JP5351482B2 - Room temperature curable organopolysiloxane composition - Google Patents

Description

  The present invention provides a dealcohol that becomes an adhesive rubber having excellent curability, high strength, high modulus, and excellent moisture resistance and hot water resistance by blending a specific long-chain alkyl group-containing siloxane compound. Type room temperature curable organopolysiloxane composition. The room temperature curable organopolysiloxane composition of the present invention is particularly suitably used for a multi-layer glass seal application.

  Conventionally composed of organopolysiloxane having a hydroxyl group at the molecular chain end, a reaction product or mixture of aminoalkylalkoxysilane and epoxyalkylalkoxysilane and a curing catalyst, and has adhesiveness to various substrates that are in contact during curing Organopolysiloxane compositions are known (Patent Document 1). However, the silicone rubber obtained by curing this composition has a drawback that its adhesive strength is reduced in a water-resistant adhesive property, particularly in a harsh environment such as hot water immersion in float glass.

Moreover, in order to improve water-resistant adhesion, it has been proposed to blend a disilaalkane compound (Patent Documents 2 and 3) or a specific methoxy group-containing silicon compound (Patent Document 4), but the effect is sufficient. I could not say.
Japanese Patent Publication No. 63-23226 JP-A 64-60656 JP 2003-221506 A JP 2007-119768 A

  The present invention provides a room temperature curable organopolysiloxane composition that improves the above-mentioned drawbacks of the prior art, has excellent curability, has a relatively high modulus, and is an adhesive rubber excellent in moisture resistance and warm water resistance. With the goal.

  As a result of intensive studies to achieve the above object, the present inventors have obtained a room temperature-curable organopolysiloxane composition having the above-mentioned excellent characteristics by blending a specific long-chain alkyl group-containing siloxane compound. The present invention has been completed.

That is, the present invention
(A) 100 parts by weight of a polyorganosiloxane whose molecular chain end is blocked with a hydroxyl group or an alkoxysilyl group, and the viscosity at 23 ° C. is 50 to 100,000 mPas,
(B) 3 to 500 parts by weight of an inorganic filler,
(C) 0.1 to 20 parts by weight of a long-chain alkyl group-containing siloxane compound represented by the following general formula, and R ¹ R ² _a Si (OR ³ ) _2-a —O— (SiR ² —O) _n —SiR ² — (CR ⁴ ) _m -SiR ² _b (OR ³ ) _3-b
(In the formula, R ¹ represents a monovalent hydrocarbon having 6 to 40 carbon atoms, R ² represents a monovalent hydrocarbon, R ³ represents an alkyl group, R ⁴ represents a hydrogen atom or an alkyl group, and a represents 0. -2, b is 0-3, m is 2-20, n is an integer of 0-20.)
(D) A room temperature-curable organopolysiloxane composition comprising 0.001 to 10 parts by weight of a curing catalyst.

  Component (A) is a polyorganosiloxane whose molecular chain ends are blocked with a hydroxyl group or an alkoxy group, and is the main component of the room temperature curable composition of the embodiment. If the viscosity of the component (A) is too low, the rubber elasticity after curing will be poor, and if it is too high, the workability will deteriorate, so the viscosity at 23 ° C. is in the range of 50 to 1,000,000 mPas, more preferably in the range of 300 to 100,000 mPas. It is necessary to be in

  The molecular structure of the polyorganosiloxane is preferably a straight chain represented by the following general formula, but may be a structure having a partially branched chain.

In the formula, R ⁵ represents a substituted or unsubstituted monovalent hydrocarbon group which may be the same or different from each other, and R ⁶ represents a monovalent organic group represented by —ZSiR ⁷ _3-p X _p. . Here, Z represents oxygen (oxo group) or a divalent hydrocarbon group, and R ⁷ represents a substituted or unsubstituted monovalent hydrocarbon group which may be the same as or different from each other. X represents a hydroxyl group (hydroxyl group) or an alkoxy group, and p is an integer of 1 to 3. Moreover, q is a number with which the viscosity in 23 degreeC of the said (A) component satisfy | fills 50-1,000,000 mPas.

R ⁵ includes methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group, alkyl group such as dodecyl group; alkenyl group such as vinyl group and allyl group; phenyl group And aryl groups such as tolyl group and xylyl group; aralkyl groups such as 2-phenylethyl group and 2-phenylpropyl group are exemplified, and some of hydrogen atoms of these hydrocarbon groups may be other atoms or groups. Substituted, ie, halogenated alkyl groups such as chloromethyl, 3-chloropropyl, 3,3,3-trifluoropropyl; substituted hydrocarbons such as cyanoalkyl such as 3-cyanopropyl Examples are groups. It is easy to synthesize, and the component (A) has a low viscosity with respect to the molecular weight, gives good extrudability to the composition before curing, and gives good physical properties to the composition after curing. it from is preferably 85% or more of the total R ⁵ is a methyl group, and more preferably substantially all R ⁵ is a methyl group.

On the other hand, in particular, when imparting heat resistance, radiation resistance, cold resistance or transparency to the composition, a necessary amount of phenyl groups as part of R ⁵ , when imparting oil resistance and solvent resistance, When a 3,3,3-trifluoropropyl group or 3-cyanopropyl group is added as a part of R ⁵ or a surface having paintability is applied, a long chain alkyl group or aralkyl is added as a part of R ^5. The group can be arbitrarily selected depending on the purpose, for example, in combination with a methyl group.

The terminal group R ^{6 of the} component (A) is a silicon-functional siloxy unit represented by —ZSiR ⁷ _3-p X _p and having at least one silicon hydroxyl group or alkoxy group X which is a silicon functional group. Therefore, the component (A) of the embodiment has at least one hydroxyl group or alkoxy group X at each end of the molecule.

In the terminal group R ⁶ , R ⁷ bonded to the silicon atom is a substituted or unsubstituted monovalent hydrocarbon group which may be the same as or different from each other and may be the same as or different from R ^5. Materials similar to those in the R ⁵ can be exemplified. A methyl group or a vinyl group is preferable because synthesis is easy and the reactivity of the hydrolyzable group X is excellent. Z is a divalent oxygen (oxo group) or a divalent hydrocarbon group which may be the same or different from each other, and examples of the divalent hydrocarbon group include a methylene group, an ethylene group and a trimethylene group. An alkylene group; a phenylene group and the like. From the viewpoint of easy synthesis, an oxo group or an ethylene group is preferable, and an oxo group is particularly preferable.

X is a silanol group or an alkoxy group which is a silicon functional group present in at least one of R ⁶ which is a terminal group. Examples of alkoxy groups include alkoxyl groups such as methoxy, ethoxy, propoxy, and butoxy; substituted alkoxyl groups such as 2-methoxyethoxy and 2-ethoxyethoxy; enoxy groups such as isopropenoxy And may be the same as or different from each other. Alkoxyl groups such as methoxy, ethoxy and propoxy groups are preferred because of their ease of synthesis, physical properties of the composition prior to curing, stability during storage, curability, economy, and use in a wide range of applications. .

In the terminal group R ⁶ , the number p of hydroxyl groups or alkoxy groups X that are silicon functional groups is preferably 1 to 3. Such a silicon-functional polydiorganosiloxane is obtained by ring-opening polymerization or ring-opening copolymerization of a cyclic diorganosiloxane low monomer such as octamethylcyclosiloxane in the presence of water with an acidic catalyst or an alkaline catalyst, It can be obtained by introducing a hydroxyl group bonded to a silicon atom into the terminal of the obtained linear polydiorganosiloxane.

The silicon-functional polydiorganosiloxane in which X is a hydrolyzable group can be synthesized, for example, by condensing a silane having two or more arbitrary hydrolyzable groups to a polyorganosiloxane having a hydroxyl group at the terminal. it can. In this case, since one hydrolyzable group possessed by the silane is consumed by the condensation reaction, the number of X in the terminal group R ⁶ of the polyorganosilosan obtained by the reaction is the hydrolyzable group-containing silane used. One less than the number of hydrolyzable groups possessed by.

  Specific examples of the polyorganosiloxane as component (A) include dimethylpolysiloxane, methylethylpolysiloxane, methyloctylpolysiloxane, methylvinylpolysiloxane, methylphenylpolysiloxane, methyl (3,3,3-trimethyl). Fluoropropyl) polysiloxane, a copolymer of dimethylsiloxane and methylphenylsiloxane, a copolymer of dimethylsiloxane and methyl (3,3,3-trifluoropropyl) siloxane, and the like. The molecular chain terminal of this polyorganosiloxane is blocked with a hydroxyl group or a hydrolyzable group (for example, alkoxyl group). The molecular chain terminal blocked with a hydroxyl group includes a dimethylhydroxysiloxy group, methylphenylhydroxysiloxy group. Examples of the molecular chain end blocked with an alkoxyl group include a vinyldimethoxysiloxy group, a methyldimethoxysiloxy group, a trimethoxysiloxy group, a methyldiethoxysiloxy group, and a triethoxysiloxy group.

  When the present invention is used in the form of other components such as a main agent and a curing agent, the terminal of the component (A) is generally a silanol group, which is preferable from the reaction rate. In the case of providing in a one-component form, an alkoxysilyl group is preferred at the end of the component (A) from the viewpoints of curability, storage stability, and ease in the production process.

Such polyorganosiloxane has a viscosity at 23 ° C. of 50 to 100,000 mPas, preferably 300 to 100,000 mPas. If the viscosity is less than 50 mPas, it is difficult to impart excellent mechanical properties to the cured product, and if it exceeds 100,000 mPas, the viscosity becomes too high and the workability is practically inferior.
The polyorganosiloxane as the component (A) of the composition of the present invention is a chain polymer in which both ends are blocked with silanol groups. Further, the component (A) may contain a branched polymer.

  (A) The organic group bonded to the silicon atom in the diorganosiloxane that is the structural unit of the component may be the same or different, for example, methyl group, ethyl group, propyl group, butyl group, hexyl group, dodecyl group, etc. Alkyl groups such as vinyl and allyl groups; aryl groups such as phenyl and tolyl groups; aralkyl groups such as benzyl, β-phenylethyl, and β-phenylpropyl; and 3,3,3- Examples thereof include monovalent substituted hydrocarbon groups such as a trifluoropropyl group and a chloromethyl group. Among these, a methyl group, a vinyl group, or a phenyl group is preferable from the viewpoint of ease of synthesis. Furthermore, when the organic group bonded to the silicon atom is a methyl group, the raw material is compared with the case of other organic groups. The intermediate is easy to synthesize, the viscosity is the lowest compared to the degree of polymerization of the resulting polymer, and the balance of physical properties of the rubber-like elastic body, which is a cured product, is most preferred. For this reason, it is most preferable that substantially all are methyl groups, but when the cured product requires heat resistance, it is preferable that some of the organic groups bonded to the silicon atom are phenyl groups. . Even when organic groups other than methyl groups are contained in this way, it is preferable that 85% or more of the total number of organic groups in the polymer is methyl groups for the reasons described above.

As the component (B), an inorganic filler is blended in view of reinforcing properties. In general, conventionally known fillers can be widely used as inorganic fillers, and specifically, reinforcing fillers such as fumed silica, precipitated silica, anhydrous silicic acid, hydrous silicic acid, and carbon black. Fibrous fillers such as wood, calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, organic bentonite, ferric oxide, zinc oxide, activated zinc white, asbestos, glass fiber and filaments Etc. can be illustrated. Among these, in view of the thixotropy, viscosity, and adhesive properties of the resulting composition, calcium carbonate is preferable, and the addition of colloidal calcium carbonate is more preferable. Furthermore, it is preferable to add colloidal calcium carbonate having a BET specific surface area of 14.0 to 20.0 m ² / g, an average particle size of 0.05 to 0.20 μm, and a particle surface treated. If the average particle size is less than 0.05 μm, the viscosity becomes too high and the workability is practically inferior, and if it exceeds 0.20 μm, excellent mechanical properties cannot be imparted to the cured product. Can not be imparted to excellent mechanical properties in the cured product is less than even 14.0 m ² / g for the BET specific surface area, poor practical workability becomes too high viscosity exceeds 20.0 m ² / g. Furthermore, examples of the surface treatment of calcium carbonate include those treated with a resin acid containing fatty acids and fatty acid salts, fatty acid esters, rosin acid and the like and salts thereof. Those treated with rosin acid or a metal salt thereof are preferred in that they give the hardened rubber with the highest modulus and are excellent in resistance to heat and humidity and water resistance.

  Examples of such calcium carbonate include Homocal D, Homocal DM, Shiroka Hana TDD, Shiraka Hana IGV (trade name, manufactured by Shiroishi Kogyo Co., Ltd.) and MT-100M (trade name, manufactured by Maruo Calcium Co., Ltd.).

The amount of component (B) is 3 to 500 parts by weight, preferably 5 to 200 parts by weight, per 100 parts by weight of component (A). If the amount is less than 3 parts by weight, excellent mechanical properties cannot be imparted to the cured product. If the amount exceeds 500 parts by weight, the viscosity becomes too high and the workability is practically inferior. Further, heavy calcium carbonate may be blended as long as the mechanical properties and the water resistance are not impaired. The blending of heavy calcium carbonate is effective in improving workability such as viscosity adjustment, and it is preferable that the surface of such heavy calcium carbonate be treated in the same manner as the calcium carbonate carbonate.
The component (C) is a long-chain alkyl group-containing siloxane compound represented by the following general formula.

R ¹ R ² _a Si (OR ³ ) _2-a —O— (SiR ² —O) _n —SiR ² — (CR ⁴ ) _m —SiR ² _b (OR ³ ) _3-b
(In the formula, R ¹ represents a monovalent hydrocarbon having 6 to 40 carbon atoms, R ² represents a monovalent hydrocarbon, R ³ represents an alkyl group, R ⁴ represents a hydrogen atom or an alkyl group, and a represents 0. -2, b is 0-3, m is 2-20, n is an integer of 0-20.)
In the above general formula, R ¹ is a monovalent hydrocarbon group having preferably 6 to 40, more preferably 8 to 40, and still more preferably 12 to 40 unsubstituted or substituted carbon atoms. When R ¹ is a monovalent hydrocarbon group, if the number of carbon atoms of R ¹ is within this range, the resulting organosilicon compound has a sufficient effect of improving immersion resistance, and low temperature (for example, -40 ~ -20 ℃), it is hard to solidify and easy to handle. When R ¹ is a monovalent hydrocarbon group, specific examples thereof include hexyl group, heptyl group, octyl group, nonyl group, octyl group, nonyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group Alkyl groups such as eicosyl group; cycloalkyl groups such as cyclohexyl group; alkenyl groups such as hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, dodecenyl group, tetradecenyl group; phenyl group, tolyl group, xylyl group, Aryl groups such as naphthyl group; aralkyl groups such as benzyl group, 2-phenylethyl group and 2-methyl-2-phenylethyl group; or a part or all of hydrogen atoms bonded to carbon atoms of these hydrocarbon groups Groups substituted with halogen atoms such as fluorine, bromine and chlorine, such as 2- (nonafluorobutyl) ethyl group, 2- ( Descriptor tridecafluorooctyl) ethyl group, a p- chlorophenyl group.

R ² is the same or different unsubstituted or substituted monovalent hydrocarbon group having preferably 1 to 8, more preferably 1 to 5 and even more preferably 1 to 3 carbon atoms. Specific examples of R ² include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, t-butyl group, pentyl group, hexyl group and octyl group; cycloalkyl such as cyclopentyl group and cyclohexyl group. An alkenyl group such as a vinyl group, an allyl group, or a butenyl group; an aryl group such as a phenyl group, a tolyl group, or a xylyl group; or a part or all of hydrogen atoms bonded to carbon atoms of these hydrocarbon groups, Groups substituted with halogen atoms such as bromine and chlorine, such as chloromethyl group, bromoethyl group, 3,3,3-trifluoropropyl group, 2- (nonafluorobutyl) ethyl group, p-chlorophenyl group, etc. Of these, a methyl group and an ethyl group are particularly preferred from the viewpoint of ease of synthesis and economical efficiency of the organosilicon compound of the present invention.

R ³ is the same or different unsubstituted or substituted monovalent organic group having preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3 carbon atoms. More specifically, R ³ is, for example, independently, an unsubstituted or substituted monovalent hydrocarbon having preferably 1 to 6, more preferably 1 to 4, even more preferably 1 to 3 carbon atoms. Group, alkoxyalkyl group, acyl group and the like. When R ³ is a monovalent hydrocarbon group, specific examples thereof include an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a t-butyl group, a pentyl group, and a hexyl group; a cyclopentyl group Cycloalkyl group such as cyclohexyl group; alkenyl group such as vinyl group, allyl group, butenyl group; phenyl group; or part or all of hydrogen atoms bonded to carbon atoms of these monovalent hydrocarbon groups may be fluorine, bromine , Groups substituted with halogen atoms such as chlorine, for example, chloromethyl group, bromoethyl group, 3,3,3-trifluoropropyl group, 2- (nonafluorobutyl) ethyl group, p-chlorophenyl group, etc. . When R ³ is an alkoxyalkyl group, examples thereof include an alkoxyalkyl group such as a methoxyethyl group, a methoxypropyl group, an ethoxyethyl group, a butoxyethyl group; or a bond to a carbon atom of these alkoxyalkyl groups. And a group obtained by substituting a part or all of the hydrogen atoms with a halogen atom such as fluorine, bromine or chlorine. Further, when R ³ is an acyl group, examples thereof include acyl groups such as acetyl group, propionyl group, acryloyl group, methacryloyl group; or part or all of hydrogen atoms bonded to carbon atoms of these acyl groups Are substituted with a halogen atom such as fluorine, bromine or chlorine. Among these, a methyl group and an ethyl group are particularly preferable from the viewpoint of ease of synthesis and economical efficiency of the organosilicon compound of the present invention.

  m is usually an integer of 0 to 4, preferably 0 to 3, more preferably 0 to 2, and still more preferably 0 from the viewpoint of ease of synthesis of the organosilicon compound of the present invention and economical efficiency. It is an integer of ~ 1. In the above general formula, n is usually an integer of 2 to 20, and is preferably 2 from the viewpoint of ease of synthesis and economical efficiency of the organosilicon compound used in the present invention.

  Specific examples of the organosilicon compound represented by the general formula of component (C) include, but are not limited to, the following compounds.

  These may be used alone or in combination of two or more.

The organosilicon compounds represented by these general formulas are synthesized as follows.
An organohydrogensiloxane and an alkenylsilane such as vinylalkoxysilane are reacted in the presence of a hydrosilylation catalyst to synthesize a one-end organohydrogensiloxane once. This reaction may be performed in the absence of a solvent or in the presence of a solvent such as toluene. The reaction temperature is usually 70 to 100 ° C, preferably 70 to 90 ° C. The reaction time may be 1 to 3 hours. In this reaction, the amount of alkenylsilane added is preferably 0.5 to 1.0 mol, more preferably 0.5 to 0.6 mol, with respect to 1 mol of the organohydrogensiloxane.

  Subsequently, the organosilicon compound is obtained by reacting the obtained one-end organohydrogensiloxane and alkene in the presence of a hydrosilylation catalyst. Examples of the alkene include 1-nonene, 1-tridecene, 1-undecene, 1-hexadecene, 1-octadecene, alpha olefin, dialen 16, dialen 18, dialen 168, and dialen 208 manufactured by Mitsubishi Chemical Corporation.

  The reaction temperature is 70 to 100 ° C., preferably 70 to 90 ° C., as before. The reaction time may be 1 to 3 hours. In this reaction, the amount of alkene added is preferably 1.0 to 1.5 mol, more preferably 1.0 to 1.2 mol, with respect to 1 mol of one-end organohydrogensiloxane.

  The hydrosilylation catalyst used in the above synthesis comprises an aliphatic unsaturated group (alkenyl group, diene group, etc.) in one raw material compound and a silicon atom-bonded hydrogen atom (that is, SiH group) in the other raw material compound. A catalyst for addition reaction. Examples of the hydrosilylation catalyst include platinum group metal catalysts such as platinum group metals alone and their compounds. As the platinum group metal-based catalyst, conventionally known ones can be used. Specific examples thereof include finely divided platinum metal adsorbed on a support such as silica, alumina or silica gel, platinous chloride, chloroplatinic acid, chlorination. An alcohol solution of platinum acid hexahydrate, a palladium catalyst, a rhodium catalyst, and the like can be given, and those containing platinum as the platinum group metal are preferable. A hydrosilylation catalyst may be used individually by 1 type, or may be used in combination of 2 or more type. The addition amount of the hydrosilylation catalyst may be an effective amount that can promote the above addition reaction, and is usually 1 ppm (mass basis, hereinafter the same) to 1 mass in terms of the total amount of raw material compounds in terms of the amount of platinum group metal. %, Preferably 10 to 500 ppm. If the addition amount is within this range, the addition reaction is likely to be sufficiently promoted, and the addition reaction rate is likely to increase with an increase in the addition amount, which is economically advantageous.

  The amount of component (C) is 0.1 to 20 parts by weight per 100 parts by weight of component (A). When the amount is less than 0.1 part by weight, the crosslinking reaction is not sufficiently performed, and when the amount exceeds 20 parts by weight, an excessive crosslinking component that is not consumed by the crosslinking reaction adversely affects the properties of the rubber-like elastic body.

  The component (D) curing catalyst serves as a catalyst for accelerating the curing of the composition of the present invention, and includes tin, titanium, zirconium, iron, antimony, bismuth or manganese organic carboxylates, organic titanates, and organic titanium chelates. Compound etc. are mentioned. Specific examples of the catalyst used include tin compounds such as dibutyltin dilaurate, dibutyltin dioctoate, dioctyltin dilaurate, dibutyltin malate ester, stannous octoate; tetrabutyl titanate, diisopropoxybis (acetylacetonate) Titanium compounds such as titanium and diisopropoxybis (ethyl acetoacetate) can be mentioned. Component (D) is added in an amount of 0.001 to 10 parts by weight, preferably 0.01 to 5 parts by weight per 100 parts by weight of component (A). This is because if the amount of the component (D) is too small, the curing rate is too slow to be suitable for practical use.

Furthermore, in the present invention, as the component (E), a mixture or reaction mixture of aminoalkylalkoxysilane and epoxyalkylalkoxysilane acts as a crosslinking agent for the composition of the present invention, and is used for various substrates that are in contact during curing. It functions to impart adhesiveness, and when used in combination with component (C), imparts adhesive durability under severe conditions such as warm water immersion to the cured product of the composition of the present invention. Examples of the aminoalkylalkoxysilane constituting the component (E) include aminomethyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, N- (aminoethyl) aminomethyltributoxysilane. N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, and γ-anilinopropyltriethoxysilane. Epoxyalkylorganoalkoxysilanes include γ-glycidoxyprolyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β- (4,3-epoxycyclohexyl) ethyltrimethoxysilane, β- (3 , 4-Epoxycyclohexyl) ethylmethyldimethoxysilane. These aminoalkylalkoxysilanes and epoxyalkylalkoxysilanes are mixed in a molar ratio of (1: 1.5) to (1: 5), preferably (1: 2) to (1: 4), and stored at room temperature or heated. By doing so, a reaction mixture can be easily obtained. Component (E) is added in an amount of 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight per 100 parts by weight of component (A). This is because if the amount of the component (E) is too small, sufficient rubber strength and adhesiveness cannot be obtained, and if it is too large, the curing rate becomes slow, or the cured rubber becomes too hard.
In the composition of the present invention, an alkoxysilane different from the component (C) and the component (E) can be further added as a crosslinking agent in order to adjust the curability and the rubber strength after curing. Examples of such alkoxysilane include tetrafunctional alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, methyl cellosolve orthosilicate, and n-propyl orthosilicate; methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, vinyl Examples thereof include trifunctional alkoxysilanes such as trimethoxysilane, phenyltrimethoxysilane, and methyltrimethoxyethoxysilane, and partial hydrolysates thereof.

  Furthermore, the composition of the present invention contains an organic solvent, a terminal trimethylsiloxylated diorganopolysiloxane, a flame retardant, a plasticizer, a thixotropic agent, a colorant, a normal adhesion promoter, an antifungal agent, and the like as necessary. Addition may be made as long as the object of the present invention is not impaired.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the examples and comparative examples, “parts” all represent parts by weight.

  In the examples, the following long-chain alkyl group-containing siloxane compounds were used as the component (C).

Example 1
Collagen calcium carbonate `` Shiraka Hana TDD '' surface-treated with rosin acid with a BET specific surface area of 16.0 m ² / g and an average particle size of 0.06 μm on 100 parts of polydimethylsiloxane with a viscosity of 5,000 mPas blocked at both ends of the molecular chain with silanol groups 100 parts (product name, manufactured by Shiroishi Kogyo Co., Ltd.) were mixed until uniform (hereinafter, the obtained mixture is referred to as a base). On the other hand, carbon black (VULCAN XC72, manufactured by CABOT) is uniformly dispersed in α, ω-divinylmethylsiloxane having a viscosity of 1,000 mPas, and then the components shown in Table 1 are mixed and defoamed to obtain a catalyst composition. 1 was obtained. Next, the base and catalyst composition were mixed and defoamed at a ratio of 100: 10 (weight ratio) to obtain the composition of the present invention.
Examples 2-10, Comparative Examples 1-6
A composition was obtained and evaluated in the same manner as in Example 1 except that the type and amount of each component to be blended were changed as shown in Tables 1 and 2. The results are shown in Table 1. "Micropowder 2R" (Bihoku Flour Chemical Co., Ltd., trade name) as heavy calcium carbonate used in combination with the colloidal calcium carbonate "Shirakaka TDD" (Shiraishi Kogyo Co., Ltd., trade name) blended in the base Also, heavy calcium carbonate powder [trade name ESD-18] manufactured by Sankyo Flour Milling Co., Ltd. was used.
Example 11
Collagen calcium carbonate with a BET specific surface area of 17.0 m ² / g and an average particle size of 0.07 μm and treated with stearic acid with a viscosity of 5,000 mPas and sealed with silanol groups at both ends of the molecular chain. 100 parts of S ”(trade name, manufactured by Shiroishi Kogyo Co., Ltd.) were mixed until uniform (hereinafter, the obtained mixture is referred to as a base). On the other hand, each component shown in Table 1 was mixed and defoamed to obtain a catalyst composition. Subsequently, the base and the catalyst composition were mixed and defoamed at a ratio of 100: 10 (weight ratio) to obtain the composition 11 of the present invention.
Examples 12-14, Comparative Examples 7-10
A composition was obtained and evaluated in the same manner as in Example 1 except that the type and amount of each component to be blended were changed as shown in Table 2. The results are shown in Table 1. "Micropowder 2R" (Bihoku Flour Chemical Co., Ltd., trade name) as heavy calcium carbonate used in combination with the colloidal calcium carbonate "Shirakaka TDD" (Shiraishi Kogyo Co., Ltd., trade name) blended in the base Also, heavy calcium carbonate powder [trade name ESD-18] manufactured by Sankyo Flour Milling Co., Ltd. was used.

The hardness of this composition after 4 hours, 8 hours and 24 hours was examined. Further, the adhesion durability was evaluated by the following method.
<Method for evaluating adhesion durability of room temperature-curable organopolysiloxane composition>
An adhesion durability test specimen was prepared in accordance with the method specified in JIS K5758 architectural sealant. That is, a room temperature curable organopolysiloxane composition was filled between two float glass plates (float plate glass defined in JIS R3202) to prepare an adhesion durability test specimen (commonly known as an H-shaped test specimen). . This adhesion durability test specimen was allowed to stand for 7 days under conditions of a temperature of 23 ° C. and a humidity of 50% to cure the composition. The tensile adhesion strength of the obtained adhesion durability test specimen was measured, and the breaking state of the silicone rubber was observed together. Further, this adhesion durability test specimen was immersed in warm water at 80 ° C. for 7 days, then taken out, measured for tensile adhesive strength, and observed for the breaking state of the silicone rubber. These measurement results and observation results were expressed as follows.
M50: 50% tensile stress Tmax: Maximum tensile stress Emax: Elongation at maximum load
CF: cohesive failure (destructed with silicone rubber layer)
TCF: Thin layer breakage (broken by leaving a thin layer of silicone rubber at the interface with the glass plate)
AF: Adhesion failure (peeling at the interface between glass plate and silicone rubber)
Examples 15-17
Collagen calcium carbonate `` Shiraka Hana '' surface-treated with rosin acid with a BET specific surface area of 16.0 m ² / g and an average particle size of 0.06 μm on 100 parts of polydimethylsiloxane with a viscosity of 10,000 mPas blocked at both ends of the molecular chain with trimethoxysiloxy groups 75 parts of TDD (manufactured by Shiraishi Kogyo Co., Ltd., trade name) and 75 parts of heavy calcium carbonate “Micro Powder 2R” (trade name, manufactured by Bihoku Flour Chemical Co., Ltd.) were mixed until uniform. Next, 30 parts of polydimethylsiloxane having a viscosity of 100 mPas and having both ends of the molecular chain blocked with trimethylsiloxy groups were mixed until uniform. Further, 3 parts of a long chain alkyl group-containing siloxane A, 1 part of methyltrimethoxysilane, 0.8 part of a reaction mixture of 3-aminopropyltrimethoxysilane and 3-glycidoxysilyltrimethoxysilane, 1,3,5-tris [3 0.5 parts of-(trimethoxysilyl) propyl] cyclotriisocyanurate and 3 parts of diisopropoxybis (ethylacetylacetate) titanium were blended and subjected to defoaming and mixing until uniform, whereby composition 15 was obtained. In the same manner, composition 16 was obtained using long-chain alkyl group-containing siloxane B instead of long-chain alkyl group-containing siloxane A, and composition 17 was obtained using long-chain alkyl group-containing siloxane D.
Comparative Examples 11-14
Comparative compositions 11 to 14 were obtained in the same manner as in Example 15 using the curing agent components shown in Table 3.
Example 18
Surface treatment with stearic acid having a BET specific surface area of 17.0 m ² / g and an average particle size of 0.07 μm in place of the colloidal calcium carbonate “Shirakaka TDD” (trade name, manufactured by Shiroishi Kogyo Co., Ltd.) in the same manner as in Example 15. The composition 18 was obtained using the colloidal calcium carbonate “Hakuenka CCR-S” (trade name, manufactured by Shiroishi Kogyo Co., Ltd.).

The following evaluation was performed about the obtained compositions 15-18 and the comparative compositions 11-14.
(A) Dischargeability: The tip of the cartridge nozzle was set to 6.2 mm in inner diameter, the plunger was pushed using an autograph, and the force for pushing out the composition was measured.
(B) Drying time to touch: The composition was extruded into an atmosphere of 23 ° C. and 50% RH, and the time taken to contact the surface with the finger and confirm that it was dry was measured.
(C) Physical properties: Extrude the composition into a sheet with a thickness of 2 mm, leave it at 23 ° C and 50% RH for 168 hours, cure it with moisture in the air, and measure its physical properties according to JIS K 6301 did.
(D) Storage stability: The composition was put in a container where moisture was cut off, heated at 70 ° C. for 5 days, and then the touch drying time was measured in an atmosphere of 23 ° C. and 50% RH. Further, it was extruded into a sheet having a thickness of 2 mm, allowed to stand at 23 ° C. and 50% RH for 168 hours, cured by moisture in the air, and its physical properties were measured according to JIS K 6301.
(E) Physical properties: Measured according to the measurement method specified in JIS A 5758 architectural sealant. As the adherend, an alumite sulfate sealed aluminum test panel (manufactured by Engineering Test Piece Service Co., Ltd.) defined in JIS H 4000 (A5052P) was used.

Claims (3)

(A) 100 parts by weight of a polyorganosiloxane whose molecular chain end is blocked with a hydroxyl group or an alkoxysilyl group, and the viscosity at 23 ° C. is 50 to 100,000 mPas,
(B) 3 to 500 parts by weight of an inorganic filler,
(C) 0.1 to 20 parts by weight of a long-chain alkyl group-containing siloxane compound represented by the following general formula, and R ¹ R ² _a Si (OR ³ ) _2-a —O— (SiR ² —O) _n —SiR ² — (CR ⁴ ) _m -SiR ² _b (OR ³ ) _3-b
(In the formula, R ¹ represents a monovalent hydrocarbon having 6 to 40 carbon atoms, R ² represents a monovalent hydrocarbon, R ³ represents an alkyl group, R ⁴ represents a hydrogen atom or an alkyl group, and a represents 0. -2, b is 0-3, m is 2-20, n is an integer of 0-20.)
(D) curing catalyst 0.001 to 10 parts by weight ,
(E) A room temperature-curable organopolysiloxane composition comprising 0.1 to 20 parts by weight of a mixture or reaction mixture of aminoalkylalkoxysilane and epoxysilane . ^2. The room temperature curable organopolysiloxane composition according to claim 1, wherein the inorganic filler is a surface-treated colloidal calcium carbonate having a BET specific surface area of 14.0 to 20.0 m ² / g and an average particle size of 0.05 to 0.20 μm.   The room temperature-curable organopolysiloxane composition according to claim 2, wherein the surface treatment agent for colloidal calcium carbonate is rosin acid or a metal salt of rosin acid.