JPH108021A - Vulcanizable adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vulcanizable adhesive composition, comprising a y- glycidoxypropyltrialkoxysilane, etc., an organotitanium compound, an alcoholic organic solvent and water, capable of remarkably simplifying bonding processes and suitable for bonding a metal to an acrylic rubber, etc. SOLUTION: This vulcanizable adhesive composition comprises (A) 43 pts.wt. γ-glycidoxypropyltrialkoxysilane, (B) 100 pts.wt. γ-aminopropyltrialkoxysilane, (C) 71 pts.wt. organotitanium compound such as titanium tetraacetylacetonate, (D) 1400 pts.wt. alcoholic organic solvent such as isopropanol and (E) 280 pts.wt. water. Furthermore, the vulcanizable adhesive composition is preferably used to carry out the vulcanization bonding of a metal to an acrylic rubber or a fluororubber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a vulcanized adhesive composition. More specifically, the present invention relates to a vulcanized adhesive composition which is suitably used for vulcanization bonding between a metal and an acrylic rubber or a fluororubber.

[0002]

2. Description of the Related Art Conventionally, a phenol resin-based adhesive has been used for vulcanization bonding between metal and acrylic rubber.
When using a phenolic resin adhesive, about 150 to 200
It is unavoidable that the bonding process becomes complicated, for example, high-temperature baking at about 10 ° C. for about 10 minutes and application and baking about 2 to 3 times to improve the adhesiveness are required.

Accordingly, the present inventors have previously described a vulcanized adhesive composition which can be effectively used for vulcanization bonding between a metal and an acrylic rubber and which can greatly simplify the bonding treatment step. -A vulcanized adhesive composition containing at least one of mercaptopropyl trialkoxysilane and γ-glycidoxypropyl trialkoxysilane, γ-aminopropyl trialkoxysilane, an organic titanium compound and an organic solvent has been proposed. No. 7-316106).

[0004] Although the proposed vulcanized adhesive composition achieves its intended purpose, its adhesiveness is not always sufficient depending on the type of acrylic rubber having a crosslinking site other than active chlorine. If the metal to which the sulfur adhesive composition is applied is left unattended, the adhesiveness is reduced, and even if the purpose of vulcanization adhesion with acrylic rubber is achieved, it does not vulcanize with fluororubber. Have a point.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is not only to greatly simplify the bonding process, but also to vulcanize and bond various acrylic rubbers and metals regardless of the type of crosslinking site. It is still another object of the present invention to provide a vulcanized adhesive composition which can be effectively used for vulcanized adhesion between a fluororubber and a metal.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
This is achieved by a vulcanized adhesive composition containing γ-glycidoxypropyl trialkoxysilane, γ-aminopropyl trialkoxysilane, an organic titanium compound, an alcoholic organic solvent and water.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As γ-glycidoxypropyl trialkoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane and the like are used. As the γ-aminopropyl trialkoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane and the like are used. Further, as the organic titanium compound, for example, tetraisopropyl titanate, tetra n-butyl titanate, tetra (2-ethylhexyl) titanate and the like are also used, but preferably a compound of the general formula A titanium acetylacetonate compound represented by the following formula is used.

Each of the above-mentioned components contains γ-glycidoxypropyl trialkoxysilane in an amount of about 5 to 100 parts by weight, preferably about 40 to 50 parts by weight, based on 100 parts by weight of γ-aminopropyl trialkoxysilane. The organic titanium compound is used in an amount of about 20 to 100 parts by weight, preferably about 40 to 80 parts by weight.

The vulcanized adhesive composition containing these components as essential components is an alcoholic organic solvent used in an amount of about 10 to 100 times the weight of γ-aminopropyl trialkoxysilane, such as methanol, ethanol, etc. Alcohols such as isopropanol, and preferably a mixed organic solvent of methanol or ethanol and isopropanol (when used in a mixing weight ratio of about 2: 8 to 6: 4, good flowability to metal and good liquid stability) It is prepared and used as a solution of an aqueous organic solvent which is a mixed solution with water used in an amount of about 1 to 20 times. Preparation of the vulcanized adhesive composition as an aqueous organic solvent solution can be easily performed by stirring for only a few minutes at room temperature.

In the vulcanization bonding using an adhesive comprising such a composition, the vulcanized adhesive composition is immersed and applied on a metal such as mild steel, stainless steel or aluminum, and air-dried at room temperature for about 10 minutes. After that, an unvulcanized acrylic rubber compound, a fluorine rubber compound, or the like is bonded thereto, and the used rubber is vulcanized under pressure.

As the acrylic rubber, those containing any of a crosslinkable group such as an active halogen, a carboxyl group, a hydroxyl group, an epoxy group, an amide group, and an unsaturated group derived from a diene are used. As the unvulcanized acrylic rubber compound, in addition to a crosslinking agent according to the type of these crosslinking groups, a crosslinking aid, an acid acceptor, a filler, a reinforcing agent, an antioxidant, a pigment, etc. are appropriately provided as necessary. The compounded one is used, and specific examples are as follows. (Formulation Example I) 100 parts by weight of active chlorine-containing acrylic rubber 70 parts by weight of HAF carbon black 5 parts by weight of powdered silica 2 parts by weight of microcrystalline wax (Sannok, Ouchi Shinko Chemical) 1 part by weight of stearic acid 4,4'-bis (2,2'-dimethylbenzyl) diphenylamine 2 parts by weight Sulfur 0.3 parts by weight Sodium stearate 3.5 parts by weight (Formulation Example II) Epoxy-containing acrylic rubber 100 parts by weight HAF carbon black 10 parts by weight Powdered silica 15 parts by weight Microcrystalline Wax (Sunnock) 2 parts by weight Stearic acid 1 part by weight Antioxidant (Ouchi Emerging Chemicals Nocrack White) 2 parts by weight Zinc dithiocarbamate 3 parts by weight

As the fluororubber, any of various types of fluororubbers typified by vinylidene fluoride copolymer can be used. Carbon black is used in the unvulcanized compound of these fluororubbers to be bonded. Fillers such as divalent metal oxides or hydroxides, polyol compounds, vulcanizing agents such as organic peroxides and other necessary additives are appropriately blended. Are exemplified as follows. (Formulation Example III) Fluoro rubber (Dupont Viton E45) 100 parts by weight Calcium metasilicate 40 parts by weight MT carbon black 2 parts by weight Magnesium oxide (Kyowa Chemicals Magnesia # 150) 6 parts by weight Calcium hydroxide 3 parts by weight Sulfurizing agent (Curative # 30 from DuPont) 2 parts by weight Vulcanization accelerator (Curative # 20 from the company) 1 part by weight (Formulation Example IV) Fluorine rubber (Daikin product Daiel G901) 100 parts by weight Calcium metasilicate 20 parts by weight MT carbon black 20 parts by weight Magnesium oxide (Magnesia # 150) 6 parts by weight Calcium hydroxide 3 parts by weight Triallyl isocyanurate 1.8 parts by weight Organic peroxide (Nippon Oil & Fats product Perhexa 25B) 0.8 parts by weight

[0013]

The vulcanized adhesive composition according to the present invention does not require a baking treatment or the like, can be applied to metal only by air drying, and has a sufficient adhesive force with only one application. As a result, the bonding step can be greatly simplified. This vulcanized adhesive composition can be used for vulcanization bonding between metal and various rubbers, and is particularly preferably used for vulcanization bonding between metal and acrylic rubber or fluororubber. The vulcanization bonding is carried out satisfactorily regardless of the type of the crosslinking site.

[0014]

Next, the present invention will be described by way of examples.

Example (vulcanized adhesive I) 100 parts by weight of γ-aminopropyltriethoxysilane 43 parts by weight of γ-glycidoxypropyltrimethoxysilane 71 parts by weight of titanium tetraacetylacetonate 1400 parts by weight of isopropanol 940 parts by weight of methanol Water 280 parts by weight (vulcanizing adhesive II) γ-aminopropyltriethoxysilane 100 parts by weight γ-glycidoxypropyltrimethoxysilane 43 parts by weight Titanium dibutoxydiacetylacetonate 71 parts by weight Isopropanol 1240 parts by weight Methanol 830 parts by weight Water 570 parts by weight (vulcanizing adhesive III) γ-mercaptopropyltriethoxysilane 100 parts by weight γ-aminopropyltriethoxysilane 25 parts by weight Tetraisopropyl titanate 6 parts by weight Methanol 1535 parts by weight (vulcanizing adhesive IV) γ- Aminopropyltriethoxysilane 100 parts by weight γ-glycidoxypro Rutrimethoxysilane 43 parts by weight Titanium tetraacetylacetonate 71 parts by weight Isopropanol 1400 parts by weight Methanol 940 parts by weight (vulcanized adhesive V) γ-aminopropyltriethoxysilane 100 parts by weight γ-glycidoxypropyltrimethoxysilane 43 parts by weight Parts titanium dibutoxydiacetylacetonate 71 parts by weight isopropanol 1400 parts by weight methanol 940 parts by weight

(Commercial adhesive) Commercial phenolic resin adhesive
(Toyo Chemical Laboratory product Metalloc N-15)

Each of the above vulcanized adhesives was applied on a mild steel sheet treated with zinc phosphate, and left standing at room temperature for 10 minutes to air-dry. In the case of a commercially available phenolic resin-based adhesive, leave it at room temperature for 10 minutes and allow it to air dry.
For 10 minutes. The unvulcanized rubber compounds of Formulation Examples I to IV were joined to these vulcanized adhesives or adhesive-coated mild steel sheets.
4 minutes at 210 ° C, and 4 minutes at 180 ° C for Formulation Examples III to IV.
The resulting adhesive was subjected to a 90 ° peel test (based on JIS K-6301), and the peel force and the remaining rubber area were measured.

The results obtained are shown in the following table. Formulation Example I Formulation Example II Peeling force Rubber remaining area Peeling force Rubber remaining area Vulcanized adhesive (N / mm) (%) (N / mm) (%) I 4.7 100 5.0 100 II 4.6 100 5.0 100 III 4.7 100 3.1 50 IV 2.4 30 2.3 30 V 2.2 10 2.1 10 (Commercial adhesive) 3.2 50 3.0 50 Formulation example III Formulation example IV Peeling force Rubber remaining area Peeling force Rubber remaining area Vulcanized adhesive (N / mm) (%) (N / mm) (%) I 5.4 100 5.2 100 II 5.4 100 5.1 100 III 0.9 10 0.6 0 IV 3.8 50 3.7 50 V 3.6 40 3.4 30 (commercial adhesive) 0 0 0 0

Claims (3)

[Claims] 1. γ-glycidoxypropyl trialkoxysilane, γ-aminopropyl trialkoxysilane,
A vulcanized adhesive composition comprising an organic titanium compound, an alcoholic organic solvent and water. 2. The vulcanized adhesive composition according to claim 1, which is used for vulcanization bonding between a metal and an acrylic rubber. 3. The vulcanized adhesive composition according to claim 1, which is used for vulcanized adhesion between a metal and a fluororubber.