JPS6142552A - Rubber composition - Google Patents

Abstract

PURPOSE:To provide a rubber compsn. having improve resilience and tensile strength, consisting of a rubber component contg. a specified rubber polymer and additives. CONSTITUTION:An alkali or alkaline earth metal adduct of an unsaturated rubbery polymer obtd. by polymerizing an unsaturated diene monomer in the presence of an alkali or alkaline earth metal catalyst such as n-butyllithium, is reacted with a compd. contg. a bond of the formula (wherein M is O, S) such as N,N-dimethylformamide to obtain a rubber polymer having a Mooney viscosity of 10-200. Additives such as vulcanizing agent, vulcanizing accelerator, reinforcing agent, filler, etc. are blended with a rubber component contg. not more than 10wt% said rubbery polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention relates to a rubber composition that provides a vulcanized rubber with improved tensile strength and rebound resilience.

Specifically, the alkali metal and/or alkaline earth metal added to the unsaturated f-mu-like polymer-, fJK by polymerization or post-reaction and 10-N'11 in the molecule.
This invention relates to a rubber composition containing, as a rubber component, a rubbery polymer obtained by reacting a compound having a bond (in the formula, M represents 0 atom or SIg).

(Prior art and problems to be solved by the invention) Recently,
From the viewpoints of both low fuel consumption and safety of automobiles, there is a strong demand for a reduction in the rolling resistance of tires and excellent braking performance on wet road surfaces, that is, an improvement in wet skid resistance.

In general, these tire properties are considered to correspond to the dynamic viscoelastic properties of the tread rubber material, and are known to be contradictory properties [for example, Tranaa, c
tion of Engineering, R0 Engineering, Volume 40, 239A-2
56, 1964].

In order to reduce the rolling resistance of a tire, the tread rubber material needs to have high rebound elasticity. Considering all the driving conditions of the car, this rebound elasticity is evaluated at temperatures from 50 degrees Celsius to around 70 degrees Celsius. There is a need.

On the other hand, in order to improve braking performance on wet roads, which is an important performance in terms of vehicle safety, it is necessary to have high wet skid resistance as measured by a Pritish-Bauquepull skid tester, and therefore In this case, it is necessary that the energy loss due to the spring resistance that occurs when the tires are braked and the road surface becomes slippery is large.

Conventionally, in order to satisfy these two contradictory properties, a styrene-butadiene copolymer rubber with a bound styrene content of 20 to 251 n'lA% and a cis-1,4-bond unit of 8% have been used.
Combinations of high-cis 1.4-polybutadiene rubbers with 0 or more fissures have been used, but they are not satisfactory in terms of wet skid resistance. Attempts have been made to improve the resistance, but it is inevitable that the rebound elasticity will be low, and improvements are desired.

(Middle stage for solving the problems) The present inventors solved the above-mentioned drawbacks (as a result of intensive research, an unsaturated polymer obtained by reacting an alkali gold 6-addition unsaturated polymer rubber with benzophenones) A rubber composition containing rubber as a rubber component has significantly improved anti-shock elasticity without changing wet skid resistance, compared to a case where the same -Of,dfON composite rubber is used and is not reacted with benzophenones. I discovered something that could be improved (Japanese Patent Application Laid-open No. 5
8-189203) 0 Furthermore, as a result of repeated studies, the present inventors found that instead of benzophenones, 10 -kT bonds (in the formula, M is 0) were added in the molecule.
The present invention was completed based on the discovery that the use of all compounds having a sulfur atom (representing a sulfur atom or an S atom) similarly improves the anti-irradiation elasticity and further improves the tensile strength.

Wood brother! By carrying out I4, taking tires as an example, it is possible to obtain a composition that harmonizes at a high level the transfer resistance and braking performance on wet road surfaces, that is, wet skid resistance, which are important in recent tire performance mentioned above. For example, if the above compound is introduced into a styrene-butadiene copolymer rubber with a bound styrene content of 20 to 25 M firewood % so that the wet skid resistance satisfies the water requirement, the rubber will warp without impairing the wet skid resistance. Elasticity fi: Since it can be significantly improved, it is possible to obtain a composition that can improve the above two properties and satisfy the above two properties using the rubber alone. In addition, cis1, which has high rebound elasticity,
, 4-If all of the above compounds are introduced into polybutadiene rubber having 80 or more bonding units, the wet skid resistance of this rubber is at a sufficient level, but the rebound elasticity is low, and the bonded styrene bones have a mass of 50M. By combining the above styrene-butadiene copolymer rubber, a composition can be obtained which can satisfy the above two properties in aquatic plants.

Conversely, in combination with a styrene-butadiene rubber containing 30 g fiz % or more of bound styrene gold, a composition is obtained which similarly satisfies both properties with high water 4r5.

Furthermore, the above compound is added to both a polybutadiene rubber having 80 or more cis-1,4-bond units and a styrene-butadiene copolymer rubber having a bound styrene content of 30% or more.
If I:s are combined, a composition that can satisfy both properties at a higher level can be obtained.

Furthermore, the composition of the present invention is not particularly required to have high wet skid resistance, but can be used even when high rebound resilience is required.

The rubber composition comprising the rubber component and the compounding agent of the present invention is bonded with an alkali metal and/or alkaline earth metal-added unsaturated rubbery polymer in the molecule at 10 M (where M is 0 atom or S atom). A rubber composition containing a small amount (in total, 10% by weight) of an unsaturated rubbery polymer in which the compound is introduced into the molecule by pre-reacting with a compound having two
By using this composition, it is possible to improve the overall resilience without compromising tensile strength and wet skid resistance.

The unsaturated rubbery polymer in which the compound used in the present invention is contained in the molecular chain is polymerized by a polymerization method (solution polymerization, emulsion polymerization, etc.)
diene polymers and copolymers such as butadiene, ingrene, 1,6-pentadiene, etc., containing carbon-carbon double bonds in the polymer chain regardless of the These include ring-opened (co)polymers.

Specifically, polybutadiene rubber, polyisoprene rubber, polyisoprene rubber, styrene-butadiene copolymer rubber (usually bound styrene is 50 or less), styrene-imprene copolymer rubber (usually bound styrene is 50 or less) weight% or less), getadiene-imprene copolymer rubber, acrylonitrile-butatsuene copolymer rubber1. + Solved entasoene rubber, getatsuene-piperylene copolymer rubber, getatsuene-propylene copolymer rubber, polybentenamer 1,
Examples include IP +3 octenamer, cyclobentene-socyclopentadiene ring-opening copolymer rubber, but are not particularly limited thereto. Furthermore, there is no particular restriction on the ξ-cro groove structure of the diene units in the polymer.

The compound having -C-N-; bond +1 (in the formula, M represents an O atom or an S atom) in the molecule used in the present invention is a compound disclosed in Japanese Patent Application No. 58-249101.
Specifically, N,N-dimethylformamide, N,N-
Noethylformamide; N,N-diethylacetamide P; aminoacetamide, N,N-diN-7enylsoacetamide; N,N-trimethylacrylamide, N,
N-tumethylmethacrylamide; 4-pyridylamide,
N,N-dimethyl-4-pyridylamide; N,N-dimethylbenzamide, p-aminobenzamide, NZ
, N/-(p-dimethylamino)benzamide,
N, N-dimethyl-N'-(p-ethylamino)benzamide, N-acetyl-N-2-naphthylbenzamide: succinic acid amide, maleic amide, N, N, N',
N'-tetramethylmaleic enzyme amide; succinimide,
Maleimide, N-methylmaleimide, N-methylphthalimide, 1,2-cyclohexanedicarboximide, N
-Methyl-1,2-cyclohexanedicargoximide;
Oxamide, 2-furamide, N, N, N', N'-
Tetramethyloxamide, N,N-dimethyl-2-furamide; N,N-dimethyl-8-quinolinecarbixamide: 3-(acetylmethylimino)dibenzofuran;
N,N-dimethyl-p-amino-benzalacetamide, N,N-dimethyl-N1. Nl-(p/-dimethylamino)cinnamylideneacetamide: N,N-dimethyl-N',N'-(2-dimethylamino)vinylamide, N'-(2-methylamino)-vinylamide; urea, N,N '-Dimethylurea, N, N, N', N'-
Tetramethylurea; methyl carbamate, NIN-ethyl diethyl carbamate: ε-caprolactam, lq-
Methyl-epsilon-caprolactam, N-amote-epsilon-caglolactam, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, 2-piperidone, N-methyl-2-piperidone, 2-quinolone, m -Me + Ru 2-quinolone, 2-indolinone, N-methyl-
2-indolinone; isocyanuric acid, N, N', N"-
Examples include trimethylisocyanuric acid α and their corresponding sulfur-containing compounds. Particularly preferred compounds are those in which an alkyl group is bonded to nitrogen.

The polymers into which these compounds are introduced by reacting these compounds with alkali gold and/or alkaline earth total addition unsaturated rubbery polymers can be prepared by, for example,
It is manufactured by the method described in No. 49101.

That is, a method in which a diene polymer is polymerized using an alkali metal-based catalyst and/or an alkaline earth metal-based catalyst, and the compound is added to a living diene polymer bath liquid after the polymerization reaction has been completed; Examples include a method in which an alkali metal and/or alkaline earth metal is added to an unsaturated rubber-like polymer such as a rubber-based polymer in a solution dissolved in an appropriate solvent, and then the compound is added and reacted. can.

Alkali metal-based catalysts used in polymerization reactions and addition reactions include metals themselves such as lithium, rubidium, and cesium, or complexes of these metals with hydrocarbon compounds or polar compounds (e.g., rubidium, 2-naphthyllithium, potassium, etc.). -tetrahydrofuran complex, potassium-shedkin ethane complex, etc.) and alkaline earth metal-based catalysts are disclosed in JP-A-51-115590 and JP-A-5
Examples include catalyst systems containing compounds such as barium, strontium, and calcium as main components described in Japanese Patent Application Laid-open No. 2-9090 and JP-A-57-10014+5. It may be used as a catalyst and is not particularly limited.

In order to achieve the purpose of the present invention, the amount of the compound having a -C-N bond (in the formula, M represents an O atom or an S atom) in the molecule should be 0.05 per mole of the catalyst used when polymerizing
~10 mol, preferably 0.2-2 mol.

In order to produce the unsaturated rubber-like polymer to which the metal is added by the post-reaction used in the present invention, the amount of the catalyst used is 0.1 to 9 grams per gram of M-mer. The amount of the compound used is 20 mmol, and the amount of the compound used per mole of the catalyst is the same as above.

After completion of the reaction, the unsaturated rubbery polymer into which the compound has been introduced is recovered from the reaction solution using conventional methods such as addition of a coagulant such as methanol, stripping with water vapor, and the like.

The obtained unsaturated rubbery polymer has the compound introduced at the end of the molecular chain or into the molecular chain as an atomic group of the polymer molecular chain □C□ - O-N, 0-(or SH).

In addition, in the present invention, after the reaction is completed, an unsaturated rubber-like material is introduced into which a salt of the above-mentioned atomic group or a charged octagonal complex is introduced which has significantly improved rebound properties even when reacted with an acid and/or a halogen compound. A polymer is obtained.

The site into which the compound is introduced may be at the end of the molecular chain or any other site, but preferably at the end of the molecular chain. By using a polymer obtained by reacting with a polymer, the improvement in anti-friction elasticity is even greater.

The compound f, an unsaturated rubbery polymer introduced into the polymer chain, is present in a small amount in the rubber component of the rubber composition (10 times the weight, preferably 20 times or more, more preferably 60 times the weight). If it is less than 10 f)S, no improvement in anti-bacterial elasticity can be expected.

When using this rubber in combination with other rubbers, the other rubbers include emulsion polymerized styrene-butadiene copolymer rubber, emulsion polymerized polybutadiene rubber, bath liquid polymerization (anionic polymerization catalyst, Ziegler type catalyst, etc.) Polybutadiene rubber, styrene-phtadiene copolymer rubber, polyisoprene rubber, pumediene-isoglene copolymer rubber, polyalkenamer, etc. and natural rubber are included.Depending on the purpose,
One or more of these rubbers may be selected and used.

The Mooney viscosity (ML 1+4.10°C) of the unsaturated rubbery polymer into which the compound is introduced is usually in the range of 10 to 200, preferably in the range of 20 to 150.

If it is less than 10, the mechanical properties such as tensile strength will be poor, and if it is more than 200, the resulting rubber composition will have poor miscibility when used in combination with other rubbers, making processing operability difficult. This is not preferred because the mechanical properties of the vulcanizate deteriorate.

All or part of the rubber components used in the present invention can be used as oil-extended rubber.

The rubber composition of the present invention is produced by mixing a rubber component and various compounding agents using a mixer such as a roll or Banbury mixer.

The various compounding agents to be used can be selected from those commonly used in rubber compositions, and those suitable for the intended use of the rubber composition.
There are no particular restrictions.

Usually, vulcanization systems include sulfur, stearin Uχ, zinc violet,
Vulcanization accelerators (thiazole type, thiuram type, sulfenamide type, etc.), organic peroxides, etc. are used as reinforcing agents, and various grades of carbon black such as HA F, SA F, etc. Calcium carbonate, Merck, etc. are used as fillers, and process oils, processing aids, vulcanization retarders, anti-aging agents, etc. are used as other compounding agents. The types and parts of these compounding agents are selected depending on the intended use of the rubber composition.6. D. There is no particular limitation in the present invention.

Since the rubber composition of the present invention can adjust anti-peel elasticity and wet skid resistance at a high water content, it is particularly suitable as a rubber material for automobile tire treads, but also for automobile tires and shoe soles. It can also be used for applications such as flooring, anti-vibration rubber, etc.

When the rubber composition of the present invention is used for tire treads, a preferred embodiment is as follows: ◇tl+polybutadiene into which the chemical compound has been introduced, 2-bond units 10 to 90%)/styrene-butadiene copolymer rubber (Bound styrene amount 5-5
0% by weight, 10 to 8 1,2-linked units of butadiene units
0) and/or polyisoprene rubber/high cis 1.4-
Polybutadiene (10-80/20-9010-30 by weight) or (2) Styrene-butadiene copolymer rubber into which the compound is introduced (
Bonded styrene piece 5-50 weight ffi%, 1.2-bond unit of butadiene unit 10-80%)/Styrene-butadiene copolymer rubber (bonded styrene amount 5-50 weight piece, 1.2-butadiene unit) bonding units 10-80%) and/or polyisoprene rubber/high cis 1,4-polybutadiene (10-10010-9010-50fi amount) or less,
The present invention will be specifically explained with reference to Examples.

Production Example 1 A production example of polybutadiene rubber in which a compound having an 10-N bond is introduced into the molecule is described below.

Contents Ht 2-13 stainless steel polymerization reactor 1,
3-butadiene 150y', benzene 820y-, diethylene glycol dimethyl ether (diglyme 90y-
．． 5 mmol and 1.0 mmol of looptillithium (rL-hexane solution) were added, and polymerization was carried out at 40"O for 1 hour while stirring. After the polymerization was completed, the compounds shown in Table 1 were added, and under stirring. The reaction was allowed to proceed for 5 minutes.

The contents of the polymerization reactor were poured into methanol containing 1.5% by weight of EHT to coagulate the resulting polymer.

Mooney viscosity after drying under reduced pressure at 60°C for 24 hours: 1.
2-The amount of bonding units (by infrared spectroscopy) was measured.

The results are also listed in Table 1.

Example 1 Using the rubbers listed in Table 1, each of the mild compounding agents in the formulations listed in Table 2 was cross-mixed in a Gravender type mixer with a capacity of 250 d to obtain each rubber compound composition. Test pieces were prepared by press vulcanization at 160°C for 15 to 25 minutes.

The strength properties were measured according to J.S.K.K-6301, the anti-slip elasticity was measured at 53℃ using a Dunlop trypsometer, and the sweat skid resistance was measured at 23℃ using a Portaple skid tester (Stanley Co., Ltd., UK).
Measured on a road surface of 303-74. The results are shown in Table 3.

Production Example 2 An example of production of styrene-butadiene copolymer rubber incorporating the compound will be shown.

In the same manner as in Production Example 1, 1,6-ptadiene 112.5
1, styrene 37.5y-, tetrahydro 7rano,
751, 0.75 mmol of rubutyllithium was placed in a polymerization vessel, and polymerization was carried out at 45°C for 2 hours. After completion of the M reaction, 2.0 μIJ moles of the compounds listed in Table 4 were subsequently added and reacted. Table 4 shows the properties of the obtained polymer.

Table 4 Example 2 Rubbers listed in Table 4 and high cis 1,4-polybutadiene (
Nippon Zeon Co., Ltd. product N1pol BR1220) was used, and the formulation shown in Table 2 (however, sulfur was 1.8 M parts, and the vulcanization accelerator was N-7 chlorohexyl-2-benzothiazylsulfenamide'ft: 1. A rubber compound composition was prepared according to the method (using 0 weight parts) and press vulcanized to prepare test pieces. The same test scissors as in Example 1 were performed. 5th result
Shown in the table.

Example 3 After the polymerization reaction was completed in Production Example 2, 1,3-butadiene 22 was added to further escape the polymerization to produce a polymer in which the molecule end borrowed butadienyl, and after completion of the polymerization, N-methyl- 2.0 mmol of ε-caglolactam was added and reacted.

The obtained rubber (rubber N0119) was coupled with tin tetrachloride according to a conventional method to produce a styrene-pucdiene copolymer rubber (rubber i (0,20, bound styrene poor 25
The vulcanizate was obtained by mixing at the ratio shown in Table 6 and using the same formulation as in Example 2. Ta.

The test results for these vulcanizates are shown in Table 6.

No. 6 Wheat Production Example 3 An example of production is shown in which a rubber to which alkali has been added in a post-reaction is reacted with the compound.

In a stainless steel B polymerization reactor with an internal volume of 2 stones, 655+- polybutadiene (rubber j1α21, Mooney viscosity 40.1, 2-bond unit 6.8%) and 650 dehydrated leuheptane were charged and stirred to dissolve kg of polybutadiene.

2.3 mmol of helibutyl lithium and 2.3 mmol of tetramethylethyl nondiamine were added to this bath solution, and
After reacting at 0° C. for 1 hour, 2.0 mmol of N,N-dimethylnicotinamide was added and reacted. i′J
All of the produced polymer was recovered in the same manner as in Example A (rubber tray).
'@22).

The above reaction was carried out using styrene-butadiene copolymer rubber (rubber tJQ, 26, Mooney viscosity 60, bonded styrene, Zk 25 two bags, 37 bags of 1,2-bond units of pukudiene units) instead of polybutadiene. (Rubber! 1f
O124).

Example 4 Using the rubber of Production Example 3, using the compounding recipe of Example 1 for polybutadiene and the compounding procedure of Example 2 for styrene-butadiene copolymer rubber, all test specimens were prepared. The same test trip as in the example was conducted. The results are shown in Table 7.

Patent Applicant Nippon Zeon Co., Ltd. Procedural Amendment Written April 8, 1959 1, Indication of the Case 1963 Patent Application No./D, 3rd Disgrace No. 3 Person making the amendment Relationship to the case Patent Applicant Residence Place: 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Procedural amendment (Jisen 1, Case indication: 1989 Patent Application No. 11θ + Oda No. 2, Title of the invention: ゛A Zhu 1be Sairiki 3, Amendment Relationship with the case of a person who does , the division of the patent claim is corrected as follows.

``A rubber composition sliding door consisting of a rubber component and a binder is obtained by reacting with a metal compound having an alkali metal and/or alkaline earth goldstone (in the formula, M represents 0 atom or S Jlx atom). A rubber y characterized in that the rubber component contains at least 10 rubber-like polymers.
+[1 product. 2.Details of the invention i; Dark blue, light blue, 2τ7dan and page 8, all appendix pages 257 and 8 are replaced, one surprise below], styrene-imprene copolymer rubber (normally bonded The amount of styrene is 50 times or less), butadiene-isoprene copolymer rubber, acrylonitrile-butadiene copolymer rubber, polypentadiene rubber, butadiene-piperylene copolymer rubber, butadiene-propylene copolymer rubber, polybentenamer, polyoctenamer, cyclopentene-
Examples include dicyclopentadiene ring-opening copolymer rubber, but are not particularly limited thereto. Furthermore, there are no particular restrictions on the microstructure of the diene units in the polymer.

Claims (1)

[Claims] Reacting an alkali metal and/or alkaline earth metal addition unsaturated rubbery polymer with a compound having a ▲numerical formula, chemical formula, table, etc.▼bond (in the formula, M represents an O or S atom) in the molecule. A rubber composition characterized in that the rubber component contains at least 10% by weight of a rubbery polymer obtained by