JP2001172566A - Primer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a primer composition having an excellent weather resistance, heat resistance and water resistance which may be widely applicable to various adherends with different surface structures. SOLUTION: The primer composition contains a polysiloxane compound which possesses a hydrolyzable silyl group, a polyisobutylene structure and a siloxane bond and has a polymerization degree of >=20 and an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a primer composition having excellent weather resistance, heat resistance and water resistance, which can be widely applied to various adherends having various surface morphologies.

[0002]

2. Description of the Related Art Organic polymers, such as polyisobutylene, having a saturated hydrocarbon as a skeleton and having a reactive functional group, are characterized by their excellent weather resistance, heat resistance, and water resistance. It is suitably used for sealants and the like.

However, since the saturated hydrocarbon polymer is non-polar, it has a problem in adhesiveness, and the use of a primer is essential. As the primer, JP-A-11-20970
No. 1, JP-A-11-209702, a method using a saturated hydrocarbon polymer as a binder component, and JP-A-4-252283, a method using an epoxy resin. The publication discloses a method using an additive such as silica.

Further, Japanese Patent Publication No. 6-6680 proposes a primer containing a reactive silicone resin and a specific amino group-containing alkoxysilane with the aim of improving the adhesion to silicones and the like. Japanese Patent Application Laid-Open No. 9-
Japanese Patent No. 95656 proposes a primer containing a specific silicon compound for the purpose of improving the adhesiveness to a coating film surface with an acrylic electrodeposition paint or a fluororesin paint, but various primers having various surface morphologies are proposed. There is no example of a primer which can be applied comprehensively to all of the body.

On the other hand, in order to effectively utilize the excellent properties of silicone as a resin composition, such as heat resistance, oxidation resistance, weather resistance, and adhesion, vinyl resins such as glycols, acrylics, and styrenes are used. Attempts have been made to impart various properties by graft polymerization of a system polymer component.

For example, JP-A-10-36460 discloses an invention in which a monomer having an ethylenically unsaturated bond is graft-polymerized on silicone.
JP-A-279031 discloses a method of graft-polymerizing an oxyalkylene group-containing organic compound onto a silicon-bonded hydrogen atom-containing silicone. In addition, Japanese Patent Laid-Open No. 7-1
No. 8036 discloses an iodine-containing silicone polymer,
A silicone graft copolymer for graft polymerizing a radically polymerizable monomer is disclosed.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a primer having good adhesion to all kinds of adherends having various different surface morphologies and capable of forming a uniform coating film. In addition, to provide a primer composition having good adhesion to a cured composition mainly composed of a nonpolar saturated hydrocarbon-based organic polymer having excellent weather resistance, heat resistance, and water resistance. is there.

The present inventors have applied, as a primer, a graft copolymer capable of imparting various properties to silicone having excellent properties as described above by graft polymerization,
As a result of intensive studies to obtain a primer composition having high applicability, the inventors have found that a silicone graft copolymer obtained by adding polyisobutylene to silicone has excellent properties as a main agent of a primer, and completed the present invention. .

[0009]

That is, the present invention provides a primer composition comprising a polymer having a degree of polymerization of 20 or more and having a hydrolyzable silyl group, a polyisobutylene structure and a siloxane bond, and an organic solvent. Offer things. Further, it contains a polysiloxane compound (A) having a siloxane structure represented by the following formula (1) and / or a polysiloxane compound (B) having a siloxane structure represented by the following formula (2) and an organic solvent. A primer composition is provided.

[0010]

Embedded image

In the formula, X is polyisobutylene optionally having a terminal silyl group, and Y is an alkyl group having 1 to 18 carbon atoms optionally having a terminal silyl group. Also,
Z is a hydrolyzable group. a, b, c, d, and e are integers, and a / a + b = 0.01 to 0.9 and b / a + b =
0.01-0.7, c / c + d + e = 0.01-0.
7, d / c + d + e = 0.01 to 0.9, and e / c
+ D + e = 0.01 to 0.9, and d and e may each independently be 0.

Further, the present invention provides the above-mentioned primer composition,
Further, the present invention provides a primer composition containing a polyisobutylene compound having a silyl group at a terminal. The present invention also provides a primer composition, wherein the primer composition further contains a silanol condensation catalyst and / or a silane coupling agent.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below. The primer composition of the present invention contains a polymer having a hydrolyzable silyl group, a polyisobutylene structure and a siloxane bond and having a degree of polymerization of 20 or more, and an organic solvent. The polymer may be one kind or two or more kinds. The hydrolyzable silyl group or polyisobutylene structure may be present on the side chain of the polysiloxane compound,
When the polysiloxane compound does not have any of these, a compound containing either or both of them may be added to mix the two in the primer composition.

When the polysiloxane compound has a hydrolyzable silyl group or a polyisobutylene structure in the side chain,
A polysiloxane compound having both of these at the same time can be used. In this case, the degree of polymerization of the polysiloxane compound is 20 or more. Further, each of the polysiloxane compounds having one of them in the side chain may be contained in the composition. In this case, the degree of polymerization of each polysiloxane compound is 20 or more in total. Further, by containing a polysiloxane compound having one of them in a side chain and having a degree of polymerization of 20 or more, and a compound having a hydrolyzable silyl group or / and a polyisobutylene structure, both components are contained in the composition. May be mixed.

1. Polysiloxane Compound The polysiloxane compound is preferably a polysiloxane compound (A) having a siloxane structure represented by the following formula (1) or a polysiloxane compound (B) having a siloxane structure represented by the following formula (2): ) Or both.

[0016]

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Polysiloxane Compound (A) The polysiloxane compound (A) has a structure represented by the above formula (1). In the formula (1), X is polyisobutylene, and a silyl group is added to the terminal. May have. The silyl group is preferably a group represented by the following formula (3).

[0018]

Embedded image

In the formula (3), Rs may be the same or different and represent a hydrolyzable group or an alkyl group, at least one of which is a hydrolyzable group. As the hydrolyzable group, specifically, a hydrogen atom, an alkoxy group,
Preferred examples include an acyloxy group, a ketoximate group, an amino group, an amide group, an aminooxy group, a mercapto group, and an alkenyloxy group. Among them, an alkoxy group is preferable in terms of mild hydrolytic property and easy handling, and a methoxy group and an ethoxy group are particularly preferable. The alkyl group preferably has 1 to 18 carbon atoms, and particularly preferably a methyl group and an ethyl group.

Accordingly, X is preferably monovalent polyisobutylene having a number average molecular weight of 300 to 30,000, which may have trimethoxysilane, triethoxysilane, or methyldimethoxysilane at its terminals.

The arrangement of each siloxane structure in the molecule is not particularly limited, and the degree of polymerization of the siloxane structure is 20 or more.
These are included in the following composition ratios. That is, a and b in the formula are integers, preferably a is 1 to 200, b is 1 to 200, and more preferably a is 1
50, b is 1 to 50, and a / a + b = 0.01 to
0.9, b / a + b = 0.01 to 0.7. Within this range, the compatibility of the composition of the present invention used as a primer is good, and the adhesiveness of polyisobutylene, aging resistance, ozone resistance, gas impermeability, various excellent properties such as heat resistance, etc. Characteristics can be sufficiently imparted.

Polysiloxane Compound (B) The polysiloxane compound (B) has a structure represented by the above formula (2), and X in the formula (2) represents the above formula (1)
It is synonymous with X in. Y is an alkyl group having 1 to 18 carbon atoms which may have a silyl group at the terminal. The silyl group is preferably a compound represented by the above formula (3). When Y has a hydrolyzable group-containing silyl group represented by the above formula (3), the adhesion of the primer composition of the present invention containing the polysiloxane compound (B) to an adherend is improved. It is. As Y, specifically, monovalent trimethoxyethylsilane or monovalent triethoxyethylsilane is preferably exemplified.

Z is a hydrolyzable group. The primer composition of the present invention containing the polysiloxane compound (B) comprises:
By having Z in the side chain, the adhesiveness to the adherend is improved. The hydrolyzable group is not particularly limited,
Specifically, a hydrogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an aminooxy group, a mercapto group, an alkenyloxy group and the like are preferably exemplified. In particular, an alkoxy group is preferable because it has mild hydrolyzability and is easy to handle. The alkoxy group preferably has 1 to 3 carbon atoms, and includes a methoxy group, an ethoxy group, an n-propyloxy group, and an isopropyloxy group.

In addition, ether compounds having a hydroxyl group such as monovalent ethylene glycol monomethyl ether and monovalent diethylene glycol monomethyl ether can be exemplified, and monovalent ethylene glycol monomethyl ether is particularly preferable.

In the polysiloxane compound (B),
The arrangement of each siloxane structure in the molecule is not particularly limited, and the degree of polymerization of the siloxane structure is 20 or more. These are included in the following composition ratios. That is, c, d,
e is an integer, preferably, c is 1 to 200, and d is 0
~ 200, e is 0 ~ 200, more preferably c is 1 ~ 5
0 and d are 0 to 100, and e is 0 to 100, and these are c / c + d + e = 0.01 to 0.7, d / c + d +
e = 0.01 to 0.9, e / c + d + e = 0.01 to
0.9 and d and e may each independently be 0. Within this range, the above-mentioned excellent cured product can be obtained as a primer, and the hot water resistance can be further improved.

The above polysiloxane compounds may be used alone or in combination of two or more. The number average molecular weight is preferably about 500 to 100,000.
In particular, those having a liquid or fluidity of about 1,000 to 30,000 are preferable.

Preferred examples of the polysiloxane compound include compounds having the following structures.

[0028]

Embedded image

In the composition of the present invention, the polysiloxane compounds (A) and (B) may be used in combination.
The ratio of (A) :( B) is 0.1: 10 to 10: 0.1
It is preferable that both are uniformly dispersed and not separated in a solvent.

Polysiloxane compounds (A) and (B)
Are synthesized, for example, by reacting a polysiloxane having an Si-H group with a corresponding alcohol or polyisobutylene or an alkyl group having at least one alkenyl group in a molecule under a transition metal catalyst such as chloroplatinic acid. be able to.

[0031] The primer composition of the present invention can be used in addition to a polysiloxane having advantages such as excellent heat resistance, oxidation stability, weather resistance, adhesiveness and chemical inertness which are not found in other materials. By containing a polysiloxane compound that graft-polymerizes polyisobutylene, not only the compatibility with a cured composition containing a saturated hydrocarbon polymer is improved, but also the tackiness of polyisobutylene,
Various excellent properties such as aging resistance, ozone resistance, gas impermeability, heat resistance and the like can be imparted, and can be suitably used as a primer. In particular, such a highly adhesive primer can effectively function even on an adherend having a porous surface form such as mortar, and has high applicability. When a polysiloxane compound having a hydrolyzable group-containing silyl group and a hydrolyzable group is used as the functional group, the adhesiveness to the adherend is further improved, and the primer is more suitable.

2. Organic Solvent The primer composition of the present invention contains an organic solvent in order to uniformly disperse the polysiloxane compound. The organic solvent is not particularly limited as long as it is an organic solvent in which the above-mentioned polysiloxane compound is easily soluble and is inert to the polysiloxane compound.

Specifically, aromatic hydrocarbons such as benzene, xylene and toluene, aliphatic hydrocarbons such as n-hexane, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, methyl acetate, ethyl acetate and butyl acetate Such as esters, diethyl ether, tetrahydrofuran, ethers such as dioxane, dichloromethane,
Examples include halogenated hydrocarbons such as chloroform and 1,2-dichloroethane, and phenols such as phenol and p-cresol. These may be used alone or in combination of two or more. However, it is preferable to use n-hexane, xylene, toluene, or a mixed solution of n-hexane and another solvent having appropriate volatility.

The amount of each component described above is based on 10 parts by weight of the polymer or polysiloxane compound in total.
The amount of the organic solvent in the range of 30 to 500 parts by weight is appropriate. Within this range, the composition is compatible and can be sufficiently uniformly dispersed. In addition, the concentration becomes appropriate.

3. Polyisobutylene compound having a terminal silyl group The primer composition of the present invention may include a polyisobutylene compound having a terminal silyl group, if necessary. By containing an appropriate amount of the above polyisobutylene compound, when the content of the monovalent polyisobutylene group (X), which is a side chain of the polysiloxane compound, is insufficient, the phase to the adhesive or cured composition of the polysiloxane is reduced. The effect of imparting solubility can be compensated for and the choice of compounding increases, so that the adjustment of the primer becomes easy.

The polyisobutylene compound has a silyl group at a terminal, and the silyl group is preferably a compound represented by the above formula (3). The polyisobutylene compound preferably has a number average molecular weight of 300 to 30,000 in terms of solubility and tackiness. Specifically, Kanebuchi Chemical Industry's EPION
(E100S, E103S, E303S, E505S)
(Product name).

The compounding amount of the polyisobutylene compound is 0.1 to 20 parts by weight of the polymer or polysiloxane compound in total with respect to 10 parts by weight.
It is appropriate to mix them in the range of parts by weight.
If the amount is less than 0.1 part by weight, sufficient adhesive strength cannot be obtained and 2
If it exceeds 0 parts by weight, a uniform coating film cannot be formed.

4. Silane coupling agent The primer composition of the present invention, in addition to the components described above,
If necessary, by further containing a silane coupling agent, adhesion to various adherends is improved. As the silane coupling agent used in the present invention, for example, γ-
(2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, aminosilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercapto Propyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ-anilinopropyltrimethoxysilane, vinyltrimethoxysilane, γ-chloro Examples thereof include propylmethyldimethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, and trimethylchlorosilane. In particular, aminosilane, epoxysilane or a reaction product of both is excellent in the effect of improving the adhesion to a wet surface, and is preferably used because it is widely used. These may be used alone or in combination of two or more.

The amount of the silane coupling agent is as follows:
The above polymer or polysiloxane compound is added in a total of 10
The range of 0.1 to 20 parts by weight with respect to parts by weight is appropriate. Within this range, the breaking rate of the sealing material with respect to the adhesion to the wet surface is high.

5. Silanol condensation catalyst The primer composition of the present invention can further contain a silanol condensation catalyst. In the present invention, the silanol condensation catalyst is added particularly for the purpose of functioning as a catalyst for the silane coupling agent, but when the polysiloxane compound contains a silyl group having a hydrolyzable group in a side chain, It can also function as a catalyst and promotes a crosslinking reaction.

As the silanol condensation catalyst, conventionally known ones can be used as long as the object of the present invention is not impaired. For example, tin octylate, tin stearate,
Metal salts of organic carboxylic acids such as iron naphthenate and tin octylate, tetravalent organic tins such as di-n-butyltin-di-laurate, di-n-butyltin-di-laurate, laurylamine, ethanolamine And the like, and amines such as alkyl titanates. These may be used alone or in combination of two or more. In particular, organotin, in terms of storage stability and curability,
Organic titanates are preferred.

The compounding amount of the silanol condensation catalyst is in the range of 0.01 to 10 parts by weight of the silanol condensation catalyst per 10 parts by weight of the polysiloxane compound having a hydrolyzable silyl group and the silane coupling agent in total. It is appropriate to mix with.

The primer composition of the present invention may contain, in addition to the above components, a rust preventive, a plasticizer, a filler, a thickener, an antioxidant, an inorganic pigment, as long as the object of the present invention is not impaired.
Components such as an organic pigment, an ultraviolet absorber, a water absorbing agent, and a thixotropic agent may be blended.

Examples of the rust preventive include various rust preventive pigments, zinc phosphate, tannic acid derivatives, phosphate esters, basic sulfonates and the like. Examples of the plasticizer include phthalic acid ester, adipic acid ester, sebacic acid ester and tricresyl phosphate. Fillers include calcium carbonate, carbon black, glass powder,
Clay, powdered silica gel, ultrafine silica powder, molecular sieves and the like can be mentioned.

The method for producing the primer composition of the present invention is not particularly limited. For example, a polysiloxane compound, an organic solvent, and, if necessary, a polyisobutylene compound having a terminal silyl group, The composition, a kneading agent, a silanol condensation catalyst and other additives are appropriately added, kneaded sufficiently using a mixing device such as a ball mill, and uniformly dispersed to obtain a composition.

The primer composition thus obtained has a high tackiness, which is a characteristic of polyisobutylene, and has excellent adhesion to adherends having various different surface morphologies. Further, the obtained cured product has excellent properties of polyisobutylene and silicone, heat resistance,
Oxidation resistance, weather resistance, aging resistance, warm water resistance, moisture resistance,
Excellent electrical properties.

The primer composition of the present invention having such properties is suitable as a primer for bonding an adherend having various surface morphologies and a sealing material. As the sealing material, in addition to those containing a saturated hydrocarbon-based polymer as a main component, for example, those using an inorganic polymer such as silicone, modified silicone-based, polysulfide-based, polyurethane-based, and acrylic urethane-based are also suitably used. be able to.

[0048]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to these. (Examples 1 to 15) Polysiloxane compound, mixed solution of n-hexane and xylene as a solvent, polyisobutylene compound having a silyl group at a terminal (referred to as polyisobutylene compound in the table), silanol condensation catalyst, silane coupling The agents were blended in the composition shown in Table 1 and kneaded uniformly to obtain a primer composition.

(Comparative Examples 1 and 2) A primer composition was obtained in the same manner as in Example except that no polysiloxane compound was contained.

<Adhesion Test> The primer compositions obtained in Examples and Comparative Examples were applied to an aluminum plate, a glass plate, an acrylic electrodeposited copper plate, a fluorine-baked copper plate, a two-part silicone sealant, and a mortar plate. After curing, a sealing material having the composition shown in Table 2 was applied in a thickness of 6 mm, and the adhesion was evaluated under the following conditions.

Initial Adhesion After being left for 10 days at 20 ° C. and 55% RH, it was peeled off by hand. Warm water adhesion 10 under conditions of 20 ° C and 55% RH
After standing for a day, they were immersed in water at 40 ° C. for 7 days, and then peeled off by hand. The test method was performed in accordance with the simple adhesion test method described in the Building Sealant Handbook (edited by the Japan Sealant Manufacturers Association). The criteria for the determination are as follows. ：: Sealing material break △: Thin layer peeling ×: Interfacial peeling ：: Mixed. Table 1 shows the results.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

[Table 3]

<Each component in Table 1> The polysiloxane compounds 1 to 4 have the following structures.

[0056]

Embedded image

Solvent 1: n-hexane (Kanto Chemical Co., Ltd.)
Solvent 2: Xylene (manufactured by Kanto Chemical Co., Ltd.) Polyisobutylene compound: a composition containing 50 parts by weight of process oil per 100 parts by weight of terminal silane-modified PIB oligomer, EPION E100S (manufactured by Kanebuchi Chemical Industry Co., Ltd.) ) Silanol condensation catalyst 1: organic titanate, TPT-10
0 (manufactured by Nippon Soda Co., Ltd.) Silanol condensation catalyst 2: tin compound, SCAT ^# 27
(Manufactured by Sankyoki Gosei Co., Ltd.) Silane coupling agent: aminosilane, A1110 (manufactured by Nippon Unicar Co., Ltd.) Silicone sealant: two-part silicone sealant, silicone 70 (manufactured by Yokohama Rubber Co., Ltd.)

[0058]

[Table 4]

<Each component in Table 2> Polyisobutylene compound: a composition containing 50 parts by weight of a process oil per 100 parts by weight of a PIB oligomer modified with a silane terminal, EPION505S (Kanebuchi Chemical Industry Co., Ltd.)
Process oil: PAO5004 (Idemitsu Petrochemical Co., Ltd.)
Fatty acid-treated calcium carbonate: SERETS 200 (manufactured by Maruo Calcium Co., Ltd.) Heavy calcium carbonate: Super S (manufactured by Maruo Calcium Co., Ltd.) Epoxy resin: Bisphenol A type epoxy resin, Epicoat 828 (Yuika Shell Epoxy Co., Ltd. )) Thixotropic agent: hydrogenated castor oil-type thixotropic agent, Dispalon ^# 305
(Kusumoto Kasei Co., Ltd.) Antioxidant 1: Tinuvin 327 (Ciba Geigy Co., Ltd.)
Antioxidant 2: Sanol LS770 (manufactured by Ciba-Geigy) Antioxidant 3: Irganox 1010 (manufactured by Ciba-Geigy) Laurylamine: Farmin 20D (manufactured by Kao Corporation) Tin catalyst: divalent tin Compound, Neostan U-28 (Nitto Kasei Co., Ltd.)

As is clear from Table 1, the adhesiveness to various adherends is improved by containing the polysiloxane compound. In addition, by containing a silanol condensation catalyst and a silane coupling agent, good adhesion to adherends such as a two-part silicone sealant and mortar can be obtained.

[0061]

As described above, since the primer composition of the present invention has a hydrolyzable silyl group, a polyisobutylene structure and a siloxane bond, the primer composition is particularly excellent in the adhesiveness of the binder component and has various surface morphologies. Improves the adhesion to the adherend. The primer composition of the present invention further contains a polyisobutylene, a silane coupling agent, and a silanol condensation catalyst, if necessary, to further improve adhesion to an adherend and adhesion to a cured composition. If the sealing material is used as a primer of a polyisobutylene-based saturated hydrocarbon polymer, the resulting cured product will have heat resistance, oxidation resistance, weather resistance, aging resistance, hot water resistance, moisture resistance, and electrical properties. Is excellent.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 CP041 CP051 CP091 EX026 EX036 EX056 EX066 EX076 FD146 FD207 GH01 GJ01 HA05 4J038 CL001 CL002 DL031 DL131 DL132 GA15 JC30 KA06 MA14 NA03 NA04 NA14

Claims (5)

[Claims] 1. A primer composition comprising a polymer having a degree of polymerization of 20 or more and having a hydrolyzable silyl group, a polyisobutylene structure and a siloxane bond, and an organic solvent. 2. An organic solvent comprising a polysiloxane compound (A) having a siloxane structure represented by the following formula (1) and / or a polysiloxane compound (B) having a siloxane structure represented by the following formula (2): A primer composition comprising: Embedded image In the formula, X is a polyisobutylene optionally having a silyl group at a terminal, and Y is an alkyl group having 1 to 18 carbon atoms optionally having a silyl group at a terminal. Z is a hydrolyzable group. a, b, c, d, and e are integers, and a / a + b
= 0.01-0.9, b / a + b = 0.01-0.7,
c / c + d + e = 0.01 to 0.7, d / c + d + e =
0 to 0.9 and e / c + d + e = 0 to 0.9. 3. The primer composition according to claim 1, wherein the primer composition further comprises a polyisobutylene compound having a silyl group at a terminal. 4. The primer composition according to claim 1, wherein the primer composition further contains a silane coupling agent. 5. The primer composition according to claim 2, wherein the primer composition further contains a silanol condensation catalyst.