JP6836032B2 - Curable composition - Google Patents

Description

The present invention relates to a curable composition having excellent workability, antifouling property, weather resistance, and rubber physical characteristics.

A curable composition containing a polyurethane resin, a silicone resin, a modified silicone resin, or a polysulfide resin as a curing component is used as a sealing material composition, a waterproof material composition, or a coating material composition for construction, civil engineering, automobiles, etc. Has been done. Among them, a curable composition containing a polyurethane resin or a modified silicone resin as a curing component is widely used for construction and civil engineering because it has good workability, excellent rubber physical characteristics after curing, and excellent adhesiveness to various members. ing. When the curable composition is used for construction or civil engineering, it is often directly exposed to sunlight or rainwater, and a curable composition having excellent weather resistance is desired. As a method for imparting weather resistance to a curable composition, a method of blending a weather-resistant stabilizer such as a hindered phenol-based antioxidant, an ultraviolet absorber, and a hindered amine-based light stabilizer with a curable composition has been conventionally known. (Patent Document 1, Patent Document 2). However, the curable composition containing these weather-resistant stabilizers does not always satisfy the long-term weather resistance (needs for long life) required in recent years, and other methods for improving the long-term weather resistance. Is required. In addition, when the cured product is used for a long period of time, the rubber physical characteristics of the cured product tend to gradually harden, which causes cracks in the cured product and peeling from the members. Therefore, the rubber physical properties are low modulus and high elongation. Those having the above are desired.

Further, a curable composition containing a polyurethane resin or a modified silicone resin as a curing component often contains a plasticizer such as dioctyl phthalate in order to improve workability and adjust the physical characteristics of rubber after curing. However, when a curable composition containing a plasticizer is cured, the plasticizer may seep out from the cured product over time, causing problems. For example, when the plasticizer is transferred to the surface of the cured product, the surface of the cured product becomes sticky, dust, dust, etc. adhere to the surface, and the surface is contaminated. Further, even when the topcoat paint is applied to the surface of the cured product, it shifts to the topcoat paint (coating film), and the surface of the topcoat coating film becomes sticky, and dust, dust, etc. adhere to the surface and contaminate the surface. Further, the plasticizer may be transferred to the member (adhered member) around the cured product, and the surface of the member is similarly contaminated. As described above, when the plasticizer is transferred from the cured product, the cured product gradually becomes hard and fragile, and there is a problem that the plasticizer is peeled off from the members around the cured product.

Japanese Unexamined Patent Publication No. 2002-348436 Japanese Unexamined Patent Publication No. 2001-342341

An object of the present invention is to provide a curable composition having excellent workability, antifouling property, weather resistance, and rubber physical characteristics.

As a result of diligent studies to solve the above-mentioned problems, the present inventors have found a curable composition containing a room temperature curable resin and a compound having a nitroxide free radical having a number average molecular weight of 2,000 or more. The present invention has been completed by finding that it is excellent in workability, antifouling property, weather resistance, and rubber physical properties. That is, the present invention is as shown in (1) to (7) below.
(1) A curable composition containing a room temperature curable resin and a compound having a nitroxide radical having a number average molecular weight of 2,000 or more.
(2) The curable composition according to (1), wherein the room temperature curable resin is an isocyanate group-containing resin or a crosslinkable silyl group-containing resin.
(3) The compound having a nitroxide free radical having a number average molecular weight of 2,000 or more is a compound having a nitroxide free radical having a number average molecular weight of 2,000 or more and a piperidine ring (1) or (2). ). The curable composition.
(4) The compound having a nitroxide radical having a number average molecular weight of 2,000 or more is a polyoxyalkylene compound having a nitroxide radical having a number average molecular weight of 2,000 or more and / or a nitroxide having a number average molecular weight of 2,000 or more. The curable composition according to any one of (1) to (3), which is a poly (meth) acrylic compound having a free radical.
(5) Further, at least one selected from a curing acceleration catalyst, a plasticizer, a weather resistance stabilizer, a filler, a rock denaturing agent, an adhesiveness improver, a storage stability improver (dehydrating agent), a colorant and an organic solvent. The curable composition according to any one of (1) to (4), which contains one or more additives.
(6) The curable composition according to any one of (1) to (5), wherein the curable composition is a curable composition for construction or civil engineering.
(7) The curable composition according to any one of (1) to (6), wherein the curable composition is a sealing material composition, a waterproof material composition or a coating material composition.

The curable composition of the present invention is excellent in workability, antifouling property, weather resistance, and rubber physical characteristics, and can be suitably used as a sealing material composition, a waterproof material composition, and a coating material composition.

Hereinafter, the present invention will be described in detail according to an embodiment.

The present invention is a curable composition comprising a room temperature curable resin and a compound having a nitroxide radical having a number average molecular weight of 2,000 or more. Hereinafter, each component will be described in detail.

The room temperature curable resin is one in which the curable resin reacts with an active hydrogen-containing compound or the like (for example, water such as humidity) to be crosslinked and cured at least at room temperature. In the present invention, the normal temperature means the normal temperature (5 to 35 ° C.) described in JIS Z 8703 (1983). Further, even a curable resin that reacts with an active hydrogen-containing compound and is cross-linked and cured at a temperature of less than 5 ° C or higher than 35 ° C, is curable by reacting with an active hydrogen-containing compound at room temperature (5-35 ° C) and cross-linked and cured. If it is a resin, it is included in the room temperature curable resin.

The room temperature curable resin is not particularly limited as long as it is crosslinked and cured by reacting with an active hydrogen-containing compound or the like at room temperature. Specific examples thereof include isocyanate group-containing resins and crosslinkable (hydrolyzable) silyl group-containing resins.

The isocyanate group-containing resin is a resin having one or more isocyanate groups in the resin, and the isocyanate groups react with active hydrogen (groups) to form urethane bonds, urea bonds, and the like, and cross-linking and curing. The isocyanate group-containing resin is simply "urethane prepolymer" including an isocyanate group-containing urethane prepolymer (hereinafter, an isocyanate group-containing urethane prepolymer and an isocyanate group-containing urethane prepolymer having a photoreactive unsaturated bond introduced later). In some cases,) can be preferably mentioned.

The isocyanate group-containing urethane prepolymer has an organic isocyanate compound and an active hydrogen-containing compound having an isocyanate group / active hydrogen molar ratio of preferably 1.2 to 10/1, more preferably 1.2 to 5/1. It can be produced by reacting all at once or sequentially in a range so that the isocyanate group remains in the urethane prepolymer. If the molar ratio is less than 1.2 / 1, the viscosity of the urethane prepolymer becomes high, and the workability of the curable composition deteriorates. On the other hand, if the molar ratio exceeds 10/1, the amount of carbon dioxide gas generated when the isocyanate group reacts with water increases, which causes foaming during curing.

The isocyanate group content in the isocyanate group-containing urethane prepolymer is preferably 0.3 to 15% by mass, and particularly preferably 0.5 to 5% by mass. When the isocyanate group content is less than 0.3% by mass, the viscosity of the urethane prepolymer becomes high and the workability of the curable composition deteriorates. When the isocyanate group content exceeds 15% by mass, the amount of carbon dioxide gas generated when the isocyanate group reacts with water increases, which causes foaming during curing.

The number average molecular weight of the isocyanate group-containing urethane prepolymer is preferably 1,500 or more, more preferably 1,500 to 20,000, further preferably 1,500 to 15,000, and particularly preferably 1,500 to 10,000. preferable. The number average molecular weight in the present invention is a polystyrene-equivalent value measured by gel permeation chromatography (GPC).

Specifically, as a method for producing an isocyanate group-containing urethane prepolymer, an organic isocyanate compound and an active hydrogen-containing compound are charged in a reaction vessel made of glass or stainless steel, and the reaction catalyst or organic solvent is present or absent. Below, there is a method of reacting with stirring at 50 to 120 ° C. At this time, since the urethane prepolymer thickens when the isocyanate group reacts with water such as moisture, it is preferable to replace the inside of the container with nitrogen gas in advance or to carry out the reaction under a nitrogen gas stream.

Examples of the organic isocyanate compound include organic polyisocyanate. The organic polyisocyanate is a compound having two or more isocyanate groups in the compound, and specifically, toluene polyisocyanate such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, 4,4'-. Diphenylmethane polyisocyanate such as diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 1,2-phenylenediocyanate, 1,3-phenylenediocyanate, 1,4-phenylenediocyanate, 2,4,6 Phenylene polyisocyanates such as −trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, naphthalene polyisocyanates such as 1,4-naphthalenediocyanate and 1,5-naphthalenediocyanate, Fragrances such as chlorophenylene-2,4-diisocyanate, 4,4'-diphenylether diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 3,3'-dimethoxydiphenyl-4,4'-diisocyanate Polyisocyanate can be mentioned. In addition, 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, Aliphatic polyisocyanates such as decamethylene diisocyanate and lysine diisocyanate, aromatic aliphatic polyisocyanates such as o-xylylene diisocyanate, m-xylylene diisocyanate, and p-xylylene diisocyanate, 1,4-cyclohexyldiisocyanate, isophorone diisocyanate, and hydrogenation. Examples thereof include alicyclic polyisocyanates such as toluene diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Further, polypeptide isocyanates such as polymethylene polyphenyl polyisocyanate and crude toluene diisocyanate can be mentioned. Furthermore, modified isocyanates obtained by modifying these organic polyisocyanates and having one or more uretdione bond, isocyanurate bond, allophanate bond, bullet bond, uretonimine bond, carbodiimide bond, urethane bond or urea bond can be mentioned. All of these can be used alone or in combination of two or more.

Of these, aliphatic polyisocyanates, aromatic aliphatic polyisocyanates, alicyclic polyisocyanates, and modified isocyanates obtained by modifying these organic polyisocyanates are preferable because the curable composition is excellent in weather resistance.

Moreover, organic monoisocyanate can be used together with organic polyisocyanate. That is, a mixture of organic polyisocyanate and organic monoisocyanate can be used as the above-mentioned organic isocyanate compound. The organic monoisocyanate is a compound having one isocyanate group in the compound, and specifically, n-butyl monoisocyanate, n-hexyl monoisocyanate, n-hexadecyl monoisocyanate, n-octadecyl monoisocyanate and the like. Examples of the aliphatic monoisocyanate, p-isopropylphenylmonoisocyanate, and p-benzyloxyphenylmonoisocyanate.

An active hydrogen-containing compound is a compound having one or more active hydrogens (groups) in the compound. Specifically, in addition to high molecular weight polyols and high molecular weight polyamines, low molecular weight polyols used as chain extenders, low molecular weight amino alcohols, low molecular weight polyamines, and high molecular weight and low molecular weight compounds used for modification of urethane prepolymers. Monool can be mentioned.

Examples of the polymer polyol include polyester polyol, polycarbonate polyol, polyoxyalkylene-based polyol, poly (meth) acrylic polyol, hydrocarbon-based polyol, animal and plant-based polyol, and copolyol thereof. In the present invention, "(meth) acrylic" means "acrylic and / or methacrylic".

The number average molecular weight of the polymer polyol is preferably 1,000 to 30,000, more preferably 1,000 to 20,000.

Examples of polyester polyols include succinic acid, adipic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid, orthophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, hexahydroorthophthalic acid, naphthalenedicarboxylic acid, trimellitic acid and the like. Polycarboxylic acids; one or more of the anhydrides of these acids or alkyl esters such as methyl esters and ethyl esters, and ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, One or more of low molecular weight polyols such as 1,9-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, ethylene oxide or propylene oxide adduct of bisphenol A, trimethylpropane, glycerin, pentaerythritol, etc. Examples thereof include polyester polyols obtained by the reaction with. Further, in addition to these polycarboxylic acids and acid anhydrides and low molecular weight polyols, low molecular weight polyamines such as butylene diamine, hexamethylene diamine, xylylene diamine and isophorone diamine, and low molecular weight molecules such as monoethanolamine and diethanolamine. Examples thereof include polyesteramide polyols obtained by reacting with one or more of amino alcohols.

Furthermore, lactone-based polyester polyols obtained by ring-opening polymerization of cyclic ester (lactone) monomers such as ε-caprolactone and γ-valerolactone using low-molecular-weight polyols, low-molecular-weight polyamines, and low-molecular-weight amino alcohols as initiators are also available. Can be mentioned.

As the polycarbonate polyol, a dehydrochloration reaction between the low molecular weight polyols used in the synthesis of the polyester polyol described above and phosgene, or a transesterification reaction between the low molecular weight polyols described above and diethylene carbonate, dimethyl carbonate, diethyl carbonate, or diphenyl carbonate. Can be obtained from.

Examples of the polyoxyalkylene-based polyol include low-molecular-weight polyols, low-molecular-weight polyamines, low-molecular-weight amino alcohols, and polycarboxylic acids similar to those used for the synthesis of the polyester polyol described above; sorbitol, mannitol, and sucrose ( Sugar-based low-molecular-weight polyhydric alcohols such as sucrose) and glucose; cyclic ethers such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran, starting with one or more of low-molecular-weight polyvalent phenols such as bisphenol A and bisphenol F. A polyoxyethylene-based polyol, a polyoxypropylene-based polyol, or a polyoxybutylene-based polyol obtained by subjecting one or more of the compounds to ring-open addition polymerization or copolymerization (hereinafter, "polymerization or copolymerization" is referred to as (co) polymerization). , Polyoxytetramethylene-based polyols, poly- (oxyethylene)-(oxypropylene) -random or block copolymer-based polyols, and polyester ether polyols and polycarbonate ether polyols using the above-mentioned polyester polyols and polycarbonate polyols as initiators. Can be mentioned. In addition, a polyol obtained by reacting these various polyols with an organic isocyanate compound with an excess hydroxyl group with an isocyanate group to have a hydroxyl group at the molecular end can be mentioned.

The number of alcoholic hydroxyl groups in the polyoxyalkylene-based polyol is preferably 2 or more, more preferably 2 to 4, and particularly preferably 2 to 3 in one molecule.

The catalysts for synthesizing polyoxyalkylene-based polyols are alkali metal compound catalysts such as sodium-based catalysts and potassium-based catalysts, cationic polymerization catalysts, and composite metal cyanation complex catalysts such as zinc hexacyanocobaltate glyme complex and diglyme complex. Examples include phosphazene compound catalysts. Of these, alkali metal compound catalysts and composite metal cyanide complex catalysts are preferable. Further, a polyoxyalkylene-based polyol synthesized by using a composite cyanide complex catalyst is preferable because it has a low total unsaturation degree and a low viscosity of the polyol.

The total degree of unsaturation of the polyoxyalkylene-based polyol is preferably 0.1 meq / g or less. The molecular weight distribution of the polyoxyalkylene-based polyol [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. It is preferable, and 1 to 1.3 is particularly preferable. By setting the total degree of unsaturation and the molecular weight distribution of the polyoxyalkylene-based polyol within the above ranges, the viscosity of the obtained urethane prepolymer can be reduced, and the workability of the curable composition is improved. In addition, the rubber physical properties of the curable composition after curing are low modulus and high elongation.

Further, for modification of urethane prepolymers, polyoxypropylene-based products obtained by ring-opening addition polymerization of cyclic ether compounds such as propylene oxide using low-molecular-weight monoalcohols such as methyl alcohol, ethyl alcohol and propyl alcohol as initiators. Polyoxyalkylene-based monools such as oars can also be used. The number average molecular weight of the polyoxyalkylene monool is preferably 1,000 to 10,000.

The "system" of the above-mentioned polyoxyalkylene-based polyol or polyoxyalkylene-based monool is 50% by mass or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more of the portion of the molecule excluding the hydroxyl group. If is composed of polyoxyalkylene, it means that the remaining portion may be modified with ester, urethane, polycarbonate, polyamide, poly (meth) acrylate, polyolefin, etc., but the molecule excluding the hydroxyl group Most preferably, 95% by mass or more is composed of polyoxyalkylene. In the present invention, "(meth) acrylate" means "acrylate and / or methacrylate".

The poly (meth) acrylic polyol is a radical polymerization of a hydroxyl group-containing (meth) acrylic monomer and another ethylenically unsaturated compound in the presence or absence of a solvent, such as a batch type or continuous polymerization. It is obtained by copolymerization by the method of. Furthermore, the product obtained by performing a continuous massive copolymer reaction at a high temperature of 150 to 350 ° C., more preferably 210 to 250 ° C. in the absence of a solvent has a narrow molecular weight distribution of the reaction product and a low viscosity. Therefore, it is preferable. At the time of this copolymerization, it is preferable to use the hydroxyl group-containing (meth) acrylic monomer so that the average number of hydroxyl groups per molecule of the poly (meth) acrylic polyol is 1.2 to 10; It is preferable to use it so as to contain 2 to 6 pieces. If the average number of hydroxyl groups is less than 1.2, the adhesiveness of the obtained curable composition after curing is lowered, and if it exceeds 10, the curable composition becomes brittle, which is not preferable. The glass transition point (Tg) of the poly (meth) acrylic polyol is preferably 50 ° C. or lower, more preferably 0 ° C. or lower, still more preferably −70 to −20 ° C., and particularly preferably −70 to −30 ° C.

The hydroxyl group-containing (meth) acrylic monomer is a (meth) acrylic monomer having at least one hydroxyl group in the molecule, and specifically, hydroxyethyl (meth) acrylate and hydroxypropyl (meth). Hydroxyalkyl (meth) acrylates such as acrylates and hydroxybutyl (meth) acrylates; pentaerythritol tri (meth) acrylate, glycerin mono (meth) acrylate, pentaerythritol di (meth) acrylate monostearate, dipentaerythritol penta (meth). ) Mono (meth) acrylates of polyhydric alcohols such as acrylates, ditrimethylolpropantri (meth) acrylates, polypropylene glycol mono (meth) acrylates, and polyvalent (meth) acrylates with residual hydroxyl groups. These can be used alone or in combination of two or more. Of these, hydroxyalkyl (meth) acrylates are preferable because the viscosity of the (meth) acrylic polyol is low and the reactivity with the isocyanate group is good. Further, hydroxyethyl (meth) acrylate is preferable.
Examples of the ethylenically unsaturated compound other than the hydroxyl group-containing (meth) acrylic monomer include (meth) acrylic monomer and other ethylenically unsaturated compounds. Examples of the ethylenic compound other than the (meth) acrylic monomer include vinyl compounds such as ethylene, propylene, isobutylene, butadiene, chloroprene, styrene, chlorostyrene, 2-methylstyrene, and divinylbenzene. Examples of the (meth) acrylic monomer include (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, and (meth) acrylate. 2-Ethylhexyl, benzyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, tridecyl (meth) acrylate, ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neo Pentyl glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, tripropylene Examples thereof include glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, glycidyl tri (meth) acrylate, and trimethyl propantri (meth) acrylate. These can be used alone or in combination of two or more. Of these, the monomer of the (meth) acrylic acid ester-based compound is preferable in that the viscosity of the (meth) acrylic polyol is low, and further, methyl (meth) acrylate, ethyl (meth) acrylate, and propyl (meth) acrylate. , Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate are preferred. In the present invention, "(meth) acrylic acid" means "acrylic acid and / or methacrylic acid".

Examples of the hydrocarbon-based polyol include polyolefin polyols such as polybutadiene polyols and polyisoprene polyols; polyalkylene polyols such as hydrogenated polybutadiene polyols and hydrogenated polyisoprene polyols; halogenated polyalkylene polyols such as chlorinated polypropylene polyols and chlorinated polyethylene polyols. Can be mentioned.

Examples of animal and plant-based polyols include castor oil-based polyols and silk fibroin.

Any of the above-mentioned polymer polyols can be used alone or in combination of two or more. Of these, polyoxyalkylene-based polyols and poly (meth) acrylic polyols are preferable in terms of good rubber physical characteristics and adhesiveness of the obtained curable composition.

The isocyanate group-containing urethane prepolymer can also introduce a photoreactive unsaturated bond into the urethane prepolymer for the purpose of imparting weather resistance. The urethane prepolymer in which a photoreactive unsaturated bond is introduced acts as a curing component in the curable composition of the present invention, and at the same time, imparts good adhesion to the adherend surface and excellent weather resistance to the cured composition. It is a thing. The above-mentioned photoreactive unsaturated bond is an unsaturated bond that causes a chemical change such as polymerization in a relatively short time when exposed to light. Specific examples thereof include unsaturated bonds derived from vinyl groups, vinylene groups, and (meth) acryloyl groups. In the present invention, the "(meth) acryloyl group" means "acryloyl group and / or methacryloyl group".

The isocyanate group of the isocyanate group-containing urethane prepolymer into which a photoreactive unsaturated bond has been introduced reacts with an active hydrogen-containing compound and is crosslinked and cured. In addition, the photoreactive unsaturated bond of the isocyanate group-containing urethane prepolymer into which a photoreactive unsaturated bond has been introduced undergoes a polymerization reaction when exposed to light, forming a cured film having excellent weather resistance on the surface of the curable composition. Form. It is considered that this cured film imparts excellent weather resistance to the curable composition. As the photoreactive unsaturated bond, an unsaturated bond derived from a (meth) acryloyl group is preferable because it has a high effect of imparting weather resistance.

As a method of introducing a photoreactive unsaturated bond into an isocyanate group-containing urethane prepolymer,
(B) Organic isocyanate compounds, high molecular weight active hydrogen-containing compounds (number average molecular weight of 1,000 or more), and low-molecular-weight active hydrogen-containing compounds (number) having active hydrogen and photoreactive unsaturated bonds in the molecule. A method obtained by reacting a total amount of active hydrogen with an average molecular weight of less than 1,000) under the condition of an excess of isocyanate groups.
(B) An organic isocyanate compound and an active hydrogen-containing compound of a polymer (number average molecular weight of 1,000 or more) having an active hydrogen and a photoreactive unsaturated bond in the molecule (for example, a mono (meth) of polyoxyalkylene triol. ) A method obtained by reacting an acrylate, an alkylene oxide adduct of (meth) acrylic acid, and a polybutadiene polyol) with an excess amount of isocyanate groups with respect to the total amount of active hydrogen.
(C) An organic isocyanate compound, a low molecular weight (number average molecular weight less than 1,000) active hydrogen-containing compound (for example, (meth) acryloyl isocyanate) having a photoreactive unsaturated bond and an isocyanate group in the molecule, and A method obtained by reacting a high molecular weight (number average molecular weight of 1,000 or more) active hydrogen-containing compound with the total amount of active hydrogen under the condition of excess isocyanate group.
Can be mentioned. The method (a) described above is preferable in terms of availability of raw materials and ease of reaction. Examples of the polymer active hydrogen-containing compound include high molecular weight polyols (for example, polyoxyalkylene-based polyols and poly (meth) acrylic polyols) that can be used in producing urethane prepolymers.

Examples of the method of introducing a photoreactive unsaturated bond into an isocyanate group-containing urethane prepolymer include a method of charging and reacting each of the above-mentioned raw materials in a batch or sequentially. The molar ratio (isocyanate group / active hydrogen) of the isocyanate group of the organic isocyanate compound to the active hydrogen of the active hydrogen-containing compound (including the active hydrogen-containing compound having an active hydrogen and a photoreactive unsaturated bond) is 1. .2 to 10/1 is preferable, and 1.2 to 5/1 is more preferable. The isocyanate group content in the isocyanate group-containing urethane prepolymer into which a photoreactive unsaturated bond has been introduced is preferably 0.3 to 15% by mass, more preferably 0.5 to 5% by mass. When the isocyanate group content is less than 0.3% by mass, the molecular weight becomes too large, the viscosity increases, and the workability deteriorates. Further, since the number of cross-linking points in the urethane prepolymer is reduced, sufficient adhesiveness cannot be obtained. If the isocyanate group content exceeds 15% by mass, the amount of carbon dioxide gas generated when the isocyanate group reacts with water increases, which causes foaming during curing.

The concentration of the photoreactive unsaturated bond in the isocyanate group-containing urethane prepolymer into which the photoreactive unsaturated bond has been introduced is preferably 0.01 mmol / g or more, more preferably 0.03 to 1 mmol / g, and particularly preferably 0.03 to 1 mmol / g. It is preferably 0.05 to 0.5 mmol / g.

Compounds (low molecular weight and high molecular weight) having active hydrogen and photoreactive unsaturated bonds include active hydrogen (groups) such as hydroxyl groups, amino groups, and carboxyl groups, vinyl groups, vinylene groups, and (meth) in the compounds. ) A compound having both a photoreactive unsaturated bond such as an acryloyl group, and having a hydroxyl group and a (meth) acryloyl group in the compound is preferable in terms of ease of reaction and high effect of imparting weather resistance. Further, the molecular weight of the compound having an active hydrogen (group) and a photoreactive unsaturated bond is preferably one having a number average molecular weight of less than 1,000 in terms of easy reaction.

Examples of the compound having a hydroxyl group and a (meth) acryloyl group include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate, which are monoesters of alkylene glycols such as ethylene glycol, propylene glycol and butylene glycol and (meth) acrylic acid. Hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 4-hydroxypentyl (meth) acrylate, hydroxyneopentyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate , Monohydroxymono (meth) acrylates such as hydroxyheptyl (meth) acrylate and hydroxyoctyl (meth) acrylate, monoesters of trifunctional or higher alkylene polyols such as glycerin, trimethylolpropane, pentaerythritol and (meth) acrylic acid. Alternatively, monohydroxypoly (meth) acrylates such as glycerin di (meth) acrylate, trimethylpropandi (meth) acrylate, pentaerythritol tri (meth) acrylate, and glycerin mono (meth) which are polyesters such as diester and triester. Examples thereof include polyhydroxymono (meth) acrylates such as acrylates, trimethylolpropane mono (meth) acrylates and pentaerythritol mono (meth) acrylates, and polyhydroxypoly (meth) acrylates such as pentaerythritol di (meth) acrylates. In addition to these, monohydroxymonos (meth) such as diethylene glycol, dipropylene glycol, polyoxyethylene polyol, polyoxypropylene polyol, and polyols obtained by adding alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide to bisphenol A and bisphenol F. ) Acrylate, polyhydroxymono (meth) acrylate, polyhydroxypoly (meth) acrylate, ethylene oxide, propylene oxide, active hydrogen of hydroxyalkyl (meth) acrylate such as (meth) acrylic acid and hydroxyethyl (meth) acrylate. , Butylene oxide and other compounds to which alkylene oxide is added and having a hydroxyl group, and caprolactone-modified products of hydroxyethyl acrylate and which have a hydroxyl group can also be mentioned. These can be used alone or in combination of two or more. Of these, monohydroxypoly (meth) acrylates and dihydroxypoly (meth) acrylates are preferable in that the viscosity of the urethane prepolymer can be suppressed to a low level and the effect of imparting weather resistance can be enhanced.

The crosslinkable silyl group-containing resin is a resin having at least one crosslinkable (hydrolytable) silyl group in the resin, and the crosslinkable silyl group reacts with an active hydrogen (group) to form a siloxane bond. It is crosslinked and cured to become a cured product. Examples of the crosslinkable silyl group-containing resin include those generally called silicone resin or modified silicone resin. In particular, a modified silicone resin can be preferably mentioned.

The silicone resin has an organopolysiloxane as the main chain and has a crosslinkable silyl group in the resin. Specifically, a one-component silicone resin containing an organopolysiloxane having a silanol group at the terminal as a main component and a low molecular weight compound containing a crosslinkable silyl group as a cross-linking component, and an organopoly having a silanol group at the terminal as a main component. Examples thereof include a two-component silicone resin containing siloxane and aminoxylalkylsilane as a curing agent. Examples of the crosslinkable silyl group-containing low molecular weight compound include acyloxyalkylsilane, aminoxyalkylsilane, and alkoxyalkylsilane.

Examples of the modified silicone resin include JP-A-52-73998, JP-A-55-9669, JP-A-59-122541, JP-A-60-6747, and JP-A-61-234033. Japanese Patent Application Laid-Open No. 63-6003, Japanese Patent Application Laid-Open No. 63-112642, Japanese Patent Application Laid-Open No. 3-79627, Japanese Patent Application Laid-Open No. 4-283259, Japanese Patent Application Laid-Open No. 5-287186, Japanese Patent Application Laid-Open No. 11-80571 , JP-A-11-116763, and JP-A-11-130931. Specifically, it has a crosslinkable silyl group in the resin, and the main chain is an aliphatic charcoal hydrated hydrogen-based heavy weight such as a vinyl-based polymer, a polyoxyalkylene-based polymer, polyisobutylene, polyisobutylene, and polybutandien. Examples thereof include coalescing, polyester-based polymers, polysulfide polymers, copolymers thereof, and mixtures thereof. All of these can be used alone or in combination of two or more.

The main chain of the modified silicone resin is a polyoxyalkylene polymer, a (meth) acrylic-modified polyoxyalkylene polymer, or (meth) from the viewpoint of tensile adhesiveness after curing and rubber properties such as modulus. ) Acrylic copolymer is preferable.

In the present invention, "may be (meth) acrylic-modified" means a polyoxypropylene-based polymer obtained by blocking or pendant copolymerizing a (meth) acrylic monomer, or a polyoxyalkylene-based polymer. It means a mixture of a (meth) acrylic copolymer and a polymer of a (meth) acrylic monomer in a polyoxyalkylene polymer having a crosslinkable silyl group introduced therein.

From the viewpoint of curability and physical properties after curing of the curable composition, the crosslinkable silyl group is preferably contained in an amount of 1 or more, more preferably 1 to 5, and particularly 1 to 3. It is preferably included.
Further, the crosslinkable silyl group is preferably one represented by the following general formula, which is easy to crosslink and easy to produce.

（式中、Ｒは炭化水素基であり、炭素数１〜２０のアルキル基、炭素数６〜２０のアリール基または炭素数７〜２０のアラルキル基が好ましく、メチル基が最も好ましい。Ｘで示される反応性基はハロゲン原子、水素原子、水酸基、アルコキシ基、アシルオキシ基、ケトキシメート基、アミド基、酸アミド基、メルカプト基、アルケニルオキシ基およびアミノオキシ基より選ばれる加水分解性の基であり、Ｘが複数の場合には、Ｘは同じ基であっても異なった基であってもよい。このうちＸはアルコキシ基が好ましく、メトキシ基またはエトキシ基が最も好ましい。ａは０、１または２の整数であり、０または１が最も好ましい。）

(In the formula, R is a hydrocarbon group, preferably an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and most preferably a methyl group. Reactive groups are hydrolyzable groups selected from halogen atoms, hydrogen atoms, hydroxyl groups, alkoxy groups, acyloxy groups, ketoximate groups, amide groups, acid amide groups, mercapto groups, alkenyloxy groups and aminooxy groups. When there are a plurality of Xs, X may be the same group or different groups. Of these, X is preferably an alkoxy group, most preferably a methoxy group or an ethoxy group. A is 0, 1 or 2. It is an integer of 0 or 1 is most preferable.)

The crosslinkable silyl group can be introduced into the main chain, specifically, for example, by the following known method.
(A) An organic compound (for example, allyl isocyanate) having an active group and an unsaturated group that are reactive with this functional group in a polyoxyalkylene-based or vinyl-based polymer having a functional group such as a hydroxyl group at the terminal. The reaction product is then hydrosilylated by allowing hydrosilane having a hydrolyzable group to act on the obtained reaction product.
(B) A compound having a functional group and a crosslinkable silyl group that are reactive with this functional group in a polyoxyalkylene-based or vinyl-based polymer having a functional group such as a hydroxyl group, an epoxy group or an isocyanate group at the terminal. How to react.
Examples of the compound having a reactive functional group and a crosslinkable silyl group include amino group-containing silanes, mercapto group-containing silanes, epoxy group-containing silanes, vinyl-type unsaturated group-containing silanes, chlorine atom-containing silanes, and isocyanates. Examples include group-containing silanes and hydrosilanes.
(C) Compounds having a polymerizable unsaturated bond and a crosslinkable silyl group (for example, CH ₂ = CHSi (OCH ₃ ) ₃ or CH ₂ = CHCOO (CH ₂ ) ₂ Si (OCH ₃ ) ₃ ) and (meth) acrylic A method of copolymerizing with an acid alkyl ester monomer.
(D) A compound having a polymerizable unsaturated bond and a functional group (for example, hydroxyethyl (meth) acrylate or allyl (meth) acrylate) is added to the (meth) acrylic acid alkyl ester monomer and copolymerized. then compound the copolymer produced with a reactive functional group and a crosslinking silyl group of the (for example, a compound having an isocyanate group and -Si (OCH _{3) 3} group, trimethoxysilane, hydrolysis, such as triethoxy silane A method of reacting with hydrosilanes having a degradable group.

In the present invention, the number average molecular weight of the silicone resin and the modified silicone resin is preferably 1,000 or more, and particularly preferably 6,000 to 30,000. Further, when the molecular weight distribution is narrow, the viscosity of the curable composition is low, and the rubber physical properties such as strength, elongation and modulus after curing are excellent, which is preferable.

A compound having a nitroxide radical having a number average molecular weight of 2,000 or more (hereinafter, may be simply referred to as a “compound having a nitroxide radical”) will be described. A compound having a nitroxide radical is a compound having at least one or more nitroxide radicals in the compound and having a number average molecular weight of 2,000 or more. By blending this compound with a curable composition containing a room temperature curable resin, the viscosity of the curable composition can be reduced and workability when using the curable composition can be improved. Further, the curable composition containing a compound having a nitroxide free radical is less likely to bleed from the cured product after curing, so that surface contamination is less likely to occur and the rubber physical characteristics are less likely to be hardened. Further, it imparts weather resistance for a long period of time without impairing the rocking denaturation of the curable composition. The number average molecular weight of the compound having a nitroxide radical is preferably 2,000 or more, more preferably 2,000 to 30,000, and particularly preferably 2,000 to 20,000.

The compound having a nitroxide radical is a group represented by the following general formula (1).

Examples of the compound having a nitroxide free radical include a polyoxyalkylene compound having a nitroxide free radical having a number average molecular weight of 2,000 or more, and a poly (meth) acrylic compound having a number average molecular weight of 2,000 or more. These compounds have good compatibility with room temperature curable resins and tend to be difficult to bleed after curing of the curable composition. All of these can be used alone or in combination of two or more.

A polyoxyalkylene compound having a nitroxide free group having a number average molecular weight of 2,000 or more has one or more nitroxide free groups in the compound, and the main chains thereof are (poly) oxyethylene and (poly) oxypropylene. , (Poly) oxyethylene propylene, (poly) oxybutylene and the like are polyoxyalkylene compounds.

A poly (meth) acrylic compound having a nitroxide free radical having a number average molecular weight of 2,000 or more is a compound having one or more nitroxide free radicals in the compound and the main chain thereof being a (meth) acrylic acid ester. Is.

The "system" of a polyoxyalkylene compound having a nitroxide free radical is 50% by mass or more of the portion of the compound excluding the nitroxide radical, and if 80% by mass or more is composed of polyoxyalkylene, the rest. It means that the portion may be modified with ester, urethane or the like. Further, the "system" of the poly (meth) acrylic compound having a nitroxide free radical is composed of 50% by mass or more, and further 80% by mass or more of the portion of the compound excluding the nitroxide free radical is a (meth) acrylic acid ester. If so, it means that the remaining portion may be modified with urethane or the like.

Specific examples of the method for producing a polyoxyalkylene compound having a nitroxide free radical include an organic isocyanate compound in a reaction vessel made of glass or stainless steel, and a polyoxyalkylene alcohol (polyoxyalkylene polyol and / or). Polyoxyalkylene-based monool) and an active hydrogen-containing compound having a nitroxide radical are charged all at once or sequentially, and while stirring at 50 to 120 ° C. in the presence or absence of a reaction catalyst or an organic solvent. Examples include a method of reacting. At this time, when the isocyanate group reacts with water such as moisture, the polyoxyalkylene compound having a nitrogen free group thickens. Therefore, the inside of the container should be replaced with nitrogen gas in advance or the reaction should be carried out under a nitrogen gas stream. Is preferable. The molar ratio of the total active hydrogen (group) of the isocyanate group of the organic isocyanate compound to the active hydrogen-containing compound having a polyoxyalkylene alcohol (polyoxyalkylene polyol and / or polyoxyalkylene monool) and a nitroxide free group. The (isocyanate group / active hydrogen) is preferably 0.9 to 1.1, more preferably 0.95 to 1.05, and particularly preferably 1.0.

Specific examples of the method for producing a poly (meth) acrylic compound having a nitroxide free group include an organic isocyanate compound in a reaction vessel made of glass or stainless steel, and a hydroxyl group-containing poly (meth) acrylic polymer (poly (meth) acrylic polymer. ) Acrylic polyol and / or poly (meth) acrylic monool) and an active hydrogen-containing compound having a nitroxide free group are charged in a batch or sequentially, and 50 in the presence or absence of a reaction catalyst or an organic solvent. Examples thereof include a method of reacting with stirring at ~ 120 ° C. At this time, when the isocyanate group reacts with water such as moisture, the poly (meth) acrylic compound having a nitrogen free group thickens, so the inside of the container is replaced with nitrogen gas in advance or the reaction is carried out under a nitrogen gas stream. It is preferable to do so. The total active hydrogen of the isocyanate group of the organic isocyanate compound and the active hydrogen-containing compound having a hydroxyl group-containing poly (meth) acrylic polymer (poly (meth) acrylic polyol and / or poly (meth) acrylic monool) and a nitroxide free group. The molar ratio (isocyanate group / active hydrogen) of the group) is preferably 0.9 to 1.1, more preferably 0.95 to 1.05, and particularly preferably 1.0.

In the production of the above-mentioned polyoxyalkylene compound having a nitroxide free radical and the poly (meth) acrylic compound having a nitroxide free radical, a small amount of active hydrogen-containing functional group (for example, hydroxyl group) or isocyanate group can be produced by selecting the molar ratio. It may remain in the molecule, but in this case it can be considered that it does not have in order to achieve the object of the present invention. The "small amount" means that the amount of active hydrogen-containing functional group or isocyanate group remaining in the molecule is 1 g of a polyoxyalkylene compound having a nitroxide free radical or a poly (meth) acrylic compound having a nitroxide free radical. The hit is preferably 0.05 mmol or less, more preferably 0.02 mmol or less.

The organic isocyanate compound used for producing the polyoxyalkylene compound having a nitroxide free group and the poly (meth) acrylic compound having a nitroxide free group is the organic polyisocyanate used for producing the urethane prepolymer described above, or organic. Monoisocyanate can be used. As the organic polyisocyanate, an aliphatic polyisocyanate, an aromatic aliphatic polyisocyanate, an alicyclic polyisocyanate, and a modified isocyanate obtained by modifying these organic polyisocyanates are preferable in that the effect of imparting weather resistance is high. Further, as the organic monoisocyanate, an aliphatic monoisocyanate is preferable. All of these can be used alone or in combination of two or more.

Examples of the polyoxyalkylene alcohol used in producing the polyoxyalkylene compound having a nitroxide free radical include a polyoxyalkylene-based polyol and a polyoxyalkylene-based mono that can be used in producing the above-mentioned urethane prepolymer. All can be mentioned. All of these can be used alone or in combination of two.

The total degree of unsaturation of the polyoxyalkylene-based polyol and the polyoxyalkylene-based monool is preferably 0.1 meq / g or less, more preferably 0.07 meq / g or less, and particularly preferably 0.04 meq / g or less. In addition, the molecular weight distribution of polyoxyalkylene-based polyols and polyoxyalkylene-based monools [ratio of polystyrene-equivalent weight average molecular weight (Mw) to number average molecular weight (Mn) by gel permeation chromatography (GPC) = Mw / Mn ] Is preferably 1.6 or less, and particularly preferably 1 to 1.3 polyoxyalkylene-based polyols. By setting the total degree of unsaturation and the molecular weight distribution of the polyoxyalkylene-based polyol and the polyoxyalkylene-based monool within the above ranges, the viscosity of the polyoxyalkylene-based compound having a nitroxide free radical can be reduced, and the curable composition can be obtained. Increases the viscosity-reducing effect when blended. In addition, the rubber physical properties of the curable composition after curing tend to be low modulus and high elongation.

Examples of the hydroxyl group-containing (meth) acrylic polymer for producing a poly (meth) acrylic compound having a nitroxide free radical include a poly (meth) acrylic polyol that can be used for producing the above-mentioned urethane prepolymer. Be done.

The active hydrogen-containing compound having a nitroxide radical is preferably an active hydrogen-containing compound having a piperidine ring in which the nitroxide radical is chemically stable at room temperature in the presence of oxygen.

Examples of the active hydrogen-containing compound having a nitroxide free radical include an active hydrogen-containing compound having a 2,2,6,6-substituted piperidine1-oxy radical and a 2,2,5,5-substituted piperidine 1-oxy free radical. Active hydrogen-containing compounds having a nitroxide radical derived from cyclic hydroxyamine, such as active hydrogen-containing compounds having, are preferable. As the substituent, an alkyl group having 4 or less carbon atoms, such as a methyl group or an ethyl group, is suitable. Examples of the active hydrogen-containing compound having a nitroxide radical derived from cyclic hydroxyamine include a compound represented by the following general formula (2).

（式中、Ｒ^１〜Ｒ^６はそれぞれ独立に水素原子または炭素数１〜４のアルキル基を表し、Ｘ^１およびＸ^２はヒドロキシ基（−ＯＨ）、アミノ基（ＮＨ_２）または水素原子を表す。ただし、Ｘ^１およびＸ^２のいずれかは、ヒドロキシ基またはアミノ基である。）

(In the formula, R ^{1 to} R ⁶ independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X ¹ and X ² represent a hydroxy group (-OH), an amino group (NH ₂ ) or a hydrogen atom. However, ^{either X 1} or X ² is a hydroxy group or an amino group.)

Specific examples of the active hydrogen-containing compound having a nitroxide radical include 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl and 4-hydroxy-2,2,6,6-tetraethylpiperidine. 1-oxyl, 4-amino-2,2,6,6-tetramethylpiperidin 1-oxyl, 4-amino-2,2,6,6-tetraethylpiperidin 1-oxyl, 3-hydroxy-2,2,5 , 5-Tetramethylpiperidin 1-oxyl, 3-hydroxy-2,2,5,5-tetraethylpiperidine1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidin 1-oxyl, 3-amino −2,2,5,5-tetraethylpyrrolidin 1-oxyl can be mentioned. All of these can be used alone or in combination of two or more. Of these, 4-hydroxy-2,2,6,6-tetramethylpiperidin1-oxyl is preferable because of its availability.

The blending amount of the polyoxyalkylene compound having a nitroxide radical is preferably 5 to 150 parts by mass, more preferably 5 to 100 parts by mass with respect to 100 parts by mass of the room temperature curable resin.

The curable composition of the present invention can further contain a block amine compound. The blockamine compound is a compound in which active hydrogen bonded to a nitrogen atom of a compound having a primary and / or secondary amino group is dehydrated and blocked with a compound having a carbonyl group such as a ketone or an aldehyde.

Specific examples of the blockamine compound include an oxazolidine compound which is a reaction product of an amino alcohol and a carbonyl compound.

The oxazolidine compound is a compound having one or more, preferably 1 to 6 oxazolidine rings, which are heterocycles of saturated 5-membered rings containing oxygen atoms and nitrogen atoms, in the molecule. When an oxazolidine compound is blended with an isocyanate group-containing resin which is a room temperature curable resin, it functions as a latent curing agent. More specifically, when the isocyanate group of the isocyanate group-containing resin reacts with water, it forms a urea bond and cures. At this time, carbon dioxide gas is also generated and bubbles due to carbon dioxide gas are generated in the cured product to cure. Problems such as deterioration of the appearance of the object, breakage, and deterioration of adhesiveness may occur. In addition, the oxazolidine compound reacts with water and is hydrolyzed, and the oxazolidine ring produces (regenerates) a secondary amino group and an alcoholic hydroxyl group. On the other hand, when an isocyanate group-containing resin containing an oxazolidine compound is reacted with water, the water reacts preferentially with the oxazolidine compound, and the oxazolidine ring of the oxazolidine compound is a secondary amino group and an alcoholic hydroxyl group (active). Hydrogen group) is generated. Next, the generated active hydrogen group (particularly the secondary amino group) reacts preferentially with the isocyanate group, so that the generation of carbon dioxide gas due to the reaction between water and the isocyanate group is suppressed, and the curable composition foams during curing. Can be prevented.

Examples of the oxazolidine compound include a urethane bond-containing oxazolidine compound, an ester group-containing oxazolidine compound, an oxazolidine silyl ether compound, and a carbonate group-containing oxazolidine compound. These oxazolidine compounds can be obtained by reacting the hydroxyl group of a compound having a hydroxyl group and an oxazolidine ring with the isocyanate group of an organic polyisocyanate compound or the carboxyl group of an organic carboxylic acid compound. Of these oxazolidine compounds, urethane bond-containing oxazolidine compounds are preferable because they are easy to produce.

Specific examples of the compound having a hydroxyl group and an oxazolidine ring include N-hydroxyalkyloxazolidine obtained by a dehydration condensation reaction between a secondary amino group of an alkanolamine and a carbonyl group of a ketone compound or an aldehyde compound. As a method for producing the compound having a hydroxyl group and an oxazolidine ring, 1 mol or more, preferably 1 to 1.5 mol, more preferably 1 mol, preferably 1 to 1.5 mol of the carbonyl group of the aldehyde compound or the ketone compound is made with respect to 1 mol of the secondary amino group of the alkanolamine. Is used, and a method of performing a dehydration condensation reaction while heating and refluxing in a solvent such as toluene or xylene to remove by-produced water can be mentioned. Excess aldehyde compounds and ketone compounds may be removed by distillation.

Examples of alkanolamines include diethanolamine, dipropanolamine, and N- (2-hydroxyethyl) -N- (2-hydroxypropyl) amine. Examples of the ketone compound include acetone, diethyl ketone, isopropyl ketone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, methyl-tert-butyl ketone, diisobutyl ketone, cyclopentanone and cyclohexanone. Examples of the aldehyde compound include acetaldehyde, propionaldehyde, n-butylaldehyde, isobutylaldehyde, barrelaldehyde, isobarrelaldehyde, 2-methylbutylaldehyde, n-hexylaldehyde, 2-methylpentylaldehyde, n-octylaldehyde, 3,5. , 5-Trimethylhexyl aldehyde and other aliphatic aldehyde compounds; examples thereof include aromatic aldehyde compounds such as benzaldehyde, methyl benzaldehyde, trimethyl benzaldehyde, ethyl benzaldehyde, isopropyl benzaldehyde, isobutyl benzaldehyde, methoxy benzaldehyde, dimethoxy benzaldehyde and trimethoxy benzaldehyde. All of these can be used alone or in combination of two or more.

Of these, diethanolamine is preferable as the alkanolamine, and the ketone compound or the aldehyde compound is preferable because it is easy to produce a compound having a hydroxyl group and an oxazolidine ring and is excellent in preventing foaming when the curable composition is cured. Of these, aldehyde compounds are preferable, and isobutylaldehyde, 2-methylpentylaldehyde, and benzaldehyde are more preferable.

Specific examples of compounds having a hydroxyl group and an oxazolidine ring include 2-isopropyl-3- (2-hydroxyethyl) oxazolidine, 2- (1-methylbutyl) -3- (2-hydroxyethyl) oxazolidine, and 2-phenyl-. Examples thereof include 3- (2-hydroxyethyl) oxazolidine.

As the urethane bond-containing oxazolidine compound, the molar ratio of isocyanate group / hydroxyl group of the isocyanate group of the organic polyisocyanate compound and the hydroxyl group and the hydroxyl group of the compound having an oxazolidine ring is 0.9 / 1 to 1.2 / 1, preferably 0. Examples thereof include those obtained by reacting at a temperature of 50 to 120 ° C. in the presence or absence of an organic solvent, which is used so as to be .95 / 1 to 1.05 / 1.

Examples of the organic polyisocyanate compound used for producing the urethane bond-containing oxazolidine compound include the same as those used for producing the urethane prepolymer described above. Of these, aromatic aliphatic polyisocyanates and aliphatic polyisocyanates are preferable, and xylylene diisocyanate and hexamethylene diisocyanate are particularly preferable.

The ester group-containing oxazolidine compound can be obtained by reacting the above-mentioned compound having a hydroxyl group and an oxazolidine ring with a lower alkyl ester of a dicarboxylic acid or a polycarboxylic acid.

The oxazolidine silyl ether compound includes the above-mentioned compound having a hydroxyl group and an oxazolidine ring, trimethoxysilane, tetramethoxysilane, triethoxysilane, dimethoxydimethylsilane, vinyltrimethoxysilane, vinyltriethoxysilane, and 3-glycidoxypropyltri. It is obtained by a dealcohol reaction with an alkoxysilane such as methoxysilane and 3-glycidoxypropyltriethoxysilane.

The carbonate group-containing oxazolidine compound can be obtained by reacting the above-mentioned compound having a hydroxyl group and an oxazolidine ring with a carbonate such as diallyl carbonate using a polyhydric alcohol such as diethylene glycol or glycerin.

All of these oxazolidine compounds can be used alone or in combination of two or more.

The oxazolidine compound preferably does not have an active hydrogen-containing functional group such as an amino group or a hydroxyl group that reacts with the isocyanate group of the isocyanate group-containing resin at room temperature, or an isocyanate group. This is to prevent an increase in the viscosity of the isocyanate group-containing resin and a decrease in the foaming prevention performance of the oxazolidine compound. However, in the production of the above-mentioned urethane bond-containing oxazolidine compound, a small amount of active hydrogen-containing functional group or isocyanate group may remain in the molecule depending on the selection of the molar ratio. In this case, in order to achieve the object of the present invention. It can be considered that it does not have. The "small amount" means that the amount of the active hydrogen-containing functional group or isocyanate group remaining in the molecule is preferably 0.05 mmol or less, more preferably 0.02 mmol or less per 1 g of the oxazolidine compound.

When an oxazolidine compound is used, the blending amount is 0.1 to 1 mol of active hydrogen of a secondary amino group produced (regenerated) by hydrolysis of the oxazolidine compound with respect to 1 mol of the isocyanate group of the isocyanate group-containing resin. It is preferable to blend so as to be 0.3 to 1 mol, and more preferably to blend so as to be 0.3 to 1 mol. If the amount of active hydrogen of the secondary amino group produced (regenerated) by hydrolysis of the oxazolidine compound is less than 0.1 mol, foaming prevention is insufficient, which is not preferable.

In the curable composition of the present invention, various additives can be added as needed in addition to the above-mentioned components as long as the object of the present invention is not impaired. Additives are added to the curable composition and used to improve various performances such as viscosity adjustment, curing acceleration, and adhesiveness of the curable composition. Specific examples thereof include a curing accelerator, a plasticizer, a weather-resistant stabilizer, a filler, a rocking denaturing agent, an adhesiveness improving agent, a storage stability improving agent (dehydrating agent), a coloring agent, and an organic solvent. All of these can be used alone or in combination of two or more.

The curing acceleration catalyst is used to promote cross-linking curing of a room temperature curable resin by reacting with an active hydrogen-containing compound (for example, water such as humidity). Further, the curing acceleration catalyst can also be used as a reaction catalyst at the time of producing the above-mentioned urethane prepolymer and polyoxyalkylene compound having a nitroxide free radical. When used as a reaction catalyst during the production of a urethane prepolymer or a polyoxyalkylene compound having a nitroxide radical, the reaction catalyst remaining in the urethane prepolymer or the polyoxyalkylene compound having a nitroxide radical is curable. It may also act as a curing accelerator for the composition.

Specific examples of the curing acceleration catalyst include metal-based catalysts and amine-based catalysts.

Examples of the metal-based catalyst include a salt of a metal and an organic acid, a salt of an organic metal and an organic acid, and a metal chelate compound. Examples of the salt of the metal and the organic acid include salts of various metals such as tin, bismuth, zirconium, zinc and manganese and organic acids such as octyl acid, neodecanoic acid, stearic acid and naphthenic acid. Specific examples thereof include tin octylate, tin naphthenate, bismuth octylate, and zirconium octylate. Salts of organic metals and organic acids include dibutyltin dioctate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dimaleate, dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversate, dibutyltin oxide and phthalates. Things can be mentioned. Examples of the metal chelate compound include dibutyltin bis (acetylacetonet), EXCESTAR C-501 manufactured by Asahi Glass Co., Ltd., which is a tin-based chelate compound, zirconium tetrakis (acetylacetonate), titanium tetrakis (acetylacetoneate), and aluminum tris (acetylacetone). Nart), aluminum tris (ethylacetacetate), acetylacetone cobalt, acetylacetone iron, acetylacetone copper, acetylacetone magnesium, acetylacetone bismuth, acetylacetone nickel, acetylacetone zinc, acetylacetone manganese.

Examples of amine-based catalysts include tertiary amines. Examples of tertiary amines include triethylamine, tributylamine, triethylenediamine, hexamethylenetetramine, 1,8-diazabicyclo [5,4,0] undecene-7 (DBU), 1,4-diazabicyclo [2,2,2]. Examples include octane (DABCO) and salts of these tertiary amines and organic carboxylic acids.

Any of these curing acceleration catalysts can be used alone or in combination of two or more.

Of these, salts of metals and organic acids, salts of organic metals and organic acids, and metal chelate compounds are preferable, and salts of tin and organic acids, and bismuth, because the curable composition is excellent in curability. Salts with organic acids, salts with organic tin and organic acids, salts with organic bismuth and organic acids, tin chelate compounds, and bismuth chelate compounds are preferred.

The amount of the curing acceleration catalyst used is preferably 0.005 to 5 parts by mass, particularly preferably 0.005 to 2 parts by mass with respect to 100 parts by mass of the room temperature curable resin.

The plasticizer is used for the purpose of lowering the viscosity of the curable composition to improve workability and adjusting the physical characteristics of the rubber after curing of the curable composition. Specifically, phthalates such as dioctyl phthalate, diisononyl phthalate, dibutyl phthalate, and butyl benzyl phthalate; aliphatic carboxylic acid esters such as dioctyl adipate, diisodecyl succinate, dibutyl sevacinate, and butyl oleate. Kind.

The plasticizer is preferably used in an amount of 1 to 200 parts by mass, more preferably 2 to 50 parts by mass, based on 100 parts by mass of the room temperature curable resin.

The weather-resistant stabilizer is used for the purpose of preventing oxidation, photodegradation, and heat deterioration of the curable composition to further improve weather resistance and heat resistance. Examples of the weather resistance stabilizer include a hindered amine-based light stabilizer, a hindered phenol-based antioxidant, and an ultraviolet absorber. All of these weather-resistant stabilizers can be used alone or in combination of two or more.

As hindered amine-based light stabilizers, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis decanoate (2,2,6,6-tetramethyl-1 (octyloxy) -4 -Piperidyl) ester, bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] butylmalonate, Methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- [3- (3,3) 5-Di-tert-Butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6 6-Tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, dimethyl 1- (2-hydroxyethyl) succinate-4-hydroxy-2,2,6,6-tetramethyl Piperidine polycondensate, poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetra) Methyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}], N, N'-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-Butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, as well as ADEKA's Adecastab LA- Examples thereof include 63P and LA-68LD.

As hindered phenolic antioxidants, 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-hydroxyphenyl) propioamide], benzenepropanoic acid 3,5-bis Examples thereof include (1,1-dimethylethyl) -4-hydroxy C7-C9 side chain alkyl ester and 2,4-dimethyl-6- (1-methylpentadecyl) phenol.

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

Of these, hindered amine-based photostabilizers and hindered phenol-based antioxidants are preferable because they are highly effective in improving weather resistance. The weather resistance stabilizer is preferably used in an amount of 0.01 to 30 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the room temperature curable resin.

The filler is used for the purpose of increasing the amount of the curable composition and reinforcing the physical properties of the cured product. Specifically, mica, kaolin, zeolite, graphite, diatomaceous earth, clay, clay, talc, slate powder, silicic anhydride, quartz fine powder, aluminum powder, zinc powder, synthetic silica such as precipitated silica, calcium carbonate, carbon dioxide. Inorganic powder fillers such as magnesium, alumina, calcium oxide, magnesium oxide; fibrous fillers such as glass fibers and carbon fibers; inorganic balloon fillers such as glass balloons, talc balloons, silica balloons and ceramic balloons; wood Powder, walnut shell powder, rice husk powder, pulp powder, cotton chips, rubber powder, fine powder of thermoplastic or thermosetting resin, powder such as polyethylene or hollow body, organic balloon-like filling such as Saran microballoon; etc. , Flame-retardant fillers such as magnesium hydroxide and aluminum hydroxide can also be mentioned. The particle size of the filler is preferably 0.01 to 1,000 μm.

The rock denaturing agent is used for the purpose of preventing sagging (slump) of the curable composition. Specific examples thereof include inorganic shake denaturing agents such as fine powder silica and fatty acid-treated calcium carbonate; and organic shaking denaturing agents such as organic bentonite and fatty acid amide. All of these can be used alone or in combination of two or more. A compound having a nitroxide free radical having a number average molecular weight of 2,000 or more is unlikely to inhibit the effect of these rock denaturing agents. In particular, it is difficult to inhibit the effect of imparting shaking modification of fine powdered silica.

Examples of the fine powder silica include hydrophilic silica and hydrophobic silica. All of these can be used alone or in combination of two or more.

Examples of the hydrophilic silica include natural silica obtained by finely pulverizing quartz, silica sand and the like, and synthetic silica such as dry silica and wet silica. Dry silica is obtained by burning a silane gas such as silicon tetrachloride in an oxyhydrogen flame, and is sometimes referred to as fumed silica. In addition, wet silica includes precipitation-type silica in which silica is precipitated in a solution by neutralizing sodium silicate with a mineral acid, and is sometimes referred to as white carbon.

Examples of the hydrophobic silica include those which have been made hydrophobic by surface-treating the hydrophilic silica with an organosilicon compound having reactivity with the hydrophilic silica.

Fatty acid surface-treated calcium carbonate is obtained by treating the surface of heavy calcium carbonate, light calcium carbonate, and colloidal calcium carbonate with fatty acids such as fatty acids, fatty acid alkyl esters, fatty acid metal salts, and fatty acid organic salts. Examples of the fatty acid include fatty acids having a carbonic acid number of 10 to 25 such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and hebenic acid. Examples of the metal salt include sodium salt, potassium salt, calcium salt, aluminum salt, and examples of the organic salt include ammonium salt.

The amount of the rock denaturing agent used is preferably 1 to 200 parts by mass, more preferably 5 to 150 parts by mass with respect to 100 parts by mass of the room temperature curable resin.

The adhesiveness improver is used for the purpose of improving the adhesiveness of the curable composition. Specific examples thereof include various coupling agents such as silane-based, aluminum-based, and zircoaluminate-based, or partial hydrolysis condensates thereof. Of these, a silane coupling agent or a partially hydrolyzed condensate thereof is preferable because it has excellent adhesiveness.

Examples of the silane coupling agent include vinyltrimethoxysilane, vinylmethyldimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, and 3-mercaptopropyltrimethoxysilane. 3-Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) Examples thereof include compounds having an alkoxysilyl group of -3-aminopropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane and the like and having a molecular weight of 500 or less. Alternatively, a compound having a molecular weight of 200 to 3,000 as a partially hydrolyzed condensate of one or more of these silane coupling agents can be mentioned. All of these can be used alone or in combination of two or more.

The storage stability improver (dehydrating agent) is used for the purpose of improving the storage stability of the curable composition. Specific examples thereof include vinyltrimethoxysilane, calcium oxide, and p-toluenesulfonyl isocyanate (PTSI), which react with water present in the curable composition and act as a dehydrating agent. All of these can be used alone or in combination of two or more.

The colorant is used for the purpose of coloring the curable composition and imparting design to the cured product. Specific examples thereof include inorganic pigments such as titanium oxide and iron oxide, organic pigments such as copper phthalocyanine, and carbon black. All of these can be used alone or in combination of two or more.

The organic solvent is used for the purpose of lowering the viscosity of the curable composition and improving the extrudability and workability at the time of casting and coating. The organic solvent can be used without particular limitation as long as it has good compatibility with other components in the curable composition and does not react with other components. Specifically, carbonate solvents such as dimethyl carbonate, ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate and butyl acetate, aliphatic solvents such as n-hexane, and alicyclic solvents such as cyclohexane. Examples thereof include solvents, aromatic solvents such as toluene and xylene, and organic solvents such as petroleum distillate solvents such as mineral spirit and industrial gasoline. All of these can be used alone or in combination of two or more. These organic solvents may be used in the synthesis of urethane prepolymers, in the synthesis of compounds having nitroxide radicals, or in the preparation of curable compositions.

Since the curable composition of the present invention reacts with an active hydrogen-containing compound (for example, water such as moisture) and is crosslinked and cured, it can be used as a one-component moisture-curable composition. Further, a room temperature curable resin in the present invention is used as a main component, and a curing agent or a compound having a nitroxide radical having a number average molecular weight of 2,000 or more is blended therein to prepare a two-component (multi-component) reaction-curable composition. Can also be used.

When used as a two-component reaction-curable composition, when an isocyanate group-containing resin is used as the main agent at room temperature curable resin, an active hydrogen-containing compound such as polyol or polyamine can be used as the curing agent. Examples of the active hydrogen-containing compound such as polyol and polyamine used as a curing agent include active hydrogen-containing compounds (for example, high molecular weight polyol and high molecular weight polyamine) that can be used when synthesizing an isocyanate group-containing urethane prepolymer.
In the two-component reaction-curable composition, the reaction molar ratio (isocyanate group / active hydrogen) of the isocyanate group of the isocyanate group-containing resin as the main agent and the active hydrogen (group) of the active hydrogen compound such as polyol or polyamine as the curing agent is , 0.9 to 1.3 is preferable, and further 1 to 1.2 is preferable.

Further, when a crosslinkable silyl group-containing resin is used as the room temperature curable resin as the main agent, a curing acceleration catalyst can be used as the curing agent. Examples of the curing acceleration catalyst used in the curing agent include the above-mentioned metal-based catalysts and amine-based catalysts, and metal-based catalysts are particularly preferable.

The compound having an average number of 2,000 or more nitroxide radicals to be blended in the two-component reaction-curable composition may be blended in the main agent in advance or blended in the curing agent. Further, when mixing the main agent and the curing agent, a predetermined amount may be blended and mixed together with the main agent and the curing agent.

Even when used as a two-component reaction-curable composition, a blockamine compound or an additive is blended in addition to the above-mentioned room temperature curable resin, a compound having a nitroxide free radical of 2,000 or more on average, and a curing agent. be able to. Examples of the blockamine compound and the additive include the above-mentioned blockamine compound and the additive. The blockamine compound and the additive may be blended in the main agent in advance or may be blended in the curing agent. Further, when mixing the main agent and the curing agent, a predetermined amount may be blended and mixed together with the main agent and the curing agent.

As a mixing method of the two-component reaction-curable composition, there is a method of uniformly mixing each component using a mixer such as a hand mixer, a vacuum defoaming mixer, or a drum rotary mixer.

When the curable composition of the present invention is used, the materials (members) to be constructed include mortar, concrete, ALC (Autoclaved Lightweight Concrete), glass, marble, mikage stone, siding, tile, roof tile, and brick. Inorganic materials such as iron, copper, stainless steel, galvanium steel plate, totan, aluminum, titanium and other metal materials, acrylic resin, polyester resin, vinyl chloride, ABS (Acrylonitrile-Butadiene-Styrene copolymer), FRP (Fiber Reinforced Plastic), etc. Materials made of synthetic resin; wood-based materials such as wood and plywood can be mentioned.

The method for producing the curable composition of the present invention is not particularly limited in the case of a one-component moisture-curable composition, but specifically, a room temperature curable resin and a nitroxide free radical having a number average molecular weight of 2,000 or more. Compounds with radicals, and if necessary, block amine compounds and additives are placed in a mixing (kneading) container made of glass, stainless steel, iron, etc. with a stirrer to block water such as moisture, and batched under a dry nitrogen stream. Examples thereof include a method of stirring and mixing in a formula or continuous manner. In the case of a two-component reaction type curable composition, each component of the main agent and the curing agent is individually charged in a mixing (kneading) container equipped with a stirrer to block water such as moisture, and a batch type or a batch type under a dry nitrogen stream. Examples thereof include a method of continuously stirring and mixing for production.

When the curable composition of the present invention is used as a one-component moisture-curable composition, the room-temperature curable resin reacts with water such as moisture to thicken and cure, so that a container capable of blocking water such as moisture. It is preferable to pack it in a container and store it in a sealed manner. The container is not particularly limited as long as it can block water such as humidity. Specific examples thereof include metal and resin pail cans, aluminum bags, and paper and resin cartridges. Even when it is used as a two-component reaction type curable composition, it is preferable to pack each component such as a main agent and a curing agent in a container capable of blocking water such as moisture and store it in a sealed container.

Examples of the present invention are shown below, but the present invention is not construed as being limited to the examples.

Synthesis Example 1 (Synthesis of isocyanate group-containing urethane prepolymer)
595.8 g of polyoxypropylene diol (manufactured by Asahi Glass Co., Ltd., product name EL-3021, hydroxyl value 34.68 mgKOH / g) while flowing nitrogen gas through a stirrer, thermometer, nitrogen introduction tube and reaction vessel equipped with a heating / cooling device. , Polyoxypropylene triol (manufactured by Asahi Glass Co., Ltd., product name EL-4030, hydroxyl value 41.47 mgKOH / g) 175.2 g, organic solvent (manufactured by JX Nikko Nisseki Energy Co., Ltd., product name Cactus Solvent P-20) 157 Add 71.2 g of xylylene diisocyanate (manufactured by Mitsui Chemicals Co., Ltd., product name: Takenate 500) and 0.1 g of dibutyltin dilaurate as a reaction catalyst, and react at 70-80 ° C for 2 hours with heating. The reaction was terminated when the isocyanate group content became the theoretical value (1.09% by mass) or less to obtain an isocyanate group-containing urethane prepolymer. The viscosity of the isocyanate group-containing urethane prepolymer at 25 ° C. is 3,800 mPa · s, and the isocyanate group content actually measured by titration is 1.06% by mass (the isocyanate group content of the isocyanate group-containing urethane prepolymer after subtracting the solvent content is It was 1.26% by mass). The number average molecular weight of the isocyanate group-containing urethane prepolymer was 3,600 in terms of polystyrene as measured by gel permeation chromatography (GPC).

Synthesis Example 2 (Synthesis of isocyanate group-containing urethane prepolymer)
409.0 g of polyoxypropylene diol (manufactured by Asahi Glass Co., Ltd., product name EL-3021, hydroxyl value 34.53 mgKOH / g) while flowing nitrogen gas through a stirrer, thermometer, nitrogen introduction tube and reaction vessel equipped with a heating / cooling device. , Polyoxypropylene triol (manufactured by Asahi Glass Co., Ltd., product name EL-4030, hydroxyl value 41.3 mgKOH / g) 379.3 g, pentaerythritol triacrylate 17.4 g, organic solvent (manufactured by JX Nikko Nisseki Energy Co., Ltd., product) Add 119.3 g of the famous Cactus Solvent P-20), add 74.9 g of xylylene diisocyanate (manufactured by Mitsui Chemicals, product name: Takenate 500), and 0.1 g of dibutyltin dilaurate as a reaction catalyst, and heat the mixture. The reaction was carried out at 70 to 80 ° C. for 2 hours, and when the isocyanate group content became the theoretical value (0.87% by mass) or less, the reaction was terminated to obtain an isocyanate group-containing urethane prepolymer.

Synthesis Example 3 (Synthesis of polyoxyalkylene compound having nitroxide radical)
Polyoxypropylene diol (manufactured by Asahi Glass Co., Ltd., product name PML-4001, hydroxyl value 56.39 mgKOH / g, total degree of unsaturation) while flowing nitrogen gas through a stirrer, thermometer, nitrogen introduction tube and reaction vessel with heating / cooling device. Add 277.8 g of 0.008 meq / g), add 62.0 g of isophorone diisocyanate (manufactured by Ebonic Japan) while stirring, add 0.1 g of dibutyltin dilaurate as a reaction catalyst, and heat to 2 at 70-80 ° C. After a time reaction, the mixture was cooled to 30 ° C. or lower when the isocyanate group content was below the theoretical value. Next, a solution prepared by dissolving 48.0 g of 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (manufactured by Wako Pure Chemical Industries, Ltd.) in 112.1 g of dimethyl carbonate was charged and heated. After reacting at 70 to 80 ° C. for 4 hours and confirming the disappearance of the peak of the isocyanate group by FT-IR, the mixture was cooled to 30 ° C. or lower to obtain a polyoxyalkylene compound having a nitroxide free group. The number average molecular weight of the polyoxyalkylene compound having a nitroxide free radical was 2,830 in terms of polystyrene as measured by gel permeation chromatography (GPC). The content (theoretical value) of the nitroxide free radical (NO.) In the polyoxyalkylene compound having a nitroxide free radical (excluding the solvent content) is 2.16% by mass.

Example 1
1000 g of the isocyanate group-containing urethane prepolymer of Synthesis Example 1 and 300 g of the polyoxyalkylene compound having a nitroxide free group of Synthesis Example 3 were charged into a kneading container equipped with a stirrer, a decompression device and a nitrogen introduction tube while flowing nitrogen gas. While stirring, 690 g of heavy calcium carbonate (manufactured by Shiraishi Calcium, product name Whiten B) and 70 g of organic solvent (manufactured by JX Nikko Niseki Energy Co., Ltd., product name Cactus Solvent P-20) were charged to make the contents uniform. Kneaded until it became. Next, 15 g of an antioxidant (manufactured by BASF, product name Irganox 245), 35 g of dimethyl carbonate as an organic solvent, 5 g of p-toluenesulfonyl isocyanate (PTSI), and fine powder silica (manufactured by Tokuyama Corporation, manufactured by Tokuyama Corporation) 64 g of product name Leoloseal QS-102S) was charged and kneaded until the contents became uniform. Further, defoaming was performed under reduced pressure at 20 to 50 hPa to prepare a curable composition (sealing material composition).

Example 2
1000 g of the isocyanate group-containing urethane prepolymer of Synthesis Example 2 and 300 g of the polyoxyalkylene compound having a nitroxide free group of Synthesis Example 3 were charged into a kneading container equipped with a stirrer, a decompression device and a nitrogen introduction tube while flowing nitrogen gas. While stirring, 600 g of heavy calcium carbonate (manufactured by Shiraishi Calcium, product name Whiten B) and 30 g of organic solvent (manufactured by JX Nikko Niseki Energy Co., Ltd., product name Cactus Solvent P-20) are charged to make the contents uniform. Kneaded until it became. Next, 15 g of an antioxidant (manufactured by BASF, product name Irganox 245), 30 g of dimethyl carbonate as an organic solvent, 5 g of p-toluenesulfonyl isocyanate (PTSI), and fine powder silica (manufactured by Tokuyama Corporation) as a denaturing agent. , Product name Leoloseal QS-102S) was charged and kneaded until the contents became uniform. Further, defoaming was performed under reduced pressure at 20 to 50 hPa to prepare a curable composition (sealing material composition).

Comparative Example 1
The same operation was carried out except that 11.8 g of a hindered amine light stabilizer (manufactured by BASF, product name TINUVIN292) was used instead of the polyoxyalkylene compound having a nitroxide radical in Example 1, and the curable composition was formed. A product (sealing material composition) was prepared.

Comparative Example 2
Same as in Example 1 except that 6.5 g of 2,2,6,6-tetramethylpiperidin 1-oxyl (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of the polyoxyalkylene compound having a nitroxide radical. To prepare a curable composition (sealing material composition).

Comparative Example 3
Same as in Example 1 except that 11.8 g of a hindered amine light stabilizer (manufactured by BASF, product name TINUVIN292) was used instead of the polyoxyalkylene compound having a nitroxide radical, and 350 g of dioctyl phthalate was used. To prepare a curable composition (sealing material composition).

Comparative Example 4
In Example 1, 6.5 g of 2,2,6,6-tetramethylpiperidine 1-oxyl (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of the polyoxyalkylene compound having a nitroxide radical, and dioctyl was further used. The same operation was carried out except that 350 g of phthalate was used to prepare a curable composition (sealing material composition).

Comparative Example 5
A curable composition (sealing material composition) was prepared by carrying out the same operation except that 350 g of dioctylphthalate was used instead of the polyoxyalkylene compound having a nitroxide free radical in Example 1.

Comparative Example 6
The same operation was carried out except that 11.8 g of a hindered amine light stabilizer (manufactured by BASF, product name TINUVIN292) was used instead of the polyoxyalkylene compound having a nitroxide radical in Example 2, and the curable composition was formed. A product (sealing material composition) was prepared.

<Evaluation of curable composition>
Extrudability, stain resistance, and weather resistance were evaluated using the curable compositions (sealing material compositions) of Example 1 and Comparative Examples 1 to 5. The evaluation results are shown in Table 1.

[Extrudability]
A curable composition (sealing material composition) was packed in a paper tube cartridge to prevent air from entering, sealed, left in an environment of 23 ° C. for 24 hours, and then the cartridge was extruded using a manual sealing gun. The extrudability was evaluated based on the following judgment based on the extruding situation.
◯: Contents can be easily extruded if extruded ×: Contents cannot be extruded unless extruded fairly strongly

[Pollutivity]
A joint having a width of 20 mm, a depth of 10 mm, and a length of 130 mm was prepared on a slate plate using strip-shaped slate pieces. The joint was filled with a curable composition (sealing material composition), the excess was scraped off with a spatula, and the test piece having a flat surface was cured in an environment of 23 ° C. and 50% RH for 7 days. Next, a water-based acrylic paint (Nippon Paint Co., Ltd., Nippetile crack, water-based top glossy first) was applied to the surface of the test piece, cured at 23 ° C. and 50% RH for 7 days, and then 5 in an incubator at 50 ° C. I left it for a day. Black silica sand (manufactured by Keimu Viewsera, product name 8 black) was sprinkled on the painted surface of the test piece taken out from the incubator, and immediately the test piece was turned over and the back side of the test piece was tapped by hand to remove excess black silica sand. .. The state of black silica sand (dirt) remaining on the painted surface was visually observed, and the contaminating property was evaluated by the following judgment.
◯: No black silica sand adhered to the painted surface or slight adhesion ×: A large amount of black silica sand adhered to the painted surface, and dirt was conspicuous.

[Weatherability]
A foamed polyethylene backup material having a thickness of 5 mm and a width of 12 mm was attached onto a slate plate having a thickness of 5 mm so as to form a square (frame) having a thickness of 5 mm, a width of 30 mm, and a length of 100 mm. A curable composition (sealing material composition) was cast in this frame, and the excess was scraped off with a spatula to flatten the surface. Then, it was cured in an environment of 23 ° C. and 50% RH for 14 days to prepare a test body (cured product).
The test piece was subjected to the WS-A method (Sunshine Weatherometer, Black Panel) of the exposure test method using the 6.3 open frame carbon arc lamp of JIS A 1415 (1999) "Exposure test method using a laboratory light source for polymer building materials". Visually observe changes in the appearance of the surface of each test piece after 1,000 hours, 2,000 hours, and 2,500 hours at a temperature of 63 ° C., after irradiation for 102 minutes, irradiation for 18 minutes, and water injection), and weather resistance. The sex was evaluated according to the following criteria.
Judgment criteria ○: No cracks on the surface of the test piece Δ: Fine cracks on the surface of the test piece ×: Many cracks on the surface of the test piece

<Evaluation of curable composition>
The tensile adhesiveness was evaluated using the curable composition (sealing material composition) of Example 2 and Comparative Example 6. The evaluation results are shown in Table 2.
[Tensile adhesiveness]
The tensile adhesiveness test (23 ° C.) was carried out by the 5.20 tensile adhesiveness test of JIS A 1439 (2010) “Test method for building sealant”. The adherend is a mortar, a one-component urethane primer (OP-2531, manufactured by Auto Chemical Industries, Ltd.) is applied to the adherend surface, dried and cured, and then a curable composition (sealing material composition) is applied. It was cast and cured to make a test body.

From the results in Table 1, it can be seen that the curable composition of Example 1 has good extrudability, excellent workability during use, and excellent stain prevention property of the top coat (coating film) on the surface of the cured product.
Further, in the weather resistance test, it can be seen that the curable composition of Example 1 has no cracks on the surface of the cured product even after 2,500 hours and has good weather resistance for a long period of time. On the other hand, in the curable composition using a hindered amine-based light stabilizer or the like, cracks were generated by the lapse of 2,500 hours.

From the results in Table 2, it can be seen that the curable composition of Example 2 has low modulus and high elongation in tensile adhesiveness (rubber physical characteristics) after curing.

As described above, the curable composition of the present invention is excellent in workability (extrusion property), stain prevention property, weather resistance, and rubber physical property (tensile adhesiveness), and is excellent in sealing material composition, waterproof material composition, and coating. It can be suitably used as a material composition. Further, the curable composition of the present invention can be suitably used for construction and civil engineering.

Claims (4)

It contains a room temperature curable resin and a compound having a nitroxide radical having a number average molecular weight of 2,000 or more.
The room temperature curable resin is an isocyanate group-containing resin or a crosslinkable silyl group-containing resin, and the compound having a nitroxide free group having a number average molecular weight of 2,000 or more is a polyoxyalkylene system having a nitroxide free group and a piperidine ring. A curable composition characterized by being a compound and / or a poly (meth) acrylic compound having a nitroxide radical and a piperidine ring. In addition, at least one or more selected from curing accelerators, plasticizers, weather stabilizers, fillers, rock denaturing agents, adhesion improvers, storage stability improvers (dehydrating agents), colorants and organic solvents. The curable composition according to claim 1 , wherein the curable composition contains an additive. The curable composition according to claim 1 or 2 , wherein the curable composition is a curable composition for construction or civil engineering. The curable composition according to any one of claims 1 to 3 , wherein the curable composition is a sealing material composition, a waterproof material composition, or a coating material composition.