JP2013091768A - Polybutadiene rubber, method for manufacturing the same, and rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polybutadiene rubber that is improved in the balance among processability, abrasion resistance, and low-loss property each useful for rubber materials and that is enhanced in their respective performance; a method for manufacturing it; and a rubber composition including the polybutadiene rubber.SOLUTION: This polybutadiene rubber has a Mooney viscosity (ML, 100°C) of 30-120, a ratio of 5% toluene solution viscosity (Tcp) to Mooney viscosity of 1.8-6.0, and a ratio of (z+1)-average molecular weight in terms of polystyrene by GPC to number-average molecular weight of 8 or more, and is a product polymerized with a polymerization catalyst comprising a cobalt compound, a halogen-containing aluminum compound expressed by formula RAlX(in the formula, Ris a (1-10)C hydrocarbyl group; X is a halogen; and n is a number of 1-2), and water.

Description

  The present invention relates to a polybutadiene rubber having improved balance of processability, wear resistance and low loss property useful for rubber materials, and a method for producing the same, and a rubber composition containing the polybutadiene rubber.

Due to the recent increase in energy saving needs, rubber materials are also required to have a characteristic (low loss) that can reduce energy loss. Among the rubber materials, polybutadiene rubber is excellent in properties that reduce energy loss, and as a molecular structure, the cis 1,4 bond content is large, the molecular weight is high, the molecular weight distribution is narrow, the degree of molecular chain branching is small, Realization of a molecular design that satisfies these requirements has been energetically studied through the development of polymerization catalysts.

For example, Patent Document 1 discloses a method for producing high cis-1,4-polybutadiene in which 1,3-butadiene is polymerized using a catalyst comprising a cobalt compound, an acidic metal halide, an alkylaluminum compound, and water. .

Patent Document 2 discloses a method in which 1,3-butadiene is polymerized in a solvent composed of linear or branched aliphatic hydrocarbons using a catalyst composed of diethylaluminum chloride, water, and cobalt octate. Is disclosed.

  However, polybutadiene rubber with a high molecular weight, a narrow molecular weight distribution, and a small degree of molecular chain branching tends to deteriorate the processability when producing a compound obtained by blending carbon black or the like with the rubber. Wearability also tends to deteriorate, and there has been a demand for a method that balances workability and wear resistance while maintaining excellent low-loss properties.

  As a method for improving the processability of polybutadiene, Patent Document 3 discloses a method of treating a polybutadiene polymerization solution with an organoaluminum compound and an alkyl halide compound. Patent Document 4 introduces a method of modifying a rubber by dissolving a rubber having an unsaturated bond in a solvent and reacting with an organic acid halide in the presence of a Lewis acid.

Patent Document 5 discloses a method for improving cold flow properties by polymerizing polybutadiene rubber with a cobalt compound and further reacting with an acid halide, a halogen-containing sulfur compound, a mercapto group-containing alkoxysilane compound, etc., if necessary. Although described, there is no mention of improving the balance between workability, low loss, and wear resistance.

Thereafter, for the purpose of improving the balance between workability, low loss, and wear resistance, a method is disclosed in which polybutadiene rubber is polymerized with a cobalt compound and then modified with a predetermined amount of an organic halogen compound (Patent Documents 6 and 6). 7).
However, from the viewpoint of recent environmental and energy savings, there is a demand for further improving the overall performance while maintaining a balance between workability, low loss, and wear resistance.

Japanese Patent Publication No.38-1243 Japanese Patent Publication No. 61-54808 Japanese Patent Laid-Open No. 51-63891 JP-A-61-225202 Japanese Patent Laid-Open No. 2001-114817 Japanese Patent No. 4123019 JP 2011-79954 A

  The present invention provides a polybutadiene rubber having an improved balance of processability, wear resistance and low loss and improved performance, a method for producing the same, and a rubber composition containing the polybutadiene rubber.

The present invention has a Mooney viscosity (ML _{1 + 4} , 100 ° C.) of 30 to 120, a ratio of 5% toluene solution viscosity (Tcp) to Mooney viscosity of 1.8 to 6.0, z + 1 average molecular weight and number in terms of polystyrene by GPC. The ratio of the average molecular weight is 8 or more, and the polymerization catalyst is a cobalt compound and R ² _3-n AlX _n (wherein R ² is a hydrocarbon group having 1 to 10 carbon atoms, X is halogen, and n is It is related with the polybutadiene rubber polymerized by the catalyst which consists of the halogen-containing aluminum compound and water which are represented by 1-2.

The present invention also relates to the above-mentioned method for producing polybutadiene rubber, wherein the polybutadiene rubber is obtained by modification with an organic halogen compound.

The present invention also relates to a rubber composition comprising the polybutadiene rubber described above.

While the polybutadiene rubber has a molecular structure with a small degree of branching, it has an ultrahigh molecular weight component defined by the value of the number average molecular weight, the ratio of z + 1 average molecular weight and number average molecular weight, and thus wear resistance and workability. Finding that low loss can be improved in a well-balanced manner, and finding that the molecular structure can be effectively obtained by modifying a polymerization catalyst system using a cobalt catalyst with an organic halogen compound to complete the present invention. It came.
As a result, it is possible to provide a polybutadiene rubber having an improved balance of processability, wear resistance and low loss, a method for producing the same, and a rubber composition containing the polybutadiene rubber.

(Regarding polybutadiene rubber)

(Mooney viscosity)
The Mooney viscosity of the polybutadiene rubber of the present invention is 30 to 120, preferably 35 to 110, and more preferably 40 to 105.
When the Mooney viscosity is larger than the above range, the workability is remarkably deteriorated. When the Mooney viscosity is smaller than the above range, the wear resistance and the low loss property are deteriorated.

(Tcp / ML)
The ratio (abbreviated as Tcp / ML) of 5% toluene solution (Tcp) to Mooney viscosity (ML _{1 + 4} , 100 ° C.) is 1.8 to 6.0, preferably 2.0 to 5.0. If the Tcp / ML ratio is smaller than the above range, the degree of branching of the molecular chain is increased, the wear resistance and the low loss property are lowered, and if it is larger than the above range, the workability is deteriorated.

(Mz + 1 / Mn)
The ratio of z + 1 average molecular weight and number average molecular weight in terms of polystyrene by gel permeation chromatography (GPC) (abbreviated as Mz + 1 / Mn) is a value affected by high molecular weight components, and is preferably 8 or more, 9 or more Is particularly preferred.
If the value of Mz + 1 / Mn is smaller than 8, it is not preferable because there is little improvement in low loss.

Number average molecular weight, mass average molecular weight, z average molecular weight, z + 1 average molecular weight are

それぞれ式１〜４で表される。MnよりMw、MwよりMzさらにMz+1のほうが高分子量側を表しており、Mz+1/Mnによって高分子量側への分子の広がりを表す。
すなわち、Mz+1/Mnの値が大きくなるほど、高分子量領域での分子量分布の広がりを示す。
本願発明で得られるポリブタジエンは、この高分子量領域での分子量分布の広がりを示す特徴を有している。

Each is represented by Formulas 1-4. Mw is higher than Mn, Mz is higher than Mw, and Mz + 1 is higher in molecular weight, and Mz + 1 / Mn indicates the spread of molecules toward the higher molecular weight.
That is, the larger the value of Mz + 1 / Mn, the wider the molecular weight distribution in the high molecular weight region.
The polybutadiene obtained in the present invention has a feature that indicates the broadening of the molecular weight distribution in the high molecular weight region.

(Polybutadiene)
The polybutadiene used as a raw material preferably has a T-cp / ML of 2.0 to 4.0, particularly 2.4 to 3.2. If it is larger than this value, the workability will be poor, and if it is low, the expected physical properties cannot be obtained. Further, Mw / Mn is preferably 1.8 to 3.4, particularly preferably 2.0 to 3.0. If it is larger than this range, desired physical properties cannot be obtained, and if it is smaller than this range, workability becomes a problem.

(Polybutadiene rubber polymerization catalyst)
As the polymerization catalyst for the raw polybutadiene rubber, a cobalt catalyst is preferably used.

  As the cobalt compound of the cobalt-based catalyst, a cobalt salt or complex is preferably used. Particularly preferred are cobalt salts such as cobalt chloride, cobalt bromide, cobalt nitrate, cobalt octylate, cobalt naphthenate, cobalt acetate, cobalt malonate, cobalt bisacetylacetonate and trisacetylacetonate. , Ethyl acetoacetate cobalt, cobalt halide triarylphosphine complex, trialkylphosphine complex, organic base complexes such as pyridine complex and picoline complex, or ethyl alcohol complex.

The halogen-containing aluminum compound in the cobalt-based catalyst composition includes R ² _3-n AlX _n (wherein R ² is a hydrocarbon group having 1 to 10 carbon atoms, X is a halogen, and n is a number of 1 to 2). Is preferred). Examples thereof include dialkylaluminum halides such as dialkylaluminum chloride and dialkylaluminum bromide, alkylaluminum sesquichlorides such as alkylaluminum sesquichloride and alkylaluminum sesquibromide, and alkylaluminum dihalides such as alkylaluminum dichloride and alkylaluminum dibromide. Specific examples of the compound include diethyl aluminum monochloride, diethyl aluminum monobromide, dibutyl aluminum monochloride, ethyl aluminum sesquichloride, ethyl aluminum dichloride, dicyclohexyl aluminum monochloride, diphenyl aluminum monochloride, and the like.

The organoaluminum compound in the cobalt-based catalyst composition is preferably one represented by R ³ ₃ Al (wherein R ³ represents a hydrocarbon group having 1 to 10 carbon atoms). For example, trialkylaluminum compounds such as triethylaluminum, trimethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum and the like can be mentioned.

  Aluminoxane may also be used. The aluminoxane is obtained by bringing an organoaluminum compound and a condensing agent into contact with each other, and includes a chain aluminoxane represented by the general formula (-Al (R ') O-) n or a cyclic aluminoxane. (R ′ is a hydrocarbon group having 1 to 10 carbon atoms, including those partially substituted with a halogen atom and / or an alkoxy group. N is the degree of polymerization and is 5 or more, preferably 10 or more) . Examples of R ′ include methyl, ethyl, propyl, and isobutyl groups, with methyl and ethyl groups being preferred. Examples of the organoaluminum compound used as an aluminoxane raw material include trialkylaluminums such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, and mixtures thereof.

  Among these, a catalyst system composed of a cobalt compound, a halogen-containing aluminum compound and water, or a catalyst system composed of a cobalt compound, a halogen-containing aluminum compound, water and an organoaluminum compound is preferable.

When a cobalt-based catalyst composition comprising a cobalt compound, a halogen-containing organoaluminum compound, water, and an organoaluminum compound is used, 1 × 10 ⁻⁷ to 1 × 10 ⁻⁷ to 1 mol of 1,3-butadiene. A range of 1 × 10 ⁻³ mol is preferred. The halogen-containing organoaluminum compound is preferably in the range of 1 × 10 ⁻⁵ to 1 × 10 ⁻¹ mol. Moreover, about water, it is preferable to exist in the range of 1 * 10 < ^-5 > ^-1 * 10 <^-1> mol. The organoaluminum compound is preferably in the range of 1 × 10 ⁻⁵ to 1 × 10 ⁻¹ mol.

As a point of the invention, the polymerization conditions of the polybutadiene before the modification with the organic halogen compound are important for creating effects such as low fuel consumption of the finally produced polybutadiene.
In particular, the “ratio of aluminum compound to water” and “ratio of halogen-containing organoaluminum compound to organoaluminum compound” used in the polymerization step described below are major factors.
In order to create the excellent physical properties of polybutadiene, it is essential to satisfy these two factors at the same time in the polymerization stage. If only one of these conditions is met, the effect of reducing the fuel consumption of the final polybutadiene will be created. It is difficult to do.

(Ratio of aluminum compound to water)
The addition amount of the halogen-containing organoaluminum compound and the organoaluminum compound used in the cobalt-based catalyst composition is 0.95 to 1.30 times, especially 0.98 to 1.25 times the amount of water to be added, In particular, it is preferably 1.0 to 1.15 times. If it is larger than this range, desired physical properties cannot be obtained, and if it is smaller than this range, workability is deteriorated.
The addition amount of the halogen-containing organoaluminum compound and the organoaluminum compound and the ratio of water to be added are particularly important in defining the linearity of polybutadiene.

(Ratio of halogen-containing organoaluminum compound to organoaluminum compound)
The halogen-containing organoaluminum compound used in the cobalt-based catalyst composition is preferably 1 to 6 times, particularly preferably 2 to 4 times that of the organic aluminum. When it is larger than this range, the gel becomes a problem, and when it is smaller, the polymerization activity decreases.

  As the order of addition of the catalyst components, it is preferable to add water in an inert solvent and mix uniformly, add a halogen-containing organoaluminum compound, add a cobalt compound, and start polymerization. It is preferable to add a cobalt compound after aging for a predetermined time after adding the halogen-containing organoaluminum compound. The aging time is preferably from 0.1 to 24 hours. The aging temperature is preferably 0 to 80 ° C.

(Polymerization solvent)
As a polymerization solvent, aromatic hydrocarbons such as toluene, benzene and xylene, aliphatic hydrocarbons such as n-hexane, butane, heptane and pentane, alicyclic hydrocarbons such as cyclopentane and cyclohexane, 1-butene, Olefinic hydrocarbons such as C4 fraction such as cis-2-butene and trans-2-butene, hydrocarbon solvents such as mineral spirit, solvent naphtha, kerosene, halogenated hydrocarbon solvents such as methylene chloride, etc. Can be mentioned. Further, 1,3-butadiene itself may be used as a polymerization solvent.

  Among these, benzene, cyclohexane, or a mixture of cis-2-butene and trans-2-butene is preferably used.

(Molecular weight regulator)
As the molecular weight modifier, for example, non-conjugated dienes such as cyclooctadiene and allene, or α-olefins such as ethylene, propylene, and butene-1 known at the time of polymerization can be used.
Particularly preferred is cyclooctadiene, preferably 3 to 30 mmol, more preferably 5 to 18 mmol, per mole of 1,3-butadiene. Use of an amount outside this range is not preferable because it causes a problem of deviation in ML viscosity.

  The polymerization temperature is preferably in the range of -30 to 100 ° C, particularly preferably in the range of 30 to 80 ° C. The polymerization time is preferably in the range of 10 minutes to 12 hours, particularly preferably 30 minutes to 6 hours. The polymerization pressure is carried out under normal pressure or up to about 10 atm (gauge pressure).

(Organic halogen compounds)
In order to impart desired viscoelastic properties to the polybutadiene rubber produced by the above cobalt-based catalyst, it is preferable to modify with an organic halogen compound. The unmodified product which is not modified with an organic halogen compound satisfies the desired properties in Mooney viscosity and Tcp / ML ratio, but cannot satisfy the desired properties in Mz + 1 / Mn.

As the organic halogen compound, an organic halogen compound represented by the general formula R ¹ R ² R ³ CX can be used. In the formula, R ¹ is hydrogen, an alkyl group, an aryl group, a chloro-substituted alkyl group, an alkoxy group, R ² is hydrogen, an alkyl group, an aryl group, chloro, bromo, etc., and R ² + R ³ is oxygen. R ³ is an alkyl group, an aryl group, a vinyl group, chloro, bromo and the like, and X is a halogen such as chloro and bromo. When R ¹ and R ² are hydrogen, R ³ is preferably an aryl group. The above alkyl group may be saturated or unsaturated, and may be linear, branched or cyclic. An aliphatic hydrocarbon group etc. are mentioned.

Specific examples of the compound include chlorinated or brominated compounds such as methyl, ethyl, iso-propyl, iso-butyl, t-butyl, phenyl, benzyl, benzoyl and benzylidene. Further, methyl chloroformate, bromoformate, chlorodiphenylmethane, chlorotriphenylmethane, and the like can be given. Of these, t-butyl chloride is preferred.

A cobalt compound, a halogen-containing aluminum compound, and a cobalt compound and a halogen-containing aluminum compound may be added together with the organic halogen compound. As the cobalt compound and the halogen-containing aluminum compound, the cobalt compounds and halogen-containing aluminum compounds exemplified as the catalyst component can be used.

The addition amount of the organic halogen compound is desirably 0.05 to 0.4 times the total addition amount of the halogen-containing organoaluminum compound and the organoaluminum compound, and 1 × 10 ⁻⁶ to 1 per mole of butadiene. × 10 ⁻³ mol, particularly 1 × 10 ⁻⁵ to 1 × 10 ⁻⁴ mol is preferable. If the amount is more than the above range, gelation of the resulting polybutadiene tends to occur.

About reaction temperature of an organic halogen compound, it is 20-100 degreeC, Preferably it is 30-80 degreeC.

The reaction time of the organic halogen compound is agitated and mixed for 10 minutes to 150 minutes.

The modification reaction between the organic halogen compound and polybutadiene may be carried out after the polymerization reaction, after the polymerization reaction is stopped after the polymerization, or after the polymerization reaction is stopped after the polymerization, in the reaction product. Alternatively, the solvent or unreacted monomer remaining in the substrate may be dissolved again in cyclohexane or the like after the dried product obtained by removing the solvent or unreacted monomer by a steam stripping method or a vacuum drying method. After the denaturation reaction, the inside of the reaction vessel is released as necessary, and post-treatment such as washing and drying steps is performed.

(Rubber composition)
The polybutadiene rubber obtained by the present invention is blended alone or blended with other synthetic rubber or natural rubber, and if necessary, is oil-extended with process oil, and then a filler such as carbon black or silica, or a vulcanizing agent. Vulcanization accelerators and other normal compounding agents are added to vulcanize the tires, anti-vibration rubber, belts, hoses, seismic isolation rubber and other industrial items, and men's shoes, women's shoes, sports shoes and other footwear. Used for rubber applications. In that case, the rubber component is preferably blended so as to contain at least 10% by weight of the polybutadiene of the present invention.

(Other synthetic rubber)
As the other synthetic rubber contained in the rubber composition, a vulcanizable rubber is preferable. Specifically, ethylene propylene diene rubber (EPDM), nitrile rubber (NBR), butyl rubber (IIR), chloroprene rubber (CR), Examples thereof include polyisoprene, high cis polybutadiene rubber, low cis polybutadiene rubber (BR), styrene-butadiene rubber (SBR), butyl rubber, chlorinated butyl rubber, brominated butyl rubber, and acrylonitrile-butadiene rubber. Among these, SBR is preferable.
Further, among SBR, solution-polymerized styrene butadiene copolymer rubber (S-SBR) is particularly preferable. These rubbers may be used alone or in combination of two or more.

As the microstructure of the solution-polymerized styrene butadiene copolymer rubber (S-SBR) used in the present invention, the styrene content is 15 to 35% by weight, preferably 17 to 30% by weight, and the vinyl bond content of the butadiene portion is 30 to 30%. By using 75%, preferably 32 to 72% of S-SBR, 100 parts by weight of the rubber component, 30 parts by weight or more and less than 90 parts by weight, preferably 50 to 80 parts by weight, the above effect is exhibited. If the blending amount of S-SBR is small, the wet performance decreases, which is not preferable. Conversely, if it is large, the wear resistance and low loss property deteriorate, which is not preferable.
Such S-SBR is known, and for example, commercially available products such as Nippon Zeon Nipol NS110R and Asahi Kasei Asaprene 1204 can be used.

(Silane coupling agent)
As another additive component, the silane coupling agent is an organosilicon compound represented by the general formula R ⁷ nSiX 4 -n, where R ⁷ is a vinyl group, acyl group, allyl group, allyloxy group, amino group, epoxy group. , A mercapto group, a chloro group, an alkyl group, a phenyl group, hydrogen, a styryl group, a methacryl group, an acrylic group, a ureido group and the like, an organic group having 1 to 20 carbon atoms, and X is a chloro group , An alkoxy group, an acetoxy group, an isopropenoxy group, an amino group, and the like, and n represents an integer of 1 to 3.

Among the R ⁷ components of the silane coupling agent, those containing a vinyl group and / or a chloro group are preferable.

Specific examples of silane coupling agents that can be used commercially include, but are not limited to, the following. Bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, bis (2-triethoxysilylpropyl) tetrasulfide, bis (3 -Trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylpropyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethoxysilane 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxy Rylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazole tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl Methacrylate monosulfide, vinyltrichlorosilane, methylvinyldichlorosilane, divinyldichlorosilane, dimethylvinylchlorosilane, chloromethyldimethylvinylsilane, methoxydimethylvinylsilane, trimethoxyvinylsilane, dimethyldivinylsilane, ethoxydimethylvinylsilane, diacetoxymethyldinylsilane, allyl Oxydimethylvinylsilane, diethoxymethylvinylsilane, bis (di Tilamino) methylvinylsilane, phenylvinyldichlorosilane, triacetoxyvinylsilane, 3-chloropropylmethyldivinylsilane, diethoxydivinylsilane, dimethylethylmethylketoxyvinylsilane, dimethylisobutoxyvinylsilane, triethoxyvinylsilane, methylphenylvinylchlorosilane, methylphenyl Vinylsilane, dimethylisopentyloxyvinylsilane, 4-bromophenyldimethylvinylsilane, 3-aminophenoxydimethylvinylsilane, 4-aminophenoxydimethylvinylsilane, dimethylpiperidinomethylvinylsilane, dimethyl-2-[(2-ethoxyethoxy) ethoxy] vinylsilane , Divinylmethylphenoxysilane, dimethyl-P-anisylvinylsilane, tris (1 Methylvinyloxy) vinylsilane, triisopropoxyvinylsilane, diethoxy-2-piperidinoethoxyvinylsilane, diphenylvinylchlorosilane, 3-dimethylvinylphenyl N, N-diethylcarbomate, triphenoxyvinylsilane, 1,3-divinyl-1, 1,3,3-tetramethyldisiloxane, 1,3-divinyl-1,1,3,3-tetramethyldisilazane, 1- (4-methylpiperidinomethyl) -1,1,3,3- Tetramethyl-3-vinyldisiloxane, 1,4-bis (dimethylvinylsilyl) benzene, 1,4-bis (dimethylvinylsiloxy) benzene, 1,3-bis (dimethylvinylsiloxy) benzene, 1,1,3 , 3-tetraphenyl-, 3-divinyldisiloxane, 1,3,5-trimethyl-1, , 5-trivinylcyclotrisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, tetrakis (dimethylvinylsiloxymethyl) methane, 3-chloropropyltrimethoxysilane ,and so on.

The addition amount of the additive silane coupling agent is preferably 0.2% to 20%, particularly preferably 5% to 15% with respect to the filler amount.
If it is less than the above range, it is not preferable because it causes scorch. Moreover, since it will become the cause of a deterioration of a tensile characteristic and elongation when it exceeds more than said range, it is unpreferable.

It is also possible to produce a rubber-modified impact-resistant polystyrene resin composition that is used as a modifier for plastics, for example, impact-resistant polystyrene.

  As a method for producing the rubber-modified impact-resistant polystyrene resin composition, a method of polymerizing a styrene monomer in the presence of a rubbery polymer is adopted, and a bulk polymerization method or a bulk suspension polymerization method is economical. This is an advantageous method. Examples of styrene monomers include those conventionally used for producing rubber-modified impact-resistant polystyrene resin compositions such as styrene, α-methylstyrene, alkyl-substituted styrene such as p-methylstyrene, and halogen-substituted styrene such as chlorostyrene. One kind or a mixture of two or more kinds of styrenic monomers are used. Of these, styrene is preferred.

  In addition to the rubber-like polymer, a styrene-butadiene copolymer, ethylene-propylene, ethylene-vinyl acetate, acrylic rubber, etc. may be used in combination within 50% by weight with respect to the rubber-like polymer as necessary during production. it can. Moreover, you may blend the resin manufactured by these methods. Furthermore, you may manufacture by mixing the polystyrene-type resin which does not contain the rubber-modified polystyrene-type resin composition manufactured by these methods. As an example of the bulk polymerization method described above, a rubbery polymer (1 to 25% by weight) is dissolved in a styrene monomer (99 to 75% by weight), and in some cases, a solvent, a molecular weight regulator, a polymerization initiator. Etc. are added to convert the rubber-like polymer into particles dispersed to a styrene monomer conversion rate of 10 to 40%. Until the rubber particles are produced, the rubber phase forms a continuous phase. Furthermore, the polymerization is continued until the conversion to a dispersed phase as a rubber particle (particulation step) (polymerization step) to polymerize to a conversion rate of 50 to 99% to produce a rubber-modified impact-resistant polystyrene resin composition.

The dispersed particles (rubber particles) of a rubbery polymer are particles dispersed in a resin, and are composed of a rubbery polymer and a polystyrene resin. The polystyrene resin can be grafted or not grafted to the rubbery polymer. Occluded. The diameter of the dispersed particles of the rubbery polymer referred to in the present invention can be suitably produced in the range of 0.5 to 7.0 μm, preferably in the range of 1.0 to 3.0 μm.

  A graft ratio in the range of 150 to 350 can be preferably produced. It may be a batch type or a continuous production method and is not particularly limited.

The raw material solution mainly composed of the above-mentioned styrene monomer and rubber polymer is polymerized in a complete mixing reactor, and as a complete mixing reactor, the raw material solution maintains a uniform mixed state in the reactor. As long as it is preferable, a stirring blade of a type such as a helical ribbon, a double helical ribbon, or an anchor is preferable. It is preferable that a draft tube is attached to the helical ribbon type stirring blade to further enhance the vertical circulation in the reactor.

The rubber-modified impact-resistant polystyrene-based resin composition includes a stabilizer such as an antioxidant and an ultraviolet absorber, a release agent, a lubricant, a colorant, various fillers, and various fillers as necessary at the time of production and after production. Known additives such as plasticizers, higher fatty acids, organic polysiloxanes, silicone oils, flame retardants, antistatic agents and foaming agents may be added. The rubber-modified impact-resistant polystyrene resin composition of the present invention can be used in various known molded products, but is used in the fields of electrical and industrial applications because of its excellent flame resistance, impact strength, and tensile strength. Suitable for injection molding. For example, it can be used in a wide range of applications such as color televisions, radio cassettes, word processors, typewriters, facsimiles, VTR cassettes, telephone housings, and other household appliances and industrial applications.

Mooney viscosity (ML _{1 + 4} , 100 ° C.) : In accordance with JIS-K6300, using a Mooney viscometer (SMV-200) manufactured by Shimadzu Corporation, preheat at 100 ° C. for 1 minute, then measure for 4 minutes. Expressed as Mooney viscosity (ML _{1 + 4} , 100 ° C.).

Toluene solution viscosity (Tcp) : After 2.28 g of polymer was dissolved in 50 ml of toluene, viscometer calibration standard solution (JIS Z8809) was used as a standard solution. 400 was used and measured at 25 ° C.

z + 1 average molecular weight, number average molecular weight: Gel permeation (permeation) chromatography (GPC, manufactured by Tosoh Corporation) at a temperature of 40 ° C. using polystyrene as a standard substance and polystyrene as a solvent, and obtained from the obtained molecular weight distribution curve. The z + 1 average molecular weight and the number average molecular weight were calculated using a calibration curve.

Processability: Evaluated in Mooney viscosity of unvulcanized. In accordance with JIS-K6300, using a Mooney viscometer (SMV-200) manufactured by Shimadzu Corporation, preheat at 100 ° C for 1 minute, then measure for 4 minutes to obtain the rubber Mooney viscosity (ML _{1 + 4} , 100 ° C) displayed. The smaller the value, the better the workability.

Rebound resilience of the vulcanizate : According to BS903, the rebound resilience was measured at room temperature using a Dunlop trypometer, and Comparative Example 1 was indicated as 100. The larger the index, the better the low loss property.

The tan δ of the vulcanized product was measured using EPLEXOR 100N manufactured by GABO under the conditions of a temperature of 50 ° C., a frequency of 10 Hz, and a dynamic strain of 0.3%. The smaller the index, the better the low loss (low fuel consumption).

Abrasion resistance of vulcanizate : The Lambourn abrasion index was measured at a slip rate of 60% according to the measurement method defined in JIS K6264, and the index was displayed with Comparative Example 1 as 100. The higher the index, the better.

(Prototype 1)
In a 1.5 liter stainless steel autoclave sufficiently purged with nitrogen, 1 liter of a cyclohexane-C4 fraction mixed solution containing 38.0% by weight of 1,3-butadiene (cyclohexane 25.5% by weight, cis- 2-butene-containing C4 fraction containing 36.5% by weight), and then 2.11 mmol of water, 1.7 mmol of diethylaluminum monochloride and 0.58 mmol of triethylaluminum were added and stirred. And 12.21 mmol of cyclooctadiene was added. After the temperature of the autoclave was raised and the internal temperature reached 49.5 ° C., 0.0031 mmol of cobalt octoate was added, and a polymerization reaction was carried out at 50 ° C. for 30 minutes. 30 minutes after the start of polymerization, 0.40 mmol of t-butyl chloride was added and reacted for 5 minutes.
Antiaging agent was added there and it vacuum-dried at 100 degreeC for 1 hour. Table 1 shows the physical properties of the obtained polybutadiene rubber.

(Prototype 2)
Polybutadiene was produced in the same manner as in prototype 1, except that 14.25 mmol of cyclooctadiene and 0.6 mmol of t-butyl chloride were added as additives to be added during the polymerization.

(Prototype 3)
Polybutadiene was produced in the same manner as in prototype 2, except that 14.25 mmol of cyclooctadiene was added as an additive during the polymerization, and 0.037 mmol of anti-aging agent was added after 30 minutes of polymerization.

(Prototype 4)
Polybutadiene was produced in the same manner as in Prototype 3 except that 9.77 mmol of cyclooctadiene was added as an additive to be added during the polymerization, and 0.074 mmol of an antioxidant was added after 30 minutes of polymerization.

(Prototype 5)
Polybutadiene was produced in the same manner as in prototype 4 except that 0.6 mmol of t-butyl chloride was added and the reaction was performed for 10 minutes.

(Prototype 6)
Polybutadiene was produced in the same manner as in prototype 4 except that 0.6 mmol of t-butyl chloride was added and the reaction was performed for 20 minutes.

(Prototype 7)
In a 1.5 liter stainless steel autoclave sufficiently purged with nitrogen inside, 1 liter of cyclohexane-C4 fraction mixed solution containing 43.0% by weight of 1,3-butadiene (cyclohexane 25.5% by weight, cis- 2-butene-containing C4 fraction containing 36.5% by weight), and then water 2.00 mmol, diethylaluminum monochloride 2.27 mmol, and triethylaluminum 0.76 mmol were added and stirred. And 13.84 mmol of cyclooctadiene was added.
After the temperature of the autoclave was raised and the internal temperature reached 49.5 ° C., 0.0013 mmol of cobalt octoate was added, and a polymerization reaction was carried out at 50 ° C. for 30 minutes. After 30 minutes from the start of polymerization, 0.074 mmol of anti-aging agent was added, 0.6 mmol of t-butyl bromide was added, and the mixture was reacted for 20 minutes. Antiaging agent was added there and it vacuum-dried at 100 degreeC for 1 hour.

(Prototype 8)
In a 1.5 liter stainless steel autoclave sufficiently purged with nitrogen inside, 1 liter of cyclohexane-C4 fraction mixed solution containing 43.0% by weight of 1,3-butadiene (cyclohexane 25.5% by weight, cis- 2-butene-containing C4 fraction containing 36.5% by weight), and then water 2.00 mmol, diethylaluminum monochloride 2.27 mmol, and triethylaluminum 0.76 mmol were added and stirred. And 13.84 mmol of cyclooctadiene was added.
After the temperature of the autoclave was raised and the internal temperature reached 49.5 ° C., 0.0013 mmol of cobalt octoate was added, and a polymerization reaction was carried out at 50 ° C. for 30 minutes. After 30 minutes from the start of polymerization, 0.074 mmol of anti-aging agent was added, 0.6 mmol of t-butyl bromide was added, and the mixture was reacted for 20 minutes.
Antiaging agent was added there and it vacuum-dried at 100 degreeC for 1 hour.

(Prototype 9)
Polybutadiene was produced in the same manner as in Prototype 8, except that 0.4 mmol of t-butyl bromide was added after the addition of the antioxidant.

(Comparative Example 1)
Prototype 7 was used as a butadiene rubber, and a vulcanizing agent was mixed with an open roll after kneading with SBR and silica using a 250 cc lab plast mill according to the formulation shown in Table 2. Subsequently, press vulcanization was performed at a temperature of 160 ° C., and physical properties were evaluated by the obtained vulcanized test pieces.

Example 1
Evaluation was conducted in the same manner as in Comparative Example 1 except that Prototype 1 was used as the butadiene rubber.

(Example 2)
Evaluation was conducted in the same manner as in Comparative Example 1 except that prototype 2 was used as the butadiene rubber.

(Example 3)
Evaluation was conducted in the same manner as in Comparative Example 1 except that prototype 3 was used as the butadiene rubber.

Example 4
Evaluation was conducted in the same manner as in Comparative Example 1 except that prototype 4 was used as the butadiene rubber.

(Example 5)
Evaluation was conducted in the same manner as in Comparative Example 1 except that prototype 5 was used as the butadiene rubber.

(Example 6)
Evaluation was performed in the same manner as in Comparative Example 1 except that prototype 6 was used as the butadiene rubber.

(Example 7)
Evaluation was conducted in the same manner as in Comparative Example 1 except that Prototype 8 was used as the butadiene rubber.

(Example 8)
Evaluation was conducted in the same manner as in Comparative Example 1 except that Prototype 9 was used as the butadiene rubber.

Table 1 shows the physical rubber properties of the obtained prototype.

The evaluation results of the resulting blend are shown in Table 2.

ＳＢＲ ：市販溶液重合ＳＢＲ
シリカ：東ソー・シリカ（株）製、商品名 ニップシールAQ
シランカップリング剤：デグサ・ヒュルヌ製、商品名 Si69
オイル：サンセンオイル４２４０
酸化亜鉛：堺化学工業 Sazex 1号
ステアリン酸：花王ステアリン酸
老化防止剤：住友化学 アンチゲン６Ｃ
硫黄： 細井化学工業（株）製の硫黄
加硫促進剤１： 大内新興化学工業（株）製のノクセラーＣＺ
加硫促進剤２： 大内新興化学工業（株）製のノクセラーＤ

SBR: Commercial solution polymerization SBR
Silica: Tosoh Silica Co., Ltd., trade name: Nip Seal AQ
Silane coupling agent: Product name Si69, manufactured by Degussa Hyrun
Oil: Sansen Oil 4240
Zinc oxide: Sakai Chemical Industry Sazex No. 1 stearic acid: Kao stearate anti-aging agent: Sumitomo Chemical Antigen 6C
Sulfur: Sulfur vulcanization accelerator manufactured by Hosoi Chemical Industry Co., Ltd. 1: Noxeller CZ manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.
Vulcanization accelerator 2: Noxeller D from Ouchi Shinsei Chemical Co., Ltd.

The rubber can also be used for industrial belts, golf balls, anti-vibration rubber, seismic isolation rubber, fenders and the like.
Furthermore, it can also be applied as a material for HISP and ABS.

Claims (3)

Mooney viscosity (ML _{1 + 4} , 100 ° C.) is 30 to 120, ratio of 5% toluene solution viscosity (Tcp) to Mooney viscosity is 1.8 to 6.0, ratio of z + 1 average molecular weight and number average molecular weight in terms of polystyrene by GPC Is 8 or more, and the polymerization catalyst is a cobalt compound and R ² _3-n AlX _n (wherein R ² represents a hydrocarbon group having 1 to 10 carbon atoms, X represents a halogen, and n represents 1 to 2). The polybutadiene rubber is polymerized by a catalyst comprising a halogen-containing aluminum compound represented by formula (II) and water. The method for producing a polybutadiene rubber according to claim 1, wherein the polybutadiene rubber is obtained by modification with an organic halogen compound. A rubber composition comprising the polybutadiene rubber according to claim 1.