JP2002038015A - Organopolysiloxane emulsion composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organopolysiloxane emulsion composition which is easily cured and is excellent in strength, elongation, adhesion properties to various basic materials, or the like, and besides is improved in slip properties on a coating surface, when shearing force is loaded, a contact material easily results in a slidable cured product. SOLUTION: The organopolysiloxane emulsion composition comprises (A) 100 pts.wt. of an organopolysiloxane having at least two hydroxy groups and/or alkoxy groups bonded to a silicon atom in a molecule, (B) 0.5-100 pts.wt. of silica and/or polysilsesquioxane, (C) 0.1-20 pts.wt. of a reaction product of an amino group-containing alkoxysilane and/or its partial hydrolyzate with an acid anhydride, (D) 0.1-20 pts.wt. of an epoxy group-containing alkoxysilane and/or its partial hydrolytic condenzate, (E) 10-1,000 pts.wt. of a powder unreactive with the components (A), (B), (C), and (D), and (F) 0.01-10 pts.wt. of a catalyst for curing, as principal components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organopolysiloxane emulsion composition which cures to form a rubber film, and can be used not only as a release agent, a back surface treatment agent for an adhesive sheet, a paint, etc. The present invention relates to an organopolysiloxane emulsion composition capable of forming a rubber film for preventing damage to a contact surface when an article is brought into contact.

[0002]

2. Description of the Related Art Conventionally, organopolysiloxane emulsion compositions which cure to form a rubber film have been known, and it is also known that such compositions consist of various compositions. For example, silicone emulsion compositions comprising an anionically stabilized hydroxylated diorganopolysiloxane, colloidal silica, an organotin compound or an organic amine compound and having a pH in the range of 9 to 11.5 have been proposed ( JP-A-56-16553). However, since this composition has poor adhesion to various substrates and is highly alkaline, it has a drawback that various restrictions are imposed on its use.

Further, in order to improve the adhesiveness of such a composition, for example, it comprises a hydroxyl group-containing organopolysiloxane emulsion, a reaction product of an aminofunctional silane and an acid anhydride, colloidal silica and a curing catalyst. Silicone aqueous emulsion compositions (see JP-A-58-101153), organopolysiloxanes having two or more alkoxy groups or hydroxyl groups bonded to silicon atoms in one molecule, two or more Si-
H-bonded organopolysiloxane, silica and / or
Alternatively, a silicone aqueous emulsion composition comprising a polysilsesquioxane, an organoalkoxysilane containing an amide group and a carboxyl group, an organoalkoxysilane containing an epoxy group or an amino group, and a curing catalyst (Japanese Patent Laid-Open No.
-85760), a film-forming silicone emulsion, an ureido group-containing organoalkoxysilane or an emulsion-type silicone composition comprising a partially hydrolyzed condensate thereof (see JP-A-10-204294), and a hydroxyl group or an alkoxy group. Organopolysiloxanes Contained in Chains and Terminals (JP-A-11-15838)
No. 0), and an aqueous silicone emulsion composition comprising finely divided silica and a curing accelerator have been proposed.

However, in each of these cases,
Although improvements in adhesion or film strength with the base material are observed, the slipperiness between the applied surface and the contacted object when another article is brought into contact with the applied surface is insufficient, When a strong shearing force is applied to the contact object, there is a disadvantage that the coating film or the substrate or the contact object itself is broken.

On the other hand, it is already known to add various fillers to an organopolysiloxane emulsion composition which cures to form a rubber film. However, its purpose is to use it as a colorant or an ultraviolet shielding agent, or to increase the solid content as an extender to make a thick coating type coating material or sealing material (JP-A-56-165).
No. 53, JP-A-58-118853 and JP-A-61-246255). In each case, not only the film properties such as strength and elongation but also the adhesiveness to the base material and the like are unsatisfactory. Was enough. Also, as an effect of its addition,
No mention is made as to whether the slipperiness of the coating film surface is improved.

[0006]

Accordingly, an object of the present invention is to cure easily at room temperature, to have excellent strength, elongation, excellent adhesion to various substrates, etc., to improve the slipperiness of the coated surface, and to reduce the shearing force. An object of the present invention is to provide an organopolysiloxane emulsion composition in which a contact product becomes a cured product that can be easily slid when it is applied.

[0007]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
(A) an organopolysiloxane containing at least two hydroxy groups and / or alkoxy groups bonded to a silicon atom in one molecule: 100 parts by weight, (B) silica and / or
Or polysilsesquioxane: 0.5 to 100 parts by weight,
(C) a reaction product of an amino group-containing alkoxysilane and / or a partial hydrolyzate thereof with an acid anhydride: 0.1 to 20
Parts by weight, (D) epoxy group-containing alkoxysilane and / or
Or its partial hydrolysis condensate: 0.1 to 20 parts by weight,
(E) a solid powder that is non-reactive with the above components (A), (B), (C) and (D): 10 to 1,000 parts by weight;
(F) Curing catalyst: achieved by an organopolysiloxane emulsion composition containing 0.01 to 10 parts by weight as a main component.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The organopolysiloxane as the component (A) in the present invention only needs to contain at least two hydroxy groups and / or alkoxy groups bonded to silicon atoms in one molecule. There are no particular restrictions on the bonding position of the group, the type of organic group other than the hydroxy group and the alkoxy group bonded to the silicon atom, the molecular structure, the degree of polymerization, and the like, and various conventionally known ones can be used. .

Such an organopolysiloxane can be produced by a conventionally known method, for example, a method of subjecting a cyclic siloxane such as octamethyltetracyclosiloxane to ring-opening polymerization,
It can be synthesized by a method of hydrolytic condensation polymerization of an organohalosilane, an organoalkoxysilane or the like. These organopolysiloxanes are desirably used in the form of an emulsion emulsified and dispersed in water using a surfactant. Therefore, the organopolysiloxane of the present invention is prepared by an emulsion polymerization method, that is, a method in which a cyclic siloxane and, if necessary, an organoalkoxysilane are further emulsified and dispersed in water using a surfactant, and then an acid is added, if necessary. Alternatively, it is preferable to synthesize in the form of an emulsion by adding a catalyst such as an alkali to cause a polymerization reaction.

[0010] Silica and / or polysilsesquioxane as the component (B) is a reinforcing component for improving the strength of the silicone rubber film by reacting with the organopolysiloxane as the component (A). In the present invention, it is particularly preferable to use colloidal silica or to use an emulsion emulsified and dispersed in water using a surfactant.
Such an emulsion may be prepared by mixing the component (B) silica and / or polysilsesquioxane with the component (A) organopolysiloxane and then emulsifying and dispersing the mixture in water using a surfactant. It can be prepared by emulsifying and dispersing an organoalkoxysilane in water using a surfactant, and then, if necessary, adding a catalyst such as an acid or an alkali to carry out hydrolytic condensation polymerization. Component (B) is added in an amount of 0.5 to 100 parts by weight, preferably 1 to 5 parts by weight, per 100 parts by weight of component (A).
0 parts by weight. If the amount is less than 0.5 part by weight, there is no effect of improving the strength of the silicone rubber film, and if it exceeds 100 parts by weight, the film becomes hard and brittle, and the strength is reduced.

The reaction product of the amino group-containing organoalkoxysilane and / or its partial hydrolyzate and the acid anhydride as the component (C) is a component for improving the adhesiveness between the silicone rubber film and the substrate. It is. Examples of the amino group-containing alkoxysilane as the starting material include, for example, γ
-Aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, N-β (aminoethyl)
γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-methyl-γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, etc. Can be. Further, these partial hydrolysates or mixtures thereof can also be used. Examples of the acid anhydride as the other starting material include phthalic anhydride, succinic anhydride, maleic anhydride, glutaric anhydride, and itaconic anhydride.

The reaction of the above-mentioned amino group-containing organoalkoxysilane and / or a partial hydrolyzate thereof with an acid anhydride is carried out at room temperature in a parent solvent for both starting materials, for example, an alcohol such as methanol, ethanol or isopropanol. It can be easily performed by stirring for 1 to 5 hours. Further, it is preferable that their reaction molar ratios are equimolar, but there is no problem if either one is used in excess. The amount of the component (C) is (A)
0.1 to 20 parts by weight per 100 parts by weight of the component,
Preferably it is 0.5 to 10 parts by weight. If the amount is less than 0.1 part by weight, there is no effect of improving the adhesiveness to the substrate, and if it exceeds 20 parts by weight, the stability of the composition decreases.

The epoxy group-containing alkoxysilane (D) and / or its partially hydrolyzed condensate are (A)
To improve the film strength as a crosslinking agent for the organopolysiloxane as a component and to use it together with a reaction product of an amino group-containing organoalkoxysilane and / or a partial hydrolyzate thereof and an acid anhydride as a component (C). By
It is a component for improving the adhesion to the base material. The component (D) includes, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, and the like. Hydrolysis condensates or mixtures thereof can be mentioned.

The amount of the component (D) is 100 parts.
The amount is 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight based on parts by weight. If the amount is less than 0.1 part by weight, the degree of cross-linking becomes insufficient, so that the film strength cannot be improved and there is no effect of improving the adhesiveness to the base material,
If the amount is more than 10 parts by weight, the degree of crosslinking is too high, and the silicone rubber film becomes brittle.

The components (E), (A), (B),
The powder that is non-reactive with each of the components (C) and (D) is a component for improving the slipperiness of the silicone rubber film surface. Therefore, this powder must be non-reactive with each of the above components and independently movable on the film surface. As such a powder, for example, a powder of a metal oxide such as titanium oxide, zinc oxide, and aluminum oxide, and a reaction of a contained hydroxyl group with hexamethyldisilazane or the like to obtain (A)
Examples thereof include silica, silicone resin powder, and the like, and organic plastic powders such as polyester and nylon, which are made nonreactive with each component such as (B), (C), and (D). When a large load is applied to the application surface,
From the viewpoint of hardness, it is particularly desirable to use inorganic metal oxide powder.

These powders may be used simply by mixing them. However, after mixing with the organopolysiloxane of the component (A), the mixture is used in the form of an emulsion emulsified and dispersed in water using a surfactant. Is preferred. The amount of the component (E) is from 10 to 1.0 based on 100 parts by weight of the component (A).
00 parts by weight, preferably 50 to 500 parts by weight. When the amount is less than 10 parts by weight, there is no effect of improving the slipperiness of the silicone rubber film surface, and when the amount exceeds 1,000 parts by weight, the strength, elongation, adhesiveness to the base material and the like of the silicone rubber film are reduced.

The curing catalyst as the component (F) is used to crosslink and cure the components (A), (B), (C) and (D). Organic acid metal salts such as tin dilaurate, dioctyltin dilaurate, dioctyltin diacetate, tin octylate, zinc acetate, zinc octylate, zinc stearate, and iron octylate; amine compounds such as n-hexylamine and guanidine; be able to. It is desirable that these curing catalysts are in the form of an emulsion which is emulsified and dispersed in water using a surfactant in advance, unless the catalyst is water-soluble.

The compounding amount of the component (F) is as follows:
The amount is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, per 100 parts by weight. If the amount is less than 0.01 part by weight, the components (A), (B), (C) and (D) cannot be sufficiently cured, and the strength of the silicone rubber film decreases. Further, even when used in an amount exceeding 10 parts by weight, no further effect on the curing reaction is recognized, and cracks are easily generated in the obtained silicone rubber film.

The surfactant used to form the above components into an emulsion is not particularly limited.
For example, anionic surfactants such as alkyl sulfate, alkyl benzene sulfonate, alkyl phosphate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfonate; polyoxyethylene alkyl ether, polyoxyethylene Nonionic surfactants such as alkyl phenyl ethers, polyoxyethylene fatty acid esters, polyhydric alcohol fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and sucrose fatty acid esters; alkylamine acetates, polyamines and amino alcohol fatty acid derivatives Such as amine salts, alkyl quaternary ammonium salts, aromatic quaternary ammonium salts, pyridinium salts, imidazolium salts and the like; May be mentioned amphoteric surfactants kill imidazoline, and the like.

The composition of the present invention may contain, if necessary, other components which are usually added to an aqueous paint or the like, for example, a thickener,
An antifoaming agent, a pigment, an antistatic agent, a preservative, and the like may be appropriately blended. The method of treating the substrate with the composition of the present invention is not particularly limited, and the composition can be applied by brush coating, roll coating, knife coating, spraying, dipping, or the like. After the application, the coating is cured by drying at room temperature to form a rubber film. However, if necessary, the coating can be heated to accelerate the curing and shorten the processing time.
The composition of the present invention is a release agent, a back surface treatment agent for an adhesive sheet,
It can be widely applied as paints and the like.

[0021]

The composition of the present invention is easily cured by removing water by drying after coating, and the cured film not only has excellent strength and elongation, but also can be applied to various substrates when applied. In addition to being excellent in adhesiveness, the sliding surface of the application surface is good, and even if a shear force is applied while another substrate is in contact with the application surface of the substrate, the contact object can slide. In addition, the coating film, the substrate, and the other substrate (contact object) brought into contact with the application surface are not damaged.

[0022]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples.
As will be described, the present invention is limited by these.
There is no.Preparation of (A) component  A-1: In a 2 liter polyethylene beaker,
500 g of an organopolysilixane represented by an average formula and
Polyoxyethylene lauryl ether (ethylene oxa
(9 mol adduct) and 50 g with a homomixer.
Mixed together.450 g of water is gradually added to the obtained mixture and emulsified in water.
Disperse, then high pressure homogenizer at a pressure of 30 MPa
The emulsion was passed twice through the flask to obtain "Emulsion A-1".

A-2: A 2-liter polyethylene beaker was charged with octamethylcyclotetrasiloxane 500.
g, 5.4 g of phenyltriethoxysilane and 100 g of a 10% by weight aqueous solution of dodecylbenzenesulfonic acid, and the mixture was stirred with a homomixer to emulsify.
4.6 g was added for dilution. Then, the mixture was passed twice through a high-pressure homogenizer at a pressure of 30 MPa to emulsify. The obtained emulsion was transferred to a 2 liter glass flask equipped with a stirrer, a thermometer and a reflux condenser, and allowed to undergo a polymerization reaction at 50 ° C. for 48 hours, followed by aging at 25 ° C. for 24 hours. The emulsion was neutralized with a weight% aqueous sodium carbonate solution to obtain "Emulsion A-2".

The nonvolatile content of this emulsion was 46.3% by weight (after drying at 105 ° C. for 3 hours). For the organopolysiloxane in the emulsion, GPC, I
As a result of performing instrumental analysis such as R and NMR, it was found that the organopolysiloxane in the emulsion A-2 was represented by the following average formula.

[0025]Preparation of component (C)  1 with stirrer, thermometer, reflux condenser and dropping funnel
In a liter glass flask, add maleic anhydride 98
g and 319 g of ethanol were charged and uniformly dissolved.
Thereafter, 221 g of γ-aminopropyltriethoxysilane was added.
It was added dropwise over 1 hour at room temperature. 1 hour after dropping
The stirring is continued to complete the reaction.
C ". The nonvolatile content of this solution was 48.5% by weight (1
05 ° C / 3 hours after drying). Reaction products in solution
Was analyzed by GPC, IR, NMR, etc.
As a result, the non-volatile content in the solution C is represented by the following formula.
Turned out to be.

[0026]Preparation of component (F)  300 g of dioctyltin dilaurate and polyoxyethyl
Renlauryl ether (addition of 9 mol of ethylene oxide
Material) into a 2 liter polyethylene beaker.
After mixing uniformly with a homomixer, 650 g of water was added.
Add slowly and emulsify and disperse in water, then 30MPa
Pass the emulsion through a high pressure homogenizer twice under pressure.
F "was obtained.

Examples 1 to 6 and Comparative Examples 1 to 6.Preparation of the composition  At the compounding amounts shown in Tables 1 and 2, first, as component (B),
Roydal silica (a snow cover manufactured by Nissan Chemical Industries, Ltd.)
Mix C (trade name), active ingredient 20% by weight) under stirring
Add "solution C" as the component (C), and then add the component (D)
Γ-glycidoxypropyltrimethoxysilane as
After the addition, stirring is continued for another 30 minutes to obtain a uniform dispersion.
Obtained.

[Table 1]

[0028]

[Table 2]

Next, the obtained dispersion is gradually added to the “emulsion A-1” or the “emulsion A-2” as the component (A) with stirring. Aqueous dispersion (Sandyo Super White U (trade name) manufactured by Sanyo Pigment Co., Ltd., active ingredient 65)
% By weight) and “Emulsion F” as a component (F), and carboxymethylcellulose (Serogen F (trade name) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a thickener was added. s was prepared.

[0030]Evaluation of film properties and adhesion to various substrates  Pour the above composition into a fluoroplastic casting plate
And left for 1 week in an atmosphere with a temperature of 25 ° C and a relative humidity of 50%
To form a cured film with a thickness of about 1 mm.
Measures tensile strength and elongation according to JIS K6301
did. Moreover, it consists of various base materials as shown in said Table 1.
Using a casting plate to form a cured film in the same way
And pull one end of the coating perpendicular to the substrate.
The adhesion observed by observing the state of the film and the substrate was as follows:
Was evaluated. The results are as shown in Tables 1 and 2. ：: Sufficient adhesion, peeled off at interface between film and substrate
No, the film was broken. Δ: peels off at the interface between the film and the substrate, but considerable force is required.
It was important. ×: Peeled at the boundary between the membrane and the substrate, requiring almost no force
there were.

[0031]Evaluation of slipperiness of coating surface  Glass each of the above compositions with a knife coat applicator
After applying to the board, heat at 105 ℃ for 30 minutes, the thickness is about
A cured film of 100 μm was obtained. Sliding property of the coated surface
Of urethane foam resin and concrete as contact
Using a square timber, TR type friction measuring machine of Toyo Seiki Seisaku-sho, Ltd.
15cm using²300g load with contact area of
And measure the frictional force at a pulling speed of 15 cm / min.
Was. The results are as shown in Tables 1 and 2.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 67/00 C08L 67/00 77/00 77/00 83/04 83/04 83/08 83/08 ( 72) Inventor Ken Fukuda 2-6-1 Otemachi, Chiyoda-ku, Tokyo F-term in Shin-Etsu Chemical Co., Ltd. FD148 FD150 FD310 GH01 HA07

Claims (1)

[Claims] 1. (A) 100 parts by weight of an organopolysiloxane containing at least two hydroxy groups and / or alkoxy groups bonded to a silicon atom in one molecule;
(B) Silica and / or polysilsesquioxane ... 0.
5 to 100 parts by weight, (C) a reaction product of an amino group-containing alkoxysilane and / or a partial hydrolyzate thereof and an acid anhydride 0.1 to 20 parts by weight, (D) an epoxy group-containing alkoxysilane and / or Or a partial hydrolysis condensate thereof.
1 to 20 parts by weight, (E) above (A), (B), (C),
An organopolysiloxane emulsion composition comprising, as main components, a powder which is non-reactive with the component (D): 10 to 1,000 parts by weight, and (F) a curing catalyst: 0.01 to 10 parts by weight.