JPH0725952A - Adhesive fluororubber and laminate using the same - Google Patents

Abstract

(57) [Summary] [Structure] Adhesive fluororubber obtained by grafting tetrafluoroethylene-propylene copolymer fluororubber with one or more compounds selected from unsaturated carboxylic acids, acid anhydrides and esters thereof, And a laminate using the same. [Effect] It has strong adhesion and excellent properties of tetrafluoroethylene-propylene copolymer fluororubber, and can be used in various industrial fields by coating various natural or synthetic resins, metals, ceramics, concrete, etc. Is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive fluororubber and a laminate using the same, and more specifically to an adhesive fluororubber having good adhesiveness to other organic or inorganic materials and a laminate using the same. Regarding the body

[0002]

2. Description of the Related Art Tetrafluoroethylene-propylene copolymer fluororubber is used in a wide range of fields because it is excellent in oil resistance, heat resistance, weather resistance, etc., and is used in inorganic materials such as metals and glass, natural or synthetic resins. Adhesion with organic materials such as is often required.

[0003]

However, in order to firmly bond the fluororubber to the above-mentioned inorganic or organic material, it was necessary to use a primer or carry out a surface treatment.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, in which an unsaturated carboxylic acid, its acid anhydride and its ester are added to tetrafluoroethylene-propylene copolymer type fluororubber. Selected from 1
An adhesive fluororubber obtained by graft copolymerizing at least one compound is provided.

The tetrafluoroethylene-propylene copolymer type fluororubber used in the present invention is obtained by copolymerizing tetrafluoroethylene and propylene at a ratio of 30/70 to 70/30 (molar ratio) or further one kind. Alternatively, other fluorinated olefins or hydrocarbon-based olefins are copolymerized.

The copolymerizable olefins include α-olefins such as ethylene and butene, fluorine-containing olefins such as hexafluoropropylene, vinylidene fluoride (perfluorobutyl) ethylene and trifluorochloroethylene, ethyl vinyl ether and perfluoromethyl. Examples thereof include vinyl ethers such as vinyl ether and perfluoropropyl vinyl ether, and fluorine-containing acrylates. When copolymerizing these olefins, it is preferable to copolymerize them in the polymer within a range of 50 mol% or less.

In producing the fluororubber used in the present invention, various conventionally known polymerization methods such as bulk polymerization, suspension polymerization, emulsion polymerization and solution polymerization can be adopted. The fluororubber used in the present invention can be used in any molecular weight range.

Here, it is important that the polymer of fluororubber is grafted with one or more compounds selected from unsaturated carboxylic acids, their acid anhydrides and their esters as adhesive functional groups. By introducing these compounds, a large adhesive force can be obtained even for those which cannot be sufficiently adhered or which cannot be adhered without using a conventional primer or the like.

As the compound to be grafted, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, bicyclo (2,2,1) hept-2-ene-5,6- Dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo (2,2,2
1) hept-2-ene-5,6-dicarboxylic acid anhydride,
Examples thereof include methyl acrylate, methyl methacrylate, dimethyl maleate, monomethyl maleate, diethyl fumarate, dimethyl itaconate, diethyl citracone, and dimethyl tetrahydrophthalic anhydride. These are used alone or in combination of two or more. Among these, unsaturated carboxylic acid or its anhydride, especially maleic anhydride is preferably used.

The amount of the above grafted compound used is
0.1 to 10 parts by weight with respect to 100 parts by weight of fluororubber,
It is preferably in the range of 0.2 to 5 parts by weight. As a method of grafting the above compound onto the fluororubber, a method of reacting both in the presence of a radical initiator, a method of copolymerizing tetrafluoroethylene and propylene, or the like can be adopted, The former method is preferably adopted. The grafting reaction may be performed while directly mixing the fluororubber and the above compound, or may be performed in a solution. It is efficient to carry out continuously in an extruder or the like.

The radical initiator used in the graft reaction has a decomposition temperature of 120 to 300 such that the half-life is 1 minute.
Those in the range of ° C are preferably used, specifically, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, 2,5-dimethyl-
2,5-di (peroxybenzoate) hexyne-3,
1,4-bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-
Butyl peracetate, 2,5-dimethyl-2,5-di (tert-butyl peroxy) hexyne-3,2,5
-Dimethyl-2,5-di (tert-butylperoxy) hexane, tert-butylperbenzoate, t
Organic peroxides such as ert-butyl perphenyl acetate, α, α′-azobisisobutyronitrile, 2,2 ′
Examples include azo compounds such as azobis (2-methylpropionitrile).

For example, the target fluororubber can be obtained by heating with an extruder or the like and carrying out a graft reaction while mixing within a residence time of several seconds to several hours. Adhesive fluororubber of the present invention, carbon, filler such as silica or glass fiber, carbon fiber within the range that does not impair the performance,
It is possible to mix a metal oxide, a pigment, an internal release agent, and other optional additives depending on the application. Further, it may be used by blending with other synthetic rubber, fluororesin, thermoplastic resin and the like. Further, the adhesive fluororubber of the present invention can be vulcanized and adhered by mixing a vulcanizing agent. In this case, an organic peroxide is used as a vulcanizing agent, and an unsaturated polyfunctional compound is preferably used as a vulcanizing aid.

Examples of the organic peroxide include benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (peroxybenzoate) hexyne-3,1,4-bis (t).
ert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butylperacetate, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3,2,5-dimethyl-2,
5-di (tert-butylperoxy) hexane, te
rt-Butyl perbenzoate, tert-butyl perphenyl acetate, etc. are used. As the unsaturated polyfunctional compound, triallyl isocyanurate, triallyl cyanurate, trimethylolpropane trimethacrylate, polybutadiene and the like are used.

The adhesive fluororubber thus obtained can be adhered or laminated to other organic or inorganic materials by a conventionally known method such as extrusion, coextrusion, calendering, coating, and insert molding using a die. Is. By these methods, for example, a laminated film of two layers of the fluororubber of the present invention and another polymer, a laminate of three or more layers in which the fluororubber of the present invention is used as an adhesive layer and another polymer is laminated, A metal coated with the fluororubber of the invention, an inorganic material such as glass or ceramics, a metal coated with another polymer using the fluororubber of the invention as an adhesive layer, an inorganic material such as glass or ceramics, and the like can be obtained. Further, the adhesive fluororubber of the present invention can be used as a surface treatment of powder or as a paint.

[0015]

[Function] By grafting an unsaturated carboxylic acid, an acid anhydride thereof or an ester thereof onto a tetrafluoroethylene-propylene copolymer type fluororubber, it is chemically bonded when it is bonded to another inorganic or organic material, It is considered that a strongly bonded laminate can be obtained without using a primer.

[0016]

EXAMPLES The present invention will be specifically described with reference to examples. In the examples, “part” means “part by weight”.

Example 1 Aflas 150E (tetrafluoroethylene / propylene = 55/45 (molar ratio), fluoro rubber made by Asahi Glass) 10
0 parts, 1.5 parts of maleic anhydride, and 1.5 parts of dicumyl peroxide were uniformly mixed in advance with a 2-roll,
Using a twin-screw extruder, the mixture was mixed at 200 ° C. for a residence time of 2 minutes to obtain a maleic anhydride-grafted fluororubber. This was laminated on a nylon 12 film with a calendar roll. When this peeling test was performed, the fluororubber cohesively failed.

Example 2 An iron pipe was coated with the maleic anhydride-grafted fluororubber obtained in Example 1. When this peeling test was performed, the fluororubber cohesively failed.

Example 3 100 parts of a fluororubber grafted with the maleic anhydride obtained in Example 1, 25 parts of MT carbon, 5 parts of magnesium oxide, 3 parts of triallyl isocyanurate, 1,4-
1 part of bis (tert-butylperoxyisopropyl) benzene was uniformly mixed with 2 rolls to obtain a fluororubber composition. Put this on an iron and stainless steel test piece and
Press vulcanization was performed at 70 ° C. for 20 minutes. When these peeling tests were conducted, the fluororubbers all failed cohesively.

Comparative Example 1 Aflas 150E was laminated on a nylon 12 film with a calendar roll. When this peeling test was performed, no adhesion was found.

Comparative Example 2 Aflas 150E 100 parts, MT carbon 25 parts, magnesium oxide 5 parts, triallyl isocyanurate 3 parts,
A fluororubber composition was obtained by uniformly mixing 1 part of 1,4-bis (tert-butylperoxyisopropyl) benzene with two rolls. This was laminated on an iron and stainless test piece and press-vulcanized at 170 ° C. for 20 minutes. When these peeling tests were performed, none of them adhered at all.

[0022]

The laminate obtained according to the present invention has a strong adhesive force and excellent properties of tetrafluoroethylene-propylene copolymer fluororubber, and various natural or synthetic resins, metals, ceramics, concrete, etc. Chemical resistance, solvent resistance, oil resistance, gas barrier property, water repellency, oil repellency, weather resistance, corrosion resistance, waterproof property, antifouling property, etc. by adhesion of, and adhesion of inorganic materials and organic materials, etc. Therefore, it can be used in various industrial fields.

Claims (5)

[Claims] 1. An adhesive fluororubber obtained by graft-copolymerizing a tetrafluoroethylene-propylene copolymer fluororubber with one or more compounds selected from unsaturated carboxylic acids, their acid anhydrides and their esters. 2. The adhesive fluororubber according to claim 1, which contains a vulcanizing agent. 3. A laminate comprising the adhesive fluororubber according to claim 1 and another polymer layer. 4. A laminate of the adhesive fluororubber according to claim 1 and an inorganic material. 5. A laminate of an inorganic material having the adhesive fluororubber of claim 1 as an adhesive layer and another polymer.