JPS61195142A - Vulcanizable halogenated ethylene-alpha-olefin copolymer rubber composition - Google Patents

Abstract

PURPOSE:The titled composition having improved resistance to gasoline without damaging improved roll processing properties, obtained by blending halogenated ethylene.alpha-olefin copolymer rubber with epichlorohydrin rubber in a specific blending ratio. CONSTITUTION:(A) A halogenated ethylene.alpha-olefin copolymer rubber containing 15-40wt%, preferably 20-35wt% halogen obtained by pulvering copolymer rubber of ethylene and 3-10C alpha-olefin, containing 3-30 shown by iodine value of polyene component, making it into an aqueous dispersion state, and bringing it into contact with molecular chlorine or bromine at 70-90 deg.C, is blended with preferably a hydrochloric acid absorbent, an atioxidant, and a metallic deactivator, and blended with (B) epichlorohydrin rubber in a weight ratio of the component A to B of A/B=95/5-10/90, preferably 80/20-40/60, and further mixed with a filler, a softening agent, a vulcanizing agent, etc., approprivately.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vulcanizable 10-genated ethylene/α-olefin copolymer rubber composition, and more particularly to a vulcanizable 10-genated ethylene/α-olefin valve type rubber composition. This invention relates to a vulcanizable chlorogenated ethylene/α-olefin copolymer rubber composition with improved gasoline properties.

Technical background Is halogenated ethylene/α-olefin copolymer comb an ethylene ψα-olefin copolymer comb? - It has been given oil resistance, adhesion, and flame retardancy by chlorination, and has excellent heat aging resistance and roll processability like ethylene/α-olefin copolymer rubber.However, it has gasoline resistance. On the other hand, epichlorohydrin rubber, which is a typical oil-resistant rubber, has excellent gasoline resistance, but it is highly sticky and may cause damage to the mixing roll or Banbury interior when wires are mixed. It has the disadvantage that it is very difficult to knead because it sticks strongly to other materials.

OBJECTS OF THE INVENTION An object of the present invention is to provide a vulcanizable rubber composition with improved gasoline resistance without impairing the excellent roll processability of halogenated ethylene/α-olefin copolymer rubber.

Structure of the Invention According to the present invention, the halogenated ethylene/α-olefin copolymer rubber (A) and the epichlorohydrin rubber (B) have a ratio of A/5=9515 to 10/90, preferably K/
A vulcanizable halogenated ethylene/α-olefin copolymer rubber composition is provided which is blended in a weight ratio of B=80/20 to 40/30.

Preferred embodiments of the invention The epichlorohydrin rubber used in the present invention includes epichlorohydrin polymer rubber, epichlorohydrin/ethylene oxide copolymer rubber, epichlorohydrin/allyl glycidyl ether copolymer rubber, and/or epichlorohydrin/ethylene oxide/allyl glycidyl ether terpolymer rubber. show.

Halogenated ethylene, which is component (A) of the composition of the present invention.
The chlorine or bromine content of α-olefin copolymer rubber is 15
~40wt%, preferably 20-65wt4N-%
It is. If the oil content is too small, the desired oil resistance cannot be obtained, while if it is too large,
This results in the disadvantage that the cold resistance and processability of the composition of the present invention are impaired.

Halogenated ethylene α-olefin copolymer rubber 1) Ethylene α-olefin copolymer rubber, which is the base polymer of the polymer, includes ethylene and α-olefin, such as propylene, 1-butene, 1-pentene, 1-hexene, 4- A copolymer of methyl-1-pentene, 1-octene, 1-decene, etc., with a molar ratio of ethylene and α-olefin of about 50150 to 9515 or a Mooney viscosity ML
1+4 (100C) is about 10-150, preferably about 2
Books from 0 to 80 are used.

The above chlorinated rubber is usually produced as follows.

To chlorinate mass, ethylene/α-olefin/copolymer rubber, the copolymer rubber is pulverized into fine particles, the fine particles are made into an aqueous dispersion state, and then molecular chlorine is added at a temperature of usually about 70 to 90C. The copolymer rubber may be dissolved in a chlorine-stable solvent such as carbon tetrachloride or tetrachlorethylene, and the copolymer rubber may be brought into contact with molecular chlorine in a homogeneous solution state.

In addition, when chlorinating using molecular chlorine,
According to conventional knowledge, the chlorination reaction rate can be significantly increased by light irradiation.

Treatment after the chlorination reaction is usually carried out as follows.

In the case of chlorination in aqueous dispersion, the chlorinated rubber is separated from the molecular chlorine by washing with water and dried. In the case of chlorination in a solution state, the reactive solution is poured into a poor solvent for chlorinated rubber, such as excess methanol, and the precipitate is collected, washed with this solvent, and then dried.

In order to adjust the degree of chlorination, the amount of molecular chlorine and other chlorinating agents used, reaction time, reaction temperature, etc. may be appropriately selected. The chlorine content is usually around 15-4 at this stage.
It is advisable to adjust the amount to 0 tlN-1, preferably about 20 to 65% by weight.

If molecular bromine is used instead of molecular chlorine, it is natural that brominated rubber will be produced in the same way.These halogenated rubbers are treated with a hydrochloric acid absorbent, an antioxidant, and a metal deactivator, respectively. It is preferable to add about 0.05 to 2 parts by weight per 100 parts by weight of the a-genated rubber. .

Examples of hydrochloric acid absorbents include organic acid salts of Group 4 metals of the periodic table, such as magnesium stearate, calcium stearate, manacea sotho, noidrotalcite, epoxidized soybean oil, and epoxy-based hydrochloric acid absorbents. Examples of the agent include di-t-butylhydroxytoluene, tetrakis[methylene(3,5-di-t-butyl-4-hydroxy)hydrocinnamate comethane, d,t-α-tocopherol, phenyl-β-naphthylamine, Triphenylmethane, 1,4-benzoquinone, metal deactivators include tris(nonylphenyl)phosphite, isopropyl citrate, pentaerythritol,
Tetrakis(2,4-di-butylphenyl)-4,
Examples include 4'-biphenylene di-phosphite.

These exhibit remarkable effects on hue stabilization and gelation prevention of halogenated rubber.

In the present invention, the use of halogenated ethylene/α-olefin copolymer rubber (A) and epichlorohydrin rubber (B) in combination is important in terms of achieving the objective. (, () provides good rollability without excessive stickiness for unvulcanized formulations, and epichlorohydrin rubber provides gasoline resistance for vulcanized products.

Halogenated ethylene/α-olefin copolymer rubber (A)
The blending ratio of and epichlorohydrin rubber (B) can be arbitrarily selected depending on the use of the composition of the present invention, but the weight ratio is usually A/B = 9515 to 10/90, preferably A/B = 80/ 20 to 40/30. If the ratio of epichlorohydrin rubber (B) is too small, the original purpose of improving gasoline resistance cannot be achieved, and if it is too large, the excellent characteristics of the halogenated ethylene/α-olefin copolymer rubber will not be achieved. A problem arises in that certain good roll processability is impaired.

When obtaining a vulcanizate from the composition of the present invention, the halogenated ethylene/α-olefin co-i rubber (A) and epichlorohydrin rubber (B) may be used depending on the intended use of the vulcanizate and its performance. In addition, the types and amounts of reinforcing agents, fillers, and softeners for rubber, the types and amounts of compounds constituting the vulcanization system such as vulcanizing agents, vulcanization accelerators, and vulcanization aids, and the vulcanizate. The process for manufacturing is selected as appropriate.

In the present invention, halogenated ethylene α
-Olefin copolymer rubber (A),! :Epichlorohydrin rubber<B) The total amount is appropriately selected depending on the performance and intended use of the vulcanizate, but is usually 20% by weight or more, preferably 25% by weight or more.

The softening agent that can be used in the present invention is usually a softening agent used for rubber, but examples include process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, petroleum softeners such as petrolatum, coal tar, coal tar, etc. Pitch nanocol tar-based softeners, fatty oil-based softeners such as castor oil, linseed oil, rapeseed oil, coconut oil, tall oil;
Sub: Waxes such as beeswax, carnauba wax, and lanolin; Fatty acids and fatty acid salts such as ricinoleic acid, palmitic acid, barium stearate, calcium stearate, and zinc laurate: Petroleum resin, atactic polypropylene, coumaron indene resin, polyester-based Examples include synthetic polymer substances such as resins, ester plasticizers such as dioctyl adipate and dioctyl phthalate, microcrystalline waxes, and sub(factice).

The blending amount of these softeners can be appropriately selected depending on the use of the vulcanizate; It is usually added in a maximum of 100 parts by weight, preferably a maximum of 70 parts by weight.

In the present invention, SRF, PF, FEF, and HAF are used.

Carbon blacks such as 15AF, SAF, FT, MT and rubber reinforcing agents such as finely divided silicic acid and fillers such as light calcium carbonate, ground calcium carbonate, talc, clay, etc. may be used.

The type and amount of these rubber reinforcing agents and fillers are appropriately selected depending on their use, but usually at most 300 parts by weight per 100 parts by weight of the total amount of rubber (A) and epichlorohydrin rubber (B). , preferably at a maximum of 200 parts by weight.

The vulcanizate obtained from the composition of the present invention is normally prepared by preparing an unvulcanized compounded rubber by the method described below in the same way as when general rubber is vulcanized, and then using the compounded rubber as intended. It is manufactured by molding it into a shape and then vulcanizing it.

As a vulcanizing agent, a combination of metal salt, sulfur, vulcanization accelerator,
Combination of metal salt and polyamine, combination of metal salt and sulfur donor, combination of metal salt and polymethylol/phenol resin or brominated polymethylol/phenol resin, combination of metal salt, alkylphenol disulfide, vulcanization accelerator, metal salt, Examples include triazine compounds and combinations of basic substances with a pka of 75 or more.

As the metal salt, magnesia, zinc white, higher fatty acid zinc such as zinc stearate, zinc oleate, red lead, litharge, etc. are used. The metal salt is usually used in an amount of 1 to 15 parts by weight based on 100 parts by weight of the halogenated ethylene/α-olefin copolymer rubber (A) and epichlorohydrin rubber (B). l'i as a vulcanization accelerator
N-cyclohexyl-2-benzothiazole-sulfenamide, N-oxydiethylene 2-benzothiazole-sulfenamide,! V,N-diisopropyl-2
-Benzothiazole sulfenamide, 2-mercaptobenzothiazole, 2-(2,4-dinitrophenyl)
Thiazole series such as mercaptobenzothiazole, 2-(2,6-dinithyl-4-molpolynotio)benzothiazole, dipenzothiazyl-disulfide, etc. Nidiphenylguanidine, triphenylguanidine, diorthotolylguanidine, orthotolyl pi guanide, diphenylguanidine phthalate, etc. Guanidine series; acetaldehyde-aniline reaction product, butyraldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde ammonia, and other aldehyde amines or aldehyde-ammonia series; 2-mercaptoimidacilline and other imidacillin series; thiocarbamate, Thiourea series such as ruthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea: tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide, etc. Thiuram-based zinc dimethyldithiocarbamate, zinc diethylthiocarbamate, zinc di-louptyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate,
Examples include dithioate salts such as selenium dimethyldithiocarbamate and tellurium diethyldithiocarbamate; xanthate salts such as zinc dibutylxanthate; and the like.

The amount of these vulcanization accelerators used is
α-olefin copolymer rubber (A) Total amount of tobichlorohydrin rubber (B) Usually 0.1 per 100 parts by weight
~10 parts by weight are used.

Furthermore, polyamines such as diethylenetriamine and hexamethylenetetramine, thiourea, A/7 Ardoner such as 25-dimercapto-1,3,4-thiadiazole, phenolic resins such as AmheroL S T-137, and Vultac 5, etc. alkylphenol disulfide, 2,4.6-trislicabutose z-)
Triazine compounds such as riazine, dicyclohexylamine, basic substances with a pka of 7.5 or more such as Acting SL, etc. are used as appropriate, and the amount of these used is determined by the amount of halogenated ethylene/α-olefin copolymer rubber (A) and epichlorohydrin. It is usually used in an amount of 0.1 to 8 parts by weight per 100 parts of the total amount of rubber (B).

Further, by using an anti-aging agent, it is possible to extend the material life of the vulcanizate obtained from the composition of the present invention, as in the case of ordinary rubber. The anti-aging agents used in this case include, for example, phenylnaphthylamine, aromatic secondary amines such as N,N'-di-2-naphthyl-ρ-phunicocondiamine, dibutylhydroxytoluene, tetrakis[methylene[3 , 5-di-t-butyl-4-hydroxy[hydrocinnamate]methane and other sterically hindered phenolic stabilizers are used.
The proportion of #i is usually 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the total amount of α-olefin copolymer rubber (A) and tobichlorohydrin rubber (B).

Unvulcanized compounded rubber is usually prepared by the following method.

That is, in a mixer such as a Banbury mixer, halogenated ethylene/α-olefin copolymer rubber (A), epichlorohydrin rubber (B), filler, and softener are mixed at 80%
After kneading for 3 to 10 minutes at a temperature of Z' to 150C, a vulcanizing agent is further mixed using rolls such as an open roll, and the mixture is kneaded for 5 to 3 minutes at a roll temperature of 40 to 80R.
After kneading for 0 minutes, the mixture is separated to prepare a ribbon-like or sheet-like compounded rubber.

The compounded rubber thus prepared is molded into the desired shape using an extruder, calendar roll, press, etc., and at the same time as the molding or the molded product is introduced into a vulcanization tank, usually 1
A vulcanizate can be obtained by heating at a temperature of 30 to 230C, usually for 1 to 30 minutes.

This vulcanization step may be performed using a mold or without a mold.

The vulcanized product produced as described above is useful as an electrical insulating material, automobile industrial parts, and civil engineering and construction materials.As an electrical insulating material, it can be used for plug caps, ignition caps, distributor caps, etc. It is specifically used for caps around automobile engines, condenser caps, cylindrical insulating layers covering the current-carrying parts of electric wires such as marine electric wires and automobile ignition cables, and cable joint covers.

Automotive industry parts include hoses such as radiator hoses and fuel hoses, automotive exterior parts such as bumper hoses, bumper fillers, bumper strips, bumper side guards, overriders, and side protection moldings, various weather strips, boots, and balls. Can be used for joint seals, inner liners for tubeless tires, inner tubes for tires, white sidewalls for tires, various vibration-proofing materials, etc.Also for civil engineering and building materials, roofing sheets, heat-resistant belts,
Used for construction gaskets, 1-way joint seals, etc.

Furthermore, a foaming agent and, if necessary, a foaming aid are added to the rubber compound prior to vulcanization to create a foamed vulcanizate that can be used for heat insulation materials, cushioning materials, sealing materials, soundproofing materials, electrical insulation materials, etc. It is also possible to do this.

Examples of blowing agents include inorganic blowing agents such as hydrogen carbonate, sodium carbonate, ammonium hydrogen carbonate, ammonium carbonate, and ammonium nitrite.
Nitroso compounds such as '-dimethyl-N, N'-dinitrosoterephthalamide, 7V, #'-dinitron pentamethylenetetramine; azodicarbonamide, azobisisobutyronitrile, azocyclohexylnitrile, azodiaminobenzene, azo Azo compounds such as dicarboxylates; benzenesulfonyl hydrazide, toluenesulfonyladazide, p,p'-oxybis(benzenesulfonylhydrazide), diphenylsulfone-
3゜6'-disulfonylhydrazitonatonosulfonylhydrazide compounds; include azide compounds such as calcium azide, 4,4'-diphenyldisulfonyl azide, and P-toluenesulfonyl azide, especially nitroso compounds, azo compounds, and azide compounds. preferred.

These blowing agents are generally blended in a proportion of 0.3 to 30 parts by weight, preferably about 1 to 201 parts by weight, per 100 parts by weight of non-logenated rubber, and generally have an apparent specific gravity of 0.03 to 0.
7 to form a foam.

Next, the present invention will be explained based on examples.

Reference example 1゜Ethylene/1-butene copolymer rubber [ethylene/1-butene molar ratio 92/8, AfLt+q (100C] 30)
5 t was dissolved in 2 t of carbon tetrachloride and charged into a 6 t capacity glass reaction vessel equipped with a stirrer and a thermometer.
While keeping the temperature at 30C and irradiating a 20F daylight color fluorescent lamp from the outside of the vessel, chlorine gas was introduced into the reaction vessel at 209C.
The chlorination reaction was carried out for 70 minutes.

Thereafter, nitrogen gas was passed through the reaction vessel to remove excess chlorine gas.

Add 0.3f of di-t-butylhydroxytoluene to this solution.
, product name Sandstub P-EPQ (manufactured by C Sands) 0.
5? , Product name: MarA273 (manufactured by 7Deforce Arcus Co., Ltd.) 0
．． 3f was added.

Next, this was concentrated using an evaporator, and the solvent was thoroughly removed using a vacuum dryer at room temperature.

The properties of the chlorinated rubber thus obtained were measured as follows.

MLl+* (IODC): JIS [6300, Shimadzu M
5 V-200 Model Munney Viscometer Chlorine content: Bomb combustion method Specific gravity: Toyo Seiki automatic hydrometer measurement results are shown below.

Mooney viscosity 80 Chlorine content 30 tht% Specific gravity 1.1 (1/cc Examples 1 to 5° Chlorinated ethylene/1-butene copolymer rubber [chlorine content 3
Q mtchi, MLx+*C100C) 80, specific gravity 1.10p/cc), epichlorohydrin rubber [trade name Zekron 1) 00 (manufactured by Nippon Zeon Co., Ltd.) #jt+q(1
00'C) 30, specific gravity 1.3jl/CCI, filler in the blending ratio shown in Table 1, and 4.31 Banbury mixer [O
OC type (manufactured by Kobe Steel, Ltd.)] for 6 minutes.

The rubber temperature immediately after dumping was 130C.

Using an 8 x 20 inch open roll,
Additionally mix a vulcanizing agent and a vulcanization accelerator in the proportions shown in Table 1,
The mixture was kneaded for 5 minutes at a roll temperature of 30C to obtain a compounded rubber. At this time, the adhesion of each compounded rubber to the roll was observed at the same time as the crosstalk as a measure of roll processability.

Table 1 Compound rubber
100 Stearic acid Magnesium monoxide 7 HAF carbon black 302-Mercaptobenzimidazole 0.5 Nickel dibutyldithiocarbamate 0.5 Kneaded rubber compound at 130C for 10
Press vulcanized for 30 minutes under pressure of 0 Kf/- to a thickness of 210 mm.
A vulcanized rubber sheet of No. 1 and a cylindrical block of Qinch thickness were prepared.

The obtained 2-Akebono vulcanized rubber sheet and cylindrical block Fi
After being left in a constant temperature room at 251:' for one day, it was subjected to a test.

First, tensile strength, elongation, and hardness were measured based on JIS K6501.
of toluene/isooctane = 70 in a 50150 mixture.
The sample was left to stand for a period of time and the swelling rate was measured.

Comparative Example 1 The same procedure as in Example 1 was repeated except that the rubber component in Example 1 was solely chlorinated ethylene/1-butene copolymer rubber.

Comparative Example 2 In Example 1, the rubber component was replaced with epichlorohydrin rubber [
The procedure was repeated in the same manner as in Example 1, except that the product name was changed to "Zekron 1) 00 (manufactured by Nippon Zeon Co., Ltd.)".

The above measurement results are shown in Table 2.

Claims (4)

[Claims] (1) The weight ratio of halogenated ethylene, α-olefin copolymer rubber (A) and epichlorohydrin rubber (B) is A
A vulcanizable halogenated ethylene/α-olefin copolymer rubber composition, characterized in that /B=95/5 to A/B=10/90. (2) The vulcanizable rubber composition according to claim (1), wherein the halogen content of the halogenated ethylene/α-olefin copolymer rubber (A) is 15 to 40% by weight. (3) A vulcanizable rubber composition according to claim 1 or 2, characterized in that the α-olefin contains 3 to 10 carbon atoms. (4) The vulcanizable rubber composition according to claim 1, wherein the ethylene/α-olefin copolymer rubber before halogenation contains a polyene component having an iodine value of 3 to 30.