JP6763160B2 - Walls with joint structure, joint construction method, and one-component room temperature moisture-curable sealant composition - Google Patents

Description

The present invention relates to a wall having a joint structure, a joint construction method, and a one-component room temperature moisture-curable sealant composition. In particular, the present invention relates to a wall having a joint structure of a structure such as a building, a joint construction method, and a one-component room temperature moisture-curable sealant composition.

Walls using ceramic siding boards or metal siding boards are widely used for the walls of structures such as buildings. In particular, the wall composed of ceramic siding boards is constructed by loading a backup material into the joints between adjacent ceramic siding boards, applying a primer to the side surfaces of the ceramic siding boards, and filling them with a sealing material. To. Conventionally, it is a joint structure of a ceramic siding board provided as an outer wall of a building, and a surface layer having a smooth surface and no air permeability on one side of a long base material made of synthetic resin foam. The joint structure of the ceramic siding board is known, in which the backup material formed in the above is loaded into the inner part of the joint so that the surface layer side faces the opening side of the joint, and the joint is further filled with a sealing material having low modulus. (See, for example, Patent Document 1). According to the joint structure of the ceramic siding board described in Patent Document 1, it is possible to prevent a semi-cylindrical or elliptical bulge that rises on the surface of the sealing material at the joint of a building with a simple structure.

Further, in the building sealing material, for example, a large elongation at break is required so as to cope with the expansion and contraction of the adherend such as the contraction of the ceramic siding board caused by the aging deterioration (see, for example, Non-Patent Document 1). .). Further, as described in Non-Patent Document 1, when the sealing material is used for a porous adherend, water, alkali, etc. ooze out from the inside of the porous adherend, so that the sealing material adheres to the waterproof function of the sealing material. It is essential to use primers to prevent sex inhibition. Since it is considered that the life of buildings such as houses will be further extended, it is expected that the sealing material will be required to have long-term durability of 15 years or more, and further 30 years or more (for example). , See Non-Patent Document 1.).

Japanese Unexamined Patent Publication No. 10-219960

Architectural Sealant-Foundation and Correct Usage-Editorial Board, "Building Sealant-Foundation and Correct Usage-", Japan Sealant Manufacturers Association, 1997, 203-211

The sealant filled in the joint of a wall having a joint structure used for the outer wall of a structure such as a building is exposed not only to rainwater or the like but also to a high temperature environment in summer. It is desirable that the sealing material filled in the joints maintain high elongation characteristics even after such immersion in water or heat exposure. However, in the conventional wall structure including Patent Document 1, it is important from the viewpoint of long-term durability to keep the rate of change of the modulus small after water immersion or heat exposure of the sealant to be filled in the joint portion. It has not been. In addition, when filling the joints with a sealing material, it is essential to apply a primer, and it is difficult to reduce the cause of housing water leakage accidents due to forgetting to apply the primer, uneven coating, and / or coating defects. .. Further, when a ceramic siding material is used, a sealer is generally applied to the siding material including the edge surface for the purpose of surface reinforcement. When a ceramic siding material is used as an outer wall material, usually, after the ceramic siding material is cut and attached to the skeleton at the site, a sealer is applied to the edge which is the cut surface. However, since there is a limit to the adhesive force between the sealer and the siding material, if the modulus of the sealing material is large, peeling or deformation occurs due to an external force such as an earthquake. As a result, peeling of the sealer such as the edge surface may occur in the waterproof structure of the siding material, which may cause water leakage.

Therefore, an object of the present invention is to use a sealing material which has a low rate of change in modulus even after heat exposure, can maintain flexibility, and has a small decrease in elongation at break even after water immersion or heat exposure. The present invention is to provide a wall having a joint structure capable of reducing the occurrence of accidents such as water leakage, a joint construction method, and a one-component room temperature moisture-curable sealant composition.

In order to achieve the above object, the present invention is a wall having a joint structure of a structure, which is arranged at a position adjacent to each other with a gap between the first adherend and the first adherend. A wall having a joint structure is provided which includes a second adherend to be formed and a one-component room temperature moisture-curable sealant which is filled in the gap and has a low rate of change in modulus.

In the wall having the joint structure, the first adherend and the second adherend may be siding materials.

Further, in the wall having the joint structure, it is preferable that the first adherend and the second adherend are ceramic siding materials.

Further, in the wall having the above joint structure, the one-component room temperature moisture-curable sealant is the maximum after immersion in water in the tensile adhesiveness test result tested in accordance with the JTC S-0001 ceramic siding sealant JTC standard. The elongation rate under load is 150% or more, the rate of change of the elongation rate at maximum load after immersion in water is 75% or more, and the modulus at 50% elongation after heating is less than 0.4 N / mm ² . The rate of change of the modulus at 50% elongation after heating is 200% or less, the elongation rate at maximum load after heating is 150% or more, and the rate of change of elongation at maximum load after heating is 75%. The above is preferable.

Further, in the wall having the above-mentioned joint structure, the one-component room temperature moisture-curable sealant is (A) a crosslinkable silicon group-containing organic polymer having a number average molecular weight of 15,000 or more, and (B) two in the molecule. It is preferably obtained by curing a one-component room temperature moisture-curable sealant composition containing the above-mentioned compound having an epoxy group and (C) a ketimine compound having no crosslinkable silicon group.

Further, it is preferable that the one-component room temperature moisture-curable sealant composition further contains (D) a monofunctional epoxy compound in the wall having the joint structure.

Further, in order to achieve the above object, the present invention relates to a second adherend which is arranged at a position adjacent to each other with a gap between the first adherend and the first adherend. A joint construction method including a backup material loading step of loading a backup material in the gap between the joints and a filling step of filling the gap on the backup material with a one-component room temperature moisture-curable sealant composition having a low rate of change in modulus. Provided.

Further, in the above joint construction method, the one-component room temperature moisture-curable sealant obtained by curing the one-component room temperature moisture-curable sealant composition conforms to the JTC S-0001 ceramic siding sealant JTC standard. In the test results of the tensile adhesiveness test, the elongation rate at the maximum load after immersion in water was 150% or more, the change rate of the elongation rate at the maximum load after immersion in water was 75% or more, and 50 after heating. % Elongation modulus is less than 0.4 N / mm ² , the rate of change of 50% elongate modulus after heating is 200% or less, the elongation rate at maximum load after heating is 150% or more, and heating. It is preferable that the rate of change of the elongation rate at the time of the subsequent maximum load is 75% or more.

Further, in order to achieve the above object, the present invention relates to a second adherend which is arranged at a position adjacent to each other with a gap between the first adherend and the first adherend. A one-component room temperature moisture-curable sealant composition filled in the gap between the two, (A) a crosslinkable silicon group-containing organic polymer having a number average molecular weight of 15,000 or more, and (B) two in the molecule. The cured product of the one-component room temperature moisture-curable sealant composition containing the above compound having an epoxy group and the (C) ketimine compound conforms to the JTC S-0001 ceramic siding sealant JTC standard. Provided is a one-component room temperature moisture-curable sealant composition having an initial 50% tensile modulus of less than 0.4 N / mm ² in the test results of tensile adhesion test.

Further, in the above-mentioned one-component room temperature moisture-curable sealant composition, the cured product of the one-component room temperature moisture-curable sealant composition is heat-exposed to be tested in accordance with the JTC S-0001 ceramic siding sealant JTC standard. The 50% tensile modulus after the accelerated test is preferably less than 0.4 N / mm ² .

Further, it is preferable that the monofunctional epoxy compound (D) is further contained in the one-component room temperature moisture-curable sealant composition.

Further, in the above-mentioned one-component room temperature moisture-curable sealant composition, it is preferable that the (C) ketimine compound is synthesized by using a monoamine.

According to the wall having a joint structure, the joint construction method, and the one-component room temperature moisture-curable sealant composition according to the present invention, the rate of change of the modulus is low even after heat exposure, the flexibility can be maintained, and water can be maintained. A wall having a joint structure that can reduce the occurrence of accidents such as water leakage, a joint construction method, and a one-component room temperature moisture curing type sealing material that is constructed using a sealing material that does not decrease in elongation at break even after immersion or heat exposure. The composition can be provided.

It is sectional drawing of the wall which has the joint structure which concerns on this embodiment.

[Outline of wall with joint structure]
The wall having a joint structure according to the present embodiment is a wall having a joint structure of a structure including a building such as a house, and is a wall having a plurality of adherends. A predetermined gap is provided between a plurality of adherends, and the gap is filled with a one-component room temperature moisture-curable sealant having a low rate of change in modulus, so that the gap is immersed in water or exposed to heat. However, a wall with a joint structure that can achieve long-term durability of several decades or more is constructed, in which the modulus does not increase, the flexibility is maintained, and the decrease in elongation at break is small.

[Details of walls with joint structure]
FIG. 1 shows an example of an outline of a conceptual cross section of a wall having a joint structure according to the present embodiment.

The wall 1 having the joint structure according to the present embodiment is a second adherend arranged at a position adjacent to each other with a gap between the first adherend 10 and the first adherend 10. It includes a body 12 and a one-component room temperature moisture-curable sealing material (hereinafter, may be referred to as “sealing material 20” or simply “sealing material”) that is filled in the gap and has a low rate of change in modulus. The one-component room temperature moisture-curable sealant is formed by curing a one-component room temperature moisture-curable sealant composition (hereinafter, may be simply referred to as "sealing material composition").

Further, the wall 1 having a joint structure may be provided with a primer layer 30 between the first adherend 10 and the sealing material 20 and between the second adherend and the sealing material 20. However, in the present embodiment, the primer layer 30 may not be used because the sealing material 20 has excellent adhesiveness to the first adherend 10 and the second adherend 12. Further, in the wall 1 having a joint structure, a backup material 40 may be provided between the structure (not shown) and the sealing material 20.

(1st adherend 10 and 2nd adherend 12)
Specifically, the first adherend 10 and the second adherend 12 are ceramic-based, metal-based, wood-based, and / or resin-based siding materials. In the present embodiment, the first adherend 10 and the second adherend 12 preferably use a ceramic siding material whose main raw material is cement, which has excellent fire resistance and can be mass-produced.

(Seal material 20)
The sealing material 20 according to the present embodiment is a one-component room temperature humidity curing type sealing material. As a one-component room temperature humidity curing type sealing material, "NPO corporation housing exterior technical center standard JTC S-0001 ceramic siding sealing material JTC standard 2004 (September 1, 2004)" (hereinafter, "siding sealing" In the tensile adhesiveness test results tested in accordance with the material standard), a sealing material having an initial 50% tensile modulus of less than 0.4 N / mm ² is used. Further, the one-component room temperature moisture-curable sealant is preferably a sealant having a 50% tensile modulus of less than 0.4 N / mm ² after the heat exposure promotion test.

More specifically, as a one-component room temperature moisture-curable sealant, the elongation rate at the maximum load after immersion in water is 150% or more in the tensile adhesiveness test result tested in accordance with the siding sealant standard. , The rate of change in elongation at maximum load after immersion in water is 75% or more, the modulus at 50% elongation after heating is less than 0.4 N / mm ² , and the change in modulus at 50% elongation after heating. It is preferable to use a sealing material having a rate of 200% or less, an elongation rate at the maximum load after heating of 150% or more, and a change rate of the elongation rate at the maximum load after heating of 75% or more.

The rate of change of the elongation rate at the maximum load after immersion in water is 100 times the value of the "elongation rate at the maximum load after immersion in water" divided by the value of the "elongation rate at the initial maximum load". The rate of change of the 50% elongation modulus after heating is obtained by dividing the value of "50% elongation modulus after heating" by the value of "initial 50% elongation modulus" and multiplying by 100. can get. The rate of change of the elongation rate at the maximum load after heating is multiplied by 100 by dividing the value of the "elongation rate at the maximum load after heating" by the value of the "elongation rate at the initial maximum load". can get. Here, the "initial stage" refers to a time when a one-component room temperature moisture-curable sealant composition is prepared and the prepared composition is cured.

For example, the one-component room temperature moisture-curable sealant composition includes (A) a crosslinkable silicon group-containing organic polymer having a number average molecular weight of 15,000 or more, and (B) two or more epoxy groups in the molecule. A sealant composition containing the compound having the compound and the ketimine compound having no crosslinkable silicon group is used. The one-component room temperature moisture-curable sealant composition may further contain (D) a monofunctional epoxy compound. In the one-component room temperature moisture curing type sealing material, the crosslinkable silicon group is crosslinked at room temperature due to the humidity in the air and is cured. Therefore, the one-component room temperature moisture-curable sealant is usually filled in a container that can block the ingress of moisture so that the performance can be maintained until the user uses it (for example, for one year). Since the one-component moisture-curable sealant composition according to the present embodiment can contain a ketimine compound, in this case, even the one-component type exhibits excellent storage stability.

(Component A: Crosslinkable silicon group-containing organic polymer)
(A) The crosslinkable silicon group of the crosslinkable silicon group-containing organic polymer has a hydroxyl group or a hydrolyzable group bonded to a silicon atom and can be crosslinked by forming a siloxane bond. As the crosslinkable silicon group, for example, the group represented by the general formula (1) is suitable.

In formula (1), R ¹ represents an organic group. R ¹ is preferably a hydrocarbon group having 1 to 20 carbon atoms. Of these, R ¹ is particularly preferably a methyl group. R ¹ may have a substituent. When two or more R ^1s are present, the plurality of R ^1s may be the same or different. X represents a hydroxyl group or a hydrolyzable group, and when two or more Xs are present, a plurality of Xs may be the same or different. a is any integer of 0, 1, 2 or 3. In order to obtain a sealing material composition having a sufficient curing rate in consideration of curability, a is preferably 2 or more, and more preferably 3 in the formula (1). In order to obtain a sealing material composition having sufficient flexibility, a is preferably 2.

Hydrolyzable groups and hydroxyl groups can be bonded to one silicon atom in the range of 1 to 3. When two or more hydrolyzable groups or hydroxyl groups are bonded to the crosslinkable silicon group, they may be the same or different.

The hydrolyzable group represented by X is not particularly limited. For example, an alkoxy group, an acyloxy group, a ketoximate group, an aminooxy group, an alkenyloxy group and the like can be mentioned. Among these, an alkoxy group is preferable from the viewpoint of mild hydrolyzability and easy handling. Among the alkoxy groups, the group having a small number of carbon atoms has a higher reactivity, and the reactivity decreases as the number of carbon atoms increases in the order of methoxy group> ethoxy group> propoxy group. Although it can be selected according to the purpose and application, a methoxy group or an ethoxy group is usually used.

Examples of the crosslinkable silicon group include a trialkoxysilyl group such as a trimethoxysilyl group and a triethoxysilyl group, a dialkoxysilyl group such as −Si (OR) ₃ , a methyldimethoxysilyl group and a methyldiethoxysilyl group, and − Examples thereof include SiR ¹ (OR) ₂ . Here, R is an alkyl group such as a methyl group or an ethyl group. Further, the crosslinkable silicon group may be used alone or in combination of two or more. The crosslinkable silicon group may be bonded to either the main chain or the side chain. From the viewpoint of excellent cured physical properties such as tensile properties of the cured product of the sealant composition, it is preferable that the crosslinkable silicon group is present at the end of the molecular chain. In the organic polymer of the component (A), the number of crosslinkable silicon groups is preferably 1.0 or more and 5 or less on average in one molecule of the organic polymer, and 1.1 to 1 to 3 are preferably present. More preferred.

Specific examples of the main chain skeleton of the crosslinkable silicon group-containing organic polymer include polyoxyalkylene-based polymers such as polyoxypropylene, polyoxytetramethylene, and polyoxyethylene-polyoxypropylene copolymers. Hydrocarbon-based polymers such as ethylene-propylene-based copolymers, polyisobutylene, polyisoprene, polybutadiene, hydrogenated polyolefin-based polymers obtained by hydrogenating these polyolefin-based polymers; 2 bases such as adipic acid Polyester-based polymer obtained by condensation of acid and glycol or ring-open polymerization of lactones; (meth) acrylic acid ester obtained by radical polymerization of monomers such as ethyl (meth) acrylate and butyl (meth) acrylate. System polymer; Vinyl polymer obtained by radical polymerization of (meth) acrylic acid ester-based monomer, vinyl acetate, acrylonitrile, styrene and other monomers; Graft weight obtained by polymerizing vinyl monomer in organic polymer Combined; polysulfide-based polymer; polyamide-based polymer; polycarbonate-based polymer; diallyl phthalate-based polymer and the like can be mentioned. These skeletons may be contained alone in the (A) crosslinkable silicon group-containing organic polymer, or two or more types may be contained in blocks or randomly.

Further, saturated hydrocarbon-based polymers such as polyisobutylene, hydrogenated polyisoprene, and hydrogenated polybutadiene, polyoxyalkylene-based polymers, and (meth) acrylic acid ester-based polymers can be obtained because the glass transition temperature is relatively low. The cured product is preferable because it has excellent cold resistance. Further, the polyoxyalkylene polymer and the (meth) acrylic acid ester polymer are particularly preferable because they have high moisture permeability and are excellent in deep curability when made into a one-component composition.

Among these, an oxyalkylene polymer, a (meth) acrylic acid ester polymer, or a mixture thereof is preferable from the viewpoint of having a large elongation property and a small tensile modulus (tensile stress) required for a sealing material. In particular, as the tensile modulus of the cured product of the sealant composition, the initial 50% tensile modulus at a test temperature of 23 ° C. measured in accordance with the siding sealant standard is less than 0.4 N / mm ^2. preferable. The 50% tensile modulus specified in the JASS8 waterproofing work (Architectural Institute of Japan) is also preferably a low value. Further, since the sealing material, particularly the sealing material used for construction, is exposed outdoors for a long period of time, it is preferable that the tensile modulus is maintained even after exposure under adverse conditions. For example, it is preferable that the tensile modulus after the heat exposure promotion test does not exceed 0.4 N / mm ² .

The polyoxyalkylene polymer is essentially a polymer having a repeating unit represented by the general formula (2).
-R ^2- O -... (2)
In the general formula (2), R ² is a linear or branched alkylene group having 1 to 14 carbon atoms, preferably a linear or branched alkylene group having 1 to 14 carbon atoms, and has 2 to 4 carbon atoms. The linear or branched alkylene group of is more preferable.

As a specific example of the repeating unit represented by the general formula (2),
_{-CH 2 O -, - CH 2} CH 2 O -, - CH 2 CH (CH 3) O -, - CH 2 CH (C 2 H 5) O -, - CH 2 C (CH 3) 2 O-, -CH ₂ CH ₂ CH ₂ CH ₂ O- and the like can be mentioned. The main chain skeleton of the polyoxyalkylene polymer may consist of only one type of repeating unit or may consist of two or more types of repeating units. In particular, a main chain skeleton composed of a polymer containing oxypropylene as a main component is preferable.

The molecular weight of the oxyalkylene polymer having a crosslinkable silicon group is preferably high because it reduces the tensile modulus, which is the initial tensile property of the cured product, and increases the elongation at break. In the present embodiment, the lower limit of the number average molecular weight of the oxyalkylene polymer is preferably 15,000, more preferably 18,000 or more, and even more preferably 20,000 or more. As the molecular weight increases, the viscosity of the polymer increases and the viscosity of the sealant composition also increases. Therefore, a polymer containing a polymer having a number average molecular weight of 20,000 or more is also preferable. The upper limit of the number average molecular weight is 50,000, more preferably 40,000. The number average molecular weight according to this embodiment is a polystyrene-equivalent molecular weight obtained by gel permeation chromatography. If the number average molecular weight is less than 15,000, the tensile modulus and elongation at break may not be sufficient, and if it exceeds 50,000, the viscosity of the composition may increase and workability may decrease.

An oxyalkylene polymer having a crosslinkable silicon group and having a number average molecular weight of 15,000 or more (hereinafter, may be referred to as a component (A1)) and another organic polymer having a crosslinkable silicon group (hereinafter, (hereinafter,). When A2) component is used, the component (A1) is preferably 30% by mass or more, more preferably 35% by mass or more, based on the total amount of the (A1) component and the (A2) component. It is preferable, and 40% by mass or more is particularly preferable.

When the content of crosslinkable silicon groups in the oxyalkylene polymer is appropriately reduced, the crosslink density in the cured product is reduced, so that the cured product becomes more flexible at the initial stage, the modulus characteristics are reduced, and the elongation at break is reduced. Becomes larger. In the oxyalkylene polymer, the number of crosslinkable silicon groups is preferably 1.2 or more and 2.8 or less, and 1.3 or more and 2.6 or less, on average in one molecule of the polymer. Is more preferable, and it is further preferable that 1.4 or more and 2.4 or less are present. If the number of crosslinkable silicon groups contained in the molecule is less than one, the curability becomes insufficient, and if it is too large, the network structure becomes too dense and good mechanical properties are not exhibited. In the case of a bifunctional polymer having a linear main chain skeleton, the average number of crosslinkable silicon groups in the polymer is 1.2 or more and less than 1.9 in one molecule of the polymer. It is more preferable that the number is 1.25 or more and 1.8 or less, and more preferably 1.3 or more and less than 1.7. Further, in particular, in the case of producing a so-called non-plastic compound sealing material composition which does not contain a low molecular weight plasticizer having a molecular weight of 800 or less, such as a phthalate ester plasticizer, and further having a molecular weight of 1000 or less, crosslinkability is obtained. It is preferable that the number of silicon groups is 1.2 or more and 1.8 or less, more preferably 1.3 or more and 1.7 or less, on average in one molecule of the polymer.

The oxyalkylene polymer having a crosslinkable silicon group may be linear or branched. From the viewpoint of reducing the tensile modulus, the oxyalkylene polymer having a crosslinkable silicon group is preferably a linear polymer. In particular, when producing a non-plasticized sealing material composition, it is preferably linear. The molecular weight distribution (Mw / Mn) of the oxyalkylene polymer having a crosslinkable silicon group is preferably 2 or less, particularly preferably 1.6 or less.

Examples of the method for synthesizing the polyoxyalkylene polymer include, for example, a polymerization method using an alkali catalyst such as KOH, for example, a polymerization method using a compound metal cyanide complex catalyst, and the like, but the method is not particularly limited. According to the polymerization method using a compound metal cyanide complex catalyst, a polyoxyalkylene polymer having a number average molecular weight of 6,000 or more and a high molecular weight of Mw / Mn of 1.6 or less and a narrow molecular weight distribution can be obtained.

The main chain skeleton of the polyoxyalkylene polymer may contain other components such as a urethane bond component. As the urethane bond component, for example, it is obtained from a reaction between an aromatic polyisocyanate such as toluene (toluene) diisocyanate and diphenylmethane diisocyanate; an aliphatic polyisocyanate such as isophorone diisocyanate and a polyoxyalkylene polymer having a hydroxyl group. Ingredients can be mentioned.

A polyoxyalkylene polymer having a functional group such as an unsaturated group, a hydroxyl group, an epoxy group, or an isocyanate group in the molecule is reacted with a functional group having a reactivity with this functional group and a crosslinkable silicon group. As a result, a crosslinkable silicon group can be introduced into the polyoxyalkylene polymer (hereinafter referred to as a polymer reaction method).

As an example of the polymer reaction method, a hydrosilane having a crosslinkable silicon group or a mercapto compound having a crosslinkable silicon group is allowed to act on an unsaturated group-containing polyoxyalkylene polymer to form hydrosilylation or mercapto, and the crosslinkable silicon group is formed. A method for obtaining a polyoxyalkylene polymer having the above can be mentioned. The unsaturated group-containing polyoxyalkylene polymer is an unsaturated group obtained by reacting an organic polymer having a functional group such as a hydroxyl group with an organic compound having an active group and an unsaturated group that are reactive with this functional group. A polyoxyalkylene polymer containing the above can be obtained.

Further, as another example of the polymer reaction method, a method of reacting a polyoxyalkylene polymer having a hydroxyl group at the terminal with an isocyanate group and a crosslinkable silicon group, or a polyoxyalkylene-based weight having an isocyanate group at the terminal. Examples thereof include a method of reacting the coalescence with an active hydrogen group such as a hydroxyl group or an amino group, and a crosslinkable silicon group. When an isocyanate compound is used, a polyoxyalkylene polymer having a crosslinkable silicon group can be easily obtained.

The crosslinkable silicon group may be used alone or in combination of two or more.

As the (meth) acrylic acid ester-based monomer constituting the main chain of the (meth) acrylic acid ester-based polymer, various monomers can be used. For example, (meth) acrylic acid-based monomers such as acrylic acid; methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-butyl (meth) acrylic acid, 2-ethylhexyl (meth) acrylic acid, (meth) acrylic. (Meta) acrylic acid alkyl ester-based monomers such as stearyl acid; alicyclic (meth) acrylic acid ester-based monomers; aromatic (meth) acrylic acid ester-based monomers; (meth) acrylic acid 2-methoxyethyl and the like (meth) ) Acrylic acid ester-based monomer; silyl group-containing (meth) acrylic acid ester-based monomer such as γ- (methacryloyloxypropyl) trimethoxysilane, γ- (methacryloyloxypropyl) dimethoxymethylsilane; (meth) acrylic acid derivative; Examples thereof include fluorine-containing (meth) acrylic acid ester-based monomers.

In the (meth) acrylic acid ester-based polymer, the following vinyl-based monomers can be copolymerized together with the (meth) acrylic acid ester-based monomer. Examples of vinyl-based monomers include styrene, maleic anhydride, vinyl acetate and the like. In addition, acrylic acid and glycidyl acrylate may be contained as the monomer unit (hereinafter, also referred to as another monomer unit).

These may be used alone or in combination of two or more. From the viewpoint of physical properties of the product, a polymer composed of a (meth) acrylic acid-based monomer is preferable. Further, a (meth) acrylic acid ester-based polymer in which one or more (meth) acrylic acid alkyl ester monomers are used and another (meth) acrylic acid monomer is used in combination as necessary is more preferable. Further, by using a silyl group-containing (meth) acrylic acid ester-based monomer in combination, the number of silicon groups in the (meth) acrylic acid ester-based polymer (A) can be controlled. A methacrylic acid ester-based polymer composed of a methacrylic acid ester monomer is particularly preferable because of its good adhesiveness. Further, in the case of lowering the viscosity, imparting flexibility, and imparting adhesiveness, it is preferable to appropriately use an acrylic acid ester monomer. In this embodiment, the (meth) acrylic acid represents acrylic acid and / or methacrylic acid.

As a method for producing the (meth) acrylic acid ester-based polymer, for example, a radical polymerization method using a radical polymerization reaction can be used. Radical polymerization methods include a radical polymerization method (free radical polymerization method) in which a predetermined monomer unit is copolymerized using a polymerization initiator, and a controlled radical capable of introducing a reactive silyl group at a controlled position such as a terminal. A polymerization method can be mentioned. However, a polymer obtained by a free radical polymerization method using an azo compound, a peroxide or the like as a polymerization initiator generally has a large molecular weight distribution value of 2 or more and a high viscosity. Therefore, when a (meth) acrylic acid ester-based polymer having a narrow molecular weight distribution and a low viscosity and a (meth) acrylic acid ester-based polymer having a crosslinkable functional group at the end of the molecular chain is obtained at a high ratio, , It is preferable to use the controlled radical polymerization method.

Examples of the controlled radical polymerization method include a free radical polymerization method and a living radical polymerization method using a chain transfer agent having a specific functional group. It is preferable to adopt a living radical polymerization method such as a Reversible Addition-Fragmentation chain Transfer (RAFT) polymerization method or a radical polymerization method (Transition-Metal-Mediated LivingRadical Polymerization) using a transition metal complex. Further, a reaction using a thiol compound having a reactive silyl group, a reaction using a thiol compound having a reactive silyl group, and a metallocene compound are also preferable.

These crosslinkable silicon groups may be used alone or in combination of two or more. Specifically, a group consisting of a polyoxyalkylene polymer having a crosslinkable silicon group, a saturated hydrocarbon polymer having a crosslinkable silicon group, and a (meth) acrylic acid ester polymer having a crosslinkable silicon group. An organic polymer obtained by blending two or more kinds selected from the above can also be used. In particular, an organic polymer obtained by blending a polyoxyalkylene polymer having a crosslinkable silicon group and a (meth) acrylic acid ester polymer having a crosslinkable silicon group has excellent properties. When applied to the sealing material composition according to the present embodiment, the elongation rate at the maximum load and the adhesive force can be increased.

Various methods can be mentioned as a method for producing an organic polymer in which a polyoxyalkylene polymer having a crosslinkable silicon group and a (meth) acrylic acid ester polymer having a crosslinkable silicon group are blended. For example, it has a crosslinkable silicon group and the molecular chain is substantially the general formula (3) :.
-CH ₂ -C (R ³ ) (COOR ⁴ ) -... (3)
(In the formula, R ³ represents a hydrogen atom or a methyl group, R ⁴ represents an alkyl group having 1 to 5 carbon atoms), and a (meth) acrylic acid ester monomer unit represented by the general formula (4):
-CH _2- C (R ³ ) (COOR ⁵ ) -... (4)
(In the formula, R ³ is the same as described above, R ⁵ is an alkyl group having 6 or more carbon atoms), and a crosslinkable silicon group is added to the copolymer composed of the (meth) acrylic acid ester monomer unit. Examples thereof include a method of blending and producing a polyoxyalkylene polymer having the above.

The ^{R 4} in general formula (3), for example, a methyl group, an ethyl group, a propyl group, n- butyl group, the carbon number of a t- butyl group and the like 5, preferably carbon atoms 1 to 4, further An alkyl group having 1 to 2 carbon atoms is preferable. The alkyl group of R ⁴ may alone, or may be a mixture of two or more.

The ^{R 5} of the general formula (4), for example, 2-ethylhexyl group, lauryl group, the number of carbon atoms such as stearyl group of 6 or more, usually carbon atoms from 7 to 30, preferably long having 8 to 20 carbon atoms Alkyl groups of chains can be mentioned. The alkyl group of R ⁵ is as in the case of R ^4, may be alone or in admixture.

The molecular chain of the (meth) acrylic acid ester-based copolymer is substantially composed of the monomer units of the formulas (3) and (4). Here, "substantially" means that the total of the monomer units of the formulas (3) and (4) present in the copolymer exceeds 50% by mass. The total of the monomer units of the formula (3) and the formula (4) is preferably 70% by mass or more. The abundance ratio of the monomer unit of the formula (3) to the monomer unit of the formula (4) is preferably 95: 5 to 40:60, more preferably 90: 10 to 60:40 in terms of mass ratio.

It has a crosslinkable silicon group (meth) used in a method for producing an organic polymer obtained by blending a polyoxyalkylene polymer having a crosslinkable silicon group and a (meth) acrylic acid ester polymer having a crosslinkable silicon group. As the acrylic acid ester-based polymer, for example, a (meth) acrylic acid alkyl ester monomer unit having a crosslinkable silicon group and having a substantially (1) alkyl group having 1 to 8 carbon atoms in the molecular chain. , (2) (Meta) acrylic acid ester-based copolymer such as (meth) acrylic acid ester-based copolymer containing a (meth) acrylic acid alkyl ester monomer unit having an alkyl group having 10 or more carbon atoms. Coalescence can also be used.

The number average molecular weight of the (meth) acrylic acid ester-based polymer is such that when the glass transition temperature (Tg) of the (meth) acrylic acid ester-based polymer is less than 0 ° C., the (meth) acrylic acid ester-based polymer is acrylic. When mainly composed of butyl acid monomer units, 20,000 or more is preferable, 30,000 or more is more preferable, 35,000 or more is further preferable, and 40,000 or more is particularly preferable. Further, when the glass transition temperature (Tg) of the (meth) acrylic acid ester-based polymer is 0 ° C. or higher, particularly when the (meth) acrylic acid ester-based polymer is mainly composed of methyl methacrylate monomer units. The number average molecular weight is preferably 600 or more and 10,000 or less, more preferably 600 or more and 5,000 or less, and further preferably 1,000 or more and 4,500 or less. By setting the number average molecular weight in this range, the compatibility with the polyoxyalkylene polymer having a crosslinkable silicon group is improved. The (meth) acrylic acid ester-based polymer may be used alone or in combination of two or more. The blending ratio of the polyoxyalkylene polymer having a crosslinkable silicon group and the (meth) acrylic acid ester polymer having a crosslinkable silicon group is not particularly limited, but of the (meth) acrylic acid ester polymer. When the glass transition temperature (Tg) is less than 0 ° C., especially when the (meth) acrylic acid ester-based polymer is mainly composed of the butyl acrylate-based polymer unit, the (meth) acrylic acid ester-based polymer and polyoxy The amount of the (meth) acrylic acid ester-based polymer is preferably in the range of 30 to 90 parts by mass, and preferably in the range of 40 to 80 parts by mass with respect to 100 parts by mass in total with the alkylene-based polymer. More preferably, it is in the range of 50 to 70 parts by mass. If the amount of the (meth) acrylic acid ester-based polymer is more than 90 parts by mass, the viscosity becomes high and the workability deteriorates, which is not preferable. Further, when the glass transition temperature (Tg) of the (meth) acrylic acid ester-based polymer is 0 ° C. or higher, particularly when the (meth) acrylic acid ester-based polymer is mainly composed of methyl methacrylate monomer units. The amount of the (meth) acrylic acid ester-based polymer is preferably in the range of 10 to 60 parts by mass with respect to a total of 100 parts by mass of the (meth) acrylic acid ester-based polymer and the polyoxyalkylene-based polymer. It is more preferably in the range of 20 to 50 parts by mass, and even more preferably in the range of 25 to 45 parts by mass. If the amount of the (meth) acrylic acid ester-based polymer is more than 60 parts by mass, the viscosity becomes high and the workability deteriorates, which is not preferable.

Further, in the present embodiment, an organic polymer obtained by blending a saturated hydrocarbon-based polymer having a crosslinkable silicon group and a (meth) acrylic acid ester-based copolymer having a crosslinkable silicon group can also be used. Another method for producing an organic polymer obtained by blending a (meth) acrylic acid ester-based copolymer having a crosslinkable silicon group is in the presence of an organic polymer having a crosslinkable silicon group (meth). ) A method of polymerizing an acrylic ester-based monomer can be used.

(B component: polyfunctional epoxy resin)
Various epoxy resins can be used as the compound having two or more epoxy groups in the molecule which is the component (B) according to the present embodiment. Examples of the epoxy resin include epichlorohydrin-bisphenol A type epoxy resin, epichlorohydrin-bisphenol F type epoxy resin, flame retardant epoxy resin such as tetrabromobisphenol A glycidyl ether, novolak type epoxy resin, and hydrogenated bisphenol A type epoxy resin. , Bisphenol A propylene oxide adduct glycidyl ether type epoxy resin, poxybenzoate glycidyl ether ester type epoxy resin, maminophenol type epoxy resin, diaminodiphenylmethane type epoxy resin, urethane modified epoxy resin, various alicyclic epoxy resins, Unsaturated polymers such as glycidyl ethers of polyhydric alcohols such as N, N diglycidyl aniline, N, N diglycidyl-o toluidine, triglycidyl isocyanurate, polyalkylene glycol diglycidyl ether, and glycerin, hydant-in type epoxy resin, and petroleum resin Epoxy products and the like. Among these epoxy resins, a compound containing at least two epoxy groups represented by the following formula (5) in the molecule has high reactivity at the time of curing, and the cured product forms a three-dimensional network. It is preferable from the viewpoint of ease of use.

Further, as the component (B), epoxy resins having an aromatic ring such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AD type epoxy resins, and novolak type epoxy resins are more preferable. Among such epoxy resins having an aromatic ring, from the viewpoint of adhesion to a base material, a compound having an aromatic ring and not having an oxyalkylene chain, which is a segment that imparts flexibility. Is particularly preferable. Further, bisphenol A type epoxy resins are most preferable, and bisphenol A type epoxy resins having no oxyalkylene chain are particularly preferable. A compound having two or more epoxy groups in the molecule has a function of improving the adhesiveness of an organic polymer having a crosslinkable silicon group, particularly an oxyalkylene polymer having a crosslinkable silicon group. The epoxy resin is preferably liquid at room temperature. The molecular weight of the epoxy resin is preferably 500 or less.

The amount of the (B) polyfunctional epoxy resin used is in the range of 1 to 50 parts by mass with respect to 100 parts by mass of the (A) organic polymer having a crosslinkable silicon group. If it is less than 1 part by mass, the adhesiveness of the cured product of the sealing material composition becomes insufficient, and if it exceeds 50 parts by mass, the flexibility of the cured product of the sealing material composition becomes insufficient. The preferred range is 1 to 30 parts by mass, more preferably 1 to 20 parts by mass, and further preferably 1 to 10 parts by mass.

(C component: ketimine compound having no crosslinkable silicon group)
In the sealant composition according to the present embodiment, as the component (C), a compound having a ketimine group in the molecule and not having a crosslinkable silicon group (hereinafter, also referred to as ketimine) is used. By adding the component (C) according to the present embodiment to the sealing material composition, the rate of change in the modulus of the cured product of the sealing material composition can be reduced. That is, by adding the component (C) to the sealing material composition, it is possible to prevent the modulus from exceeding a predetermined value even after the cured product of the sealing material composition is heat-exposed, and maintain the flexibility. At the same time, it is possible to suppress a decrease in elongation at break after immersion in water or heat exposure. Further, by adding the component (C) to the sealing material composition, sufficient adhesiveness to the adherend can be ensured even without a primer.

Ketimine exists stably in the absence of water, is decomposed into primary amines and ketones by water, and the resulting primary amine acts as a silanol condensation catalyst. After that, by reacting with the epoxy resin, the silanol condensation catalytic action expires, and the cured product can be maintained in a low modulus even after heat exposure. Further, when ketimine is used, it does not react with the epoxy resin during storage of the composition, so that it can be made into a one-component composition. Such ketimine can be obtained by a condensation reaction between an amine compound and a carbonyl compound.

Various amine compounds and carbonyl compounds can be used for the synthesis of ketimine. Examples of the amine compound include monoamines such as 2-ethylhexylamine, laurylamine, stearylamine and i-stearylamine; diamines such as ethylenediamine, tetramethylenediamine and hexamethylenediamine; 1,2,3-triaminopropane and tetra. Polyvalent amines such as (aminomethyl) methane; polyalkylene polyamines such as diethylenetriamine and triethylenetriamine; polyoxyalkylene polyamines and the like can be used.

Examples of the carbonyl compound include aldehydes such as acetaldehyde and benzaldehyde; cyclic ketones such as cyclohexanone; aliphatic ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; β-dicarbonyl such as acetylacetone, ethyl acetoacetate and diethyl malonate. Compounds and the like can be used. When an imino group is present in ketimine, the imino group may be reacted with a styrene oxide; a glycidyl ether such as butyl glycidyl ether or allyl glycidyl ether; a glycidyl ester or the like.

For the purpose of keeping the cured product of the sealant composition flexible, it is possible to use a ketiminated monoamine obtained by a condensation reaction of a monoamine and a carbonyl compound, or a ketiminated diamine obtained by a condensation reaction of a diamine and a carbonyl compound. It is preferable to use a ketiminated monoamine, more preferably. These ketimins may be used alone or in combination of two or more. The amount of the component (C) used can be in the range of 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymer of the component (A), and can be used in the range of 1 to 10 parts by mass. preferable.

(D component: monofunctional epoxy compound)
Examples of the compound having one epoxy group in the molecule (D) according to the present embodiment and not having a crosslinkable silicon group (hereinafter, also referred to as a monofunctional epoxy compound) include alkyl monoglycidyl ether and phenyl glycidyl. Ethers, linear alcohol monoglycidyl ethers, polyglycol glycidyl ethers, glycidyl esters such as glycidyl methacrylate, glycidyl esters or mixtures thereof, 1, epoxy dodecane, epoxy hydrocarbons such as styrene oxide or mixtures thereof, cyclohexane oxide, 4 -Vinyl epoxycyclohexane, 3,4-epoxycyclohexylmethanol, 3,4-epoxycyclohexylmethylmethacrylate, di2-ethylhexyl epoxyhexahydrophthalate, di2-ethylhexyl epoxyhexahydrophthalate, formulas (a)-( Examples thereof include an alicyclic epoxy compound represented by g) and the like. Of these, alicyclic epoxy compounds are preferred.

The amount of the monofunctional epoxy compound (D) used is in the range of 1 to 100 parts by mass with respect to 100 parts by mass of the organic polymer having a crosslinkable silicon group of the component (A). It is preferably in the range of 10 to 500 parts by mass and preferably in the range of 50 to 200 parts by mass with respect to 100 parts by mass of the epoxy resin.

Here, by adding a compound having one epoxy group in the molecule of the component (D) and no crosslinkable silicon group together with the component (B), the flexibility of the cured product can be improved and the product is immersed in water. It is possible to prevent deterioration of elongation characteristics after or after heat exposure. The sealant composition according to this embodiment can have an initial 50% tensile modulus of less than 0.4 N / mm ² at a test temperature of 23 ° C. measured in accordance with the siding sealant standard. The component (D) is required to have no crosslinkable silicon group. When it has a crosslinkable silicon group, it may be difficult to improve the flexibility because the crosslinkable silicon group causes a crosslink reaction with the polymer of the component (A).

(Ketiminated aminosilane compound)
The sealant composition according to the present embodiment may contain an alkoxysilane compound that reacts with water to produce an amine compound having at least one alkoxysilyl group in one molecule. The alkoxysilyl group is a silicon atom-containing group in which an alkoxy group is bonded to a silicon atom. Examples of such a compound include a compound in which the amino group of an amine compound having an alkoxysilyl group (hereinafter, also referred to as an aminosilane compound) is ketiminated with a carbonyl compound. Examples of the aminosilane compound to be ketiminated include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ- (2aminoethyl) aminopropyltrimethoxysilane, and γ- (2aminoethyl) aminopropyltriethoxysilane. Examples thereof include silane and γ- (2-aminoethyl) aminopropylmethyldimethoxysilane.

Further, as the carbonyl compound, the carbonyl compound described in the description of the component (C) can be used. When an imino group is present in ketimine, the imino group may be reacted with a styrene oxide; a glycidyl ether such as butyl glycidyl ether or allyl glycidyl ether; a glycidyl ester or the like.

When a compound in which an amino group is ketiminated or the like is used, it does not react with the epoxy resin during storage of the composition, so that a one-component composition can be obtained. The ketiminated aminosilane compound acts as an adhesive-imparting agent, and also acts as a curing agent and a curing catalyst for epoxy resins. Two or more kinds of ketiminated aminosilane compounds can be used in combination.

The amount of the ketiminated aminosilane compound used can be in the range of 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymer of the component (A), and is preferably added in the range of 1 to 10 parts by mass.

(Other compounding substances)
The sealant composition according to the present embodiment contains an epoxy resin curing agent, a plasticizer, a filler, a silane coupling agent, a silanol condensation catalyst, a diluent, a dehydrating agent, an antiaging agent, and an ultraviolet absorber other than the component (C). , Lubricants, pigments, foaming agents and the like may be further added.

As the epoxy resin curing agent other than the component (C), one or a plurality of various epoxy resin curing agents can be selected and used. Examples of such an epoxy resin curing agent include amines, acid anhydrides, imidazoles and other curing agents. However, since it may be difficult to cure the epoxy resin at room temperature to obtain a one-component composition with a curing agent having strong activity, it should be used within a range in which the purpose of the sealing material according to the present embodiment is achieved. preferable.

Examples of the plasticizer include phthalates such as dioctylphthalate; aliphatic dibasic acid esters such as dioctyl adipate; glycol esters; aliphatic esters; phosphoric acid esters; polyester plasticizers; polypropylene glycol and Examples thereof include polyethers such as derivatives; hydrocarbon plasticizers; chlorinated paraffins; low molecular weight acrylate esters and the like. These plasticizers may be used alone or in combination of two or more. In particular, when an acrylic acid ester polymer is used, the weather resistance of the cured product can be improved.

When a plasticizer is used, 10 to 300 parts by mass can be used with respect to 100 parts by mass of the component (A), and it is preferable to use it in the range of 20 to 250 parts by mass. If the amount of the plasticizer used is less than 10 parts by mass, the viscosity of the composition may become too high, and if the amount used exceeds 300 parts by mass, the plasticizer may seep out from the cured product. It is not preferable because it may occur. The sealant composition according to the present embodiment produces a non-plasticized sealant composition that does not contain a low molecular weight plasticizer having a molecular weight of 800 or less, such as a phthalate ester plasticizer, and further having a molecular weight of 1000 or less. Especially useful in some cases.

Fillers include reinforcing fillers such as fumed silica, sedimentary silica, silicic anhydride, and carbon black; calcium carbonate, magnesium carbonate, silica soil, calcined clay, clay, talc, hardened titanium, bentonite, organic bentonite. , Fillers such as ferric oxide, zinc oxide, active zinc flower, silas balloon, etc .; Fibrous fillers such as asbestos, glass fiber, and filaments can be used.

When a cured product having high strength is produced by adding these fillers, it is preferable to use a filler mainly selected from fumed silica, carbon black, surface-treated fine calcium carbonate and the like. Further, in the case of producing a cured product having low strength and high elongation, it is preferable to use a filler mainly selected from titanium oxide, calcium carbonate, magnesium carbonate, shirasu balloon and the like. These fillers may be used alone or in combination of two or more.

When a filler is used, it can be used in the range of 1 to 300 parts by mass, preferably in the range of 5 to 300 parts by mass, and in the range of 5 to 250 parts by mass with respect to 100 parts by mass of the component (A). It is more preferable to use it.

The sealant composition according to the present embodiment may further contain a silane coupling agent. The sealant composition according to the present embodiment can improve the adhesiveness to a general adherend such as metal, plastic, and glass by blending a silane coupling agent.

Examples of the silane coupling agent include amino group-containing silanes; epoxy group-containing silanes; mercapto group-containing silanes; vinyl-type unsaturated group-containing silanes; chlorine atom-containing silanes; isocyanate-containing silanes; alkyl silanes. ; Phenyl group-containing silanes; Isocyanurate group-containing silanes and the like, but are not limited thereto. Further, modified amino group-containing silanes in which the amino group is modified by reacting the amino group-containing silanes with the epoxy group-containing compound containing the above silanes, the isocyanate group-containing compound, and the (meth) acryloyl group-containing compound are used. You may.

The blending ratio of the silane coupling agent is not particularly limited, but is preferably 0.2 to 20 parts by mass, more preferably 0.3 to 15 parts by mass, based on 100 parts by mass of the (B) crosslinkable silicon group-containing polymer. It is preferable, and 0.5 to 10 parts by mass is more preferable. These silane coupling agents may be used alone or in combination of two or more.

Examples of the silanol condensation catalyst include organic tin compounds such as dibutyltin dilaurate, dibutyltin diacetate, a reaction product of dioctyl tin oxide and a silicate compound, and a reaction product of dibutyl tin oxide and a phthalate ester: tin carboxylate, carboxylic acid. Carboxylic acid metal salts such as bismuth acid and iron carboxylate: aliphatic amines, aromatic amines, amidines such as DBU, guanidines such as diphenylguanidine, amine compounds such as biguanide: carboxylic acids such as versatic acid: Titanium compounds such as diisopropoxytitanium bis (ethylacetate), alkoxy metals such as aluminum compounds: Inorganic acid: Boron trifluoride Borone trifluoride complex such as ethylamine complex: Aluminum monoacetylacetonate bis (ethylacetoacetate) ) And the like, and examples thereof. Of these, organotin compounds are preferred. The silanol condensation catalyst acts as a curing catalyst for the polymer having a crosslinkable silicon group of the component (A). When a silanol condensation catalyst is used, it can be used in the range of 0.1 to 20 parts by mass with respect to 100 parts by mass of the component (A), and is preferably used in the range of 0.2 to 10 parts by mass.

The sealant composition according to this embodiment preferably further contains a diluent. By containing a diluent, physical properties such as viscosity can be adjusted. As the diluent, various diluents can be used. Examples of the diluent include saturated hydrocarbon solvents such as normal paraffin and isoparaffin, α-olefin derivatives such as linearene dimer (trade name of Idemitsu Kosan Co., Ltd.), aromatic hydrocarbon solvents, alcohol solvents, and ester solvents. Examples thereof include a solvent, a citrate ester solvent such as acetyltriethyl citrate, and various solvents such as a ketone solvent.

When considering the safety of the obtained sealing material composition, it is desirable that the sealing material composition has a high flash point, and it is preferable that the amount of volatile substances from the sealing material composition is small. Therefore, the flash point of the diluent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher. When two or more kinds of diluents are mixed, it is preferable that the flash point of the mixed diluents is 70 ° C. or higher. However, in general, a diluent having a high flash point tends to have a low diluting effect on the sealing material composition, so it is preferable to use a diluent having a flash point of 250 ° C. or lower.

When both the safety and the dilution effect of the sealant composition according to the present embodiment are considered, the diluent is preferably a saturated hydrocarbon solvent, and more preferably normal paraffin and isoparaffin. The carbon number of normal paraffin and isoparaffin is preferably 10 to 16.

The mixing ratio of the diluent is preferably in the range of 0 to 50 parts by mass, and more preferably in the range of 0.1 to 30 parts by mass with respect to 100 parts by mass of the (A) organic polymer. , 0.1 to 15 parts by mass is more preferable. The diluent may be used alone or in combination of two or more.

Examples of the dehydrating agent include silane compounds such as vinyltrimethoxysilane, tetraethoxysilane and tetramethoxysilane; and ester compounds such as methyl orthoformate and ethyl orthoformate. These dehydrating agents may be used alone or in combination of two or more. As the dehydrating agent, vinyl trimethoxysilane is particularly preferable.

The content of the dehydrating agent is preferably in the range of 0.5 to 20 parts by weight, and more preferably in the range of 1 to 15 parts by weight with respect to 100 parts by mass of the component (A). If the content of the dehydrating agent in the sealant composition is too low, the effect obtained by the dehydrating agent may not be sufficient. Further, if the content of the dehydrating agent in the sealing material composition is too high, the curability of the sealing material composition may decrease.

(Primer layer 30)
The primer layer 30 can be provided on the side surface of the first adherend 10 and the side surface of the second adherend 20. Specifically, the primer layer 30 includes at least one reactive resin selected from the group consisting of synthetic rubber-based resins, acrylic-based resins, urethane-based resins, epoxy-based resins, silicone-based resins, and silane-based resins, and silane. It is formed by applying a primer containing a coupling agent and an organic solvent to the side surface of the first adherend 10 and the side surface of the second adherend 20.

(Backup material 40)
The backup material 40 is formed of an elastic material, and can be formed by using a natural rubber, a synthetic resin such as a styrene-butadiene-styrene block copolymer (SBS), and / or a foam thereof. The backup material 40 has an adhesive layer or an adhesive layer that can be attached to the bottom of the gap along the gap between the first adherend 10 and the second adherend 12. It is composed of.

The cured product of the sealing material composition according to the present embodiment has excellent flexibility (low modulus), and the cured product has water resistance and heat resistance. Therefore, the sealing material, particularly the sealing material for siding boards of buildings and the like. Can be used as. Further, the cured product of the sealing material composition according to the present embodiment can also be used for frame members such as window frames and door frames, and for sealing the boundary between the eaves and the wall material.

[About joint construction method]
The wall having the joint structure according to the present embodiment is produced according to the following steps. First, the gap between the first adherend 10 and the second adherend 12 arranged adjacent to each other with a gap between the first adherend 10 and each adherence. Clean the area of contact with the body sealant (cleaning process). Next, the backup material 40 is placed in the gap between the first adherend 10 and the second adherend 12 arranged adjacent to each other with a gap between the first adherend 10 and the first adherend 10. (Back-up material loading process). Then, a masking tape is attached to the edge of the joint, that is, the edge on the gap side of the first adherend 10 and the edge on the gap side of the second adherend 12 (masking step).

Subsequently, if necessary, a primer is applied to the surface facing the gap of the first adherend 10 and the surface facing the gap of the second adherend 12 (primer coating step). However, since it is not essential to use a primer in this embodiment, the primer application step may be omitted. Then, the gap on the backup material 40 is filled with a one-component room temperature moisture-curable sealant composition having a low rate of change in modulus (filling step). Next, the surface of the one-component room temperature moisture-curable sealant composition is smoothed (spatula finishing step). After the spatula finishing process, remove the masking tape (mask removal process). Then, it is cured for a predetermined time (curing process). As a result, a wall having a joint structure according to the present embodiment is produced.

(Effect of embodiment)
The wall having the joint structure according to the present embodiment has an elongation rate at the maximum load after water immersion and a maximum load after water immersion in the gap between the first adherend 10 and the second adherend 12. Rate of change in elongation rate, modulus at 50% elongation after heating, modulus change rate at 50% elongation after heating, elongation rate at maximum load after heating, and elongation rate at maximum load after heating Since the sealant 20 is filled with a sealant 20 having a rate of change in a predetermined range, the life of a building such as a house can be extended even if it is immersed in water or exposed to heat.

Further, the sealing material 20 according to the present embodiment is formed from a one-component room temperature humidity curing type sealing material composition, and the one-component room temperature moisture curing type sealing material which is a cured product of the one-component room temperature moisture curing type sealing material composition is , The decrease in elongation characteristics due to water immersion and heat exposure is small. Further, in the conventional sealing material, when the porous adherend is used without applying a primer, the adhesiveness to the adherend is significantly reduced in the presence of moisture (particularly, the modulus at 50% elongation). However, even when it is practically sufficiently low, the elongation rate at the maximum load is greatly reduced.) The one-component room temperature moisture-curable sealant composition according to the present embodiment has adhesiveness to an adherend. It is excellent in terms of performance, and sufficient performance (that is, sufficient adhesive performance, sufficiently low modulus, sufficiently large elongation rate at maximum load, etc.) can be achieved without using a primer. Therefore, since the one-component room temperature moisture-curable sealant according to the present embodiment can fill the joints without using a primer, a housing water leakage accident due to forgetting to apply the primer, uneven coating, and / or coating defect at the time of joint construction. The cause of the occurrence can be reduced.

Further, the sealing material according to the present embodiment has low modulus, large elongation, and excellent water resistance and heat resistance. Therefore, the sealing material according to the present embodiment can be used for long-term exposure to the outdoors, or can be used indoors around water such as a bathroom or kitchen. In particular, it can be suitably applied to a siding board sealing material that is used outdoors and is required to have heat resistance and water resistance against rainwater and the like. Further, the sealing material according to the present embodiment is preferably used as a sealing material for a ceramic siding board, which is a porous material that easily absorbs water because the decrease in adhesiveness due to moisture entering the ceramic siding board is small. Can be done.

Hereinafter, the wall having the joint structure according to the present embodiment will be described in detail with reference to Examples.

(Synthesis Example 1: Crosslinkable Silicon Group-Containing Organic Polymer with Number Average Molecular Weight of 15,000 or More)
Using propylene glycol as an initiator, propylene oxide was reacted in the presence of a zinc hexacyanocobaltate-glime complex catalyst to obtain hydroxyl-terminated polyoxypropylene having a number average molecular weight of 29,000. A methanol solution of NaOCH ₃ was added to this hydroxyl group-terminated polyoxypropylene polymer to distill off methanol, and allyl chloride was further added to convert the terminal hydroxyl group into an allyl group. After desalting and purification treatment, the hydrosilyl compound methyldimethoxysilane is reacted in the presence of a platinum catalyst to have a methyldimethoxysilyl group at the terminal and an average of 1.3 crosslinkable silicon groups in one molecule. A polymer (1) having an average molecular weight of 29,000 was obtained. The number average molecular weight is a polystyrene-equivalent molecular weight measured by gel permeation chromatography using HLC-8120GPC manufactured by Tosoh as a liquid feeding system, TSK-GELH type manufactured by Tosoh as a column, and THF as a solvent.

(Synthesis Example 2: Crosslinkable Silicon Group-Containing Organic Polymer with Number Average Molecular Weight of 15,000 or More)
Using propylene glycol as an initiator, propylene oxide was reacted in the presence of a zinc hexacyanocobaltate-glime complex catalyst to obtain hydroxyl-terminated polyoxypropylene having a number average molecular weight of 16,000. A methanol solution of NaOCH ₃ was added to this hydroxyl group-terminated polyoxypropylene polymer to distill off methanol, and allyl chloride was further added to convert the terminal hydroxyl group into an allyl group. After desalting and purification treatment, the hydrosilyl compound methyldimethoxysilane is reacted in the presence of a platinum catalyst to have a methyldimethoxysilyl group at the terminal and an average of 1.6 crosslinkable silicon groups in one molecule. A polymer (2) having an average molecular weight of 16,000 was obtained.

(Examples 1 to 4)
A one-component sealant composition was prepared with the composition shown in Table 1, and a test sample using this sealant composition was prepared. Using this test sample, the tensile properties (50% tensile modulus, breaking strength, elongation at break, breaking state) were measured at the initial stage, after immersion in water, and after heat exposure. The results are shown in Table 1. The composition and test sample preparation and test method are as follows.

The polymers (1) and polymers (2) obtained in Synthesis Example 1 and Synthesis Example 2 as oxyalkylene polymers having a crosslinkable silicon group of the component (A) shown in Table 1 and having a number average molecular weight of 15,000 or more. ), Filler, plasticizer, dehydrating agent, silanol condensation catalyst, and diluent were blended in parts by mass shown in Table 1, and heated / reduced pressure mixing / stirring was performed at 110 ° C. for 2 hours to dehydrate the blended substance. .. Further, a predetermined amount of the polyfunctional epoxy resin of the component (B), the ketimine of the component (C), and the curing catalyst were added, and the mixture was stirred and mixed to prepare a sealing material composition.

In Table 1, the blending amount of each compounding substance is shown by mass. Details of each compounded substance are as follows.
* 1 Bisphenol A diglycidyl ether (manufactured by Mitsubishi Chemical Corporation, JER828)
* 2 Condensation of stearylamine and MIBK * 3 Di2-ethylhexyl epoxyhexahydrophthalate (manufactured by New Japan Chemical Co., Ltd., Sansosizer E-PS)
* 4 Fatty acid-treated heavy calcium carbonate (manufactured by Maruo Calcium Co., Ltd., MC coat S-1)
* 5 Fatty acid-treated colloidal calcium carbonate (Maruo Calcium Co., Ltd., Calfine 500)
* 6 Non-functional acrylic polymer, weight average molecular weight 2500 (manufactured by Toagosei Co., Ltd., ARUFON UP-1110)
* 7 Vinyl trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM1003)
* 8 Dibutyltin diacetylacetonate (manufactured by Nitto Kasei Co., Ltd., Neneostane U-220H)
* 9 Normal paraffin [main component, n-undecane] (manufactured by Japan Energy Co., Ltd., Cactus normal paraffin N-11)

(Creation of test sample)
In accordance with the siding sealant standard, the I-type test piece described in 5.1.6 of the standard was prepared. Cut a ceramic siding board (Nichiha wood fiber reinforced cement board, Moen siding M. Thickness 14 mm) to a size of 50 mm in length and 50 mm in width, and cut the two siding boards so that they face each other in the vertical direction at an interval of 10 mm. Fixed to. A foamed polyethylene backup material having a length of 50 mm, a width of 10 mm, and a thickness of 6 mm was placed on the lower surface of the gap, and the surface of the siding board was covered with masking tape. After filling the gap (joint) with an interval of 10 mm to a thickness of 8 mm without applying a primer, the masking tape is removed, and pre-curing is performed in a 23 ° C. and 50% RH environment for 1 week, and then After 1 week of curing in an environment of 30 ° C. to cure the sealant, the backup material was removed to prepare a test sample.

(Water immersion test)
After immersing the test sample in pure water at 23 ° C. for 7 days, the water on the surface was wiped off and the tensile properties were measured.

(Heat exposure test)
The test sample was heated in an oven at 80 ° C. for 14 days, cooled to room temperature, and then the tensile properties were measured.

(Tensile adhesiveness measurement method)
A tensile adhesiveness test was carried out in accordance with the siding sealant standard (test temperature 23 ° C.). After the completion of each curing, a tensile adhesiveness test was carried out in an environment of 23 ° C. at a tensile speed of 50 mm / min. Then, the load when the elongation rate was 50% and the maximum load and the amount of elongation at the maximum load were measured. Furthermore, the measurement results were evaluated based on the following criteria.

(initial)
The modulus, modulus at 50% elongation, in the case of 0.2 N / mm ² or less "◎", of less than 0.4 N / mm ² exceeding 0.2 "○", 0.4 N / mm ² In the above cases, it was evaluated as "x".
The elongation rate at the maximum load was evaluated as "⊚" when the elongation rate at the maximum load was 250% or more, "◯" when it was 150 or more and less than 250%, and "x" when it was less than 150%.

(After soaking in water)
Regarding the modulus, the modulus at 50% elongation and the rate of change [(modulus at 50% elongation after immersion in water) / (modulus at initial 50% elongation) x 100] have a modulus of 0.2 N / mm. If the rate of change is less than or equal to 100% in ² or less "◎", modulus of 0.4N / mm ² less than in the rate of change is less than 150% (however, modulus at 0.2N / mm ² or less, the rate of change is 100% In the case of (excluding the following), it was evaluated as "◯", and when the modulus was 0.4 N / mm ² or more and the rate of change was 150% or more, it was evaluated as "x".
Regarding the elongation rate at maximum load, the elongation rate at maximum load and its rate of change [(extension rate at maximum load after immersion in water) / (extension rate at initial maximum load) x 100] are the elongation rates. When is 250% or more and the rate of change is 100% or more, "◎", when the elongation rate is 150% or more and the rate of change is 75% or more (however, except when the elongation rate is 250% or more and the rate of change is 100% or more) The case was evaluated as “◯”, and the case where the elongation rate was less than 150% and the rate of change was less than 75% was evaluated as “x”.

(After heating)
Regarding the modulus, the modulus at 50% elongation and the rate of change [(modulus at 50% elongation after heating) / (modulus at initial 50% elongation) x 100] have a modulus of 0.3 N / mm ^2. If the rate of change of 150% or less in the "◎", modulus change rate is 200% or less is less than 0.4 N / mm ² (where the modulus is 0.3 N / mm ² or less in change rate of not more than 150% In the case of (excluding)), it was evaluated as “◯”, and when the modulus was 0.4 N / mm ² or more and the rate of change exceeded 200%, it was evaluated as “x”.
Regarding the elongation rate at maximum load, the elongation rate at maximum load and its rate of change [(extension rate at maximum load after heating) / (extension rate at initial maximum load) x 100] are the elongation rates. When the rate of change is 250% or more and the rate of change is 100% or more, "◎", when the rate of elongation is 150% or more and the rate of change is 75% or more (excluding the rate of elongation of 250% or more and the rate of change of 100% or more) "○", when the elongation rate was less than 150% and the rate of change was less than 75%, it was evaluated as "x".

As shown in Table 1, in Examples 1 to 4, the rate of change of the modulus at 50% elongation after immersion in water is as small as about 60% or less, and the elongation rate at maximum load after heating is also about 200% or more. It was shown to have excellent properties.

Further, as is clear from Examples 3 to 4 in which the monofunctional epoxy compounds 3 and 10 parts by mass are further added to Examples 1 and 2, the organic polymer having a crosslinkable silicon group is added to the epoxy resin to further crosslinkability. The sealant composition, to which a ketimine compound having no silicon group was added and a monofunctional epoxy compound was further added, improved the initial 50% modulus and the elongation at maximum load, and 50% after heating. It was shown that both the elongation modulus and the elongation rate at maximum load were improved. As described above, it was shown that the cured product of the sealant composition according to the examples has excellent water resistance and heat resistance.

Although the embodiments and examples of the present invention have been described above, the embodiments and examples described above do not limit the invention according to the claims. In addition, not all combinations of features described in the embodiments and examples are indispensable for the means for solving the problems of the invention, and various as long as they do not deviate from the technical idea of the present invention. It should be noted that it can be transformed.

1 Wall with joint structure 10 First adherend 12 Second adherend 20 Sealant 30 Primer layer 40 Backup material

Claims (7)

A wall with a joint structure of a structure
The first adherend and
With the second adherends arranged at positions adjacent to each other with a gap between them and the first adherends.
JTC S-0001 Ceramic siding sealant filled in the gap In the tensile adhesiveness test results tested in accordance with the JTC standard, the rate of change of modulus during 50% elongation after heating was 200% or less, and heating was performed. It is equipped with a one-component room temperature moisture-curable sealant having a rate of change in elongation at maximum load of 75% or more after immersion in water and a rate of change in elongation at maximum load of 75% or more after immersion in water .
The one-component room temperature humidity curing type sealing material is
(A) A crosslinkable silicon group-containing organic polymer having a number average molecular weight of 15,000 or more,
(B) A compound having two or more epoxy groups in the molecule,
(C) Containing with a ketimine compound having no crosslinkable silicon group ,
(C) A wall having a joint structure obtained by curing a one-component room temperature moisture-curable sealant composition in which a ketimine compound having no crosslinkable silicon group is a ketimine monoamine . The wall having the joint structure according to claim 1, wherein the one-component room temperature moisture-curable sealant composition further contains (D) a monofunctional epoxy compound. A backup material for loading a backup material in the gap between the first adherend and the second adherend arranged adjacent to each other with a gap between the first adherend. Loading process and
In the tensile adhesiveness test result in which the gap on the backup material was tested in accordance with the JTC S-0001 ceramic siding sealant JTC standard, the rate of change of the modulus during 50% elongation after heating was 200% or less. A one-component room temperature moisture-curable sealant composition in which the rate of change of the elongation rate at the maximum load after heating is 75% or more, and the rate of change of the elongation rate at the maximum load after immersion in water is 75% or more . in a filling step of filling,
The one-component room temperature humidity curing type sealing material is
(A) A crosslinkable silicon group-containing organic polymer having a number average molecular weight of 15,000 or more,
(B) A compound having two or more epoxy groups in the molecule,
(C) With a ketimine compound having no crosslinkable silicon group
Contains,
Wherein (C) a ketimine compound having no crosslinkable silicon group, Oh Ru joint construction methods ketimine monoamine. The one-component room temperature humidity curing type sealing material obtained by curing the one-component room temperature moisture curing type sealing material is
JTC S-0001 Ceramic siding sealant In the tensile adhesiveness test results tested in accordance with the JTC standard,
The elongation rate at maximum load after immersion in water is 150% or more .
At the time of 50% elongation modulus after vulcanizing heat is less than 0.4 N / mm ^2,
Joint construction method according to claim 3 maximum load when the elongation rate after pressurization heat is 150% or more. The JTC S- is filled in the gap between the first adherend and the second adherend arranged adjacent to each other with a gap between the first adherend. 0001 Ceramic siding sealant In the tensile adhesiveness test results tested in accordance with the JTC standard, the rate of change of the modulus at 50% elongation after heating is 200% or less, and the elongation rate at maximum load after heating is A one-component room temperature moisture-curable sealant composition having a rate of change of 75% or more and a rate of change of elongation at maximum load after immersion in water of 75% or more .
(A) A crosslinkable silicon group-containing organic polymer having a number average molecular weight of 15,000 or more,
(B) A compound having two or more epoxy groups in the molecule,
(C) Containing with a ketimine compound having no crosslinkable silicon group ,
The (C) ketimine compound having no crosslinkable silicon group is a ketimine monoamine.
The cured product of the one-component room temperature moisture-curable sealant composition is
JTC S-0001 Ceramic Siding Sealant Composition of one-component room temperature moisture-curable sealant with initial 50% tensile modulus less than 0.4 N / mm ² in the tensile adhesiveness test results tested in accordance with JTC standards. object. The cured product of the one-component room temperature moisture-curable sealant composition is
JTC S-0001 Ceramic siding sealant The one-component room temperature moisture curing type according to claim 5, wherein the 50% tensile modulus after the heat exposure acceleration test tested in accordance with the JTC standard is less than 0.4 N / mm ^2. Sealant composition. (D) The one-component room temperature moisture-curable sealant composition according to claim 5 or 6, further containing a monofunctional epoxy compound.