JP3181791B2 - Silicone aqueous emulsion composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicone-based aqueous emulsion composition. The composition of the present invention is useful as a coating agent and the like.

[0002]

2. Description of the Related Art Conventionally, an aqueous silicone emulsion composition which cures to form a rubber film is known from various compositions. For example, a silicone emulsion composition comprising an anionically stabilized hydroxylated diorganopolysiloxane, colloidal silica and an organotin compound or an organic amine compound and having a pH in the range of 9 to 11.5 (JP-A-56-16553) However, this composition has a problem that it has poor adhesion to various substrates and is subject to various restrictions when used due to its strong alkalinity.

In order to improve the adhesiveness of this type of composition, for example, a cyclic organosiloxane and a functional group-containing organotrialkoxysilane such as an aminoalkyltrialkoxysilane are mixed with a sulfonic acid or quaternary ammonium salt. Organopolysiloxane latex composition prepared by emulsion polymerization in the presence of a surfactant (JP-A-54-131661)
JP-A No. 2000-131, a silicone latex composition comprising a siloxane block copolymer composed of dimethylsiloxane units and monophenylsiloxane units, water, a cationic surfactant, a nonionic surfactant, a filler and an aminofunctional silane (US Pat. No. 3,817,894), a silicone aqueous emulsion composition comprising a hydroxyl group-containing organopolysiloxane emulsion, a reaction product of an aminofunctional silane and an acid anhydride, colloidal silica and a curing catalyst (see Japanese Patent Application Laid-Open No. 58-1).
No. 01153) has been proposed. However, in each case, although some effect of improving the adhesiveness is recognized, it is still insufficient, and a large force is partially applied including the weak film strength. At present, it cannot always be said that it is always sufficient for use under severe conditions such as sealing of the fabric or increasing the strength of a sewn portion of the fiber.

[0004]

SUMMARY OF THE INVENTION Under the circumstances described above, the present invention relates to a silicone-based aqueous emulsion composition, which is easily cured at room temperature by removing water, and has a strength and
An object of the present invention is to provide a rubber film having excellent flexibility and good adhesion to various substrates.

[0005]

Means for Solving the Problems The aqueous silicone emulsion composition of the present invention has solved the above-mentioned problems.

Embedded image [Wherein, R ¹ is the same or different, unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, Z is R ¹ , OR ² or (OSiR ¹ R ¹ ) _k OR ²
R ² is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, k is 0 to 1,00
X represents an identical or different group represented by R ¹ or OR ² ; m represents an integer of 100 to 10,000; n represents an integer of 0 to 1,000]; 100 parts by weight of an organopolysiloxane containing an OR ² group, (B) a hydroxy group and / or an alkoxy group in the organopolysiloxane containing at least two Si—H bonds in one molecule, When two groups are present in one molecule, 0.5 to 50 parts by weight of an organopolysiloxane containing at least three Si-H bonds in one molecule, (C) 0.5 to 100 parts by weight of colloidal silica , (D ) Amido- and carboxyl-containing organoalkoxysilanes and / or partial hydrolysis condensates thereof 0.1 to 20 parts by weight, (E) Epoxy or amino group-containing organoalkoxysilanes and / or partial hydrolysis condensates 0.1 to 20 parts by weight 20 parts by weight, (F Cure catalyst 0.01 to 10 parts by weight is made as a main component.

Hereinafter, the present invention will be described in more detail. First, R ^{1 of the} organopolysiloxane represented by the general formula (1) as the component (A) is the same or different and is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms. Saturated aliphatic hydrocarbon groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, tetradecyl, octadecyl, unsaturated aliphatic hydrocarbon groups such as vinyl and allyl, cyclopentyl, cyclohexyl, etc. A saturated alicyclic hydrocarbon group, an aromatic hydrocarbon group such as phenyl, tolyl or naphthyl, and / or
Or a group in which a hydrogen atom bonded to a carbon atom of these groups is partially substituted with a halogen atom or an organic group containing an epoxy group, a carboxyl group, an amino group, a methacryl group, or the like. R ² is a hydrogen atom and / or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms. Examples of the group other than the hydrogen atom include the same groups as R ¹ . X is the same or different group represented by R ¹ or OR ² . Z is the same or different group represented by R ¹ , OR ² or (OSiR ¹ R ¹ ) _k OR ² . k is an integer from 0 to 1,000. m is an integer of 100 to 10,000. If it is less than 100, the flexibility becomes poor, and if it is more than 10,000, the tear strength decreases. Preferably it is an integer of 1,000 to 5,000.
n is an integer from 0 to 1,000, and if it is greater than 1,000, the flexibility is insufficient. Preferably, it is an integer of 0 to 100. However, from the viewpoint of a crosslinking reaction with an organopolysiloxane containing a Si-H bond described below, at least two
Must contain ^two OR groups. The siloxane skeleton may contain a branching unit.

Specific examples of such organopolysiloxanes include the following.

Embedded image

[0008]

Embedded image

Such an organopolysiloxane can be synthesized by a known method. For example, a cyclic siloxane such as octamethyltetrasiloxane and α, ω- can be synthesized in the presence of a catalyst such as an alkali metal hydroxide. An equilibrium reaction between the hydroxypolysiloxane oligomer and the organoalkoxysilane yields an organopolysiloxane having a hydroxy group or an alkoxy group, respectively. In addition, the above-mentioned organopolysiloxane is used as an emulsion in a known emulsion polymerization method, that is, after cyclic siloxane, organoalkoxysilane or the like is previously emulsified and dispersed in water using an anionic surfactant or a cationic surfactant, Accordingly, the catalyst can be easily synthesized by adding a catalyst such as an acid or an alkaline substance to carry out a polymerization reaction.

The organoalkoxysilane in the case of the above-mentioned emulsion polymerization is represented by the general formula R ¹ _p Si (OR ² ) _4-p wherein R ¹ and R ² are the same as above, and p is 0,
1 or 2], and specific examples include dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and γ.
-Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl)-
γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, tetraethoxysilane and the like can be mentioned. In the present invention, the organopolysiloxane of the component (A) is preferably used in the form of an emulsion.

Next, the organopolysiloxane containing at least two Si—H bonds in one molecule of the component (B) is:
(A) A component that acts as a crosslinking agent for the organopolysiloxane as a component to improve the film strength, improve the adhesion to the substrate, and further improve the flame retardancy when treated into fibers. , General formula

Embedded image (Wherein R ¹ is the same as above, Y is a hydrogen atom or R ¹ , a is a positive number from ¹ to 1,000, b is a positive number from 0 to 1,000, and b = 0
In the above case, Y is a hydrogen atom, and when b = 1, at least one of Y is a hydrogen atom). However, when the number of hydroxy groups and / or alkoxy groups in the organopolysiloxane as the component (A) is two in one molecule, at least three Si-H bonds are formed in one molecule from the viewpoint of crosslinkability. It is necessary to contain. The siloxane skeleton may contain a branch unit.

Specific examples of such an organopolysiloxane include the following.

Embedded image

This organopolysiloxane, like the above-mentioned organopolysiloxane of the component (A), is obtained by equilibrating or emulsion-polymerizing a Si-H-containing cyclic siloxane with hexamethyldisiloxane or tetramethyldihydrogendisiloxane. Alternatively, it can be synthesized by a conventionally known method by a cohydrolytic condensation reaction of methyldichlorosilane, trimethylchlorosilane, dimethylchlorosilane, or the like. In the present invention, the organopolysiloxane of the component (B) is preferably used in the form of an emulsion. The amount of the component (B) is 0.5 to 50 parts by weight based on 100 parts by weight of the component (A). If the amount is less than 0.5 part by weight, the crosslinkability is insufficient, the strength of the silicone rubber film decreases, and the adhesiveness decreases. When the amount exceeds 50 parts by weight, the coating becomes too hard and the flexibility is reduced, preferably 1 to 30 parts by weight.

Next, the colloidal silica of the component (C) is
Improves the strength of silicone rubber film as a reinforcing component,
And a component for improving the flame retardancy, the form of an emulsion which is emulsified and dispersed in water using colloidal silica is preferred. After previously mixing with the organopolysiloxane of the component (A) or (B), the emulsion may be dispersed in water using a surfactant. Alternatively, the general formula R ¹ _q S
After emulsifying and dispersing an organoalkoxysilane represented by i (OR ² ) _4-q [wherein R ¹ and R ² are the same as above and q is 0 or 1] using a surfactant, alkali It can also be synthesized by adding a catalyst such as a metal hydroxide to carry out a hydrolytic condensation reaction. The amount of the component (C) is (A)
0.5 to 100 parts by weight per 100 parts by weight of the component, 0.5
If the amount is less than 100 parts by weight, there is no effect of improving the strength and flame retardancy of the silicone rubber film. If the amount is more than 100 parts by weight, the film becomes hard and brittle, and elongation and flexibility are reduced. Preferably it is 1 to 50 parts by weight.

Next, the organoalkoxysilane containing an amide group and a carboxy group and / or a partially hydrolyzed condensate thereof as the component (D) is a component for improving the adhesion between the silicone rubber film and the substrate. , An aminoalkoxysilane and / or a partially hydrolyzed condensate thereof and a dicarboxylic anhydride. Aminoalkoxysilane as a starting material for obtaining the component (D) is represented by the general formula AR ¹ _r Si (OR ² ) _3-r
R ^1, R ² are as defined above, A is the formula ^{-R 3 (NR 2 R 3)} s NR 2 2 ( in the formula,
R ³ is the same or different, unsubstituted or substituted divalent hydrocarbon group having 1 to 6 carbon atoms, and R ² is the same as described above, but at least one is a hydrogen atom. ,
r is represented by 0, 1 or 2], and specific examples thereof include the following. _{H 2 NC 3 H 6 (CH} 3) Si (OC 2 H 5) 2, H 2 NC 3 H 6 Si (OC 2 H 5) 3, H 2 NC 2 H 4 NHC 3 H 6 (CH 3) Si ( OCH ₃ ) ₂ , H ₂ NC ₂ H ₄ NHC ₃ H ₆ Si (OCH ₃ )
₃ , (CH ₃ ) HNC ₃ H ₆ Si (OC ₃ H ₇ ) ₃ , (C ₁₂ H ₂₅ ) HNC ₂ H ₄ NHC ₃ H ₆ Si (OC
H ₃ ) ₃ , C ₆ H ₅ CH ₂ (CH ₃ ) NC ₄ H ₈ NHC ₄ H ₈ (CH ₃ ) Si (OCH ₃ ) ₂ , H ₂ NC ₂ H ₄ NHC ₂ H ₄ NHC ₃ H ₆ Si ( OC ₂ H ₅ ) ₃ As the dicarboxylic anhydride for reacting with the aminoalkoxysilane, for example, phthalic anhydride, succinic anhydride, methyl succinic anhydride, maleic anhydride,
Examples thereof include glutaric anhydride and itaconic anhydride.

The component (D) can be easily obtained by mixing at room temperature for 1 to 5 hours in a parent solvent for both of the above starting materials, for example, alcohol. In this case, since it is necessary that at least one amide group and carboxy group be contained in one molecule of the reaction product, the NH group present in one molecule of aminoalkoxysilane or a partial hydrolysis condensate thereof is used. At least one for one
It is necessary to react the molecular dicarboxylic anhydride. The amount of the component (D) is 0.1 to 20 parts by weight based on 100 parts by weight of the component (A). If the amount is less than 0.1 part by weight, there is no effect of improving the adhesiveness to the substrate, and the amount exceeds 20 parts by weight. And the flexibility is reduced. Preferably, it is 0.5 to 10 parts by weight.

Next, the epoxysilane or amino group-containing alkoxysilane and / or its partially hydrolyzed condensate, which is the component (E), is a component for improving flexibility and adhesiveness. Is done. γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane,
N-cyclohexyl-γ-aminopropyltrimethoxysilane, γ-morpholinopropylmethyldimethoxysilane. The amount of the component (E) is 0.1 to 20 parts by weight based on 100 parts by weight of the component (A). If the amount is less than 0.1 part by weight, there is no effect on the improvement of flexibility and adhesiveness. ,
Conversely, since the degree of crosslinking is too high, the silicone rubber film becomes hard and the flexibility is reduced. Preferably, it is 0.5 to 10 parts by weight.

Next, the curing catalyst of the component (F) is blended for crosslinking and curing the components of the composition of the present invention. Specifically, for example, dibutyltin dilaurate, dibutyltin dioctate, dioctyl Examples thereof include organic acid metal salts such as tin dilaurate, dioctyltin diacetate, tin octylate, zinc stearate, zinc octylate, zinc acetate, and iron octylate; and amine compounds such as n-hexylamine and guanidine. Except when these curing catalysts are water-soluble, it is desirable to prepare them in the form of emulsions previously emulsified and dispersed in water using a surfactant. The amount of the component (F) is 0.01 to 10 parts by weight based on 100 parts by weight of the component (A). If the amount is less than 0.01 part by weight, the composition of the present invention cannot be sufficiently cured. If the strength of the film is reduced and exceeds 10 parts by weight, the catalyst components remaining in the film as non-volatile components inhibit the film characteristics. Preferably, it is 0.1 to 5 parts by weight.

The surfactant used to form the above components into an emulsion is not particularly limited. Examples thereof include alkyl sulfates, alkylbenzene sulfonates, and the like.
Anionic surfactants such as alkyl phosphates, nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene fatty acid esters, sorbitan fatty acid esters, quaternary ammonium salts, alkylamine acetic acid Examples thereof include cationic surfactants such as salts and amphoteric surfactants such as alkyl betaines and alkyl imidazolines.

The composition of the present invention may contain other components, such as thickeners, defoamers, pigments, inorganic powders, penetrants, antistatics, which are usually added to water-based paints or fiber treatment agents as necessary. An antiseptic, a preservative and the like can be appropriately blended. There is no particular limitation on the method of treating the composition of the present invention, and brushing, roll coating, spray coating, knife coating,
It can be performed by a known method such as dip coating. Thereafter, the film is cured by drying at room temperature to form a rubber film. Heating as required to accelerate the curing is effective in shortening the processing time. The composition of the present invention can be widely applied as a paint, a fiber treatment agent, a release agent, a back surface treatment agent for an adhesive sheet, a binder of an inorganic or organic substance, and the like.

[0021]

【Example】

<Preparation of Component (A)> 500 g of octamethylcyclotetrasiloxane, 5.4 g of phenyltriethoxysilane, and 100 g of a 10% aqueous solution of dodecylbenzenesulfonic acid were charged into a 2-liter polyethylene beaker, mixed uniformly with a homomixer, and mixed with 394.6 water. g gradually added to and emulsified and dispersed in water and then, under a pressure 300 kg / cm ² into a high pressure homogenizer 2
Passed through to obtain a stable emulsion. This emulsion was transferred to a 2 liter glass flask equipped with a stirrer, thermometer, and reflux condenser. The polymerization reaction was carried out at 50 ° C. for 24 hours, and then aged at 25 ° C. for 24 hours. This was added to obtain "Emulsion A". This emulsion had a non-volatile content of 45.5% after drying at 105 ° C for 3 hours.
The organopolysiloxane in the emulsion is GPC,
When the instrumental analysis such as IR and NMR was performed, it was represented by the following average formula.

Embedded image

<Preparation of Component (B)> Stirrer, thermometer,
A 1-liter glass flask equipped with a reflux condenser was charged with 600 g of tetramethylcyclotetrasiloxane, 32.4 g of hexamethyldisiloxane, and 12.6 g of sulfuric acid, and allowed to undergo an equilibration reaction at room temperature for 12 hours. Summed up. The obtained organopolysiloxane is GPC,
When the instrumental analysis such as IR and NMR was performed, it was represented by the following average formula.

Embedded image

300 g of the obtained organopolysiloxane and 50 g of polyoxyethylene nonylphenyl ether (10 mol of EO adduct) were charged into a 2-liter polyethylene beaker, uniformly mixed with a homomixer, and 650 g of water was gradually added thereto to add water. Emulsified and dispersed at a pressure of 300 kg / cm ²
And passed twice through a high-pressure homogenizer to obtain a stable "emulsion B".

<Preparation of (D) component> A stirrer, a thermometer,
A 1-liter glass flask equipped with a reflux condenser and a dropping funnel was charged with 98 g of maleic anhydride and 319 g of ethanol, and after uniformly dissolving, 221 g of γ-aminopropyltriethoxysilane was added dropwise at room temperature for 1 hour. After completion of the dropwise addition, stirring was further continued for 1 hour to carry out a reaction, and a pale yellow transparent "solution D" was obtained. This solution had a nonvolatile content of 48.5% after drying at 105 ° C. for 3 hours, and the reaction product in the solution was GP
When instrumental analysis such as C, IR and NMR was performed, it was represented by the following formula. HOOCCH = CHCONHC ₃ H ₆ Si (OC ₂ H ₅ ) ₃

<Preparation of Component (F)> 300 g of dioctyltin dilaurate and 50 g of polyoxyethylene nonyl phenyl ether (10 mol of EO adduct) were charged into a 2-liter polyethylene beaker, mixed uniformly with a homomixer, and 650 g of water was added. Add slowly and emulsify and disperse in water, then pass twice through a high-pressure homogenizer at a pressure of 300 kg / cm ² ,
A stable "emulsion F" was obtained.

<Preparation of Composition> At the compounding amount shown in Table 1, first, the component (D) was added to colloidal silica (Snowtex C manufactured by Nissan Chemical Co., active ingredient 20%) as the component (C) under stirring. After adding “Solution D” and then adding γ-glycidoxypropyltrimethoxysilane as the component (E), stirring was further continued for 30 minutes to obtain a uniform dispersion. Subsequently, the obtained dispersion liquid is gradually added to “Emulsion A” as the component (A) under stirring, and then “Emulsion F” as the component (F) and “Emulsion B” as the component (B). Was added to prepare a composition.

<Evaluation of Physical Properties of Film and Adhesion to Various Substrates> The above composition was poured into a casting plate made of a fluororesin and left for 48 hours in an atmosphere at a temperature of 25 ° C. and a relative humidity of 60% to a thickness of about 1 mm. A cured film of was prepared. The hardness, tensile strength and elongation of this film were measured according to JIS K630.
It measured according to 1. In addition, similarly, a cured film was prepared using a casting plate composed of various substrates as shown in Table 1, and one end of the film was formed in a direction perpendicular to the substrate by about 300 mm /
The film was pulled at a speed of one minute, and the state of the film and the substrate at this time was observed and evaluated as follows. ：: The adhesiveness was extremely excellent, and the film was broken without peeling off at the interface between the film and the substrate. Δ: Peeled off at the interface, but required considerable force. D: Peeled off at the interface, and almost no force was required. Table 1 shows the evaluation results.

<Evaluation of properties as a fiber treatment agent> The composition prepared above was further added with stirring to carboxymethylcellulose (Serogen F, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a thickener.
Was added to prepare a treatment composition having a viscosity of 30,000 centipoise. Then, using a 66-nylon filament yarn having a fineness of 420 denier, the woven fabric was plain woven at a density of 46 / weft yarns / inch, and the treatment composition was about 30 g. After knife coating so as to give a coating amount of / m ² , heat curing was performed at 150 ° C. for 2 minutes to prepare a treated cloth for testing. The following properties were evaluated for the treated cloth. Flexibility: Using a Uenoyama type texture meter, the bending resistance of the treated cloth (15 cm width) was measured. (The smaller the value, the better the flexibility.) ・ Tear strength of the sewn part: Sew 5 mm from the end of the two layers of treated cloth (5 cm wide) with polyester thread and sew each end on the opposite side The portion was pulled, and the strength at which the treated cloth at the sewn portion was torn was measured. (See FIG. 1) Flammability: Evaluated by FMVSS 302 method. Burning speed of 101.2mm / min or less passed Table 2 shows the evaluation results.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

The composition of the present invention is easily cured at room temperature by the removal of water to form a rubber film, and the film has excellent strength, flexibility, and adhesion to various substrates. Is good.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a test piece for measuring a tear strength of a sewn portion and a tensile direction thereof. (A) Explanatory drawing which shows the outline | summary of a test piece, (b) Explanatory drawing which shows the tensile direction of a test piece.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI // C09D 183/04 C09D 183/04 (72) Inventor Morizomi Nakazato 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture 10 Shin-Etsu Chemical Yoshito Osawa, Inventor, Silicone Electronic Materials Technology Laboratories, Inc. 1-10, Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture, Japan Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (72) Inventor, Sachiko Nezu Gunma 1-10 Hitomi, Matsuida-machi, Usui-gun, Japan Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (72) Inventor Takeshi Ken Fukuda 2-6-1 Otemachi, Chiyoda-ku, Tokyo Shin-Etsu Chemical Co., Ltd. 56) references Patent flat 2-233763 (JP, a) JP flat 5-93135 (JP, a) (58 ) investigated the field (Int.Cl. ^7, D Name) C08L 83/04 - 83/08 C08K 3/36 C08K 5/54

Claims (1)

(57) [Claims] (A) General formula (A) [Wherein, R ¹ is the same or different, unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, Z is R ¹ , OR ² or (OSiR ¹ R ¹ ) _k OR ²
R ² is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, k is 0 to 1,00
X represents an identical or different group represented by R ¹ or OR ² ; m represents an integer of 100 to 10,000; n represents an integer of 0 to 1,000]; 100 parts by weight of an organopolysiloxane containing an OR ² group, (B) a hydroxy group and / or an alkoxy group in the organopolysiloxane containing at least two Si—H bonds in one molecule, When two groups are present in one molecule, 0.5 to 50 parts by weight of an organopolysiloxane containing at least three Si-H bonds in one molecule, (C) 0.5 to 100 parts by weight of colloidal silica , (D ) Amido- and carboxyl-containing organoalkoxysilanes and / or partial hydrolysis condensates thereof 0.1 to 20 parts by weight, (E) Epoxy or amino group-containing organoalkoxysilanes and / or partial hydrolysis condensates 0.1 to 20 parts by weight 20 parts by weight, (F Silicone aqueous emulsion composition comprising a curing catalyst 0.01 to 10 parts by weight as the main component.