JP2002012726A - Fluorinated elastic copolymer composition and vulcanized product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition of a fluorinated elastic copolymer which gives a vulcanized product excellent in hot water resistance, and the vulcanized product thereof. SOLUTION: A fluorinated elastic copolymer composition having a mass ratio of 100/1-50/0.3-10 in a fluorinated elastic copolymer/an ethylene-propylene- nonconjugated-diene copolymer (a mass ratio of each polymeric unit is 45-75/10-53/2-15)/an organic peroxide is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorine-containing elastic copolymer composition which gives a vulcanizate having excellent hot water resistance and a vulcanizate thereof.

[0002]

2. Description of the Related Art Fluorine-containing elastic copolymers are excellent in oil resistance, chemical resistance, heat resistance, weather resistance, surface characteristics and the like.
Used in a wide range of fields. In applications such as food processing processes, medical sterilization processes, and papermaking processes, they are used as gaskets and sealing materials by taking advantage of water resistance, hot water resistance, and steam resistance. Vulcanizates of fluorinated elastic copolymers with organic peroxides have better water resistance than those vulcanized with other vulcanizing agents, but are particularly resistant to compression in hot water environments. Hot water such as strain was not always at a satisfactory level.

[0003] On the other hand, ethylene-
A composition containing a propylene-based copolymer (hereinafter referred to as EP) is described in JP-A-11-124482. In the examples of the publication, a fluorine-containing elastic copolymer composition containing a small amount of a binary copolymer of ethylene (hereinafter, referred to as E) and propylene (hereinafter, referred to as P) is obtained by demolding after vulcanization. Sometimes low adhesion to mold. However, the publication does not describe or suggest hot water resistance, and heat resistance is not at a sufficiently satisfactory level.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a fluorinated elastic copolymer composition which gives a vulcanizate having excellent hot water resistance and its vulcanization. It is intended to provide a sulphate.

[0005]

The present invention relates to (a) a fluorine-containing elastic copolymer, (b) E / P / non-conjugated diene (hereinafter referred to as "E / P / non-conjugated diene").
It is called DM. )) Is 45 to 7 by mass.
It contains an ethylene-propylene-nonconjugated diene copolymer (hereinafter referred to as EPDM) of 5/10 to 53/2 to 15 and (c) an organic peroxide, and based on 100 parts of the component (a). 1 to 50 parts (particularly 6 to 40 parts) of component (b)
And 0.3 to 10 parts of the component (c). Also,
A vulcanizate obtained by vulcanizing the fluorinated elastic copolymer composition is provided. In addition, in this specification, a part means a mass part.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As the component (a) in the present invention, various components are used. As specific examples, a tetrafluoroethylene (hereinafter, referred to as TFE) -P copolymer, a TFE-P-vinylidene fluoride (hereinafter, referred to as VdF) copolymer, and a VdF-hexafluoropropylene (hereinafter, referred to as HFP). Copolymer, VdF-HFP-
TFE copolymer, VdF-TFE-ethyl vinyl ether (hereinafter referred to as EVE) copolymer, TFE-PV
dF-EVE copolymer, VdF-perfluoro (3,6
-Dioxa-5-methyl-1-decene) (hereinafter referred to as PHV
E. ) Copolymer, VdF-TFE-PHVE copolymer, ethylene-PHVE copolymer, TFE-perfluoro (methyl vinyl ether) (hereinafter, referred to as PMVE) copolymer, TFE-perfluoro (propyl vinyl ether) (hereinafter, PPVE) ) -VdF copolymer and the like, and are usually used alone or as a mixture of two or more.

The component (a) in the present invention is produced by copolymerization of two or more fluorine-based monomers or copolymerization of a fluorine-based monomer and a hydrocarbon-based comonomer. Hydrogen comonomer may be used alone or in combination of two or more.

[0008] As the fluorine-based monomer, TFE, Vd
F, fluorinated olefin monomers such as ethylene trifluoride chloride, vinyl fluoride, HFP and pentafluoropropylene; and perfluoro (alkyl vinyl ether) monomers such as PMVE, PPVE and PHVE. Further, as the hydrocarbon comonomer, E,
Hydrocarbon olefin monomers such as P and butene, E
Examples thereof include alkyl vinyl ether monomers such as VE and butyl vinyl ether. The copolymerization between the fluorine-based monomers and between the fluorine-based monomers and the hydrocarbon-based comonomers is carried out at an arbitrary ratio depending on the physical properties required for the vulcanized product.

In order to accelerate the vulcanization of the fluorinated elastic copolymer composition of the present invention, it is also preferable to use, as the component (a), a fluorinated elastic copolymer having a bromine atom or an iodine atom in the molecule. Such a fluorine-containing elastic copolymer is produced by adding a chain transfer agent or a monomer having a bromine atom or an iodine atom when copolymerizing the above-mentioned fluorine-containing monomer or the like.

Specific examples of the chain transfer agent include perfluoro (1,4-diiodobutane), perfluoro (1-bromo-4-iodobutane), perfluoro (1,6-diiodohexane), and perfluoro (1,8-diodohexane). Iodooctane) and the like. Specific examples of the monomer include perfluoro (3-iodo-1-propene), perfluoro (4-iodo-1-butene), perfluoro (4-bromo-1-butene), and perfluoro (5-bromo-3-oxa- 1-pentene), perfluoro (6-
Iodo-1-hexene) and the like.

The polymerization mode at the time of producing the component (a) includes:
Methods such as bulk polymerization, suspension polymerization, emulsion polymerization, and solution polymerization can be employed. When classified by the type of initiation reaction, radical polymerization using an organic peroxide initiator or an azo-based initiator, polymerization using a redox catalyst, polymerization using ionizing radiation, polymerization using heat or light, etc. Is appropriately adopted. The molecular weight of the fluorine-containing elastic copolymer as the component (a) is usually preferably in the range of 2 × 10 ^{3 to} 5 × 10 ⁵ .

The component (b) in the present invention is EPDM. As DM, a non-conjugated diene having no fluorine atom is usually used, and preferably ethylidene norbornene (hereinafter, referred to as ENB) or dicyclopentadiene (hereinafter, referred to as DCPD). The ratio of each polymerization unit of E / P / DM is 45 to 75/53 to 10/2 to 1 by mass ratio.
When EPDM of No. 5 is used, the hot water resistance of the vulcanized fluorine-containing elastic copolymer is remarkably improved. If the ratio of the polymerized units of DM is less than 2, the effect of improving the hot water resistance is insufficient, and if it is more than 15, the vulcanization density increases and the elasticity of the vulcanizate is lost.

The component (b) has a molecular weight of 2 × 10 ^{3 to} 5 ×.
Solid EPDM is preferable from the liquid at 10 ^5. (B)
The amount of the component used is 1 to 5 with respect to 100 parts of the component (a).
0 parts. When the amount is less than 1 part, the hot water resistance is not sufficiently improved, and when the amount is more than 50 parts, the heat resistance and chemical resistance of the vulcanized product are reduced. More preferably, it is 6 to 40 parts.

The component (c) in the present invention is a vulcanizing agent for the components (a) and (b), and employs an organic peroxide. Specific examples of the organic peroxide include peroxyketal, dialkyl peroxide, diacyl peroxide, peroxyester, and hydroperoxide. Specific examples include benzoyl peroxide,
Dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane, 2,5-dimethyl-2,5
-Bis (t-butylperoxy) hexyne-3, α,
α'-bis (tert-butylperoxy) -p-diisopropylbenzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane and the like can be mentioned.

The amount of component (c) used is 10% of component (a).
0.3 to 10 parts for 0 part. If the amount is less than 0.3 part, vulcanization becomes insufficient. If the amount is more than 10 parts, the vulcanization proceeds excessively, and the elasticity of the vulcanized product is lost. More preferably, it is 0.5 to 3 parts.

In the present invention, it is also preferable to add a vulcanization aid, a vulcanization accelerator, an acid acceptor and the like. Examples of the vulcanization aid include unsaturated polyfunctional compounds.Specific examples include triallyl isocyanurate, triallyl cyanurate, trimethylolpropane trimethacrylate, and polybutadiene. Organic compounds may be mentioned. The preferable amount of the vulcanization aid is 0.1 to 20 parts, more preferably 0.5 to 10 parts, per 100 parts of the component (a).

The vulcanization accelerator is particularly effective when the component (a) contains polymerized units of VdF. As the vulcanization accelerator, organic onium compounds such as organic quaternary ammonium salts and organic quaternary phosphonium salts, nitrogen-containing organic compounds such as amines and imines, and organic phosphorus compounds such as phosphine and phosphite are preferably used.

Specific examples of the vulcanization accelerator include tetrabutylammonium hydrogen sulfate, tetrabutylammonium bromide, 8-benzyl-1,8-diazabicyclo [5.
4.0] Undec-7-enium chloride, 1,8-diazabicyclo [5.4.0] undec-7-enium p-toluenesulfonate, tetrabutylphosphonium chloride, trioctylmethylphosphonium chloride, triphenylbenzylphosphonium Chloride, 1,8-diazabicyclo [5.4.0] undecene-7, pyridine,
Tributylamine, triphenylphosphine, tributylphosphite, and the like. The preferred amount of the vulcanization accelerator is 0.05 to 1 based on 100 parts of the component (a).
0 parts, more preferably 0.1 to 5 parts.

As the acid acceptor used in combination with the vulcanization accelerator, an oxide or hydroxide of a divalent metal is used. Specific examples include hydroxides and oxides such as magnesium, calcium, lead, and zinc. The preferred compounding amount of the acid acceptor is 1 to 50 parts, more preferably 1 to 30 parts, per 100 parts of the component (a).

The fluorine-containing elastic copolymer composition of the present invention may further contain various compounds conventionally used for producing various vulcanized rubbers. Specific examples include carbon black, silica, clay, talc,
Fillers such as glass fiber, pigments, antioxidants, stabilizers,
Examples include processing aids, internal release agents, vulcanization retardants, resins and rubbers other than the components (a) and (b).

The fluorinated elastic copolymer composition of the present invention comprises:
It is easily manufactured by uniformly mixing the above components with a rubber mixing device such as a roll, a kneader, a Banbury mixer, and an extruder. The fluorinated elastic copolymer composition of the present invention is usually vulcanized simultaneously with molding like press vulcanization, but may be vulcanized after molding. As the molding method, compression molding, injection molding, extrusion molding, calender molding or dipping or coating by dissolving in a solvent is employed.

Various vulcanization conditions are adopted in consideration of the molding method and the shape of the vulcanized product.
A range of several seconds to 24 hours at ° C is preferably employed. Secondary vulcanization is preferably employed for the purpose of improving the mechanical properties and compression set of the vulcanized product and stabilizing other properties.
The secondary vulcanization conditions are 100 to 300 ° C. for 30 minutes to 4 minutes.
About 8 hours are preferable.

The vulcanizates of the present invention include vulcanizates in the form of sheets, rings, tubes and the like. Also,
Applications include gaskets, sealing materials, O-rings,
Coating materials and the like are mentioned, and they are most preferably applied particularly to applications requiring hot water resistance, steam resistance and water resistance.

[0024]

EXAMPLES The present invention will be specifically described below with reference to Examples (Examples 1 to 6 and 10) and Comparative Examples (Examples 7 to 9 and 11), but the present invention is not limited thereto. The components were uniformly mixed with two rolls at the blending amounts (units: parts) shown in Table 1 to obtain a fluorinated elastic copolymer composition. After press vulcanization of this fluorinated elastic copolymer composition at 170 ° C for 20 minutes, secondary vulcanization was performed at 200 ° C for 4 hours. Using the obtained vulcanized sheet, the tensile strength (unit: MPa) and elongation at break (unit:%) were measured according to JIS K6251, and the hardness (unit: J) was measured according to JIS K6253.
ISA) was measured. Further, according to JIS K6262, the compression set (unit:%) in hot water after treatment in hot water at 140 ° C. for 70 hours was measured using a closed container. In addition, the composition was kept at 200 ° C. for 70 hours in accordance with JIS K6252 for heat aging resistance (change in tensile strength (unit:%), change in elongation at break (unit:%), change in hardness (unit: JIS).
A)) was measured. Table 1 shows the results.

[0025]

[Table 1]

The components in Table 1 are as follows. A: TEF-P copolymer (Afras 150 manufactured by Asahi Glass Co., Ltd.)
P). B: TEF-P-VdF copolymer (Afras SP manufactured by Asahi Glass Co., Ltd.). C: VdF-HFP-TFE copolymer (Daikin G902 manufactured by Daikin Industries, Ltd.).

D: EP-ENB copolymer (E polymerization unit / P polymerization unit / ENB polymerization unit = 50/46/4 (mass ratio), Esplene 505 manufactured by Sumitomo Chemical Co., Ltd.). E: EP-ENB copolymer (E polymerization unit / P polymerization unit / ENB polymerization unit = 71/23/6 (mass ratio), Esplen 582F manufactured by Sumitomo Chemical Co., Ltd.). F: EP-DCPD copolymer (E polymerization unit / P polymerization unit / DCPD polymerization unit = 62/35/3 (mass ratio), Esplene 301 manufactured by Sumitomo Chemical Co., Ltd.). G: EP copolymer (E polymerization unit / P polymerization unit = 49 /
51 (mass ratio), Esplen 20 manufactured by Sumitomo Chemical Co., Ltd.
1).

H: MT carbon. I: Magnesium oxide (Kyowa Mag # 150 manufactured by Kyowa Chemical Industry Co., Ltd.). J: Calcium hydroxide (Calvit manufactured by Omi Chemical Co., Ltd.). K: α, α'-bis (t-butylperoxy) -p-diisopropylbenzene, Percadox 14 manufactured by Kayaku Akzo. L: triallyl isocyanurate.

[0029]

The fluorinated elastic copolymer composition of the present invention has a vulcanized product having oil resistance, chemical resistance, heat resistance, weather resistance,
In addition to having excellent surface properties, it has the effect of being excellent in water resistance, hot water resistance and steam resistance.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 BB111 BB152 BD121 BD141 BD151 BD161 BE041 EK026 EK036 EK046 EK056 EK066 FD010 FD150 GJ02 GM00

Claims (3)

[Claims] 1. An ethylene copolymer comprising (a) a fluorine-containing elastic copolymer and (b) a polymerizable unit of ethylene / propylene / non-conjugated diene having a mass ratio of 45 to 75/10 to 53/2 to 15 by mass. It contains a propylene-nonconjugated diene copolymer and (c) an organic peroxide, and 1 to 50 parts of the component (b) and 0.3 to 10 parts of the component (c) per 100 parts of the component (a).
A fluorinated elastic copolymer composition comprising: 2. The fluorinated elastic copolymer composition according to claim 1, which contains 6 to 40 parts of the component (b) with respect to 100 parts of the component (a). 3. A vulcanizate obtained by vulcanizing the fluorinated elastic copolymer composition according to claim 1 or 2.