JP2003096249A - Flow property and extrudability improving masterbatch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition, which, when used as a rubber chemical masterbatch in the form of a solid state containing an alkoxysilane compound, particularly of rubbery pellets or rubbery sheets, can prevent the alkoxysilane compound from sticking to the wall of a kneader, improve the handling capability of weighting the alkoxysilane compound, and prevent the bleeding of the alkoxysilane compound from the masterbatch. SOLUTION: The composition comprises (A) a rubber formed by the copolymerization of ethylene, a 3-20C α-olefin, and optinally a non-conjugated polyene, (B) a filler for rubber having a DBP absorption of 100 ml/100 g or more, and (C) an alkoxysilane compound represented by formula (I) [R is a 1-10C, alkyl, R<1> is a 1-4C alkyl or a phenyl, n is 0, 1 or 2, R<2> is a 1-6C, divalent, linear or branched hydrocarbon, R<3> is a 6-12C arylene, m and p are each 0 or 1 with the both not taking 0 at the same time, q is 1 or 2, B is -SCH or -SH when q is 1, and B is -Sx- when q is 2 (x is an integer of 2-8)]. Further, the ratio by weight of (C) to (B) ((C)/(B)) is in the range of 15-0.6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a masterbatch that improves the flowability and extrudability of a rubber material, and more specifically, a masterbatch containing a specific silane coupling agent, which is a compound after kneading. The present invention relates to a masterbatch of a fluidity / extrudability improver having a small viscosity change.

[0002]

2. Description of the Related Art Ethylene / α-olefin / non-conjugated polyene copolymers such as ethylene / propylene / diene copolymer (EPDM) have excellent weather resistance, heat resistance and ozone resistance, and are suitable for automobiles and home appliances. It is often used as a seal part for products and as a filling material. These products are products obtained by a continuous rubber extrusion method.

A rubber composition for extrusion is required to be continuously feedable to an extruder, and a ribbon-shaped compound which is preformed before extrusion does not crack or break during storage and is torn. It is necessary not to. Further, it is required that the extrusion cross section does not change during extrusion molding, that is, the die swell ratio does not change. If the die swell ratio changes, the cross-sectional shape of the glass run product or the window frame product changes, and the sealing performance of the product may deteriorate, which may make it impossible to commercialize.

In addition to this, in the extruded product in which EPDM is mixed with a rubber filler such as carbon black, foreign substances whose cause is unknown are often generated. To investigate the cause,
Even if the foreign matter portion is analyzed, it is often the result that the foreign matter portion is composed of the same material as the rubber base material. This may be resolved spontaneously after a while, and a mysterious phenomenon such as the occurrence of a similar problem at a certain time may occur.

For example, when carbon black is blended as a rubber filler, the shearing energy due to kneading disperses the carbon black in the polymer and at the same time forms a physical bonding layer of carbon gel. It is said that the carbon black composite exhibits excellent mechanical strength. However, at the same time, when the phenomenon of tearing off the polymer molecules adsorbed on the carbon black particles occurs, the radicals generated there chemically bond with each other, showing a completely different property from the carbon gel described above, and a hard, brittle compound. Become. When this phenomenon occurs in molding an extruded product, the above-mentioned problems occur. In order to solve such a problem, Japanese Patent Application Laid-Open No. 7-138379 discloses
It is disclosed that a polysulfide compound is blended for the purpose of capturing radicals such as sulfur and sulfur compounds.

However, in the kneader, these sulfur or sulfur compound was added in an amount of 1.0 × 10 ^-2 per 100 g of the polymer.
When the amount is about mol, there is a problem that a cross-linking reaction starts due to the presence of zinc oxide (ZnO) blended in the blend, resulting in gel (burning / chemical). If about 1.0 × 10 ⁻³ mol, which is 1/10 of the amount, is blended, there is no risk of burns in the kneading machine, but since the amount is too small, it is sufficient around the blended carbon black. There was a problem that it was not dispersed and could not serve the purpose. That is, there has been a demand for a rubber chemical that effectively disperses a radical scavenger around carbon black in which radicals are generated.

The present inventors have found that the alkoxysilane compound has a high affinity with the active groups (-OH, -H, -CO-, -COOH) on the surface of carbon black, such as the alkoxy groups contained in the compound. It was discovered that they disperse (deploy) quickly and have the effect of trapping these radicals. However, since this alkoxysilane compound is a liquid, when it is put into a large kneading machine, it may adhere to the outer wall of the kneading machine by the time it reaches the charging port or the part being kneaded, and carbon black / polymer may be mixed. There was a problem that the specified amount could not be added to the important location. Further, even in the rubber weighing step, it is difficult to weigh the liquid, which is a mode to be shunned. There has been a demand for a material that can be carried to the kneading machine where the alkoxysilane compound does not adhere to the outer wall of the kneading machine.

[0008]

The object of the present invention resides in a rubber chemical masterbatch of a solid state, particularly a rubber-like pellet, a rubber-like sheet containing an alkoxysilane compound,
The masterbatch has good weighability in the rubber weighing process,
There is no bleeding of the alkoxysilane compound, sheets and pellets do not stick to each other, and the masterbatch thereof exhibits an effect corresponding to the blending amount of the alkoxysilane compound and is incorporated into the kneaded product as a masterbatch. In this case, the ribbon-like compound is not cracked or torn without itself becoming a foreign substance and is dispersed in a short time and prepared before being fed to the rubber extruder which is the original purpose of using the compound. Not again
It is possible to obtain an extruded rubber product with a stable extruded cross-sectional shape, and even when molding a molded product, there is no tearing of the ribbon during injection molding, excellent fluidity in the mold, good mechanical properties and good compression set. It is to provide a masterbatch that enables a product to be surely obtained.

[0009]

The present invention includes the following inventions. (1) A rubber (A) obtained by copolymerizing ethylene, an α-olefin having 3 to 20 carbon atoms, and a non-conjugated polyene as necessary, and a rubber filler (B having a DBP oil absorption of 100 ml / 100 g or more). ) And the following formula (I):

[Chemical 2] [In the formula, R represents an alkyl group having 1 to 10 carbon atoms, and R ¹
Is an alkyl group having 1 to 4 carbon atoms or a phenyl group, and n
Is 0, 1 or 2, R ² is a divalent linear or branched hydrocarbon group having 1 to 6 carbon atoms, and R ³ is 6 to 6 carbon atoms.
12 are arylene groups, m and p are 0 or 1 respectively, and m and p are not 0 at the same time, q is 1 or 2, and B is q 1 When-S
It is CN or -SH, and when q is 2, it is -Sx- (in the formula, x is an integer of 2 to 8). ] The composition which consists of the alkoxysilane compound (C) shown by these, Comprising: The weight ratio ((C) / (B)) of (C) and (B) is in the range of 1.5-0.6. A composition comprising: (2) The nitrogen adsorption specific surface area of the rubber filler (B) is 20 to 1
The composition according to (1) above, wherein the composition is 50 m ² / g. (3) The composition according to (1) or (2), wherein the rubber filler (B) is carbon black. (4) The composition according to any one of (1) to (3) above, wherein the total amount of (B) and (C) is 200 to 1100 parts by weight with respect to 100 parts by weight of the rubber (A). (5) The rubber / (A) has an ethylene / α-olefin ratio (molar ratio) of 60/40 to 80/20 and an intrinsic viscosity [η] of 2.5 to 7.0 dl / g. 1) ~
The composition according to any one of (4). (6) Further, a simple substance and / or a compound (excluding an alkoxysilane compound represented by the above formula (I)) consisting of an element of Group 6 of the periodic table (excluding oxygen), and an antioxidant. 1 in total for at least one selected from
The composition according to any one of (1) to (5), which contains 0% by weight or less.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The composition of the present invention comprises ethylene and
A rubber (A) obtained by copolymerizing an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene as necessary, and DBP
Rubber filler (B) with oil absorption of 100 ml / 100 g or more
And a alkoxysilane compound (C) represented by the above formula (I), wherein the weight ratio ((C) / (B)) of (C) and (B) is 1.5 to. It is characterized by being in the range of 0.6. The composition of the present invention can be used as a masterbatch for improving the flowability and extrudability of a rubber material.

[Ethylene / α-olefin Copolymer Rubber (A)] The ethylene / α-olefin copolymer rubber (A) used in the present invention comprises ethylene and an α-olefin having 3 to 20 carbon atoms. A rubber obtained by copolymerizing with a non-conjugated polyene as necessary, preferably a random copolymer, and having the following characteristics is preferable.

(I) Molar ratio of ethylene and α-olefin having 3 to 20 carbon atoms (ethylene / α-olefin) The ethylene / α-olefin copolymer rubber (A) is
(A) a unit derived from ethylene and (b) a carbon number of 3 to 2
A unit derived from an α-olefin of 0 (hereinafter sometimes simply referred to as “α-olefin”) is usually 60/4.
It is contained at a molar ratio [(a) / (b)] of 0 to 80/20, preferably 70/30 to 80/20. When this molar ratio is within the above range, the state (shape) of the masterbatch is stable, and the hardness of the masterbatch is less likely to change with respect to the environmental temperature during kneading. (I) can be quickly dispersed at the carbon black / polymer interface.

(Ii) 13 of intrinsic viscosity ethylene / α-olefin copolymer rubber (A)
The intrinsic viscosity [η] measured in decalin at 5 ° C is 2.5.
~ 7.0 dl / g, preferably 3.5-5.5 dl / g
Is. When the intrinsic viscosity [η] is within the above range, the state in which the alkoxysilane compound (I) is retained in the rubber filler is used as a master batch to retain the shape, and the flexibility,
The dispersibility of the alkoxysilane compound (I) in the compounded filler (carbon black) becomes good.

Specific examples of the α-olefin having 3 to 20 carbon atoms in the ethylene / α-olefin copolymer rubber (A) include propylene, 1-butene, 1-pentene, 1-hexene and 4-. Methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-
Undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-
Heptadecene, 1-octadecene, 1-nonadecene, 1
-Eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene and the like can be mentioned. These α-olefins can be used alone or in combination of two or more. These α
-Of olefins, α-olefins having 3 to 8 carbon atoms,
For example, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene are particularly preferable.

The ethylene / α-olefin copolymer rubber (A) may be copolymerized with a non-conjugated polyene, if necessary, in addition to ethylene and an α-olefin having 3 to 20 carbon atoms. As such a non-conjugated polyene, a cyclic or chain-shaped non-conjugated polyene can be used.

Examples of the cyclic non-conjugated polyene include, for example,
Methyltetrahydroindene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 5-vinyl-2-
Dienes such as norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, dicyclopentadiene, cyclooctadiene, norbornadiene; 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene- Trienes such as 5-norbornene and 2-propenyl-2,5-norbornadiene can be mentioned.

As the chain-like non-conjugated polyene, for example, 1,4-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-
Methyl-1,4-hexadiene, 4,5-dimethyl-
1,4-hexadiene, 6-methyl-1,6-octadiene, 7-methyl-1,6-octadiene, 6-ethyl-1,6-octadiene, 6-propyl-1,6-octadiene, 6-butyl- 1,6-octadiene, 6-methyl-1,6-nonadiene, 7-methyl-1,6-nonadiene, 6-ethyl-1,6-nonadiene, 7-ethyl-1,6-nonadiene, 6-methyl- 1,6-decadiene, 7-methyl-1,6-decadiene, 6-methyl-
Diene such as 1,6-undecadiene and 7-methyl-1,6-octadiene; 4-ethylidene-1,6-octadiene, 4-ethylidene-7-methyl-1,6-octadiene, 4-ethylidene-7-methyl -1,6-nonadiene, 4-ethylidene-6,7-dimethyl-1,6-octadiene, 4-ethylidene-6,7-dimethyl-1,6
-Nonadiene, 4-ethylidene-1,6-decadiene,
4-ethylidene-7-methyl-1,6-decadiene, 4
-Ethylidene-7-methyl-6-propyl-1,6-octadiene, 4-ethylidene-1,7-nonadiene, 4
-Ethylidene-8-methyl-1,7-nonadiene, 4-
Ethylidene-1,7-undecadiene, 4-ethylidene-8-methyl-1,7-undecadiene, 4-ethylidene-7,8-dimethyl-1,7-nonadiene, 4-ethylidene-7,8-dimethyl-1, 7-decadiene, 4-
Ethylidene-7,8-dimethyl-1,7-undecadiene, 7-ethyl-4-ethylidene-8-methyl-1,7
-Undecadiene, 4-ethylidene-7,8-diethyl-1,7-decadiene, 4-ethylidene-9-methyl-
1,8-decadiene, 4-ethylidene-8,9-dimethyl-1,8-decadiene, 4-ethylidene-10-methyl-1,9-undecadiene, 4-ethylidene-9,1
0-dimethyl-1,9-undecadiene, 4-ethylidene-11-methyl-1,10-dodecadiene, 4-ethylidene-10,11-dimethyl-1,10-dodecadiene, 3,7-dimethyl-1,4 Trienes such as 8-decatriene may be mentioned. These non-conjugated polyenes can be used alone or in combination of two or more kinds.

[Rubber Filler (B)] The main rubber filler used in the present invention is carbon black, and if necessary, silica, silicate, clay, talc, light calcium carbonate, heavy One or more kinds of calcium carbonate may be blended.

The rubber filler must hold the alkoxysilane compound (I) in the masterbatch and quickly disperse the compound in the kneader during kneading. Therefore, the nitrogen adsorption specific surface area of the rubber filler is generally 20~250m ² / g, preferably 20~150m ² /
g, more preferably 60 to 120 m ² / g, DB
P oil absorption is 100ml / 100g or more, preferably 15
0 to 600 ml / 100 g, more preferably 300 to 5
It is 00 ml / 100 g. If the nitrogen adsorption specific surface area of the rubber filler exceeds 250 m ² / g, the carbon black used in the master batch will cause the generation of foreign matter in the product, which is not preferable.
When it is less than 0 m ² / g, the alkoxysilane compound bleeds out from the masterbatch, which is not preferable. DBP oil absorption of rubber filler is 100ml / 100g
If it is less than the above range, the alkoxysilane compound will bleed out from the masterbatch, and pellets or sheets cannot be formed.

As carbon black, SRF, GP
F, FEF, MAF, HAF, ISAF, SAF, F
T, MT, etc. can be used. Specific examples of silica include fumed silica and precipitated silica. These rubber fillers may be surface-treated with reactive silanes such as mercaptosilane, aminosilane, hexamethyldisilazane, chlorosilane and alkoxysilane, or low molecular weight siloxane.

[Alkoxysilane compound (C)] The composition of the present invention contains at least an alkoxysilane compound represented by the above formula (I) as an alkoxysilane compound. In the formula (I), examples of the alkyl group having 1 to 10 carbon atoms represented by R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, tert-butyl group,
Examples thereof include a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. Particularly, an alkyl group having 1 to 4 carbon atoms, for example, a methyl group, an ethyl group, an n-propyl group,
Isopropyl group, n-butyl group, isobutyl group, sec-
A butyl group and a tert-butyl group are preferred.

In the above formula (I), the alkyl group having 1 to 4 carbon atoms represented by R ¹ is, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec. -Butyl group and tert-butyl group are mentioned. In the above formula (I), examples of the divalent linear or branched hydrocarbon group having 1 to 6 carbon atoms represented by R ² include, for example, methylene group, dimethylmethylene group, ethylene group, dimethylethylene group, trimethylene. Group, tetramethylene group, 1,2-cyclohexylene group, 1,4-cyclohexylene group, and other alkylene groups; cyclohexylidene group, and other alkylidene groups; diphenylmethylene group, diphenylethylene group, and other arylalkylene groups. . Examples of the arylene group having 6 to 12 carbon atoms represented by R ³ include a phenylene group, a naphthylene group and a biphenylylene group.

The alkoxysilane compound represented by the above formula (I) is a trialkoxysilane compound in which B in the formula is —S ₄ —, for example, bis [3- (trimethoxysilyl) propyl] tetrasulfide [( CH ₃ O) _{3
Si- (CH 2) 3 -S 4} - (CH 2) 3 -Si (OCH 3)
_3], bis [3- (triethoxysilyl) propyl] tetrasulfide _{[(C 2 H 5 O)} 3 Si- (CH 2) 3 -S 4
_{- (CH 2) 3 -Si (} OC 2 H 5) 3], bis [3- (tripropoxysilyl) propyl] tetrasulfide _{[(C 3 H 7 O)} 3 Si- (CH 2) 3 -S 4 - (CH ₂ ) ₃ −
Si (OC ₃ H ₇ ) ₃ ] is preferable, and bis [3- (triethoxysilyl) propyl] tetrasulfide [(C ₂ H _{5
O) 3 Si- (CH 2)} 3 -S 4 - (CH 2) 3 -Si (OC
₂ H ₅ ) ₃ ] is more preferable.

The alkoxysilane compound (C) reduces the rate of change in the apparent activation energy of the compound and suppresses the formation of a physical network that originates from the carbon black / polymer interface generated in the compound during kneading. Have the effect of The formation of this network means that the structure has changed within the compound.

The reason why the alkoxysilane compound (C) exerts the effect of not forming a network is that the alkoxysilane compound has an active species (carboxyl group, lactone, hydroxyl group, ketone group, phenol group) on the surface of carbon black in its chemical structure. It has an alkoxy group that reacts rapidly with the (group), so it covers the surface of carbon black quickly during kneading, and it has a polysulfide group, which is the interface between the carbon black / polymer interface and the carbon black / polymer interface. This is because it has the effect of stabilizing the network formation base point (carbon black / polymer interface) that connects the two.

That is, with a small amount, the alkoxysilane compound is quickly dispersed at the carbon black / polymer interface, which is the location of the cause of viscosity increase that causes processing problems during compound molding, and radicals are trapped at the origin of network formation. Because it does not form a network. Further, the masterbatch of the ethylene / α-olefin copolymer rubber such as EPDM and the rubber filler has an effect of increasing the volume, which also influences the mechanical dispersing force in the kneader, and the rubber filler of the carbon black is added. Dispersion is promoted, and the problem can be reliably solved.

The composition of the present invention comprises an alkoxysilane compound (C) and a rubber filler (B) in that the masterbatch of the present invention maintains the pellet shape and the sheet shape for the purpose of the present invention. Weight ratio ((C) /
(B)) needs to be in the range of 1.5 to 0.6. The weight ratio ((C) / (B)) is 1.2 to 0.7 in terms of preventing bleed-out of the alkoxysilane compound.
Is preferred.

In addition, the composition of the present invention is characterized in that the masterbatch of the present invention retains the pellet shape and the sheet shape for the purpose of the present invention, with respect to 100 parts by weight of the rubber (A) (B). ) And (C) total amount is 200 to 1
The amount is preferably 100 parts by weight, more preferably 400 to 700 parts by weight, and even more preferably 450 to 650 parts by weight. In addition, (B) and (C)
When the total amount of and is 200 parts by weight or more, bleed-out of the alkoxysilane compound can be prevented.

Other Ingredients In the composition of the present invention, if necessary, a simple substance and / or a compound (provided by the above formula (I)) consisting of an element of Group 6 of the periodic table (excluding oxygen) The alkoxysilane compound represented by the formula (1) and the antioxidant can be blended alone or in combination of two or more kinds. The mixing ratio of these components in the composition of the present invention is preferably 10% by weight or less in total in order to maintain a good vulcanization reaction rate.

Examples of the element of Group 6 of the periodic table (excluding oxygen) include sulfur, selenium (selenium), tellurium (tellurium) and polonium chalcogen (oxygen group element). Among the compounds containing the elements of Group 6 of the Periodic Table (excluding oxygen), examples of the sulfur compound include inorganic sulfur compounds such as sulfur chloride and sulfur dichloride; N-cyclohexyl-2-benzothiazole. Sulfenamide (CBS), N-oxydiethylene-2-benzothiazole sulfenamide (OBS), Nt-butyl-2-benzothiazole sulfenamide (BBS), N, N-diisopropyl-
2-benzothiazole sulfenamide, 2-mercaptobenzothiazole (MBT), 2- (2,4-dinitrophenyl) mercaptobenzothiazole, 2- (4-
Morpholinodithio) benzothiazole, 2- (2,6-
Thiazole-based compounds such as diethyl-4-morpholinothio) benzothiazole and dibenzothiazyl disulfide;
Thiourea-based compounds such as thiocarbanilide, diethylthiourea (EUR), dibutylthiourea, trimethylthiourea, diorsotolylthiourea, and ethylenethiourea; tetramethylthiuram monosulfide (TMT)
M), tetramethylthiuram disulfide (TMT
D), tetraethylthiuram disulfide, tetrabutylthiuram disulfide, tetrakis (2-ethylhexyl) thiuram disulfide (TOT), dipentamethylene thiuram tetrasulfide (TRA), and other thiuram-based compounds; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, di Zinc n-butyldithiocarbamate (ZnBDC), zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, tellurium dimethyldithiocarbamate, tellurium diethyldithiocarbamate, and the like; morpholine disulfide , Disulfide compounds such as alkylphenol disulfide; xanthate compounds; average To (II):

[0031]

[Chemical Formula 3] (RO-CS-S-)_n  M^{n +}    (II) (In the formula, R is an alkyl group having 1 to 30 carbon atoms, and n is
Is an integer from 1 to 3, and M ^{n +}Is an n-valent metal ion or an
It is a monium ion. ) Xanthates
Examples include vulcanization accelerators.

If desired, the composition of the present invention may contain a softening agent, a processing aid and an anti-aging agent alone or in combination of two or more kinds. The mixing ratio of these components in the composition of the present invention is preferably 40% by weight or less in total from the viewpoint of assisting the dispersion of the alkoxysilane compound (I) in the carbon black.

As the softening agent, a softening agent usually used for rubber can be used. Specifically, aroma oils, naphthenic oils, lubricating oils, paraffin oils, liquid paraffin, petroleum softeners such as petroleum asphalt, vaseline; coal tar softeners such as coal tar and coal tar pitch; castor oil. Fat oil softeners such as linseed oil, rapeseed oil, soybean oil and coconut oil; tall oil; sub (factis); bees wax, carnauba wax, lanolin and other waxes; ricinoleic acid, palmitic acid, stearic acid, stearic acid Barium, calcium stearate,
Fatty acids and fatty acid salts such as zinc laurate; naphthenic acid;
Pine oil, rosin or its derivatives; synthetic polymer substances such as terpene resin, petroleum resin, atactic polypropylene, coumarone indene resin; ester softeners such as dioctyl phthalate, dioctyl adipate, dioctyl sebacate; microcrystalline wax, liquid Polybutadiene, modified liquid polybutadiene, liquid thiochol,
Examples include hydrocarbon-based synthetic lubricating oils. In consideration of deterioration of the masterbatch and quality stability, paraffinic oil is preferable. The blending amount of these softening agents is appropriately selected within a range that does not impair the object of the present invention, but ethylene.α-
It is generally 50 to 200 parts by weight, preferably 100 to 15 parts by weight, based on 100 parts by weight of the olefin copolymer rubber (A).
0 parts by weight.

As the above-mentioned processing aid, a processing aid used for usual processing of rubber can be used. Specific examples include higher fatty acids such as linoleic acid, ricinoleic acid, stearic acid, palmitic acid, and lauric acid; salts of higher fatty acids such as barium stearate, zinc stearate, and calcium stearate; esters of the above higher fatty acids. To be Examples of the antiaging agent include a sulfur antiaging agent, a phenol antiaging agent, and an amine antiaging agent.

As the sulfur anti-aging agent, the sulfur anti-aging agent usually used for rubber is used. Specific examples of the sulfur anti-aging agent include 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, and 2
-Zinc salt of mercaptomethylbenzimidazole, 2-
Imidazole type anti-aging agents such as zinc salt of mercaptomethylimidazole; dimyristyl thiodipropionate,
Dilauryl thiodipropionate, distearyl thiodipropionate, ditridecyl thiodipropionate,
Examples thereof include aliphatic thioether-based antioxidants such as pentaerythritol-tetrakis (β-lauryl-thiopropionate). Among these, especially 2
-Mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, zinc salt of 2-mercaptomethylbenzimidazole, pentaerythritol-tetrakis (β-
Lauryl-thiopropionate) is preferred.

As the phenol-based antioxidant, a phenol-based antioxidant commonly used in rubber is used.
Specific examples of the phenol anti-aging agent include styrenated phenol, 2,6-di-t-butylphenol,
2,6-di-t-butyl-4-methylphenol, 2,
6-di-t-butyl-4-ethylphenol, 2,4
6-tri-t-butylphenol, butylhydroxyanisole, 1-hydroxy-3-methyl-4-isopropylbenzene, mono-t-butyl-p-cresol, mono-t-butyl-m-cresol, 2,4-dimethyl. −
6-t-butylphenol, butylated bisphenol A, 2,2'-methylene-bis (4-methyl-6-t-)
Butylphenol), 2,2'-methylene-bis (4-
Ethyl-6-t-butylphenol), 2,2'-methylene-bis (4-methyl-6-t-nonylphenol), 2,2'-isobutylidene-bis (4,6-dimethylphenol), 4,4 '. -Butylidene-bis (3-
Methyl-6-t-butylphenol), 4,4'-methylene-bis (2,6-di-t-butylphenol),
2,2'-thio-bis (4-methyl-6-t-butylphenol), 4,4'-thio-bis (3-methyl-6-
t-butylphenol), 4,4'-thio-bis (2-
Methyl-6-butylphenol), 4,4'-thio-bis (6-t-butyl-3-methylphenol), bis (3-methyl-4-hydroxy-5-t-butylbenzene) sulfide, 2,2 '-Thio [diethyl-bis-3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], bis [3,3-bis (4-hydroxy-3-t-butylphenyl) butyric acid] glycol ester, bis [2- (2-hydroxy-5-methyl-3-t]
-Butylbenzene) -4-methyl-6-t-butylphenyl] terephthalate, 1,3,5-tris (3,5-
Di-t-butyl-4-hydroxybenzyl) isocyanurate, N, N′-hexamethylene-bis (3,5-di-t-butyl-4-hydroxyhydrocinnamamide), n-octadecyl 3- (4 -Hydroxy-3,
5-di-t-butylphenyl) propionate, tetrakis [methylene-3- (3,5-di-t-butyl-4-)
Hydroxyphenyl) propionate] methane, pentaerythritol-tetrakis [3- (3,5-di-t-)
Butyl-4-hydroxyphenyl) propionate],
1,1′-bis (4-hydroxyphenyl) cyclohexane, mono (α-methylbenzene) phenol, di (α
-Methylbenzyl) phenol, tri (α-methylbenzyl) phenol, 2,6-bis (2-hydroxy-3)
-T-butyl-5-methylbenzyl) -4-methylphenol, 3,9-bis [2- {3- (3-t-butyl-
4-Hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10
-Tetraoxaspiro [5.5] undecane, 2,5-
Di-t-amylhydroquinone, 2,6-di-t-butyl-α-dimethylamino-p-cresol, 2,5-di-t-butylhydroquinone, 3,5-di-t-butyl-4-hydroxy Diethyl ester of benzyl phosphate,
Examples include catechol and hydroquinone. Examples of particularly preferred phenolic anti-aging agents include 4,4 '
-Butylidene-bis (3-methyl-6-t-butylphenol), 4,4'-methylene-bis (2,6-di-t)
-Butylphenol), 2,2'-thio-bis (4-methyl-6-t-butylphenol), 4,4'-thio-
Bis (3-methyl-6-t-butylphenol), 4,
4'-thio-bis (2-methyl-6-butylphenol), 4,4'-thio-bis (6-t-butyl-3-methylphenol), tetrakis [methylene-3- (3,3.
5-di-t-butyl-4-hydroxyphenyl) propionate] methane, pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 3,9-bis [2] -{3-
(3-t-Butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl]
Examples thereof include −2,4,8,10-tetraoxaspiro [5.5] undecane.

As the amine anti-aging agent, an amine anti-aging agent usually used for rubber is used. Specific examples of the amine-based antioxidant include naphthylamine-based antioxidants such as phenyl-α-naphthylamine and phenyl-β-naphthylamine; p- (p-toluenesulfonylamide) diphenylamine and 4,4′-bis ( α, α-
Dimethylbenzyl) diphenylamine, alkylated diphenylamine, octylated diphenylamine, dioctylated diphenylamine (eg 4,4′-dioctyldiphenylamine), high temperature reaction product of diphenylamine and acetone, low temperature reaction product of diphenylamine and acetone, diphenylamine and A diphenylamine-based antioxidant such as a low-temperature reaction product of aniline and acetone and a reaction product of diphenylamine and diisobutylene;
N, N'-diphenyl-p-phenylenediamine, n-
Isopropyl-N'-phenyl-p-phenylenediamine, N, N'-di-2-naphthyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, N-phenyl-N '-( 3-methacryloyloxy-2-hydroxypropyl) -p-phenylenediamine, N, N'-bis (1-methylheptyl)
-P-phenylenediamine, N, N'-bis (1,4-
Dimethylpentyl) -p-phenylenediamine, N,
N'-bis (1-ethyl-3-methylpentyl) p-phenylenediamine, N- (1,3-dimethylbutyl)-
N'-phenyl-p-phenylenediamine, phenylhexyl-p-phenylenediamine, phenyloctyl-
Examples thereof include p-phenylenediamine antiaging agents such as p-phenylenediamine. Among these, especially 4,
4′-bis (α, α-dimethylbenzyl) diphenylamine, N, N′-diphenyl-p-phenylenediamine and N, N′-di-2-naphthyl-p-phenylenediamine are preferred. In the present invention, the sulfur anti-aging agent, the phenol anti-aging agent and the amine anti-aging agent may be used alone or in combination of two or more kinds.

[Preparation of Masterbatch] The composition of the present invention used as a masterbatch for improving fluidity and extrudability is, for example, a rubber filler (B) such as carbon black and / or other filler and an alkoxysilane compound. (C) is charged into an internal mixer first, the alkoxysilane compound (C) is absorbed in the rubber filler (B) in advance, and then the ethylene / α-olefin copolymer rubber (A) is charged. It can be obtained as a master batch in the form of pellets or sheets by sheeting with a receiving roll or passing through an extruder while cooling. In kneading and sheeting, or in obtaining a pellet-shaped master batch by an extruder, an alkoxysilane compound (C) is used.
In order to prevent the structural change and the decrease in dispersibility in carbon black, the temperature is usually 140 ° C or lower in all steps,
The temperature is preferably controlled to 120 ° C or lower, more preferably 90 ° C or lower.

[Preparation of Rubber Composition and Vulcanized Rubber Molded Product Thereof] The masterbatch of the present invention can be prepared by using an ethylene / α-olefin copolymer using an internal mixer such as a Banbury mixer, a kneader or an intermix. In a kneading process in which carbon black, a processing aid, zinc white, a softening agent, etc. are blended into a polymer rubber as a rubber filler, they are charged into a kneading machine at the same time as the processing aid and zinc white, and the amount to be charged depends on the composition. Although different, it is desirable to add a larger amount of the masterbatch of the present invention to a system containing more carbon black. Normally, carbon black 1
The alkoxysilane compound in the masterbatch is blended in an amount of 0.05 to 6 phr with respect to 00 phr. For example, when the concentration of the alkoxysilane compound in the masterbatch is 50%, carbon black 100p
It is desirable that 0.1 to 12 phr is added to hr. After kneading at a kneading temperature of 80 to 170 ° C. for 2 to 20 minutes, sulfur is used as a roll such as an open roll or a kneader, and if necessary, a vulcanization accelerator, a vulcanization aid, a foaming agent, foaming Add auxiliary agent and roll temperature 40
A rubber composition for extrusion molding and molding can be prepared by kneading at -80 ° C for 5 to 30 minutes and then dispensing.

[0040]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but these do not limit the scope of the present invention in any way. The method of measuring or evaluating the physical properties of the copolymers and the products obtained in Examples and Comparative Examples are
It is as follows. [Intrinsic viscosity [η] measured in decalin at 135 ° C] 1
It was determined by a one-point method using a Fitz-Simons viscometer in decalin at 35 ° C. [Bleed-out property] 50 mm extruder for rubber, diameter 8
A round master die having a diameter of mm was used to extrude into a rod shape at a speed of 2 m / min and cut into lengths of 20 mm to prepare pellet-shaped master batches.

A piece of high-quality paper is cut into 100 mm × 100 mm, 5 pieces of the above chip master batch are placed on this paper, and it is further sandwiched with high-quality paper, and a polyethylene plate (20
g) so that the weight of 80g is evenly applied, and 1
After 0 minutes, the amount of the alkoxysilane compound (C) exuded on the lower surface paper was sensory evaluated. 5 points: No exudation at all. 4 points: Presence thereof is slightly recognized. 3 points: Existence is recognized in some places. 2 points: All areas in contact with the pellets are exuded. 1 point: Exudates in a large amount beyond the area where the pellets are in contact.

[Pellet Collectability] A 50 mm extruder for rubber was used to extrude into a rod shape at a speed of 2 m / min using a round die having a diameter of 8 mm, and cut into lengths of 20 mm to prepare pellet master batches. Then, the pellet shape was evaluated. Good: The pellet shape immediately after extrusion is maintained. Poor: The shape of the pellet immediately after extrusion collapses or is not retained.

[Sheet moldability] Head temperature is 75 ° C., mouthpiece width is 20 mm, thickness is 10 mm in a rubber 50 mm extruder.
At 3 m / min, cut into 30 cm, and immediately hold both ends for 1 minute with both hands to evaluate whether or not the shape was retained according to the following criteria. 5 points: The shape of the extruded sheet is maintained, and there are no cracks due to its own weight and cracks due to extrusion. 4 points: The shape of the extruded sheet is maintained, and there are only a few cracks due to its own weight and cracks due to extrusion. : The shape of the extruded sheet is maintained, but there are many cracks due to its own weight and cracks due to the extrusion. 2 points: The shape of the extruded sheet is not maintained. The state of falling from both hands. 1 point: The extruded material does not have the shape of the die, but is in the form of powder or the alkoxysilane compound and other materials are separated.

[Tensile test] JIS K6251 (199
7 years), measurement temperature 23 ℃, pulling speed 500mm
A tensile test was performed under the condition of / min, and a compound was obtained by using a 150-ton press at 170 ° C for 10 minutes to obtain a vulcanized rubber sheet. The strength T _B at break and the elongation E _B were measured. [Compression set test] JIS K6262 (1997)
A compression set test was conducted according to the above. This test piece is 170
The evaluation condition is 70 ° C.-22.
It's time.

[Ribbon Cracking Test] Width 10 cm × thickness 1.
Cut a 5 cm ribbon compound to a length of 30 cm, fold it in half and fix the ends, leave it in an oven at 40 ° C for 24 hours, then observe the bent surface to check for cracks or cuts. When a crack occurred, the length of the largest crack was measured and recorded. [Extruded product / foreign material evaluation] Ribbon compound 60
mm Extruder, microwave vulcanization tank (UHF)
(200 ° C-3kw) and hot air vulcanization tank (HAV) (23
(0 ° C.) was used in series to obtain a flat plate product at a take-up speed of 7 m / min, and the number of surface foreign matters (foreign matter of 0.03 mm or more) per 1 m was evaluated.

[Workability] (1) Presence or absence of adherence to the wall leading from the input port of the kneading machine to the kneading place with the kneading blades From the center of the input port of the 16-liter Banbury mixer,
The masterbatch, or only the alkoxysilane compound as the main component of the masterbatch (liquid) was charged, and it was evaluated whether or not it adhered to the kneader wall. The evaluation was carried out by judging whether or not the alkoxysilane compound was observed within the range that can be visually confirmed when the floating weight was taken down after the charging and immediately raised. (2) Weighability Workability in weighing the blended amount was evaluated according to the following criteria. 3 points: When weighing to one decimal place, the desired amount can be immediately prepared with a weighing spatula or scissors. 2 points: When weighing up to one decimal place, the shape is likely to collapse, so the desired amount cannot be immediately prepared with a weighing spatula or scissors. 1 point: Since it is in a liquid state and adheres to the weighing cup, it is impossible to accurately weigh the amount of the added chemicals up to the decimal point.

The components used in Examples and Comparative Examples are as follows. Ethylene / α-olefin copolymer rubber (1) Ethylene / propylene / 5-ethylidene-2-norbornene random copolymer (EPT-1): molar ratio of units derived from ethylene and units derived from propylene ( Ethylene / propylene) 78/22, intrinsic viscosity [η] 4.5 dl / g measured in decalin at 135 ° C.,
Iodine number 12 (2) Ethylene / propylene copolymer (EPT-2):
Molar ratio of units derived from ethylene and units derived from propylene (ethylene / propylene) 70/30, 1
Intrinsic viscosity [η] 2.7d measured in decalin at 35 ° C
1 / g, iodine value 0 alkoxysilane compound Bis [3- (triethoxysilyl) propyl] tetrasulfide [manufactured by Degussa Hüls, trade name Si-69] rubber filler

[0048]

[Table 1] * 1 Product name of Asahi Carbon Co., Ltd.

(Examples 1 to 5 and Comparative Examples 1 to 5) (1) Preparation of masterbatch The rubber filler and the alkoxysilane compound were first charged into a kneader ruder (manufactured by Kasamatsu Kakoken Co., Ltd.) to prepare carbon black in advance. The alkoxysilane compound was absorbed, and then the polymer was charged and kneaded for 3 minutes (filling rate 75%, kneading temperature 72 ° C.). After that, let it pass through a single screw extruder and have a diameter of 2 m.
A pellet-shaped masterbatch having a length of m and a length of 18 mm was obtained. The temperature of the extruder was controlled at 75 ° C while cooling with water.

(2) Formulation for confirming the effect of improving processability 100 parts by weight of the masterbatch prepared in the above (1), 100 parts by weight of Mitsui EPT3090E as a polymer (weight after oil extension 110 parts by weight), SRF-H carbon black ( Asahi Carbon Co., Ltd., trade name: Asahi # 50HG 90 parts by weight, paraffin oil (made by Idemitsu Kosan Co., Ltd., trade name: Diana Process PW-380) 70 parts by weight, zinc flower (Sakai Chemical Industry Co., Ltd. ), Trade name: No. 1) 5 parts by weight and 1 part by weight of stearic acid were put into a Banbury mixer having a capacity of 16 liters (manufactured by Kobe Steel, Ltd.) and kneaded.

This kneading was carried out by a method of adding all the components at once with a filling rate of 70%. The kneading temperature was 145 ° C. when the compound was discharged. 2 after adding all the ingredients
After kneading for a minute, the floating weight was raised to clean the kneaded material, and the kneading was continued for another 2 minutes, and the kneaded material was discharged to a receiving roll of 14 inches. After that, the compound temperature is 7
After confirming that the temperature became 0 ° C. or lower, a vulcanizing agent and a vulcanization accelerator were added, and a test piece for ribbon cracking test and extruded product / foreign matter evaluation was prepared.

Using the obtained compound, a test piece was prepared by the method described in JIS, and a tensile test and a compression set test were conducted according to the above-mentioned methods. Further, a ribbon cracking test and extruded product / foreign matter evaluation were conducted according to the above-mentioned methods. In addition, Comparative Examples 1 to 3 show that when the DBP oil absorption of the rubber filler (carbon black) is too low, it is difficult to prevent the bleed-out of the alkoxysilane compound and form a sheet.

Comparative Example 4 is an example in which the alkoxysilane compound, which is the main component of the masterbatch, was used as it was (liquid), and the amount of the alkoxysilane compound charged did not reach the kneading place. Therefore, the processability and extrudability improving effect originally possessed by the alkoxysilane compound cannot be exhibited.

Comparative Example 5 is an example in which the masterbatch of the present invention was not compounded in the compounding composition for confirming the processability improving effect. If this compounding composition was not compounded, the extruded product (bugs) would increase and the obtained product would be obtained. A compound compound ribbon is an example of ribbon cracking. The results are shown in Table 2.

[0055]

[Table 2] In Table 2, "oil" means paraffinic oil (manufactured by Idemitsu Kosan Co., Ltd., trade name: Diana Process PW-38).
0), which is added as a processing aid or a flexibility-imparting agent at the time of preparing a masterbatch.

[0056]

INDUSTRIAL APPLICABILITY The composition of the present invention is used as a rubber chemical masterbatch of a solid state containing an alkoxysilane compound, particularly a rubber-like pellet or a rubber-like sheet,
Prevents adhesion of alkoxysilane compounds to the walls of kneading machines,
It is possible to improve the weighing performance of alkoxysilane compounds,
Further, bleed-out of the alkoxysilane compound from the masterbatch can be prevented.

Continued front page    (72) Inventor Masaaki Kawasaki             3 Chikusaigan, Ichihara, Chiba Prefecture Mitsui Chemicals Stock Association             In-house F-term (reference) 4F070 AA13 AA16 AB16 AC04 AC53                       AD03 FA01 FA14 FB06 FC05                 4J002 BB051 BB151 DA036 FA096                       FB096 FD016

Claims (6)

[Claims] 1. A rubber (A) obtained by copolymerizing ethylene, an α-olefin having 3 to 20 carbon atoms, and optionally a non-conjugated polyene, and a DBP oil absorption of 100 ml / 100.
g or more of rubber filler (B) and the following formula (I): [In the formula, R represents an alkyl group having 1 to 10 carbon atoms, and R ¹
Is an alkyl group having 1 to 4 carbon atoms or a phenyl group, and n
Is 0, 1 or 2, R ² is a divalent linear or branched hydrocarbon group having 1 to 6 carbon atoms, and R ³ is 6 to 6 carbon atoms.
12 are arylene groups, m and p are 0 or 1 respectively, and m and p are not 0 at the same time, q is 1 or 2, and B is q 1 When-S
It is CN or -SH, and when q is 2, it is -Sx- (in the formula, x is an integer of 2 to 8). ] The composition which consists of the alkoxysilane compound (C) shown by these, Comprising: The weight ratio ((C) / (B)) of (C) and (B) is in the range of 1.5-0.6. A composition comprising: 2. The composition according to claim 1, wherein the rubber filler (B) has a nitrogen adsorption specific surface area of 20 to 150 m ² / g. 3. The composition according to claim 1, wherein the rubber filler (B) is carbon black. 4. With respect to 100 parts by weight of the rubber (A),
The composition according to claim 1, wherein the total amount of (B) and (C) is 200 to 1100 parts by weight. 5. The rubber (A) has an ethylene / α-olefin ratio (molar ratio) of 60/40 to 80/20, and
The composition according to claim 1, which has an intrinsic viscosity [η] of 2.5 to 7.0 dl / g. 6. A simple substance and / or a compound (excluding an alkoxysilane compound represented by the above formula (I)) composed of an element of Group 6 of the periodic table (excluding oxygen), and aging. The composition according to any one of claims 1 to 5, which contains a total of 10% by weight or less of at least one selected from inhibitors.