Room temperature-curable organopolysiloxane composition

Abstract

To provide a room temperature-curable organopolysiloxane composition having excellent storage stability in a sealed packaging form and having less odor.SOLUTION: There is provided a room temperature-curable organopolysiloxane composition comprising the following components (A), (B), (C), and (D): (A) a diorganopolysiloxane having a viscosity of 20-1,000,000 mPa s at 25°C; (B) an alkoxy or enoxysilane compound in which a functional group bonded to a silicon atom is a hydrocarbon group that does not contain a heteroatom other than an oxygen atom, and / or a partially hydrolyzed condensate thereof; (C) a curing catalyst; and (D) an organosilicon compound.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a room-temperature-curable organopolysiloxane composition that cures at room temperature to form a silicone rubber. Specifically, the present invention relates to a room-temperature-curable organopolysiloxane composition that, after curing, provides a silicone rubber that has excellent self-adhesion to glass, various metals, resins, etc., and that has excellent storage stability, particularly when packaged in a sealed container, and has a low odor. [Background technology]

[0002] Among the organopolysiloxane compositions that cure at room temperature to form rubber-like elastomers, so-called one-component (single-liquid) room-temperature-curable organopolysiloxane compositions undergo a curing reaction upon contact with moisture in the air. These room-temperature-curable organopolysiloxane compositions eliminate the need for complicated weighing and mixing of base polymers, crosslinkers, catalysts, etc. immediately before use, eliminating the risk of formulation errors. Furthermore, they generally exhibit excellent adhesion to a wide range of substrates, even without the use of a primer. For this reason, these room-temperature-curable organopolysiloxane compositions are widely used as elastic adhesives and coating materials in the electrical and electronics industries, as well as in construction sealants.

[0003] Such one-component room-temperature-curable organopolysiloxane compositions are often classified by the compounds released from the composition upon contact with moisture in the air, and representative examples include deacetic acid, deoxime, deamidation, dehydroxylamine, deacetone, and dealcohol-curing organopolysiloxane compositions. Among these, dealcohol-curing organopolysiloxane compositions that cure by releasing alcohol are particularly preferred for their low odor, non-corrosion to metals such as copper and iron, excellent self-adhesion (adhesion to various substrates after curing when no primer is used), and excellent adhesion durability.

[0004] However, although one-component dealcohol-type organopolysiloxane compositions have the above-mentioned excellent properties for a short period after production, they have drawbacks in storage stability, such as losing the properties they had immediately after production over time during storage, depending on the formulation. Furthermore, storage in direct sunlight at the site of use or in high-temperature environments exceeding 40°C, which often occurs when stored in a container during transport, can cause problems such as a loss of the original properties or poor curing, even for a relatively short period of time.

[0005] One-component, dealcohol-removing organopolysiloxane compositions have long been proposed, and Japanese Patent Publication No. 39-27643 (Patent Document 1) proposes a composition comprising a terminally hydroxyl-blocked organopolysiloxane, an alkoxysilane, and a titanium compound. Furthermore, Japanese Patent Application Laid-Open No. 55-43119 (Patent Document 2) proposes a composition comprising an organopolysiloxane having an alkoxysiloxy group at its terminal, an alkoxysilane, and an alkoxytitanium. However, when calcium carbonate is blended into these compositions to impart good physical properties to the sealant, storage stability is not achieved, and there are problems such as the composition not achieving the desired properties when used after long-term storage, or the composition not curing when stored in a high-temperature environment exceeding 50°C.

[0006] U.S. Patent No. 4,417,042 (Patent Document 3) proposes a composition that improves storage stability by using a scavenger with an organosilazane structure to capture alcohol compounds within the composition. This technology improves storage stability, particularly when hexamethyldisilazane is selected as the scavenger. However, because hexamethyldisilazane has a low boiling point, is highly volatile, and has a pungent odor, compositions containing it also produce a strong odor. In addition, ammonia and trimethylmethoxysilane are by-produced during alcohol capture, resulting in an even stronger odor over time, compromising the low odor that is an advantage of dealcohol-free compositions. Furthermore, when a high-boiling silazane such as a cyclic silazane is used, the odor problem caused by the by-products of ammonia and low-boiling alkoxysilanes cannot be solved. Furthermore, since cyclic silazanes are expensive, there is also the problem of high industrial costs.

[0007] Japanese Patent Publication No. 7-39547 (Patent Document 4) proposes a composition that has excellent storage stability when sealed. The composition proposed here requires the use of a polymer in which an alkoxysilyl alkylene group is modified at the end of an organopolysiloxane, and the preparation of this polymer raises problems such as high industrial costs.

[0008] Furthermore, Japanese Patent Laid-Open No. 2-38309 (Patent Document 5) and Japanese Patent Laid-Open No. 2003-176411 (Patent Document 6) propose compositions using calcium carbonate treated with a fatty acid ester. These compositions have problems such as insufficient storage stability when stored at high temperatures exceeding 50°C, and because calcium carbonate treated with a fatty acid ester is used as a special filler, compositions containing a large amount of this filler are expensive. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Special Publication No. 39-27643 [Patent Document 2] Japanese Patent Application Publication No. 55-43119 [Patent Document 3] U.S. Patent No. 4,417,042 [Patent Document 4] Special Publication No. 7-39547 [Patent Document 5] Japanese Patent Application Publication No. 2-38309 [Patent Document 6] Japanese Patent Application Laid-Open No. 2003-176411 Summary of the Invention [Problem to be solved by the invention]

[0010] Accordingly, an object of the present invention is to provide a dealcohol-curable room-temperature organopolysiloxane composition that cures at room temperature in the presence of atmospheric moisture to give a cured silicone rubber product, and in particular to provide a room-temperature curable organopolysiloxane composition that has excellent storage stability when packaged in a sealed container and has little odor. [Means for solving the problem]

[0011] As a result of extensive research conducted by the present inventors to achieve the above object, they discovered that an organopolysiloxane composition having a specific composition can solve the above problems, and thus completed the present invention. That is, the present invention provides the following room-temperature-curable organopolysiloxane composition.

[0012] [1] A room-temperature-curable organopolysiloxane composition comprising the following components (A), (B), (C), and (D): (A) 100 parts by mass of a diorganopolysiloxane represented by the following general formula (1) having a viscosity at 25°C of 20 to 1,000,000 mPa·s: [ka] (In formula (1), R 1 are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms, and R 2 are independently a group having 1 to 10 carbon atoms selected from a monovalent hydrocarbon group, a halogenated monovalent hydrocarbon group, and a cyanoalkyl group. 1 is a hydrogen atom, the value is 2, and R 1 is 0 or 1 when it is an alkyl group having 1 to 10 carbon atoms or an alkoxyalkyl group having 2 to 10 carbon atoms. Y is an oxygen atom, a divalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following general formula (2). n is a number that gives the diorganopolysiloxane a viscosity at 25°C of 20 to 1,000,000 mPa s. [ka] (In formula (2), R 2 are independently a group having 1 to 10 carbon atoms selected from monovalent hydrocarbon groups, halogenated monovalent hydrocarbon groups, and cyanoalkyl groups, and Z is a divalent hydrocarbon group having 1 to 6 carbon atoms. (B) an alkoxy or enoxy silane compound and / or a partial hydrolysis condensate thereof, in which the functional group bonded to a silicon atom is a hydrocarbon group containing no heteroatoms other than oxygen atoms: 0.5 to 20 parts by mass (C) Curing catalyst: 0.001~20 parts by mass (D) an organosilicon compound represented by the following general formula (3): 0.1 to 5 parts by mass [ka] (In formula (3), R 1 are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms, and R 2 are independently a group having 1 to 10 carbon atoms selected from a monovalent hydrocarbon group, a halogenated monovalent hydrocarbon group, and a cyanoalkyl group; R 3 are independently an alkylene group having 1 to 10 carbon atoms, and m is a number from 1 to 3. [2] The room-temperature-curable organopolysiloxane composition according to [1], wherein component (C) is a tin compound. [3] The room-temperature-curable organopolysiloxane composition according to [1] or [2], further comprising 1 to 300 parts by mass of (E) an inorganic filler per 100 parts by mass of component (A). [4] The room-temperature-curable organopolysiloxane composition according to any one of [1] to [3], further comprising (F) a silane coupling agent in an amount of 0.1 to 20 parts by mass per 100 parts by mass of the component (A). [5] The room-temperature-curable organopolysiloxane composition according to any one of [1] to [4], which is filled in a cartridge made of polyethylene and / or polypropylene. [Effects of the Invention]

[0013] The room-temperature-curable organopolysiloxane composition of the present invention has excellent storage stability when packaged in a sealed container, has little odor, and after curing gives a cured product that has excellent adhesion to glass, painted aluminum, and the like, even without the use of a primer, making it useful as a coating material, sealant, and adhesive. DETAILED DESCRIPTION OF THE INVENTION

[0014] The room-temperature-curable organopolysiloxane composition of the present invention comprises the following components (A), (B), (C), and (D).

[0015] Component (A) The diorganopolysiloxane of component (A) is the main component of the composition and is a diorganopolysiloxane represented by the following general formula (1) which has hydroxy groups, alkoxy groups, or alkoxyalkoxy groups at both molecular chain terminals. Furthermore, if the viscosity is too low, the rubber elasticity after curing will be poor, and if it is too high, workability will be reduced, so the viscosity at 25°C must be in the range of 20 to 1,000,000 mPa·s, and preferably in the range of 100 to 100,000 mPa·s. Note that this viscosity is measured using a rotational viscometer at 25°C. The molecular structure of this organopolysiloxane is substantially linear, that is, the structure of the siloxane bond chain made of SiO is linear, but part of the molecular chain, such as the alkyl group that is the side chain, may be branched. [ka] (In formula (1), R 1 are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms, and R 2are independently a group having 1 to 10 carbon atoms selected from a monovalent hydrocarbon group, a halogenated monovalent hydrocarbon group, and a cyanoalkyl group. 1 is a hydrogen atom, the value is 2, and R 1 is 0 or 1 when it is an alkyl group having 1 to 10 carbon atoms or an alkoxyalkyl group having 2 to 10 carbon atoms. Y is an oxygen atom, a divalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following general formula (2). n is a number that gives the diorganopolysiloxane a viscosity at 25°C of 20 to 1,000,000 mPa s.

[0016] In formula (1), R 1 Examples of the alkyl group include a hydrogen atom, an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, and an octyl group; and an alkoxyalkyl group having 2 to 10 carbon atoms such as a methoxymethyl group, a methoxyethyl group, and an ethoxymethyl group. Of these, a hydrogen atom, a methyl group, or an ethyl group is preferred.

[0017] In formula (1), R 2 Examples of the alkyl group include groups having 1 to 10 carbon atoms selected from monovalent hydrocarbon groups, halogenated monovalent hydrocarbon groups, and cyanoalkyl groups. Examples of monovalent hydrocarbon groups include alkyl groups such as methyl, ethyl, propyl, butyl, and octyl; cycloalkyl groups such as cyclopentyl and cyclohexyl; alkenyl groups such as vinyl and allyl; aryl groups such as phenyl, tolyl, and naphthyl; and aralkyl groups such as benzyl, phenylethyl, and phenylpropyl. Examples of halogenated monovalent hydrocarbon groups include trifluoropropyl and chloropropyl. Examples of cyanoalkyl groups include β-cyanoethyl and γ-cyanopropyl. Of these, a methyl group is preferred.

[0018] a is R 1 is a hydrogen atom, the value is 2, and R 1 is 0 or 1 when it is an alkyl group having 1 to 10 carbon atoms or an alkoxyalkyl group having 2 to 10 carbon atoms.

[0019] In formula (1), Y is an oxygen atom, a divalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following general formula (2). The divalent hydrocarbon group having 1 to 6 carbon atoms is preferably an alkylene group having 1 to 6 carbon atoms, such as methylene, ethylene, propylene, butylene, or hexene, with ethylene being particularly preferred. The hydrogen atom of the alkylene group may be substituted with a monovalent hydrocarbon group, such as a methyl group. [ka] (In formula (2), R 2 are independently a group having 1 to 10 carbon atoms selected from monovalent hydrocarbon groups, halogenated monovalent hydrocarbon groups, and cyanoalkyl groups, and Z is a divalent hydrocarbon group having 1 to 6 carbon atoms.

[0020] In formula (2), R 2 is R in equation (1). 2 The same can be mentioned. In formula (2), the divalent hydrocarbon group is preferably an alkylene group having 1 to 6 carbon atoms, such as methylene, ethylene, propylene, butylene, or hexene, with ethylene being particularly preferred. The hydrogen atom of the alkylene group may be substituted with a monovalent hydrocarbon group, such as methyl.

[0021] In formula (1), n ​​is a number that gives a viscosity at 25°C of 20 to 1,000,000 mPa·s. The component (A) may be used alone or in combination of two or more types. Component (A) can be produced by a known method.

[0022] The content of component (A) in the entire composition of the present invention is preferably from 20 to 95 mass %, more preferably from 30 to 90 mass %.

[0023] (B) Component Component (B) is an alkoxy or enoxy silane compound and / or a partial hydrolysis condensate thereof, in which the functional group bonded to the silicon atom is a hydrocarbon group that does not contain heteroatoms such as nitrogen (N) or sulfur (S) other than oxygen (O), and serves to cure the room-temperature-curable organopolysiloxane composition of the present invention and to adjust the curing rate by adjusting the amount added. Furthermore, component (B) is preferably one in which the functional group bonded to the silicon atom, other than the alkoxy or enoxy group, does not contain heteroatoms such as oxygen (O), nitrogen (N), or sulfur (S).

[0024] Examples of the alkoxy or enoxy silane of component (B) include alkoxy group-containing compounds such as tetramethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, isobutyltrimethoxysilane, normal butyltrimethoxysilane, normal hexyltrimethoxysilane, decyltrimethoxysilane, and partial hydrolysis condensates thereof; substituted alkoxy group-containing compounds such as tetrakis(2-ethoxyethoxy)silane, methyltris(2-methoxyethoxy)silane, vinyl(2-ethoxyethoxy)silane, phenyltris(2-methoxyethoxy)silane, and partial hydrolysis condensates thereof; methyltriisopropenoxysilane, vinyltriisopropenoxysilane, phenyltris(2-methoxyethoxy)silane, and partial hydrolysis condensates thereof; enoxy group-containing compounds such as phenyltriisopropenoxysilane, dimethyldiisopropenoxysilane, methylvinyldiisopropenoxysilane, and their partial hydrolysis condensates, 1,3-bis[(trimethoxysilyl)ethyl]-1,1,3,3-tetramethyldisiloxane, 1,3-bis[(triethoxysilyl)ethyl]-1,1,3,3-tetramethyldisiloxane, 1,3-bis[(methyldimethoxysilyl)ethyl]-1,1,3,3-tetramethyldisiloxane, Examples of the alkoxysilylsiloxane include bisalkoxysilyldisiloxane compounds such as 1-[(trimethoxysilyl)ethyl]-3-[(triethoxysilyl)ethyl]-1,1,3,3-tetramethyldisiloxane and 1-[(methyldimethoxysilyl)ethyl]-3-[(trimethoxysilyl)ethyl]-1,1,3,3-tetramethyldisiloxane, and bisalkoxysilylalkane compounds such as 1,2-bis(trimethoxysilyl)ethane and 1,6-bis(trimethoxysilyl)hexane.

[0025] In the present invention, the alkoxy or enoxy silane may be used alone or in combination of two or more. Among them, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, isobutyltrimethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane, which can be obtained industrially at relatively low cost, are preferred, and methyltrimethoxysilane is particularly preferred.

[0026] The amount of component (B) blended is 0.5 to 20 parts by mass, and preferably 0.5 to 15 parts by mass, per 100 parts by mass of component (A). 1 When is a hydrogen atom, in order to obtain good curability and storage stability, the number of moles of alkoxy groups in component (B) per mole of hydroxyl groups in component (A) is preferably more than 1 mol, and more preferably 2 to 30 mol.

[0027] (C) Component Component (C) is a curing catalyst, and examples of the curing catalyst include organic carboxylates, alkoxides, and chelate compounds of metals such as tin, aluminum, zirconium, titanium, iron, antimony, bismuth, and manganese. More specifically, these include tin compounds such as dibutyltin dilaurate, dibutyltin dioctoate, dioctyltin dilaurate, dibutyltin maleate ester, dimethyltin dineodecanoate, dibutyltin dimethoxide, dioctyltin dineodecanoate, and stannous octoate; organic aluminum compounds such as aluminum tris(acetylacetonate), aluminum tris(ethylacetoacetate), diisopropoxyaluminum ethylacetoacetate, and triethoxyaluminum; zirconium tetrakis(acetylacetonate), tetraisopropoxyzirconium, tetrabutoxyzirconium, and tributoxyzirconium acetone. Examples include organic zirconium compounds such as tetra-normal-butoxytitanium, tetrakis(2-ethylhexoxy)titanium, tetraisopropoxytitanium, and tetra-tertiary-butoxytitanium; titanium chelate compounds such as diisopropoxybis(acetylacetonato)titanium, diisopropoxybis(ethylacetoacetate)titanium, and dibutoxybis(methylacetoacetate)titanium; and amine compounds such as dibutylamine, laurylamine, tetramethylguanidine, and tetramethylguanidylpropyltrimethoxysilane, as well as salts thereof. These compounds can be used singly or in combination of two or more. It is preferable to add a tin compound or a titanium compound, and of these, a tin compound is preferred, as these compounds provide the composition of the present invention with excellent properties such as appearance and storage stability. The amount of component (C) added is 0.001 to 20 parts by mass, preferably 0.01 to 10 parts by mass, per 100 parts by mass of component (A).

[0028] (D) Component Component (D) is an organosilicon compound represented by the following formula (3). [ka] (In formula (3), R 1 are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms, and R 2 are independently a group having 1 to 10 carbon atoms selected from a monovalent hydrocarbon group, a halogenated monovalent hydrocarbon group, and a cyanoalkyl group; R 3 are independently an alkylene group having 1 to 10 carbon atoms, and m is a number from 1 to 3.

[0029] In formula (3), R 1 and R 2 are R in Equation (1), respectively. 1 and R 2 The same can be mentioned. In formula (3), R 3 are independently an alkylene group having 1 to 10 carbon atoms such as a methylene group, a dimethylene group, a trimethylene group, or a butylene group, and among these, a methylene group, a dimethylene group, or a trimethylene group is preferred.

[0030] Specific examples of component (D) include the following: [ka]

[0031] The amount of component (D) added is 0.1 to 5 parts by mass, and preferably 0.2 to 3 parts by mass, per 100 parts by mass of component (A). If the amount is less than 0.1 part by mass, the composition will not have sufficient storage stability, while if it exceeds 5 parts by mass, the self-adhesiveness of the composition may decrease.

[0032] (E) Component In addition to the above-described components (A) to (D), the composition of the present invention may also contain an inorganic filler (E). Component (E) serves to impart good mechanical properties to the cured product of the composition of the present invention.

[0033] Examples of component (E) include wet silica, fumed silica produced by a dry method, silicas whose surfaces have been treated with chlorosilanes such as dichlorodimethylsilane and trichloromethylsilane, silazanes such as hexamethyldisilazane, or siloxanes such as octamethyltetrasiloxane, heavy (or crushed) calcium carbonate, precipitated calcium carbonate, and powders of these calcium carbonates whose surfaces have been treated with organic acids such as fatty acids and resin acids, alkali metal salts of organic acids, organic acid esters, or the like. In the present invention, there are no limitations on whether or not a surface treatment is performed, and the type of treatment agent. Inorganic fillers such as fumed silica, precipitated calcium carbonate, heavy calcium carbonate, alumina, and aluminum hydroxide can be used alone or in combination of two or more types, depending on the desired properties of the composition. The BET specific surface area of ​​component (E) is not particularly limited, but for fumed silica, it is 30 to 400 m 2 / g, and in the case of calcium carbonate obtained by treating the surface of precipitated calcium carbonate with various organic substances, it is preferably 5 to 50 m 2 / g, and particularly preferably 10 to 40m 2 / g. The calcium carbonate of the precipitated calcium carbonate without surface treatment has agglomerated during the manufacturing process and has spindle-shaped primary particles, preferably 1 to 20 mm. 2 / g, particularly preferably 3 to 10m 2 / g. The heavy calcium carbonate, both those with no surface treatment and those with the surface treated with an organic substance, is preferably 1 to 15 m 2 / g.

[0034] When component (E) is added, the blending amount is preferably in the range of 1 to 300 parts by mass, more preferably 5 to 200 parts by mass, per 100 parts by mass of component (A). If the blending amount of component (E) is less than the lower limit of the above range, the properties of component (E) may not be obtained, whereas if the blending amount exceeds the upper limit of the above range, the handling and workability of the composition of the present invention may be impaired.

[0035] (F) Component In addition to the above-described components (A) to (E), the composition of the present invention may contain a silane coupling agent (F), which further improves the adhesion of the composition of the present invention to various substrates.

[0036] Component (F) is a compound other than components (B) and (D), and is preferably a compound known in the art. In particular, compounds having an alkoxysilyl group or an alkenoxysilyl group as a hydrolyzable group are preferred, such as γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 3-(N-aminomethylbenzylamino)propyltrimethoxysilane, 3-(N-aminomethylbenzylamino)propyltrimethoxysilane, 3-(N-aminomethylbenzylamino)propyltriethoxy ... Examples include methoxysilane, N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine, N,N-bis[3-(trimethoxysilyl)propyl]amine, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltriisopropenoxysilane, γ-glycidoxypropylmethyldiisopropenoxysilane, a reaction product of a (meth)acrylic silane and an aminosilane, a reaction product of an epoxy silane and an aminosilane, a reaction product of an aminosilane and a silane containing a halogenated alkyl group, etc. In particular, it is preferable to use a silane coupling agent containing at least one amino group in the molecule.

[0037] When this silane coupling agent is added, the blending amount is preferably 0.1 to 20 parts by mass, and particularly preferably 0.5 to 10 parts by mass, per 100 parts by mass of component (A). Less than 0.1 part by mass does not achieve the improvement in adhesion achieved by adding component (F), while more than 20 parts by mass is not only uneconomical in terms of cost but may also result in a decrease in hot water-resistant adhesion.

[0038] [Other ingredients] In addition to the above-mentioned components, commonly known additives may be used as long as they do not impair the effects of the present invention. Examples of additives include inorganic fillers other than component (E), such as dry process silica, wet process silica, fine quartz powder, titanium dioxide powder, diatomaceous earth powder, aluminum hydroxide powder, fine particle alumina, magnesia powder, zinc oxide powder, and fine powder-like inorganic fillers obtained by surface-treating these with silanes, silazanes, low-polymerization polysiloxanes, etc. The amount of such inorganic fillers added is 10 to 200 parts by mass, and preferably 30 to 150 parts by mass, per 100 parts by mass of component (A). Other additives include components for lowering the modulus of the silicone rubber after curing, such as dialkoxysilanes (e.g., diphenyldimethoxysilane, dimethyldimethoxysilane), dimethylpolysiloxanes capped at both ends with trimethylsiloxy groups, isoparaffin, platinum compounds as flame retardants, zinc carbonate powder, polyethers as thixotropy improvers as needed, colorants (e.g., pigments, dyes, fluorescent brighteners), heat resistance improvers (e.g., red iron oxide, cerium oxide), cold resistance improvers, rust inhibitors, mildew inhibitors, antibacterial agents, etc. In addition, solvents such as toluene, xylene, solvent volatile oil, cyclohexane, methylcyclohexane, and low-boiling point isoparaffin may also be added.

[0039] Manufacturing method The composition of the present invention can be produced as a so-called one-component, dealcohol-free organopolysiloxane composition by blending the above-described components (A) to (D), and, if necessary, component (E), component (F), and other components, in a dry atmosphere according to a conventional method. Thereafter, the composition is preferably stored in a sealed package. As a container for sealing and packaging, a cylindrical cartridge made of polyethylene or polypropylene is most preferred in order to maximize the effect of the composition of the present invention. The composition of the present invention usually cures in the presence of moisture in the air when left to stand in the air. The composition of the present invention can be used in a variety of applications, but is particularly useful as a coating material, a sealant, or an adhesive. [Example]

[0040] Examples, comparative examples, and synthesis examples of the present invention are described below, but the present invention is not limited to these examples. The viscosity values ​​in the examples are measured at 25°C using a rotational viscometer (TVB-10M manufactured by Toki Sangyo Co., Ltd.), and all parts mean parts by mass. All compositions of the present invention were prepared using a "mixing stirrer (model: 5DMV-01-r)" manufactured by Dalton Co., Ltd.

[0041] [Synthesis Example 1] In a 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel, and thermometer, 92.5 g (0.50 mol) of an organosilicon compound represented by the following formula (5), a toluene solution of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (0.5 × 10 platinum atoms) -5 mol) was added, and 122 g (1.00 mol) of trimethoxysilane was added dropwise over 1 hour at an internal temperature of 75 to 85°C. The mixture was then aged for 3 hours at 80°C. After aging, vacuum distillation was carried out to obtain 193 g of an organosilicon compound represented by the following formula (6). [ka]

[0042] [Synthesis Example 2] A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel, and thermometer was charged with 106 g (0.50 mol) of an organosilicon compound represented by the following formula (7) and a toluene solution of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (0.5 × 10 mol as platinum atoms), and 122 g (1.00 mol) of trimethoxysilane was added dropwise over 1 hour at an internal temperature of 75 to 85°C. The mixture was then aged for 3 hours at 80°C. After aging, vacuum distillation was performed to obtain 205 g of an organosilicon compound represented by the following formula (8). [ka]

[0043] [Example 1] 500 g (100 parts by mass) of dimethylpolysiloxane (viscosity 50,000 mPa s) in which both molecular chain terminals are blocked with dimethoxymethylsiloxy groups, 25 g (5 parts by mass) of methyltrimethoxysilane, 10 g (2 parts by mass) of vinyltrimethoxysilane, and 2.5 g (0.5 parts by mass) of 3-(2-aminoethylamino)propyltrimethoxysilane were mixed uniformly at a room temperature of 23°C under normal pressure for 10 minutes. After stopping the mixing, the mixture was allowed to stand for 18 hours in a sealed container at 23°C. After that, a polymer having a BET specific surface area of ​​105 m was obtained. 2 To this was added 70 g (14 parts by mass) of fumed silica (MU-215, manufactured by Shin-Etsu Chemical Co., Ltd.) having a surface treated with dimethyldichlorosilane (1 / g), and the mixture was mixed uniformly. Then, 200 g (40 parts by mass) of dimethylpolysiloxane (viscosity 100 mPa s) in which both molecular chain terminals were blocked with trimethylsiloxy groups, 8.5 g (1.7 parts by mass) of organosilicon compound 1 synthesized in Synthesis Example 1, and 1.5 g (0.3 parts by mass) of dioctyltin dineodecanoate were added, and the mixture was mixed under reduced pressure for 10 minutes while removing air bubbles until the mixture was uniform, yielding organopolysiloxane composition 1.

[0044] [Example 2] Organopolysiloxane composition 2 was obtained in the same manner as in Example 1, except that the amount of organosilicon compound 1 synthesized in Synthesis Example 1 added was changed from 8.5 g (1.7 parts by mass) to 4.0 g (0.8 parts by mass).

[0045] [Example 3] Organopolysiloxane composition 3 was obtained in the same manner as in Example 1, except that the organosilicon compound 1 synthesized in Synthesis Example 1 was replaced with the same amount of organosilicon compound 2 synthesized in Synthesis Example 2.

[0046] [Example 4] 500 g (100 parts by mass) of dimethylpolysiloxane (viscosity 50,000 mPa s) having one hydroxyl group (silanol group) bonded to a silicon atom at each end of the molecular chain, 25 g (5 parts by mass) of methyltrimethoxysilane, and 8.5 g (1.7 parts by mass) of 3-(2-aminoethylamino)propyltrimethoxysilane were mixed uniformly at room temperature of 23°C and atmospheric pressure for 10 minutes to prepare a mixture. After stopping the mixing, the mixture was allowed to stand for 18 hours in a sealed container at 23°C, and then the resulting mixture had a BET specific surface area of ​​150 m. 2 70 g (14 parts by mass) of 1 / g surface-untreated fumed silica ("Konasil-150" manufactured by OCI) was added and mixed uniformly, followed by addition of 200 g (40 parts by mass) of dimethylpolysiloxane (viscosity 100 mPa s) in which both molecular chain terminals were blocked with trimethylsiloxy groups, 8.5 g (1.7 parts by mass) of organosilicon compound 1 synthesized in Synthesis Example 1, 15 g (3 parts by mass) of a partial hydrolysis condensate of methyltrimethoxysilane, and 1.5 g (0.3 parts by mass) of dioctyltin dineodecanoate, and mixing was continued under reduced pressure for 10 minutes while removing air bubbles until the mixture was uniform, yielding organopolysiloxane composition 4.

[0047] [Comparative Example 1] 500 g (100 parts by mass) of dimethylpolysiloxane (viscosity 50,000 mPa s) having one hydroxyl group (silanol group) bonded to a silicon atom at each end of the molecular chain, 25 g (5 parts by mass) of methyltri(methylethylketoxime)silane, and 10 g (2 parts by mass) of vinyltri(methylethylketoxime)silane were mixed uniformly at room temperature of 23°C and atmospheric pressure for 10 minutes to prepare a mixture. After stopping the mixing, the mixture was allowed to stand for 18 hours in a sealed container at 23°C, and then the resulting mixture had a BET specific surface area of ​​105 m. 270 g (14 parts by mass) of fumed silica ("MU-215" manufactured by Shin-Etsu Chemical Co., Ltd.) surface-treated with 1 / g of dimethyldichlorosilane was added and mixed uniformly, followed by adding 200 g (40 parts by mass) of dimethylpolysiloxane (viscosity 100 mPa s) in which both molecular chain terminals were blocked with trimethylsiloxy groups, 4.0 g (0.8 parts by mass) of 3-(2-aminoethylamino)propyltrimethoxysilane, and 0.5 g (0.1 parts by mass) of dioctyltin dilaurate, and mixing was continued under reduced pressure for 10 minutes while removing air bubbles until the mixture was uniform, yielding organopolysiloxane composition 5.

[0048] Comparative Example 2 Organopolysiloxane composition 6 was obtained in the same manner as in Example 1, except that organosilicon compound 1 prepared in Synthesis Example 1 was not added.

[0049] Comparative Example 3 Organopolysiloxane Composition 7 was obtained in the same manner as in Example 1, except that in Example 4, the organosilicon compound 1 prepared in Synthesis Example 1 was replaced with the same amount of N,N-bis(trimethylsilyl)-3-aminopropyltrimethoxysilane.

[0050] Comparative Example 4 Organopolysiloxane composition 8 was obtained in the same manner as in Example 1, except that the organosilicon compound 1 prepared in Synthesis Example 1 was replaced with the same amount of hexamethyldisilazane.

[0051] Comparative Example 5 Organopolysiloxane Composition 9 was obtained in the same manner as in Comparative Example 4, except that the amount of hexamethyldisilazane added was 0.2 parts by mass.

[0052] Comparative Example 6 Organopolysiloxane composition 10 was obtained in the same manner as in Example 4, except that the organosilicon compound 1 prepared in Synthesis Example 1 was replaced with the same amount of hexamethyldisilazane.

[0053] The organopolysiloxane compositions prepared in the Examples and Comparative Examples were evaluated for physical properties, adhesion, and storage stability. Each evaluation was carried out according to the methods described below, and the results for the compositions obtained in the Examples and Comparative Examples are shown in Tables 1 and 2.

[0054] [Physical properties] The prepared composition was extruded into a polyethylene frame and left to cure for 7 days at a temperature of 23°C and a relative humidity of 50%, to prepare a 2 mm thick sheet. The physical properties of this sheet were measured in accordance with JIS K 6249.

[0055] [Odor] When extruding the product into a polyethylene frame for the evaluation of the "physical properties," the evaluator placed their nose 10 cm from the product and checked the odor for 20 seconds under conditions of a temperature of 23°C and a relative humidity of 50%. The odor level was evaluated on a six-point scale: "0" (odorless), "1" (barely detectable odor), "2" (weak odor that is recognizable), "3" (easily detectable odor), "4" (strong odor), and "5" (overpowering odor), with 0-2 being "low odor" and 3-5 being "unacceptable."

[0056] [Storage stability] The composition was placed in a cylindrical polyethylene sealant cartridge (330 ml capacity) and sealed with an inner stopper. This cartridge was stored for 28 days in a thermo-hygrostat chamber adjusted to a temperature of 70°C and a relative humidity of 20%, then removed and left for 1 day at a temperature of 23°C and a relative humidity of 50%. The stored composition was then evaluated for physical properties and odor. Regarding storage stability of the physical properties, a hardness that was less than ±5 points higher than the hardness before storage (immediately after preparation) was considered acceptable, and a hardness that was more than ±5 points higher than the hardness before storage (immediately after preparation) was considered unacceptable.

[0057] [Table 1]

[0058] [Table 2]

[0059] As can be seen from Tables 1 and 2, the organopolysiloxane compositions obtained in Examples 1 to 4 have low odor and exhibit excellent storage stability even when left under heated and humid conditions. Therefore, they are useful as waterproof sealants in construction and civil engineering applications, elastic adhesives and coating materials in the electrical and electronics industries, and the like.

Claims

1. A room-temperature-curable organopolysiloxane composition comprising the following components (A), (B), (C), and (D): (A) 100 parts by mass of a diorganopolysiloxane represented by the following general formula (1) having a viscosity at 25°C of 20 to 1,000,000 mPa·s: 【Chemistry 1】 (In formula (1), R 1 are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms, and R 2 are independently a group having 1 to 10 carbon atoms selected from monovalent hydrocarbon groups, halogenated monovalent hydrocarbon groups, and cyanoalkyl groups. 1 is a hydrogen atom, the value is 2, and R 1 is 0 or 1 when it is an alkyl group having 1 to 10 carbon atoms or an alkoxyalkyl group having 2 to 10 carbon atoms. Y is an oxygen atom, a divalent hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following general formula (2). n is a number that gives the diorganopolysiloxane a viscosity at 25°C of 20 to 1,000,000 mPa·s. 【Chemistry 2】 (In formula (2), R 2 are independently a group having 1 to 10 carbon atoms selected from a monovalent hydrocarbon group, a halogenated monovalent hydrocarbon group, and a cyanoalkyl group, and Z is a divalent hydrocarbon group having 1 to 6 carbon atoms. (B) an alkoxy or enoxy silane compound and / or a partial hydrolysis condensate thereof, in which the functional group bonded to a silicon atom is a hydrocarbon group containing no heteroatoms other than oxygen atoms: 0.5 to 20 parts by mass (C) Curing catalyst: 0.001 to 20 parts by mass (D) an organosilicon compound represented by the following general formula (3): 0.1 to 5 parts by mass 【Transformation 3】 (In formula (3), R 1 are independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms, and R 2 are independently a group having 1 to 10 carbon atoms selected from a monovalent hydrocarbon group, a halogenated monovalent hydrocarbon group, and a cyanoalkyl group; R 3 are independently an alkylene group having 1 to 10 carbon atoms, and m is a number from 1 to 3.

2. 2. The room-temperature-curable organopolysiloxane composition according to claim 1, wherein component (C) is a tin compound.

3. 2. The room-temperature-curable organopolysiloxane composition according to claim 1, further comprising 1 to 300 parts by weight of an inorganic filler (E) per 100 parts by weight of component (A).

4. 2. The room-temperature-curable organopolysiloxane composition according to claim 1, further comprising 0.1 to 20 parts by mass of a silane coupling agent (F) per 100 parts by mass of component (A).

5. 2. The room-temperature-curable organopolysiloxane composition according to claim 1, which is filled in a cartridge made of polyethylene and / or polypropylene.

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