubber elastic properties. It is assumed that the isocyanate groups remaining in a small amount remain on the surface of the cured product for a relatively long time due to the slow reaction rate with moisture. However, after curing, the surface of the cured product is overcoated in a relatively short period of time. It has the effect of increasing the adhesion of the paint when it is applied.
Specific examples of the organic compound (B) capable of regenerating an active hydrogen group-containing compound by hydrolysis by moisture include ketimine compounds and aldimines having a primary and / or secondary amino group. A compound, an oxazolidine compound, a silicate compound, or a mixture of any two or more thereof can be exemplified. Of these, the moisture-curable composition has excellent storage stability, and there is no generation of harmful substances such as aldehydes and there is less impact on the environment. Silicate ester compounds that can be used are preferred.
Ketimine compounds are obtained by dehydration reaction between a compound having a primary amino group and ketones, aldimine compounds are obtained by dehydration reaction between a compound having a primary amino group and aldehydes, and oxazolidine compounds are produced by monoethanolamine or diethanolamine. It can be obtained by a dehydration reaction between an amino alcohol having a primary amino group or a secondary amino group and an aldehyde.
Depending on the raw material selected, active hydrogen groups such as secondary amino groups and hydroxyl groups may remain in the molecule of the compound obtained by the above dehydration reaction. Moisture with excellent storage stability that does not react in the absence of moisture even if it coexists with an isocyanate group-containing urethane prepolymer by reacting with an isocyanate group of polyisocyanate or a carboxyl group of an organic carboxylic acid compound and blocking it. A curable composition can be made.
Further, as the oxazolidine compound, the hydroxyl group remaining in the molecule of the compound having an oxazolidine group obtained by the dehydration reaction of diethanolamine and isobutyraldehyde mentioned below is urethanated with the isocyanate group of the organic polyisocyanate mentioned above. The urethane group-containing oxazolidine compound obtained is particularly preferred. In this case, the organic polyisocyanate used is preferably an aliphatic polyisocyanate, particularly hexamethylene diisocyanate, from the viewpoint that the viscosity of the resulting urethane group-containing oxazolidine compound is low.
The silicic acid ester compound is obtained by substituting the alkoxysilyl group-containing compound (silicic acid ester of monohydric alcohol) (b2) with polyol (b1) and distilling off the produced monohydric alcohol, or by halogenating silicic acid. It can be obtained by dehydrohalogenating a compound and a polyol. Among these, a silicate compound obtained by demonohydric alcohol reaction between the polyol (b1) and the alkoxysilyl group-containing compound (b2) is preferable from the viewpoint of ease of production.
Any of these may be used alone or in combination of two or more.

Examples of the compound having a primary and / or secondary amino group include polyamine, polyaminosilane, amino alcohol and the like, and these can be used alone or in admixture of two or more.
Examples of the polyamine include ethylenediamine, phenylenediamine, diethylenetriamine, triethylenetetramine, methylaminopropylamine, and 3,3′-diaminodipropylamine.
Examples of the polyaminosilane include N-β-aminoethyl-γ-aminopropyltrimethoxysilane and N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane.
Examples of amino alcohols include monoethanolamine and diethanolamine.

Examples of the ketones include methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 4-methyl-2-pentanone, 2-heptanone, 4-heptanone, diisopropyl ketone, diisobutyl. Aliphatic ketones such as ketones, aromatic ketones such as propiophenone and benzophenone, cyclic ketones such as cyclopentanone, cyclohexanone and methylcyclohexanone, β-dicarbonyl compounds such as ethyl acetoacetate, or any of these The mixture of 2 or more types is mentioned.
Examples of the aldehydes include propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-pentylaldehyde, 2-methylbutyraldehyde, n-hexylaldehyde, 2-methylpentanal, n-heptylaldehyde, and n-octylaldehyde. , Benzaldehyde, cuminaldehyde, or a mixture of any two or more thereof.

  Examples of the alkoxysilyl group-containing compound (b2) used in the production of the silicate compound include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane, monoalkyltrisilanes such as methyltrimethoxysilane and methyltriethoxysilane. Dialkyldialkoxysilanes such as alkoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trialkylmonoalkoxysilanes such as trimethylmonomethoxysilane, trimethylmonoethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxy Examples include alkoxysilane coupling agents such as propylmethyldiethoxysilane. These can be used alone or in admixture of two or more.

The polyol (b1) used for the production of the silicate compound may be a compound containing two or more hydroxyl groups in the molecule, such as ethylene glycol, 1,4-butanediol, diethylene glycol, neopentyl glycol. 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, trimethylolpropane, pentaerythritol, polyoxyethylene glycol, polyoxytetramethylene glycol And polyols consisting of primary and secondary hydroxyl groups such as propylene glycol, 1,3-butanediol, 1,4-pentanediol, glycerin and polyoxypropylene glycol. These can be used alone or in admixture of two or more.
Of these, polyols composed only of primary hydroxyl groups are preferred, and silicate compounds produced by neopentyl glycol are particularly preferred because of their low viscosity.
When synthesizing the silicate compound by transesterification of the dialkyl dialkoxylane, monoalkyltrialkoxysilane, or tetraalkoxysilane and polyol, it is possible to leave a part of the raw material alkoxysilane. However, in this case, the monohydric alcohol generated by hydrolysis reacts with the isocyanate group-terminated urethane prepolymer to hinder cross-linking polymerization. In order to suppress this side reaction, a secondary or tertiary monohydric alcohol is added to the remaining alkoxysilane, alcoholysis is performed, and a primary alcohol such as methanol or ethanol is distilled out of the system. And a silicate compound comprising a secondary or tertiary monohydric alcohol. This silicate compound generates a polyol and a secondary or tertiary monohydric alcohol by hydrolysis, but the secondary or tertiary monohydric alcohol reacts slowly with an isocyanate group, so that a primary such as ethylene glycol is used. The isocyanate group-terminated urethane prepolymer is polymerized preferentially by the reaction between the polyol and the isocyanate group, and the secondary or tertiary monohydric alcohol evaporates out of the system without being reacted.
Examples of the secondary or tertiary monohydric alcohol include 1 such as isopropanol, sec-butanol, 2-octanol, tert-butanol, tert-octanol and 2,3,4-trimethyl-1,3-pentadiol monobutyrate. And monohydric alcohols.

  Examples of the halogen compound of silicic acid include tetrachlorosilane, alkyltrichlorosilane, dialkyldichlorosilane, and trialkylmonochlorosilane. These can be used alone or in admixture of two or more.

  Examples of the silicate compound include cyclic silicate compounds in addition to chain esters. Specifically, for example, as dialkoxysilane, dimethyl / ethylenedioxysilane dimer, dimethyl (trimethylene-1,3-dioxy) silane, dimethyl (tetramethylene-1,4-dioxy) silane, dimethyl (2 , 2'-oxydiethoxy) silane, dimethyl (2,2'-ethylenedioxydiethoxy) silane, tetramethyl-1,3- (2,2'-oxydiethoxy) disiloxane, and tri Examples of alkoxysilanes include viscous liquid products obtained by condensing two molecules of methyltrimethoxysilane, two molecules of 3-glycidoxypropyltrimethoxysilane, and three molecules of neopentyl glycol.

In the present invention, the mixing ratio between the isocyanate group-terminated urethane prepolymer (A) and the organic compound (B) capable of regenerating the active hydrogen group-containing compound by hydrolysis with moisture is the ratio of the organic compound (B). The active hydrogen group regenerated by hydrolysis is 0.1 to 1.2 equivalents, and further 0.3 to 1.0 equivalents per equivalent of the terminal isocyanate group in the urethane prepolymer (A). Is preferred. If the regenerated active hydrogen group is less than 0.1 equivalent, excess isocyanate group reacts with moisture to cause foaming. Conversely, if it is more than 1.2 equivalent, the molecular end stops at the active hydrogen group and polymerizes. This is not preferable because it cannot be performed and the tackiness is poor and the adhesiveness after curing is also poor.
In the present invention, the reaction between the organic compound (B) that can be hydrolyzed by moisture to regenerate the active hydrogen group-containing compound and moisture in the air and the reaction between the isocyanate group and the active hydrogen group are the isocyanate group and moisture. It is much faster than the reaction. Therefore, when the moisture curable composition comes into contact with moisture, the hydrolysis of the organic compound (B) takes precedence over the reaction between the isocyanate group and moisture, and then the reaction between the regenerated active hydrogen group and the isocyanate group occurs. As a result, foaming and swelling of the cured product by carbon dioxide gas are prevented.

  The organic compound (B) that can be hydrolyzed by moisture to regenerate the active hydrogen group-containing compound is 0.1 to 50 parts by weight, particularly 1 to 100 parts by weight of the isocyanate group-containing urethane prepolymer (A). It is preferable to use ~ 20 mass parts.

The curing accelerator (C) in the present invention is a catalyst for accelerating the curing of the isocyanate group-containing urethane prepolymer (A). Specific examples include organometallic compounds, amines, and the like, for example, divalent organotin compounds such as tin octylate, tin octenoate and tin naphthenate, dibutyltin dioctoate, dibutyltin dilaurate, and dibutyltin diacetate. Tetravalent organotin compounds such as dibutyltin dimaleate, dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversate, dibutyltin oxide, dibutyltin bis (triethoxysilicate), a reaction product of dibutyltin oxide and phthalate, Dibutyltin bis (acetylacetonate), tin chelate compound EXCESTAR C-501 manufactured by Asahi Glass Co., Ltd., zirconium tetrakis (acetylacetonate), titanium tetrakis (acetylacetonate), aluminum tris (acetylacetonate) , Aluminum tris (ethyl acetoacetate), acetylacetone cobalt, acetylacetone iron, acetylacetone copper, acetylacetone magnesium, acetylacetone bismuth, acetylacetone nickel, acetylacetone zinc, acetylacetone manganese and other metal chelate compounds, organic acid lead salts such as lead octylate, Titanates such as tetra-n-butyl titanate and tetrapropyl titanate, organic bismuth compounds such as bismuth octylate and bismuth versatate, triethylamine, tributylamine, triethylenediamine, hexamethylenetetramine, 1,8-diazabicyclo [5, 4,0] undecene-7 (DBU), 1,4-diazabicyclo [2,2,2] octane (DABCO), N-methylmorpholine Tertiary amines such as N- ethylmorpholine, or a salt such as these amines and carboxylic acids. Of these, tin-based curing accelerators such as organotin compounds and tin chelate compounds are preferred because of their high reaction rate and relatively low toxicity and volatility, and in particular tin octenoate and dibutyltin bis (acetylacetate). Naruto) is preferred.
These can be used alone or in combination of two or more.
A hardening accelerator (C) is 0.001-10 mass parts with respect to 100 mass parts of isocyanate group containing urethane prepolymer (A) from points, such as a cure rate and the physical property of hardened | cured material, Especially 0.01-2 mass. It is preferable to blend partly.

As additives in the present invention, fillers, plasticizers, weathering stabilizers, thixotropic agents, adhesion promoters, storage stability improvers (dehydrating agents), oxygen curable compounds, designability promoters, solvents, One or more kinds such as a colorant are preferably exemplified.
Filler, thixotropic agent, adhesion-imparting agent, storage stability improver (dehydrating agent), designability-imparting agent, and coloring agent are reinforced and increased, thixotropic improvement, adhesion improvement, storage stability improvement, It is used for providing a design property such as matting of the surface of the cured product, imparting irregularities (providing roughness), coloring, and the like.

  Examples of the filler include mica, kaolin, zeolite, graphite, diatomaceous earth, white clay, clay, talc, slate powder, anhydrous silicic acid, quartz fine powder, aluminum powder, zinc powder, and synthetic silica such as precipitated silica, heavy Inorganic fillers such as calcium carbonate, light calcium carbonate, magnesium carbonate, alumina, calcium oxide, magnesium oxide, inorganic fillers such as asbestos, glass fibers, carbon fibers, etc., or their surface Fillers treated with organic substances such as fatty acids, wood flour, walnut flour, rice husk flour, pulp powder, cotton chips, rubber powder, as well as polyamide resin, polyester resin, polyurethane resin, silicone resin, vinyl chloride resin, vinyl acetate resin, Polyolefin resins such as polyethylene and polypropylene, acrylic resins, In addition to organic fillers such as thermoplastic resin such as poxy resin, phenol resin, urea resin, melamine resin, or thermosetting resin powder, flame retardant filler such as magnesium hydroxide and aluminum hydroxide And a particle size of 0.01 to 1,000 μm is preferable.

Examples of the plasticizer include phthalates such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, di (2-ethylhexyl) phthalate, butyl benzyl phthalate, butyl phthalyl butyl glycolate, dioctyl adipate, dioctyl sebacate and the like. Low molecular weight plasticizers having a molecular weight of less than 500, such as non-aromatic dibasic acid esters, phosphate esters such as tricresyl phosphate and tributyl phosphate, and halogenated aliphatic compounds such as chlorinated paraffin, etc., and a molecular weight of 500 or more Examples of the high molecular weight type plasticizer include polyester plasticizers such as polyesters from dicarboxylic acids and glycols, etherified or esterified derivatives of polyethylene glycol and polypropylene glycol, Polyethers such as sugar-based polyethers obtained by addition polymerization of ethylene oxide or propylene oxide to saccharide polyhydric alcohols such as rose, and etherification or esterification, polystyrenes such as poly-α-methylstyrene, and low viscosity Examples include (meth) acrylic acid ester copolymers.
Among these, a high molecular weight type plasticizer having a molecular weight of 500 or more is preferable in that it hardly migrates (bleeds) to the surface of the cured product.

  The weathering stabilizer is used to prevent oxidation, photodegradation, and thermal degradation after curing of the isocyanate group-containing urethane prepolymer and further improve not only the weather resistance but also the heat resistance. Specific examples of the weather resistance stabilizer include an antioxidant, an ultraviolet absorber, and a photocurable compound.

Specific examples of the antioxidant include hindered amine-based and hindered phenol-based antioxidants. Examples of the hindered amine-based antioxidant include bis (1,2,2,6,6-pentamethyl). -4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] butyl malonate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) Examples include sebacate, methyl-1,2,2,6,6-pentamethyl-4-piperidyl sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine. In addition to Sanyo LS-292, trade names manufactured by Sankyo Co., Ltd., trade names Adeka Stub series LA-52, LA-57, LA-62, LA-67, LA-77, LA- 82, LA-87 and other low molecular weight hindered amine antioxidants with a molecular weight of less than 1,000, also LA-63P, LA-68LD or Ciba Specialty Chemicals' product names CHIMASSORB series 119FL, 2020FDL, 944FD, 944LD And high molecular weight hindered amine antioxidants having a molecular weight of 1,000 or more.
Examples of the hindered phenol antioxidant include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-). tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide)], benzenepropanoic acid Examples include 3,5-bis (1,1-dimethylethyl) -4-hydroxy C7-C9 side chain alkyl ester, 2,4-dimethyl-6- (1-methylpentadecyl) phenol, and the like.

  Examples of the ultraviolet absorber include benzotriazole-based ultraviolet absorbers such as 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, and 2- (4,6-diphenyl- Triazine-based UV absorbers such as 1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, benzophenone-based UV absorbers such as octabenzone, 2,4-di-tert-butylphenyl Examples include benzoate-based ultraviolet absorbers such as -3,5-di-tert-butyl-4-hydroxybenzoate.

  Examples of the photocurable compound include a compound containing one or more groups that are reactively cured by light such as an acryloyl group or a methacryloyl group in the molecule. Polyester acrylate or polyester methacrylate such as urethane acrylate, urethane methacrylate, ester acrylate or ester methacrylate such as trimethylolpropane triacrylate or trimethylolpropane trimethacrylate, acrylate or methacrylate of polyethylene adipate polyol, etc. Polyether acrylate such as ether polyol acrylate or methacrylate, polyether methacrylate, or poly Examples thereof include vinyl cinnamates and azido resins, and monomers and oligomers having a molecular weight of 10,000 or less, and more preferably a molecular weight of 5,000 or less are preferred. The thing containing 2 or more is preferable.

  Examples of the thixotropic agent include inorganic thixotropic agents such as colloidal silica, asbestos powder, and fatty acid-treated calcium carbonate, and organic thixotropic agents such as organic bentonite, modified polyester polyol, and fatty acid amide.

Examples of the adhesion imparting agent include a coupling agent, an epoxy resin, a phenol resin, an alkyd resin, an alkyl titanate, and an organic polyisocyanate.
Examples of the coupling agent include various coupling agents such as silane, aluminum and zircoaluminate and / or partial hydrolysis condensates thereof. Of these, a silane coupling agent and / or a partially hydrolyzed condensate thereof is preferred because of its excellent adhesiveness.
As silane coupling agents, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, n-propyltrimethoxysilane, ethyltrimethoxysilane, diethyldiethoxysilane, n-butyltrimethoxysilane, n-hexyltriethoxysilane , N-octyltrimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, cyclohexylmethyldimethoxysilane and other hydrocarbon group-bonded alkoxysilanes, dimethyldiisopropenoxysilane, methyltriisopropenoxysilane and other hydrocarbon group-bonded Isopropenoxysilanes, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyldimethylmeth Sisilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-glycidoxypropylmethyl Diisopropenoxysilane, 3-glycidoxypropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane , 3-acryloxypropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and other functional groups such as alkoxysilanes and isopropenoxysilanes having a molecular weight of 500 or less, preferably 400 or less. Compounds having a molecular weight 200 to 3,000 are exemplified in compound and / or one or more partially hydrolyzed condensate of the silane coupling agent.

  Examples of the storage stability improver include low-molecular crosslinkable silyl group-containing compounds such as vinyltrimethoxysilane, calcium oxide, and p-toluenesulfonyl isocyanate that react with moisture present in the moisture-curable composition. It is done.

An oxygen curable compound is a compound having in its molecule an unsaturated group that reacts and cures with oxygen, such as in the air, and is incorporated into the isocyanate group-containing urethane prepolymer (A) to thereby form a moisture curable composition. It is surmised that it is due to the formation of a cured film by moving to the surface after curing, but in order to eliminate the adhesion of the surface of the cured product, it exhibits a long-term surface contamination prevention effect, and surprisingly, after curing After a long period of time, even if the cured product surface is coated with a paint, it has an effect that the adhesion of the coating film becomes good. Furthermore, it also has the effect of improving the water-resistant adhesion of the coating film.
Specifically, drying oils, various modified products of drying oils, liquid polymers and copolymers of diene compounds, various modified products of these (co) polymers (maleinized modified products, boiled oil modified products, etc.) And a mixture thereof, among which dry oil and various modified products thereof, particularly dry oil are preferred.
Examples of drying oils (including semi-drying oils in a broad sense) include paulownia oil, soybean oil, linseed oil, dehydrated castor oil, coconut oil, castor oil, and the like. And various alkyd resins obtained, acrylic polymers modified with drying oil, epoxy resins, silicone resins, and the like.
Examples of (co) polymers of diene compounds include polymers of C _{4 to} C ₈ diene compounds such as 1,2-butadiene, 1,4-butadiene, 1,3-pentadiene, isoprene, chloroprene, and the like. Examples of the above-mentioned copolymers, or copolymers of these with other monomers such as styrene and acrylonitrile (SBR, NBR, etc.) and the like, and modified products of (co) polymers of diene compounds, Examples thereof include maleated products, boiled products, and epoxidized products of (co) polymers of the diene compounds.

Designability-imparting agents can be added to moisture-curable compositions to assist in delustering the surface of the cured product, or to provide an appearance that mimics the rough texture of rocks. In particular, examples of those that impart matte properties include matt waxes, various waxes such as beeswax, carnauba wax, montan wax, paraffin wax, and stearic acid. And higher aliphatic compounds such as amides.
Examples of the material that removes the gloss of the surface and imparts irregularities include granular materials and balloons, etc. The granular materials are the same as those mentioned as the filler, and large particles having a particle size of 50 μm or more are mentioned. It is done.
The balloon is a hollow substance, and the shape is not only spherical, but also various shapes such as a cubic shape, a rectangular shape, and a confetti shape, and the balloon is slightly broken to such an extent that the effect of imparting unevenness to the moisture curable composition is not lost. Although it is mentioned, a spherical shape is preferable from the viewpoint of good workability of the moisture curable composition. Specifically, for example, inorganic balloons such as glass balloons, shirasu balloons, silica balloons, ceramic balloons, organic balloons such as phenol resin balloons, urea resin balloons, polystyrene balloons, polyethylene balloons, saran balloons, or inorganic compounds and organic Examples thereof include a composite balloon in which a system compound is mixed or laminated.
Also, those coated or surface-treated with these balloons can be used. For example, inorganic balloons surface-treated with the silane coupling agent, etc., organic balloons with calcium carbonate, talc, titanium oxide, etc. Examples of coatings are also included.
Of these, from the viewpoint of the effect of imparting designability, granular materials and / or balloons are preferable, and granular inorganic fillers and / or inorganic balloons are more preferable, especially coarse heavy calcium carbonate and / or ceramics. A balloon is preferred.
The particle size of the granular material and / or balloon is preferably 50 μm or more, and more preferably 100 to 1,000 μm, from the viewpoint of the effect of providing designability.

  Examples of the solvent include conventionally known organic solvents such as an aliphatic solvent such as n-hexane, an alicyclic solvent such as cyclohexane, and an aromatic solvent such as toluene and xylene. Any substance that does not react with each component can be used.

  Examples of the colorant include inorganic pigments such as titanium oxide and iron oxide, organic pigments such as copper phthalocyanine, and carbon black.

  The total compounding amount of the additives is preferably 0 to 500 parts by mass, particularly 10 to 300 parts by mass with respect to 100 parts by mass of the isocyanate group-containing urethane prepolymer (A).

  In the present invention, each additive component can be used alone or in combination of two or more.

The present invention will be described in more detail with reference to the following examples, but the present invention should not be construed as being limited to these examples.
Synthesis Example 1 (Production of isocyanate group-containing urethane prepolymer U-1 having an organic polyisocyanate monomer concentration of less than 1.0% by mass)
In a reaction vessel equipped with a stirrer, thermometer, nitrogen seal tube and heating / cooling device, 1330.3 g (OH) of polyoxypropylene triol (Exenol-4030, number average molecular weight 3,990 manufactured by Asahi Glass Co., Ltd.) under a nitrogen stream Equivalent: 1.000) was charged and stirred, 504.0 g of hexamethylene diisocyanate (HDI manufactured by Nippon Polyurethane Co., Ltd., molecular weight 168) (NCO equivalent: 6.000) (R value (NCO equivalent / OH equivalent) = 6.0) ) And 0.07 g of dibutyltin dilaurate, and then heated and stirred at 70 to 80 ° C. for 2 hours. When the isocyanate group content becomes less than the theoretical value (11.45% by mass), the reaction is performed. Then, an isocyanate group-containing urethane prepolymer was synthesized.
This isocyanate group-containing urethane prepolymer was a liquid transparent at room temperature with a measured isocyanate group content of 11.43% by mass and a viscosity of 700 mPa · s / 25 ° C. by titration.
Next, this isocyanate group-containing urethane prepolymer was distilled with a Smith type thin film distillation apparatus under the conditions of a contact temperature of 150 ° C., a reduced pressure of 400 Pa, a processing rate of 15 g / min, and a 2-pass condition, and a hexamethylene diisocyanate monomer concentration of 0.2 mass. % (HLC-8220 gel permeation chromatograph (GPC), THF, differential refractometer) manufactured by Tosoh Corporation, viscosity 4,500 mPa · s / 25 ° C., at a normal temperature with a measured isocyanate group content of 2.42 mass% by titration. An isocyanate group-containing urethane prepolymer U-1 having a residual organic polyisocyanate monomer concentration of the transparent liquid of less than 1.0 mass% by distillation was produced.

Synthesis Example 2 (Production of isocyanate group-containing urethane prepolymer U-2 having an organic polyisocyanate monomer concentration of less than 1.0% by mass)
In a reaction vessel similar to Synthesis Example 1, 1645.5 g (OH equivalent: 1.000) of polyoxypropylene triol (Preminol S3006, number average molecular weight 4,937 manufactured by Asahi Glass Co., Ltd.) was charged and stirred under a nitrogen stream. After adding 588.0 g of hexamethylene diisocyanate (HDI manufactured by Nippon Polyurethane Co., Ltd., molecular weight 168) (NCO equivalent: 7.000) (R value (NCO equivalent / OH equivalent) = 7.0) and 0.07 g of dibutyltin dilaurate Then, the mixture was heated and stirred at 70 to 80 ° C. for 2 hours. When the isocyanate group content became the theoretical value (11.28% by mass) or less, the reaction was terminated, and an isocyanate group-containing urethane prepolymer was synthesized. .
This isocyanate group-containing urethane prepolymer was a liquid transparent at room temperature with an isocyanate group content of 11.25 mass% measured by titration and a viscosity of 600 mPa · s / 25 ° C.
Next, this isocyanate group-containing urethane prepolymer was distilled with a Smith type thin film distillation apparatus under the conditions of a contact temperature of 150 ° C., a reduced pressure of 400 Pa, a processing rate of 15 g / min, and a 2-pass condition, and a hexamethylene diisocyanate monomer concentration of 0.2 mass. % (Tosoh HLC-8220 gel permeation chromatograph (GPC), THF, differential refractometer), viscosity 2,970 mPa · s / 25 ° C., measured by titration at ordinary temperature with isocyanate group content 2.09% by mass An isocyanate group-containing urethane prepolymer U-2 having a residual organic polyisocyanate monomer concentration of the transparent liquid of less than 1.0 mass% by distillation was produced.

Synthesis Example 3 (Production of isocyanate group-containing urethane prepolymer U-3 having an organic polyisocyanate monomer concentration of less than 1.0% by mass)
In a reaction vessel similar to Synthesis Example 1, 3339.9 g (OH equivalent: 1.000) of polyoxypropylene triol (Preminol S3011, number average molecular weight 10,020 manufactured by Asahi Glass Co., Ltd.) was charged and stirred under a nitrogen stream. After adding 1,008.0 g (NCO equivalent: 12.00) (R value (NCO equivalent / OH equivalent) = 12) of hexamethylene diisocyanate (HDI manufactured by Nippon Polyurethane Co., Ltd., molecular weight 168) and 0.07 g of dibutyltin dilaurate Then, the mixture was heated and stirred at 70 to 80 ° C. for 2 hours. When the isocyanate group content became the theoretical value (10.63 mass%) or less, the reaction was terminated, and an isocyanate group-containing urethane prepolymer was synthesized. .
This isocyanate group-containing urethane prepolymer was a liquid transparent at room temperature with a measured isocyanate group content of 10.60% by mass and a viscosity of 800 mPa · s / 25 ° C. by titration.
Next, this isocyanate group-containing urethane prepolymer was distilled with a Smith-type thin film distillation apparatus under the conditions of a contact temperature of 150 ° C., a reduced pressure of 400 Pa, a processing rate of 15 g / min, and a 2-pass condition, and a hexamethylene diisocyanate monomer concentration of 0.1 mass. % (Tosoh HLC-8220 Gel Permeation Chromatograph (GPC), THF, differential refractometer), viscosity 4,900 mPa · s / 25 ° C., measured by titration, normal isocyanate group content 0.90% by mass A socyanate group-containing urethane prepolymer U-3 having a residual organic polyisocyanate monomer concentration of the transparent liquid of less than 1.0 mass% by distillation was produced.

Synthesis Example 4 ( Synthesis of isocyanate group-containing urethane prepolymer U-4)
In a reaction vessel similar to Synthesis Example 1, 3339.9 g (OH equivalent: 1.000) of polyoxypropylene triol (Preminol S3011, number average molecular weight 10,020 manufactured by Asahi Glass Co., Ltd.) was charged and stirred under a nitrogen stream. After adding 168.0 g (NCO equivalent: 2.000) (R value (NCO equivalent / OH equivalent) = 2.0) of hexamethylene diisocyanate (HDI manufactured by Nippon Polyurethane Co., Ltd., molecular weight 168) and 0.07 g of dibutyltin dilaurate The mixture was heated and reacted at 70 to 80 ° C., but thickened during the reaction.

Synthesis Example 5 ( Synthesis of isocyanate group-containing urethane prepolymer U-5)
In a reaction vessel similar to Synthesis Example 1, 3339.9 g (OH equivalent: 1.000) of polyoxypropylene triol (Preminol S3011, number average molecular weight 10,020 manufactured by Asahi Glass Co., Ltd.) was charged and stirred under a nitrogen stream. After adding 504.0 g (NCO equivalent: 6.000) (R value (NCO equivalent / OH equivalent) = 6.0) of hexamethylene diisocyanate (HDI manufactured by Nippon Polyurethane Co., Ltd., molecular weight 168) and 0.07 g of dibutyltin dilaurate Then, the mixture was heated and stirred at 70 to 80 ° C. for 2 hours. When the isocyanate group content became the theoretical value (5.46% by mass) or less, the reaction was terminated, and the isocyanate group-containing urethane prepolymer U-5. Was synthesized.
This isocyanate group-containing urethane prepolymer U-5 has a measured isocyanate group content of 5.41% by mass by titration, a hexamethylene diisocyanate monomer concentration of 11.0% by mass (HLC-8220 gel permeation chromatograph (GPC) manufactured by Tosoh Corporation). , THF, differential refractometer), a viscosity of 5,750 mPa · s / 25 ° C., and a transparent liquid at room temperature.

Synthesis Example 6 ( Synthesis of neopentyl glycol silicate ester)
In a reaction vessel equipped with a stirrer, thermometer, nitrogen seal tube, reflux condenser and heating / cooling device, 312.5 g of neopentyl glycol, 3-glycidoxypropyltrimethoxysilane (manufactured by Nippon Unicar Company, A-187) ) 475.1 g and 0.001 g of tert-butyl titanate as a reaction catalyst were added, stirred and heated while flowing nitrogen gas, and refluxed for 2 hours. The liquid temperature decreased from 138 ° C to 100 ° C. Thereafter, the reflux condenser was removed, and heating was continued until 200 ° C. while distilling by-product methanol out of the system, and a light yellow color with no absorption by hydroxyl groups at 3,300 to 3,500 cm ⁻¹ by IR. 595.6 g of silicate liquid was obtained. The amount of methanol distilled was 192 g.
This liquid showed no neopentyl glycol peak even when subjected to gas chromatography (GC; oven 200 ° C., FID, Gascropack 55-column manufactured by Gaschrom Industries). As a reference, when the liquid was hydrolyzed and subjected to gas chromatography, the peak of neopentyl glycol was detected almost quantitatively, and it was confirmed that neopentyl glycol was regenerated.

Example 1
In a kneading vessel with a heating, cooling device and nitrogen seal tube, under a nitrogen stream, 100.0 g of an isocyanate group-containing urethane prepolymer U-1 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 1, hinder 1.0 g of dophenol antioxidant (pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]; Irganox 1010 manufactured by Ciba Specialty Chemicals), synthesis example 5.6 g of the neopentyl glycol silicate ester obtained in Step 6, 0.1 g of tin octenoate, and 0.06 g of dibutyltin bis (acetylacetonate) were stirred and mixed until the contents were uniform, and then the pressure was reduced. It degas | defoamed, the container was filled and sealed, and the moisture curable composition was prepared.

Example 2
In Example 1, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-1 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 1, the organic polyisocyanate monomer concentration obtained in Synthesis Example 2 was used. Moisture was similarly obtained except that 100.0 g of an isocyanate group-containing urethane prepolymer U-2 of less than 1.0% by mass was used and 5.2 g of neopentyl glycol silicate ester obtained in Synthesis Example 6 was used. A curable composition was prepared.

Example 3
In Example 1, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-1 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 1, the concentration of the organic polyisocyanate monomer obtained in Synthesis Example 3 was used. Moisture in the same manner except that 100.0 g of an isocyanate group-containing urethane prepolymer U-3 of less than 1.0% by mass and 2.1 g of neopentyl glycol silicate ester obtained in Synthesis Example 6 were used. A curable composition was prepared.

Example 4
In a kneading vessel equipped with a heating and cooling device and a nitrogen seal tube, 100.0 g of an isocyanate group-containing urethane prepolymer U-2 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 2 in advance under a nitrogen stream, 2.0 g of titanium oxide dried in a dryer at 90 to 100 ° C. to a moisture content of 0.05% by mass or less, similarly 80.0 g of calcium carbonate previously dried in a dryer, hindered phenol antioxidant ( 1.0 g of pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]; Ciba Specialty Chemicals Co., Ltd. Irganox 1010), neopentyl glycol obtained in Synthesis Example 6 Silicate ester of 5.2 g, tin octenoate 0.1 g, dibutyltin bis (acetylacetonate) 0 0.06 g was charged, stirred and mixed until the contents were uniform, then degassed under reduced pressure, filled in a container, and sealed to prepare a moisture curable composition.

Example 5
In Example 4, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-2 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 2, the concentration of the organic polyisocyanate monomer obtained in Synthesis Example 3 was used. Moisture in the same manner except that 100.0 g of an isocyanate group-containing urethane prepolymer U-3 of less than 1.0% by mass and 2.1 g of neopentyl glycol silicate ester obtained in Synthesis Example 6 were used. A curable composition was prepared.

Example 6
In Example 4, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-2 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 2, the concentration of the organic polyisocyanate monomer obtained in Synthesis Example 3 was used. 100.0 g of an isocyanate group-containing urethane prepolymer U-3 of less than 1.0% by mass was used and dried in a dryer at 90 to 100 ° C. in advance in place of 80.0 g of calcium carbonate, and the moisture content was 0.05% by mass. Moisture curable in the same manner except that 80.0 g of the following surface-treated calcium carbonate (Calfine 200M manufactured by Maruo Calcium Co., Ltd.) was used and 2.1 g of neopentyl glycol silicate ester obtained in Synthesis Example 6 was used. A composition was prepared.

Comparative Example 1
In Example 1, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-1 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 1, the isocyanate group-containing urethane prepolymer obtained in Synthesis Example 5 was used. A moisture curable composition was prepared in the same manner except that 100.0 g of the polymer U-5 was used and 12.7 g of the neopentyl glycol silicate ester obtained in Synthesis Example 6 was used.

Comparative Example 2
In Example 4, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-2 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 2, the isocyanate group-containing urethane prepolymer obtained in Synthesis Example 5 was used. A moisture curable composition was prepared in the same manner except that 100.0 g of the polymer U-5 was used and 12.7 g of the neopentyl glycol silicate ester obtained in Synthesis Example 6 was used.

Comparative Example 3
In Example 6, instead of 100.0 g of the isocyanate group-containing urethane prepolymer U-3 having an organic polyisocyanate monomer concentration of less than 1.0% by mass obtained in Synthesis Example 3, the isocyanate group-containing urethane prepolymer obtained in Synthesis Example 5 was used. A moisture curable composition was prepared in the same manner except that 100.0 g of the polymer U-5 was used and 12.7 g of the neopentyl glycol silicate ester obtained in Synthesis Example 6 was used.

Measurement of Viscosity of Isocyanate Group-Containing Urethane Prepolymer Using a B8M type rotational viscometer, the value was measured after 1 minute of starting at 12 revolutions per minute with a No4 rotor after immersion in a water bath at 25 ° C. for 1 hour.
Performance test (1) Tack-free time In accordance with “4.19 Tack-free test” in JIS A1439: 1997 “Testing method for sealing material for building”, tack-free time at 23 ° C. and 50% relative humidity was measured.
(2) Internal Curing The moisture curable composition is filled into three polypropylene containers having a width of 90 mm, a depth of 60 mm and a length of 120 mm, and the excess moisture curable composition is flattened with a spatula. C., 40% relative humidity, 23.degree. C., 50% relative humidity, 35.degree. C., and 70% relative humidity. 24 hours after filling, it was cut so as to be perpendicular to the length direction, the uncured layer was carefully removed and cured from the surface, and the thickness of the portion forming the cured product layer was measured.
(3) Slump The slump (longitudinal) at 23 ° C. and 50% relative humidity was measured according to “4.1 slump test” of JIS A1439: 1997 “Testing method of sealing material for building”.
(4) Foaming The moisture-curing composition was poured or filled in a paper cup (205 ml in capacity) so that no bubbles (depth of about 40 mm) were involved, and cured and cured at 23 ° C. and 50% relative humidity for 7 days. The test specimens were visually observed.
A case in which significant blistering due to foaming was not observed or extremely small was evaluated as ◯, and a case where a large number of blisters were observed was evaluated as ×.
(5) Hardness Hardness was measured with a spring-type hardness meter (Shore A) at 23 ° C. and 50% relative humidity. The moisture curable composition was carefully poured or filled in a paper cup (capacity 205 ml) so as not to entrap bubbles, and the depth was about 20 mm. Next, the specimen was cured by curing at 23 ° C. and 50% relative humidity for 7 days.
The measurement results were measured at five points, and the average value of three points excluding the maximum value and the minimum value was rounded to an integer.
(6) Tensile Adhesion Measured at 23 ° C. and 50% relative humidity in accordance with “4.21 Tensile Adhesion Test” of JIS A1439: 1997 “Testing Method of Sealant for Building”. The test specimen was treated with a slate with a primer (OP-2531, manufactured by Auto Chemical Industry Co., Ltd.), a moisture curable composition was placed thereon, and the test specimen after placement was 7 ° C. and 7% at 50% relative humidity. Prepared by curing for days.
The raw material composition of the moisture curable composition and its performance are summarized in Tables 1 to 3.

Claims (9)

A moisture curable composition comprising an isocyanate group-containing urethane prepolymer (A) and an organic compound (B) capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture,
The moisture curable composition, wherein the isocyanate group-containing urethane prepolymer (A) is an isocyanate group-containing urethane prepolymer having an organic polyisocyanate monomer concentration of less than 1.0% by mass.   The isocyanate group-containing urethane prepolymer (A) having an organic polyisocyanate monomer concentration of less than 1.0% by mass reacts with an aliphatic diisocyanate and a polyol having a number average molecular weight of 1,000 to 50,000, and then unreacted. The moisture-curable composition according to claim 1, which is an isocyanate group-containing urethane prepolymer in which the aliphatic diisocyanate monomer is removed by distillation to make the residual aliphatic diisocyanate monomer concentration less than 1.0% by mass.   The organic compound (B) capable of regenerating the active hydrogen group-containing compound by hydrolysis with moisture is a silicate ester compound capable of regenerating the active hydrogen group-containing compound by hydrolysis with moisture. The moisture-curable composition according to claim 1 or 2.   The moisture-curable composition according to claim 3, wherein the silicate compound is a silicate compound obtained by a dealcoholization reaction between the polyol (b1) and the alkoxysilyl group-containing compound (b2).   Furthermore, the moisture curable composition as described in any one of Claims 1-4 containing a hardening accelerator (C).   The moisture-curable composition according to claim 5, wherein the curing accelerator (C) is a tin-based curing accelerator.   The moisture-curable composition according to claim 6, wherein the tin-based curing accelerator is an organic tin compound and a tin chelate compound.   Further, one kind selected from the group consisting of a filler, a plasticizer, a weather resistance stabilizer, a thixotropic agent, an adhesion promoter, a storage stability improver, an oxygen curable compound, a design agent, a solvent and a colorant. Or the moisture-curable composition as described in any one of Claims 1-7 which mix | blends 2 or more types of additives. A moisture curable sealant composition comprising an isocyanate group-containing urethane prepolymer (A) and an organic compound (B) capable of regenerating an active hydrogen group-containing compound by hydrolysis with moisture,
The moisture curable sealant composition, wherein the isocyanate group-containing urethane prepolymer (A) is an isocyanate group-containing urethane prepolymer having an organic polyisocyanate monomer concentration of less than 1.0% by mass.