JP3413712B2 - Room temperature curable organopolysiloxane composition for working joint - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a room temperature curable organopolysiloxane composition which is easily cured by moisture in the air to form a rubber elastic body and which is particularly excellent in stress relaxation and is used for a working joint.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
Room temperature-curable organopolysiloxane compositions that are easily cured by moisture to form rubber elastic bodies are widely used for applications such as adhesives, coating materials, electrical insulating sealing materials, and sealing materials for construction. In this case, for such applications, a one-component organopolysiloxane composition usually containing an organopolysiloxane having both ends blocked with hydroxyl groups and an organosilicon compound having at least three hydrolyzable groups in one molecule. In this type of one-component organopolysiloxane composition, a curing agent is separately packaged and compared with a two-component organopolysiloxane composition which is added to both end hydroxyl group-blocked organopolysiloxane at the time of use, It has a large modulus and a small elongation, and no one has passed the durability test 10030 grade of JIS A-5758 without a primer.

That is, the conventional one-component sealing material is JIS
Several organopolysiloxane compositions that pass the A5758 durability test 10030 grade have been proposed. However, since the composition is basically the same as that of the two-component type sealing material, the workability is remarkably reduced.

Generally, even a sealing material having good adhesiveness does not have sufficient adhesiveness at a working joint portion which is a joint portion of a large movement.

Therefore, the present invention is based on JIS A-5758.
It is an object of the present invention to provide a room temperature curable organopolysiloxane composition for a working joint, which is compatible with a durability test of 10030 grade and has excellent adhesiveness in a large joint portion of a movement.

[0006]

Means for Solving the Problems and Modes for Carrying Out the Invention As a result of intensive studies to achieve the above-mentioned object, the present inventor has found that (A) both-end hydroxyl group-blocked diorganopolysiloxane and (B) one molecule At least 3 hydrolyzable groups in
A room temperature-curable organopolysiloxane composition containing an organic silicon compound as a main component, and having (C) a carbon number having at least one structure selected from an aliphatic unsaturated bond, a branched structure, and an ether bond in the molecule. Calcium carbonate treated with one or two or more treating agents selected from 8 or more carboxylic acids, and by adding calcium carbonate having a treatment amount of 1 to 2.5% by weight, even without a primer It provides excellent adhesion to various substrates such as glass, aluminum, fluororesin, acrylic resin, etc., and also provides a cured product that excels in stress relaxation and passes JIS A-5758 durability grade 10030. To obtain a one-component room-temperature-curing organopolysiloxane composition effective for use in parts, and It has been found that it has excellent adhesiveness even when subjected to movement, and also has excellent heat resistance / water-immersive adhesiveness. Further, in addition to the components (A), (B), and (C) above,
(D) Calcium carbonate treated with a carboxylic acid having no aliphatic unsaturated bond, branched structure, or ether bond in the molecule and having a melting point of 100 ° C. or higher, the treatment amount being 1 to 2 The present invention has been made based on the finding that the addition of calcium carbonate in an amount of 0.5% by weight can impart more excellent properties such as adhesiveness.

Conventionally, room temperature-curable organopolysiloxane compounds using calcium carbonate as a filler are disclosed in Japanese Patent Application Laid-Open No. 5-39422 and US Pat. No. 5,405.
Although there are proposals in Japanese Patent No. 889, these are all proposals for a room temperature-curable organopolysiloxane composition of a two-component type, and up to now, a one-component type of JIS A-57.
No compositions have been proposed that pass 58 10030 durability grades without a primer.

The present invention will be described in more detail below.

The component (A) which is the base polymer of the room temperature curable organopolysiloxane composition of the present invention is a diorganopolysiloxane represented by the following general formula (1).

[0010]

[Chemical 3] (In the formula, R ¹ is the same or different from each other, unsubstituted or substituted 1
It is a valent hydrocarbon group, and n is an integer of 2 or more. )

Here, in the above general formula (1), the monovalent hydrocarbon group R ¹ is preferably one having 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, an alkyl group such as a hexyl group, a phenyl group, an aryl group such as a tolyl group, a vinyl group, an allyl group, an alkenyl group such as a butenyl group, a benzyl group, Aralkyl groups such as 2-phenylethyl group and groups in which some or all of hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms, cyano groups, etc., for example, chloromethyl group, trifluoropropyl group, cyanoethyl group And so on. Of these, a methyl group, a phenyl group, a vinyl group and a trifluoropropyl group are preferable, and a methyl group is particularly preferable.

In the general formula (1), n is a number corresponding to the degree of polymerization, and is 2 in terms of viscosity and workability.
It is an integer above, and particularly preferably an integer in the range of 50 to 2000.

Specific examples of the diorganopolysiloxane as the component (A) include those represented by the following chemical formula.

[0014]

[Chemical 4] (In the above formula, Me is a methyl group, Ph is a phenyl group, p and q are positive integers, and p + q is an integer corresponding to n.)

Next, the component (B) of the composition of the present invention is an organosilicon compound having at least 3 hydrolyzable groups in the molecule. This acts as a curing agent and is an essential component for the composition of the present invention to cure at room temperature in the presence of moisture.

In this organosilicon compound, examples of the hydrolyzable group include alkoxy groups such as methoxy group, ethoxy group, propoxy group, butoxy group and methoxyethoxy group, propenooxy group, isobutenyloxy group, 1-
Alkenyloxy group such as ethyl-2-methylvinyloxy group, dimethylketoxime group, methylethylketoxime group, diethylketoxime group, ketoxime group such as cyclopentanooxime group, acetoxy group, propionoxy group, butyroyloxy group, benzoyl group, etc. Acyloxy group, N-methylamino group, N-ethylamino group, N-propylamino group, N-butylamino group, N,
Amino group such as N-dimethylamino group, N, N-diethylamino group, cyclohexylamino group, amide group such as N-methylacetamide group, N-methylbenzamide group, N, N-dimethylaminoxy group, N, N- Aminoxy groups such as diethylaminoxy group, isocyanate groups,
Examples thereof include α-silyl ester groups and halogen atoms such as chlorine atoms. However, if a halogen atom such as a chlorine atom is used as the hydrolyzable group, it is dangerous to generate a highly corrosive and toxic hydrogen halide during the hydrolysis reaction. Should be.

The group other than the hydrolyzable group capable of binding to the silicon atom of the organosilicon compound is preferably a substituted or unsubstituted monovalent hydrocarbon group similar to R ^{1 in the} component (A). From the viewpoint of easy synthesis, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, a phenyl group and the like are preferable.

Specific examples of the organosilicon compound as the component (B) include, for example, methyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane. Alkoxysilanes such as 3-chloropropyltrimethoxysilane,
Enoxysilanes such as methyltriisopropenoxysilane, vinyltriisopropenoxysilane, phenyltriisopropenoxysilane, methyltris (methylethylketoxime) silane, vinyltris (methylethylketoxime) silane, phenyltris (methylethylketoxime) silane, methyltris (dimethylketo) Oxime) silane, ketoxime silane such as tetrakis (methylethylketoxime) silane, methyltriacetoxysilane, vinyltriacetoxysilane, aminosilane such as phenyltris (N, N-diethylamino) silane, methyltris (N-methylacetamide) silane, vinyltris Aminooxysilanes such as (N-aminoxy) silane and vinyltris (N, N-diethylaminoxy) silane, and the like. Partially hydrolyzed et organosilicon compounds and the like.

The amount of the component (B) used is the same as that of the component (A).
The amount is preferably 0.2 to 30 parts by weight, and more preferably 0.5 to 100 parts by weight of the component diorganopolysiloxane.
~ 20 parts by weight. If the amount used is too small, curing of the composition will be insufficient, and if it is too large, the resulting cured product will be hard and brittle, and the performance as a sealing material may be impaired.

The component (C) of the composition of the present invention is surface-treated calcium carbonate. In this case, as the surface treatment agent,
One or more kinds selected from carboxylic acids having 8 or more carbon atoms and having at least one kind of structure selected from aliphatic unsaturated bond, branched structure and ether bond in the molecule are used. These preferably have a melting point of less than 100 ° C.

Typical treating agents include oleic acid and N.
-Oleyl sarcosine, isostearic acid, isooleic acid, isopalmitic acid, phenoxyacetic acid, 11-phenoxybenzoic acid, sorbic acid, triphenylacetic acid, undecylenic acid, (2-naphthoxy) acetic acid, 2-norbornaneacetic acid, o, m, p -Methoxycinnamic acid, 2-methoxyphenylacetic acid, α-methylcinnamic acid, 3-methylvaleric acid, trans-muconic acid, 1-naphthylacetic acid, lactobionic acid, levulinic acid, linoleic acid, lithocholic acid, lysine, isoleucine, Indole-3-pyruvate, 1
-Indoline-2-carboxylic acid, 3-indole butyric acid,
Indole-3-acetic acid, indole-2-carboxylic acid,
Imidazole-4-acrylic acid, 4-hydroquinoline-
2-carboxylic acid, L-hydroxyproline, 3- (4-
Hydroxyphenyl) propionic acid, 4-hydroxyphenylglycine, 12-hydroxyoctadecanoic acid, 3
-(4-hydroxyphenyl) propionic acid, 18-glycyrrhetinic acid, glycyrrhetinic acid, glycyrrhizinic acid, erucic acid, 2-ethylhexanoic acid, dehydrocholic acid, deoxycholic acid, cis-9-octadecenoic acid dibutylammonium, trans-2 , 4-dichlorocinnamic acid, 2,4-dichlorophenoxyacetic acid, 3,4-dihydroxycinnamic acid, 3,3-dimethylglutaric acid, docosenoic acid, cyclohexylphenylacetic acid, and the like. However, the above condition may be satisfied. Furthermore, as the condition of the treating agent, it is preferable that the acidity is not strong. This is because if the acidity is strong, the calcium carbonate may react and foam when the surface treatment is performed. Among these, oleic acid, isostearic acid, erucic acid, linoleic acid and the like are preferable in terms of cost and availability.

The amount of surface-treated calcium carbonate treated with the above treatment agent is in the range of 1 to 2.5% by weight. 1
If less than wt%, sufficient adhesion cannot be obtained, and 2.5 wt%
When it exceeds, the treating agent is released and acts as a release agent, which adversely affects the adhesiveness.

The treating agent used in the component (C) and another treating agent may be treated together with calcium carbonate.
It is necessary that the amount of treatment in the surface-treated calcium carbonate with the treatment agent used as the component (C) is 1 to 2.5% by weight.

The average particle size of calcium carbonate is preferably 0.01 to 0.2 μm from the viewpoint of adhesiveness.

The amount of the component (C) blended is 10 to 200 parts by weight, particularly 30 parts by weight, per 100 parts by weight of the component (A).
It is preferably in the range of 100 to 100 parts by weight. If the amount of component (C) is too small, it becomes easy to flow, resulting in poor workability.
On the other hand, if the amount of the component (C) is large, the component becomes hard and the workability may deteriorate.

In addition to the surface-treated calcium carbonate of the component (C), the composition of the present invention has, as the component (D), any structure of an aliphatic unsaturated bond, a branched structure and an ether bond. It is possible to incorporate calcium carbonate which has been surface treated with a non-carboxylic acid. As a result, it exhibits adhesiveness even without a primer, and also has excellent heat resistance and water immersion adhesiveness, and also shows good adhesiveness to fluororesin coated steel sheets and acrylic electrodeposition coated steel sheets, and passes JIS A-5758 durability grade 10030. Can be obtained.

Here, as the carboxylic acid having no structure of the component (C) and having a melting point of 100 ° C. or higher, abietic acid,
Examples include dehydroabietic acid and saturated fatty acids having a melting point of 100 ° C. or higher represented by C _m H _{2m + 1} COOH (m is a positive integer), and rosin acid is preferable in terms of availability and cost. Used. In addition, calcium carbonate is
These can be treated alone or in combination of two or more. When treating calcium carbonate with a treating agent having a melting point of 100 ° C. or higher, the treatment amount is 1 to
The amount is preferably 2.5% by weight, and outside this range, the treatment effect may not be sufficiently exhibited. Further, as the calcium carbonate, one having an average particle diameter of 0.01 to 0.2 μm is preferable for the same reason as described above.

When the component (D) is used in addition to the component (C), the total amount of the components (C) and (D) is (A) component 1
10 to 200 parts by weight, especially 30 to 1 to 100 parts by weight
It is preferably 00 parts by weight. In this case, the weight ratio of the calcium carbonate as the component (C) and the calcium carbonate as the component (D) is preferably in the range of (C) :( D) = 10: 90 to 90:10. When the amount of the component (C) is large, the water-adhesiveness is poor, and when the amount of the component (D) is large, the modulus tends to be large. More preferably (C) :( D) = 3
The range is 0:70 to 70:30.

The surface treatment of the carboxylic acid of the calcium carbonate can be carried out by a conventional method of surface treatment. In this case, calcium carbonate can be simultaneously treated with the treating agent of component (C) and the treating agent of component (D). Of course, calcium carbonate treated separately with the treating agent of the component (C) and the treating agent of the component (D) can be used together.

A condensation catalyst may be used in the room temperature-curable organopolysiloxane composition of the present invention to accelerate the curing of the composition. For example, it is conventionally used as a curing accelerator in compositions of this type. Condensation catalyst used in, for example, dibutyltin dimethoxide, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dimethyltin dimethoxide, organic tin compounds such as dimethyltin diacetate, tetrapropyl titanate, tetrabutyl titanate, Tetra
A metal Lewis acid such as an organic titanium compound such as 2-ethylhexyl titanate or dimethoxytitanium diacetylacetonate; an amine compound such as 3-aminopropyltrimethoxysilane or tetramethylgranidylpyrtrimethoxysilane; Combinations of more than one species can be used.

In general, the amount of the condensation catalyst used is preferably 10 parts by weight or less, more preferably 0 to 5 parts by weight, per 100 parts by weight of the component (A). If the amount of the condensation catalyst used is too large, cracking or damage after the durability test is likely to occur, which is not preferable.

In addition to the above condensation catalyst, the composition of the present invention may optionally contain various compounding agents such as fillers, pigments, silica, dyes, adhesion promoters, thixotropy improvers and rust preventives. , Flame retardants, antifungal agents, etc. may be added.

The composition of the present invention can be prepared as a one-component form by mixing the above components.

The composition of the present invention also adheres well to various substrates such as glass, aluminum, fluororesin coated steel sheets, acrylic resin electrodeposition coated steel sheets, etc., and as a result, it has a large movement between metal joints and around glass. It is effective for use as a sealing material for working joints such as joints, joints of cement-based boards, joints of porous members and the like.

[0035]

INDUSTRIAL APPLICABILITY The room temperature curable organopolysiloxane composition for a working joint of the present invention is excellent in stress relaxation and can be used in accordance with JIS A-5758 100 without a primer.
It gives a cured product that passes the 30 durability grade.

[0036]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following examples, the viscosity shows the value at 25 ° C. Moreover,% shows weight%.

[Example 1] α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% oleic acid treated calcium carbonate (particle size 0.10μ
m) 50 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.
An H-type test body was obtained using a sample obtained by charging 02 parts by weight and 0.1 parts by weight of dibutyltin dimethoxide into a universal mixer and degassing and mixing.

Example 2 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% isostearic acid treated calcium carbonate (particle size 0.1
0 μm) 50 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, and dibutyltin dimethoxide 0.1 parts by weight were charged in a universal mixer, and a sample obtained by defoaming and mixing was used. An H-type test piece was obtained.

Example 3 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% oleic acid treated calcium carbonate (particle size 0.10μ
m) 25 parts by weight, rosin acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25 parts by weight, methyltrimethoxysilane 5 parts by weight, polypropylene glycol 0.02 parts by weight, dibutyltin dimethoxide 0.1 parts by weight. Part was placed in a universal mixer and degassed and mixed to obtain a sample
A mold test body was obtained.

[Example 4] α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% isostearic acid treated calcium carbonate (particle size 0.1
0 μm) 50 parts by weight, 5 parts by weight of methyltrimethoxysilane, 0.02 parts by weight of polypropylene glycol, and 0.5 parts by weight of tetrabutoxytitanate were charged in a universal mixer, and defoamed and mixed to obtain an H-type sample. A test body was obtained.

Example 5 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% oleic acid treated calcium carbonate (particle size 0.10μ
m) 25 parts by weight, isostearic acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, dibutyltin dimethoxide 0. An H-type test body was obtained using a sample obtained by charging 1 part by weight into a universal mixer and degassing and mixing.

Example 6 α, ω-with a viscosity of 100,000 cSt
2.3% treated calcium carbonate (particle size 0.10 μm) treated with a mixture of dihydroxydimethylpolysiloxane 60 parts by weight and a mixture of stearic acid and oleic acid in a ratio of 4 parts by weight to 6 parts by weight as a treating agent 50 Parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, and dibutyltin dimethoxide 0.1 parts by weight were charged into a universal mixer and defoamed and mixed to obtain a H-type sample. A test body was obtained.

Comparative Example 1 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% of stearic acid treated calcium carbonate (particle size 0.10μ
m) 50 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.
An H-type test body was obtained using a sample obtained by charging 02 parts by weight and 0.1 parts by weight of dibutyltin dimethoxide into a universal mixer and degassing and mixing.

[Comparative Example 2] α, ω-with a viscosity of 100,000 cSt
2.3% treated calcium carbonate (particle size 0.10 μm) 50 treated with 60 parts by weight of dihydroxydimethylpolysiloxane and a mixture of stearic acid and oleic acid in a ratio of 6 parts by weight to 4 parts by weight as a treating agent Parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, and dibutyltin dimethoxide 0.1 parts by weight were charged into a universal mixer and defoamed and mixed to obtain a H-type sample. A test body was obtained.

[Comparative Example 3] α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.7% oleic acid treated calcium carbonate (particle size 0.10μ
m) 50 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.
An H-type test body was obtained using a sample obtained by charging 02 parts by weight and 0.1 parts by weight of dibutyltin dimethoxide into a universal mixer and degassing and mixing.

Next, the room temperature-curable organopolysiloxane composition obtained above was tested in accordance with the method of tensile adhesion and durability grade 10030 of JIS A-5758. As the adherend having tensile adhesiveness, float glass, JIS aluminum, fluororesin-coated aluminum, and acrylic electrodeposition-coated steel sheet were used. As for the evaluation results, except for Comparative Example 7, the test was performed using a non-primer. As for the evaluation result, regarding the tensile adhesiveness, the rate of cohesive failure of the composition was visually confirmed in the failure state. Regarding the durability, the state after the test was visually confirmed. The results are shown in Tables 1 to 3.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

[Table 3]

Example 7 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% oleic acid treated calcium carbonate (particle size 0.10μ
m) 25 parts by weight, rosin acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, γ-aminopropyltriethoxy. 0.5 parts by weight of silane and 0.1 parts by weight of dibutyltin dimethoxide were charged in a universal mixer and defoamed and mixed to obtain an H-type test sample.

Example 8 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% isostearic acid treated calcium carbonate (particle size 0.1
0 μm) 25 parts by weight, rosin acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, dibutyltin dimethoxide 0. 1 part by weight and 0.5 part by weight of γ-aminopropyltriethoxysilane were charged into a universal mixer and defoamed and mixed to obtain an H-type test sample.

Example 9 α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% oleic acid treated calcium carbonate (particle size 0.10μ
m) 25 parts by weight, rosin acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25 parts by weight, methyltrimethoxysilane 5 parts by weight, polypropylene glycol 0.02 parts by weight, dibutyltin dimethoxide 0.1 parts by weight. Part, γ-
Using 0.2 parts by weight of aminopropyltriethoxysilane in a universal mixer and degassing and mixing, a sample obtained
A mold test body was obtained.

Example 10 α, ω having a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% isostearic acid treated calcium carbonate (particle size: 0.
10 μm) 25 parts by weight, rosin acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25 parts by weight, methyltrimethoxysilane 5 parts by weight, polypropylene glycol 0.1.
02 parts by weight, tetrabutoxy titanate 0.5 parts by weight,
0.5 parts by weight of γ-aminopropyltriethoxysilane was charged into a universal mixer and defoamed and mixed to obtain an H-type test sample.

[Embodiment 11] α, ω having a viscosity of 100,000 cSt
-Dihydroxydimethylpolysiloxane 60 parts by weight, oleic acid 2.3% treated calcium carbonate (particle size 0.10μ
m) 10 parts by weight, isostearic acid 2.3% treated calcium carbonate (particle size 0.10 μm) 15 parts by weight, rosin acid 2.3% treated calcium carbonate (particle size 0.10 μm) 25
Parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.02 parts by weight, dibutyltin dimethoxide 0.1 parts by weight, γ-aminopropyltriethoxysilane 0.5 parts by weight were charged into a universal mixer. An H-type test body was obtained using the sample obtained by degassing and mixing.

[Example 12] α, ω having a viscosity of 100,000 cSt
-2.3% treated calcium carbonate treated with a mixture of 60 parts by weight of dihydroxydimethylpolysiloxane and 6 parts by weight of stearic acid and oleic acid as a treating agent (particle size 0.10 μm) 25 parts by weight, calcium carbonate treated with 2.3% rosin acid (particle size 0.10μ
m) 25 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.
An H-type test body was obtained using a sample obtained by charging 02 parts by weight, 0.1 part by weight of dibutyltin dimethoxide and 0.5 part by weight of γ-aminopropyltriethoxysilane into a universal mixer and degassing and mixing. It was

[Comparative Example 4] α, ω-with a viscosity of 100,000 cSt
60 parts by weight of dihydroxydimethylpolysiloxane, 2.3% of stearic acid treated calcium carbonate (particle size 0.10μ
m) 50 parts by weight, vinyltris (methylethylketoxime) silane 6 parts by weight, polypropylene glycol 0.
An H-type test body was obtained using a sample obtained by charging 02 parts by weight, 0.1 part by weight of dibutyltin dimethoxide and 0.5 part by weight of γ-aminopropyltriethoxysilane into a universal mixer and degassing and mixing. It was

[0057]

Comparative Example 5 60 parts by weight of α, ω-dihydroxydimethylpolysiloxane having a viscosity of 100,000 cSt, 50% by weight of calcium carbonate (particle size 0.10 μm) treated with 2.3% resin acid, vinyltris (methylethylketoxime) Sample obtained by charging 6 parts by weight of silane, 0.02 part by weight of polypropylene glycol, 0.1 part by weight of dibutyltin dimethoxide and 0.5 part by weight of γ-aminopropyltriethoxysilane into a universal mixer and degassing and mixing. Was used to obtain an H-type test body.

Comparative Example 6 60 parts by weight of α, ω-dihydroxydimethylpolysiloxane having a viscosity of 100,000 cSt, 50 parts by weight of calcium carbonate (particle size 0.10 μm) treated with 2.7% of oleic acid, vinyltris (methylethylketoxime). Sample obtained by charging 6 parts by weight of silane, 0.02 part by weight of polypropylene glycol, 0.1 part by weight of dibutyltin dimethoxide and 0.5 part by weight of γ-aminopropyltriethoxysilane into a universal mixer and degassing and mixing. Was used to obtain an H-type test body.

Next, the room temperature curable organopolysiloxane composition thus obtained was evaluated in the same manner as in Example 1 above. The results are shown in Tables 4-6.

[0061]

[Table 4]

[0062]

[Table 5]

[0063]

[Table 6]

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Yokoo 1 Hitomi, Osamu Matsuida-cho, Usui-gun, Gunma Prefecture 10 Shin-Etsu Chemical Co., Ltd. Silicone Materials Research Laboratory (72) Inventor Masaharu Sato Matsui, Usui-gun, Gunma Prefecture Tamachi Daiji Hitomi 1-10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (56) Reference JP-A-3-33564 (JP, A) JP-A-3-17158 (JP, A) (58) Survey Fields (Int.Cl. ⁷ , DB name) C08L 83/06 C08K 5/54 C08K 9/04 C08K 3/26

Claims (4)

(57) [Claims] 1. (A) The following general formula (1): (Wherein R ¹ are the same or different from each other, unsubstituted or substituted monovalent hydrocarbon groups, and n is an integer of 2 or more.) 100 parts by weight of diorganopolysiloxane, (B) 1 molecule 0.2 to 30 parts by weight of an organosilicon compound having at least three hydrolyzable groups, and (C) at least one structure selected from an aliphatic unsaturated bond, a branched structure, and an ether bond in the molecule. 10 to 200 parts by weight of calcium carbonate treated with one or more treating agents selected from carboxylic acids having 8 or more carbon atoms, the treated amount being 1 to 2.5% by weight. A room-temperature-curable organopolysiloxane composition for a working joint, which is excellent in stress relaxation. 2. (A) The following general formula (1): (Wherein R ¹ are the same or different from each other, unsubstituted or substituted monovalent hydrocarbon groups, and n is an integer of 2 or more.) 100 parts by weight of diorganopolysiloxane, (B) 1 molecule 0.2 to 30 parts by weight of an organosilicon compound having at least three hydrolyzable groups, and (C) at least one structure selected from an aliphatic unsaturated bond, a branched structure, and an ether bond in the molecule. 10 to 200 parts by weight of calcium carbonate treated with one or more treating agents selected from carboxylic acids having 8 or more carbon atoms, the treated amount being 1 to 2.5% by weight. (D) Calcium carbonate treated with a carboxylic acid having no aliphatic unsaturated bond, branched structure, or ether bond in the molecule and having a melting point of 100 ° C. or higher, the treatment amount being 1 ~ 2 For working joints, characterized in that excellent stress relaxation and comprising containing 5 10-200 parts by weight of calcium carbonate in weight percent RTV organopolysiloxane composition. 3. The average particle size of calcium carbonate is 0.01 to.
The composition according to claim 1, which has a thickness of 0.2 μm. 4. JIS A-5758 without a primer
4. The composition according to claim 1, 2 or 3 which gives a cured product which passes the durability grade of 10030 of.