JPH0539421A - Room temperature-curable organopolysiloxane composition having mildew resistance - Google Patents

Abstract

PURPOSE:To obtain the subject composition capable of effectively suppressing the proliferation of various kinds of fungi over a long period and cured product thereof. CONSTITUTION:(A) 100 pts.wt. diorganopolysiloxane expressed by the formula [R<2> is (substituted) monovalent hydrocarbon; (n) is positive integer] is blended with (B) 0.2-30 pts.wt., preferably 0.5-20 pts.wt. organosilicon compound (e.g. methyltrimethoxysilane) having >=3 hydrolyzable groups (e.g. alkoxy group, ketoxime group, amino group or a alpha-silylester group) in one molecule and (C) 0.1-20 pts.wt., preferably 0.25-5 pts.wt. compound (e.g. Me2C=N-O-H, etc.) having >=1 hydroxyimono group bound to a carbon atom in one molecule, and the resultant composition is cured.

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 a cured product thereof, and is particularly excellent in antifungal property. A room temperature curable organopolysiloxane composition and a cured product thereof.

[0002]

2. Description of the Related Art Conventionally, room-temperature-curable organopolysiloxane compositions, which are easily cured by moisture to form rubber elastic bodies, have been widely used in applications such as adhesives, coating materials, electrical insulating sealing materials, and sealing materials for construction. It is used. However, this type of composition has a problem that the mold adheres to the surface and propagates and the appearance is impaired during long-term use.

In order to prevent such mold attachment and reproduction, a method is known in which a mold preventive agent is added to the above composition to suppress the growth of mold. For example, a method of adding 2,3,5,6-tetrachloro-4-methylsulfonylpyridine (JP-A-51-106158), a method of adding 2- (4-thiazolyl) -benzimidazole (JP-A-51-106158). 54-127960 JP), N- method of adding a substituted benzimidazolyl carbamate derivative (JP 56-38348 JP), the following _{formula, R-Ph-SO 2 -C} (R ') 2 -I ( wherein , R is hydrogen, halogen or an alkyl group having 1 to 4 carbon atoms, and R'is hydrogen, iodine or an alkyl group having 1 to 4 carbon atoms). 56-127658), a method of adding a triorganotin compound (JP-A-56-133150, JP-A-57-96044).
JP-A-60-18693), a method of adding benzimidazolyl-alkyl-carbamate (JP-A-60-18693), and a method of adding tetraalkylthiuram disulfide (JP-A-60-18693).
No. 60-115660) and the like are known.

[0004]

However, in the conventional methods, the types of molds that can prevent reproduction are limited, and it is difficult to maintain the effect for a long period of time. Accordingly, it is an object of the present invention to provide a room temperature curable organopolysiloxane composition in which the growth of a wide variety of molds is effectively suppressed over a long period of time, and a cured product thereof.

[0005]

A means to achieve Namely, the present invention is, (a) the following general formula (1): HO- [Si ( R 1) 2 O] n -H (1) ( In the formula, R ^1, Diorganopolysiloxane, which may be the same or different, is a substituted or unsubstituted monovalent hydrocarbon group, and n is a positive integer, and (b) is hydrolyzable in one molecule. A room temperature curable organopolysiloxane composition comprising an organosilicon compound having at least two groups, and (c) a compound having at least one hydroxyimino group bonded to a carbon atom in one molecule.

(A) Diorganopolysiloxane In the present invention, as the base polymer, the above-mentioned general formula
(1), ^{i.e., HO- [Si (R 1)} 2 O] n -H (1) ( wherein, R ¹ and n are the street) diorganopolysiloxane represented by is used. In the general formula (1), the monovalent hydrocarbon group R ¹ has 1 to 1 carbon atoms.
Those of 0, especially those of 1-8 are preferable. Specifically, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, and a hexyl group, an aryl group such as a phenyl group and a tolyl group, an alkenyl group such as a vinyl group, an allyl group, a butenyl group, and a hexenyl group; Groups such as cycloalkyl groups such as groups, benzyl groups, aralkyl groups such as 2-phenylethyl groups, and groups in which some or all of the hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms, cyano groups, etc., such as chloro. Examples thereof include a methyl group, a trifluoropropyl group and a cyanoethyl group.

In the general formula (1), n is a number corresponding to the degree of polymerization, and is 50 to 20 in terms of viscosity and workability.
It is preferably an integer in the range of 00. Like this (a)
Specific examples of the component diorganopolysiloxane include those represented by the following chemical formulas.

HO- (SiMe ₂ O) _p -H, HO- (SiMe ₂ O) _p- (SiPh ₂ O) _q -H, HO- (SiMe ₂ O) _p- [Si (Me) (C ₂ H ₄ CF ₃ ) O] _q -H, HO- (SiMe ₂ O) _p- [Si (Me) (CH = CH ₂ ) O] _q -H (In the above formula, Me is a methyl group and Ph is a phenyl group. Yes, p
And q are positive integers, respectively, and p + q is an integer corresponding to n. )

(B) Organosilicon compound having a hydrolyzable group
The organosilicon compound of the substance (b) needs to have at least three hydrolyzable groups, and the composition of the present invention can be cured at room temperature in the presence of water by blending such components.

Examples of the hydrolyzable group include alkoxy groups such as methoxy group, ethoxy group, propoxy group, butoxy group, methoxyethoxy group and ethoxyethoxy group: propenoxy group, isopropenoxy group, isobutenyloxy group, 1 -Alkenyloxy group such as ethyl-2-methylvinyloxy group: dimethylketoxime group, methylethylketoxime group, diethylketoxime group, cyclopentanoxime group, ketoxime group such as cyclohexanoxime group: acetoxy group, propionoxy group, Acyloxy group such as butyroyloxy group, benzoyl group: N-
Amino group such as methylamino group, N-ethylamino group, N-propylamino group, N-butylamino group, N, N-dimethylamino group, N, N-diethylamino group and cyclohexylamino group: N-methylacetamide group , N-ethylacetamide group, N-methylbenzamide group and other amide groups: N, N-dimethylaminoxy group, N, N-diethylaminoxy group and other aminoxy groups: Isocyanate group: α-silyl ester group: Chlorine atom Halogen atom such as: and the like.
However, if a halogen atom such as a chlorine atom is used as the hydrolyzable substance, hydrogen halide having severe corrosiveness and toxicity is generated during the hydrolysis reaction, which is dangerous, so it should be noted with caution. Is.

The group other than the hydrolyzable group bonded to the silicon atom of the organosilicon compound of the component (b) is a substituted or unsubstituted monovalent hydrocarbon group similar to R ^{1 in the} component (a) described above. Is preferred. The monovalent hydrocarbon group has 1 carbon atom from the viewpoint of easy synthesis.
Preferred are an alkyl group having 8 to 8, an alkenyl group having 2 to 10 carbon atoms and a phenyl group.

Containing the hydrolyzable groups mentioned above
As the organosilicon compound (b), specifically, methyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, 3-chloropropyl. Alkoxysilanes such as trimethoxysilane, methyltriisopropenoxysilane, vinyltriisopropenoxysilane, enoxysilanes such as phenyltriisopropenoxysilane, methyltris (methylethylketoxime) silane, vinyltris (methylethylketoxime) silane, phenyltris (methylethylketo). Oxime) silane, methyltris (dimethylketoxime) silane, ketoximesilane such as tetrakis (methylethylketoxime) silane, methyltria Acetoxysilanes such as toxysilane, vinyltriacetoxysilane, phenyltriacetoxysilane, tetraacetoxysilane, methyltris (N-butylamino) silane, vinyltris (N-hexylamino) silane, phenyltris (N, N-diethylamino) silane, etc. Amidosilanes such as aminosilane, methyltris (N-methylacetamido) silane, vinyltris (N-ethylacetamido) silane, methyltris (N, N-diethylaminoxy) silane, vinyltris (N,
Examples include aminoxysilanes such as N-diethylaminoxy) silane, and partial hydrolysates of these organosilicon compounds.

The amount of component (b) used is preferably 0.2 to 30 parts by weight per 100 parts by weight of the diorganopolysiloxane of component (a). It is more preferably 0.5 to 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 will be impaired.

(C) The compound of the compound (c) having a hydroxyimino group has at least one hydroxyimino group bonded to a carbon atom in one molecule, and such a compound is represented by an oxime compound. That is, such a compound having a hydroxyimino group has a strong antibacterial property against most molds, and in the present invention, by incorporating such a compound, many molds are generated over an extremely long period of time. It succeeded in suppressing effectively.

In the present invention, such compounds include, for example, the following general formulas (2) to (6):

[Chemical 1]

[Chemical 2]

[Chemical 3]

[Chemical 4]

[Chemical 5] In the above formulas (2) to (6), R ² , R ³ , R ⁷ and R ⁸
Are each a hydrogen atom or substituted or unsubstituted 1
Valent hydrocarbon group such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, t-butyl group, pentyl group, alkyl group such as hexyl group, phenyl group, aryl group such as tolyl group, vinyl group, Alkenyl groups such as allyl groups, cycloalkyl groups such as cyclohexyl groups, aralkyl groups such as benzyl groups and β-phenylethyl groups, or chloromethyl groups in which some or all of these groups are substituted with halogen atoms, cyano groups, etc. , A trifluoropropyl group, a cyanoethyl group, and the like having 1 to 10 carbon atoms, and R ² and R ³ , and R ⁷ and R ⁸ may be the same or different. Also R ⁴ , R ⁵ and R
⁶ is a substituted or unsubstituted divalent hydrocarbon group having 2 to 10 carbon atoms, such as ethylene group, propylene group, tetramethylene group, pentamethylene group, hexamethylene group, methylethylene group, methyl group An alkylene group such as a propylene group, or a tetrafluoroethylene group in which some or all of the hydrogen atoms of these groups are substituted with a halogen atom, a cyano group, or the like. Also the above formula
In (5), R ⁵ and R ⁶ may be the same or different from each other.

In the present invention, as the component (c) particularly suitably used, for example, Me ₂ C = NOH, Me
(Et) C = NOH, Me (Ph) C = NOH, Ph ₂ C = NOH, PhHC = N
-OH and the following formulas (7) to (11):

[Chemical 6]

[Chemical 7]

[Chemical 8]

[Chemical 9]

[Chemical 10] (Wherein Me represents a methyl group, Et represents an ethyl group, and Ph represents a phenyl group).

The amount of component (c) used is preferably 0.1 to 20 parts by weight, more preferably 0.25 to 5 parts by weight, per 100 parts by weight of component (a). If this amount is too small, the resulting composition has insufficient antibacterial properties, and if it is too large, the cured product obtained by curing the composition causes poor curing, resulting in impaired performance as a sealing material. turn into. Further, when the component (c) is blended, it is possible to blend one kind or two or more kinds thereof.

Condensation Catalysts Generally, the time required for a condensation curable organopolysiloxane composition such as the composition of the present invention to cure is relatively long. When shortening this curing time, a condensation catalyst is usually used. As the condensation catalyst used in the present invention, those conventionally used may be used, for example, dibutyltin dimethoxide, dibutyltin diacetate, dibutyltin dioctoate, dibutyltin dilaurate, dimethyltin dimethoxide, dimethyltin dioxide. Organic tin compounds such as acetate, tetrapropyl titanate, tetrabutyl titanate, tetra-2-ethylhexyl titanate, organic titanium compounds such as dimethoxytitanium diacetylacetonate, hexylamine, 3-aminopropyltrimethoxysilane, tetramethylguanidylpropyl An amine compound such as trimethoxysilane and a salt thereof can be used alone or in combination of two or more.

The amount of the condensation catalyst used is generally the above-mentioned component (a).
It is preferably 10 parts by weight or less, more preferably 0 to 5 parts by weight, per 100 parts by weight. If the amount of the condensation catalyst used is too large, the resulting cured product will be poorly cured, and the performance as a sealing material will be impaired.

Other compounding agents In the composition of the present invention, if necessary, various compounding agents such as fillers, pigments, dyes, adhesion promoters, thixotropy improvers, rust preventives, other than the component (c) Antifungal agents, flame retardants, etc. may be added.

[0021]

Example 1 100 parts by weight of α, ω-dihydroxydimethylpolysiloxane having a viscosity of 20,000 cSt at 25 ° C., 2.0 parts by weight of cyclohexanone oxime, 2.0 parts by weight of anatase-type titanium oxide, and surface treatment with dimethyldichlorosilane. 10 parts by weight of fumed silica was charged into a universal mixer and mixed to obtain a base compound. 5.0 parts by weight of methyltriacetoxysilane was mixed with this base compound at room temperature under reduced pressure to obtain an organopolysiloxane composition. This composition was molded into a sheet with a thickness of 2 mm, and the temperature was 20 ° C and 55%.
It was cured at RH for 7 days to obtain a cured product. This cured product was cut into a disk with a diameter of 3 cm, and the cured product was treated with running tap water for 1 week to remove by-products generated by curing, and used as a sample piece. JIS-Z-2911 The mold resistance test was carried out in accordance with. That is, first, the diameter 9
A glass dish of cm was filled with potato dextrose agar, and the sample piece prepared above was placed in the center.
Next, Aspergillus niger, Penicillium citrus, Rhizopus niglycans, Cladosporium
A mold spore suspension of Herbalum and Ketomium globosum was uniformly sprayed on the sample, and the dish was covered. When the petri dish was left in a thermo-hygrostat at a temperature of 28 ° C and a relative humidity of 98% for 56 days, the test piece was examined and no mold was found at all.

Example 2 An organopolysiloxane composition was prepared in the same manner as in Example 1 except that 1.2 parts by weight of dimethylglyoxime was used instead of 2.0 parts by weight of cyclohexanone oxime, and a cured product thereof was prepared. Got Further, using the obtained cured product, a mold resistance test was carried out in the same manner as in Example 1, and no mold was found at all.

Comparative Example 1 A composition was obtained in the same manner as in Example 1 except that cyclohexanone oxime was not added. A mold resistance test was conducted using the obtained composition in the same manner as in Example 1. As a result, mold propagation was observed over almost the entire area.

Example 3 100 parts by weight of α, ω-dihydroxydimethylpolysiloxane having a viscosity of 20,000 cSt at 25 ° C., 1.5 parts by weight of cyclohexanedione dioxime, 0.1 part by weight of dibutyltin dimethoxide, and fat having an average particle size of 0.04 μm. 100 parts by weight of calcium carbonate which had been surface-treated with acid soap was charged into a universal mixer and mixed to obtain a base compound. To this base compound, 6.0 parts by weight of vinyltrimethoxysilane was mixed at room temperature under reduced pressure to obtain the desired composition. A cured product was obtained from the obtained composition in the same manner as in Example 1, and a mold resistance test was conducted in the same manner as in Example 1 using the obtained cured product. As a result, no mold was found. There wasn't.

Example 4 Curing was performed in the same manner as in Example 3 except that 2.0 parts by weight of benzophenone oxime was used instead of cyclohexanedione dioxime and 9.0 parts by weight of 2-butanoxime silane was used instead of vinyltrimethoxysilane. I got a thing. Further, a mold resistance test was conducted in the same manner as in Example 1 using the obtained cured product, and no mold was found at all.

Comparative Example 2 A cured product was obtained in the same manner as in Example 3 except that cyclohexanedione dioxime was not added. Further, a mold resistance test was conducted using the obtained cured product in the same manner as in Example 1, and as a result, mold reproduction was observed over almost 2/3 of the entire area.

Comparative Example 3 A cured product was obtained in the same manner as in Example 4 except that benzophenone oxime was not added. Further, a mold resistance test was conducted using the obtained cured product in the same manner as in Example 1, and as a result, mold reproduction was observed over almost 2/3 of the entire area.

[0028]

INDUSTRIAL APPLICABILITY The room temperature curable organopolysiloxane composition of the present invention effectively suppresses the growth of a wide variety of molds over a long period of time.

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[Procedure amendment]

[Submission date] April 21, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

(B) Organosilicon compound having a hydrolyzable group
The organosilicon compound of the substance (b) needs to have at least two hydrolyzable groups, and the composition of the present invention is cured at room temperature in the presence of water by blending such components.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Examples of the hydrolyzable group include alkoxy groups such as methoxy group, ethoxy group, propoxy group, butoxy group, methoxyethoxy group and ethoxyethoxy group: propenoxy group, isopropenoxy group, isobutenyloxy group, 1 -Alkenyloxy groups such as ethyl-2-methylvinyloxy group: dimethylketoxime group, methylethylketoxime group, diethylketoxime group, cyclopentanoxime group, cyclohexanoxime group and other ketoxime groups: acetoxy group, propionyloxy group ,
Butylyloxy group, acyloxy group such as benzoyloxy group: N-methylamino group, N-ethylamino group, N-propylamino group, N-butylamino group, N, N-dimethylamino group, N, N-diethylamino group, Amino group such as cyclohexylamino group: N-methylacetamide group, N-ethylacetamide group, N-methylbenzamide group or other amide group:
Examples include aminoxy groups such as N, N-dimethylaminoxy group and N, N-diethylaminoxy group: isocyanato group: α-silyl ester group: halogen atom such as chlorine atom. However, if a halogen atom such as a chlorine atom is hydrolyzable, hydrogen halide with severe corrosiveness and toxicity is generated during the hydrolysis reaction, so it is dangerous. Should.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

Containing the hydrolyzable groups mentioned above
As the organosilicon compound (b), specifically, methyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, 3-chloropropyl. Alkoxysilanes such as trimethoxysilane, methyltriisopropenoxysilane, vinyltriisopropenoxysilane, alkenyloxysilanes such as phenyltriisopropenoxysilane, methyltris (methylethylketoxime) silane, vinyltris (methylethylketoxime) silane, phenyltris (Methylethylketoxime) silane, methyltris (dimethylketoxime) silane, ketoximesilane such as tetrakis (methylethylketoxime) silane, methyl Triacetoxysilane, vinyl triacetoxy silane, phenyl triacetoxy silane, acetoxy silane, such as tetraacetoxysilane,
Aminosilanes such as methyltris (N-butylamino) silane, vinyltris (N-hexylamino) silane, phenyltris (N, N-diethylamino) silane, methyltris (N-methylacetamido) silane, vinyltris (N-
Amidosilanes such as ethylacetamide) silane, aminotrisilanes such as methyltris (N, N-diethylaminoxy) silane, vinyltris (N, N-diethylaminoxy) silane, and partial hydrolysates of these organosilicon compounds.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazutoshi Fujioka 2-13-1, Isobe, Annaka-shi, Gunma Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (72) Inventor Koji Moriyama Kitakyushu, Fukuoka 2-1-1 Nakajima, Kokurakita-ku, Tochi, Ltd. (72) Inventor Akihiro Kawaguchi 2-1-1, Nakajima, Kokurakita-ku, Kitakyushu, Fukuoka Prefecture (72) Inventor Hasuike Kan 2-8-1, Motomura, Chigasaki, Kanagawa Tochiki Co., Ltd., Chigasaki Plant (72) Inventor Kazuo Takahashi 2-8-1, Motomura, Chigasaki, Kanagawa Tochiki, Chigasaki Plant

Claims (2)

[Claims] 1. A (a) the following general formula (1): HO- [Si ( R 1) 2 O] n -H (1) ( In the formula, R ^1, which may be identical or different, substituted or non A substituted monovalent hydrocarbon group, and n is a positive integer.), (B) an organosilicon compound having at least three hydrolyzable groups in one molecule, (c) A room temperature curable organopolysiloxane composition containing a compound having at least one hydroxyimino group bonded to a carbon atom in one molecule. 2. A cured product obtained by curing the composition according to claim 1.