JPS5938896B2 - Laminate and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laminate and a method for producing the same, and more particularly to a novel laminate comprising fluororubber and epichlorohydrin rubber, and a method for producing the laminate comprising vulcanization bonding of both rubbers. .

Conventionally, fluororubber has been widely used as an industrial material because it has superior performance in terms of heat resistance, oil resistance, solvent resistance, chemical resistance, etc. compared to general general-purpose rubber. However, although fluororubber has these excellent properties, it is expensive, and it cannot be said to be excellent in low temperature resistance, for example, it has the disadvantage of losing its rubber elasticity at temperatures below -20°C. ing.

In order to compensate for these drawbacks of fluororubber, the present inventors conducted various studies on laminates with epichlorohydrin rubber, which is relatively inexpensive and has excellent low temperature resistance. We discovered that using this common vulcanization system significantly improves adhesion, which originally had problems in lamination due to poor compatibility between the two rubbers and different vulcanization systems. The present invention was completed.

That is, the present invention provides a laminate in which a vulcanized molded product of a fluorine rubber vulcanizing composition and a vulcanized molded product of an epichlorohydrin rubber vulcanizable composition containing a common vulcanization system are firmly adhered; The gist is the production method, and common vulcanization systems include preferably divalent metal oxides or hydroxides, fluorine-containing polyhydroxy compounds, and organic compounds containing nitrogen or phosphorus atoms in the molecule. We use a system consisting of

Therefore, according to the present invention, it is possible to firmly bond both rubbers without intervening any special treatment or adhesive for bonding, and it is possible to maintain the above-mentioned excellent properties of fluororubber while maintaining its drawbacks. It is possible to provide a laminate that can improve cost and low temperature resistance.

The fluororubbers useful in this invention are generally highly fluorinated, elastomeric copolymers.

Examples of these copolymers include copolymers of vinylidene fluoride and other copolymerizable fluorine-containing olefins, such as vinylidene fluoride and hexafluoropropene, pentafluoropropene, trifluoroethylene, Copolymers with one or more of trifluorochloroethylene, tetrafluoroethylene, vinyl fluoride, perfluoromethyl vinyl ether, perfluoropropyl vinyl ether, etc. are preferred. Among these, particularly preferred are vinylidene fluoride-hexafluoropropene binary copolymer and vinylidene fluoride-tetrafluoroethylene-hexafluoropropene ternary copolymer. Epichlorohydrin rubber is usually commercially available and includes epichlorohydrin homopolymers and epichlorohydrin/ethylene oxide copolymers, but in addition to or in place of ethylene oxide, other cenomeric components (epibromohydrin, propylene It may be a copolymer having one or more of oxide, styrene oxide, allyl glycidyl ether, etc.

The epichlorohydrin homopolymer and epichlorohydrin/ethylene oxide copolymer may be any elastomer containing -CH, Cl structural units in the molecular chain, and -CHX (X is chlorine, bromine, etc.) in the molecular chain. represents a halogen atom.

) structure. Essentially, any type of polymer that involves a dehalogenation reaction can be crosslinked, and is not particularly limited. Preferred divalent metal oxides or hydroxides that are common components of the vulcanization system include Ca0, Ca(0H)2, MgO,
Mg(0H)2, PbO, Pb304, Pb(OH)2
, BaO, Ba(OH)2, etc.

The amount used is 1 to 40 parts by weight, preferably 2 parts by weight, per 100 parts by weight of the above fluoro rubber or epichlorohydrin rubber.
~20 parts by weight, and may be varied as appropriate depending on the purpose. As the fluorine-containing polyhydroxy compound, 2,2-bis(4-hydroxyphenyl) perfluoropropane [
Bisphenol AF], 2,2-bis(4-hydroxyphenyl)tetrafluorodichloropropane, 2-(4
'-Hydroxyphenyl)-1,1,1,3,3,3-
Hexafluoro-2-propanol, HOCH2 (CF
2) 3CH20H, HOCH2CF2CFH (CF2)
3CFHCF2CH20H, HOCH2CH2CH2(
CF2)3CH,CH,-CH,OH or HOCH2C
Examples include F2CH2(CF2)3CH2CF2CH20H and alkali metal or alkaline earth metal salts of these compounds, with bisphenol AF being particularly preferred.

The amount used is O. It is 5 to 10 parts by weight, preferably 1 to 6 parts by weight. If the amount is less than this, the degree of crosslinking will be insufficient, and if it is more than this, there will be a tendency for the rubbery properties to be lost. Basic compounds containing nitrogen or phosphorus atoms in their molecules include:
Examples include the following compounds.

a) Compounds represented by the general formula: or and their inorganic or organic acid salts [
In the formula, R1, R2 and R3 have the same or different carbon number 1
~20 alkyl groups, one of which may be a cycloalkyl group, or two of R1, R2, and R3 may be fused to form a ring structure.

R4, R5, R6 and R7 have the same or different carbon number 1
~6 alkyl groups, . R4 and R6 and/or R5
and R7 may be bonded together to form a ring structure. R8 represents an alkylene group having 1 to 21 prime numbers.
]. b) Compounds represented by formula: or and general formula: or inorganic or organic acid salts thereof [wherein R9 is hydrogen, an alkyl group having 1 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, and RIO has 1 or more carbon atoms
It represents a 12 alkyl group or an aryl group having 6 to 12 carbon atoms.

]. c) A compound represented by the general formula: [wherein R', R'' and R'' represent the same or different alkyl groups or aryl groups having 1 to 20 carbon atoms.

]. One or more of these compounds may be appropriately selected and used.

The amount used is 0.5 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the fluororubber or epichlorohydrin rubber. If the amount is less than this, the crosslinking property will be poor, and if it is more than this, various properties will be adversely affected. Appropriate organic additives can be used in combination with both compositions used in the present invention, if necessary, thereby improving the plasticization, heat resistance, etc. of the vulcanizing composition.

Further, carbon black and other inorganic fillers can also be used together. To obtain the laminate of the present invention, for example, first, a fluororubber vulcanizing composition and an epichlorohydrin vulcanizing composition are kneaded by a known method and formed into a sheet of uniform thickness. Then, one or more layers of these are alternately stacked one on top of the other, and pressure vulcanization is performed using a heat press or a vulcanizing can to vulcanize and bond both rubber sheets. Alternatively, a method may be adopted in which both of the above compositions are formed into a laminated tube by two-color extrusion and pressure vulcanized using a vulcanizer.

At this time, the heat press is usually at a temperature of 150 to 170°C.
20~100kg/(-JMo V1 pressure, 10~60
When using a vulcanizer, it is usually 145~
At a temperature of 115°C and a pressure of 4-7 kg/Cit, 30
Pressure vulcanization is carried out for ~120 minutes.

Furthermore, in addition to these pressure vulcanizations, oven vulcanization (for example, at 150° C. for about 3 hours) may be performed if necessary. The laminate obtained in this way has a strong enough bond to withstand long-term use, and while retaining the excellent properties of fluorocarbon rubber, its disadvantages of price and low temperature resistance can be overcome. It is something to improve.

The laminate of the present invention has the oil resistance of fluororubber, especially excellent resistance to degraded gasoline that is not found in other rubbers, and by utilizing this property, it can be used as fuel for aircraft, automobiles, and other fields. It can be used as a system material, for example, for gasoline hoses.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples.

Examples Each of the epichlorohydrin rubber compound compositions shown in Table 1 (the proportions are expressed in parts by weight) and the fluoro rubber compound compositions shown in Table 2 (the proportions are expressed in parts by weight) were each rolled under water cooling. A sheet with a uniform thickness of approximately 1.5 m1i was prepared by kneading.

Each sheet was cut into 6 crn x 10 CrIL squares, a fluoro rubber sheet was superimposed on each epichlorohydrin rubber sheet, and the sheets were crosslinked and laminated under pressure at 160° C. for 30 minutes using a heat press. For the part to be held between the grips during the peel test, a polytetrafluoroethylene film having a thickness of approximately one fin was placed between the two sheets at one end of the sheet in advance to prevent the two sheets from being laminated. The obtained laminate was cut into strips with a width of 1 inch, and the test piece was subjected to a peel test in accordance with JIS K63Ol at a tensile rate of 5011/-. The peel strength (Kg/1 nch) at the bottom was measured.

The results are shown in Table 3. Looking at Table 3, it can be seen that the epichlorohydrin rubber and the fluorine rubber are laminated with sufficient adhesive strength.

Claims (1)

[Scope of Claims] 1. A laminate formed by firmly adhering a vulcanized molded product of a fluororubber vulcanizing composition and a vulcanized molded product of an epichlorohydrin rubber vulcanizable composition containing a common vulcanization system. 2. The composition for vulcanizing fluororubber is composed of fluororubber, a divalent metal oxide or hydroxide, a fluorine-containing polyhydroxy compound, and an organic compound containing a nitrogen or phosphorus atom in the molecule, and is an epichlorohydrin rubber vulcanizing composition. 2. The laminate according to item 1, wherein the material is epichlorohydrin rubber, a divalent metal oxide or hydroxide, a fluorine-containing polyhydroxy compound, and an organic compound containing nitrogen or phosphorus atoms in the molecule. 3 Fluororubber or epichlorohydrin rubber 100
1 to 4 parts by weight of divalent metal oxide or hydroxide
0 parts by weight, 0.5 to 10 fluorine-containing polyhydroxy compounds
2. The laminate according to item 2, further comprising 0.5 to 10 parts by weight of an organic compound containing nitrogen or phosphorus atoms in the molecule. 4. A method for producing a laminate, which comprises stacking a molded product of a fluororubber vulcanizing composition and a molded product of an epichlorohydrin vulcanizing composition containing a common vulcanization system, and vulcanizing and adhering them.