KR20190094110A - Crumb of conjugated diene polymer and vale molded article - Google Patents

Abstract

The present invention aims to inhibit crumb detachment of a conjugated diene-based polymer from a veil surface of the conjugated diene-based polymer and swelling of a veil. The present invention relates to: a crumb of a conjugated diene polymer with a specific surface area of 0.7 to 3.2 m^2/g; a method for manufacturing the veil which can obtain the veil by compression molding the crumb; and the veil of the conjugated diene polymer having a specific surface area of 0.005 to 0.05 m^2/g.

Description

CRUMB OF CONJUGATED DIENE POLYMER AND VALE MOLDED ARTICLE}

The present invention relates to crumbs and bales of conjugated diene polymers.

In the polymer manufacturing process of the conjugated diene obtained by solution polymerization, generally the particle | grain (crude) of the solid conjugated diene polymer is obtained by desolventing the mixture of the conjugated diene polymer and solvent obtained after superposition | polymerization, and compressing this particle is a bale It is processed into the molded object of a rectangular parallelepiped called. For example, Patent Literature 1 discloses a method for producing a bale by producing pellets from rubber melt-kneaded and extruded, and compression molding the rubber pellets. Further, for example, Patent Document 2 discloses a molding apparatus for a bale and a method for manufacturing the bale, which can prevent the metal component of the bale from being mixed.

Japanese Patent Laid-Open No. 2012-86424 Japanese Patent Laid-Open No. 2008-93954

In recent years, the demand for abrasion resistance tends to be strong in automobile tires, which are the main uses of conjugated diene polymers, and in order to cope with this, the demand for high molecular weight of conjugated diene polymers is increasing. Thus, the present inventors have studied the problems occurring in the bale with high molecular weight. The crumb of the conjugated diene polymer obtained by polymerizing the conjugated diene polymer after depolymerization tends to peel off and fall off as the molecular weight increases, and the crumb is formed around the molding machine or around the conveyor for conveying the bale after molding for a long time. Since scattering occurs, problems in the working environment may occur. In addition, although the veil tends to expand immediately after molding, the higher the molecular weight of the conjugated diene polymer is, the larger the tendency may be, making it difficult to receive the container. Therefore, in the veil of a high molecular weight conjugated diene polymer, it is desired to suppress peeling of the particle from the surface and the expansion rate.

Therefore, an object of the present invention is to suppress crumb peeling and expansion of the conjugated diene polymer from the bale surface of the conjugated diene polymer.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject of the said prior art, as a result, the specific surface area of the crumb and the veil of a conjugated diene polymer was made into the specific range, and the crumb peeling of the conjugated diene polymer from the surface of a bale and expansion of a veil were carried out. It was found that this was suppressed.

That is, this invention is as follows.

[One]

Crum of conjugated diene polymer having a specific surface area of 0.7 m 2 / g to 3.2 m 2 / g.

[2]

The crumb as described in [1] in which a conjugated diene polymer contains 30-90 mass% of components with a molecular weight of 1 million or more.

[3]

The crumb as described in [1] or [2] containing 1-20 mass parts of process oil with respect to 100 mass parts of conjugated diene polymers.

[4]

A bale of conjugated diene polymer having a specific surface area of from 0.005 m 2 / g to 0.05 m 2 / g.

[5]

A method for producing a bale, in which a crumb of a conjugated diene polymer having a specific surface area of 0.7 m 2 / g to 3.2 m 2 / g is produced, and the bale is obtained by compression molding.

[6]

The manufacturing method of the veil as described in [5] which further has the process of sifting the crumb of the said conjugated diene polymer.

In the veil of this invention, crumb peeling of the conjugated diene polymer from a surface is suppressed and there is little expansion after shaping | molding.

EMBODIMENT OF THE INVENTION Hereinafter, the concrete content (henceforth "this embodiment") for implementing this invention is demonstrated in detail.

In addition, this invention is not limited to the following embodiment, It can variously deform and implement within the range of the summary.

[Conjugated Diene Polymer]

The monomer which becomes a raw material of the conjugated diene polymer used for this embodiment will not be specifically limited if it is a conjugated diene compound which can superpose | polymerize, For example, 1, 3- butadiene, isoprene, 2, 3- dimethyl- 1, 3- butadiene, 1 , 3-pentadiene, 3-methyl-1,3-pentadiene, 1,3-heptadiene, 1,3-hexadiene and the like. Among these, 1,3-butadiene and isoprene are preferable from a viewpoint of industrial availability, and 1,3-butadiene is preferable for the purpose of providing wear resistance, elasticity, and strength to the tread of a tire. These may use not only 1 type but 2 types or more together. When allene, acetylene, etc. are contained as an impurity in a conjugated diene compound, there exists a possibility of inhibiting the modification reaction of a polymer terminal. Therefore, it is preferable that the sum total of content concentration (mass) of these impurities is 200 ppm or less, It is more preferable that it is 100 ppm or less, It is further more preferable that it is 50 ppm or less.

Although it does not specifically limit as allene, For example, propadiene, 1,2-butadiene, etc. are mentioned. Although it does not specifically limit as acetylene, For example, ethyl acetylene, vinyl acetylene, etc. are mentioned.

The conjugated diene polymer used for this embodiment may be a copolymer of the said conjugated diene monomer and an aromatic vinyl compound. The aromatic vinyl compound may be a monomer copolymerizable with the conjugated diene compound, and is not particularly limited. For example, styrene, m or p-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, diphenylethylene, di Vinylbenzene, and the like. Among these, styrene is preferable from the viewpoint of industrial availability. These may use not only 1 type but 2 types or more together.

When the conjugated diene polymer used for this embodiment is a copolymer, a random copolymer may be sufficient and a block copolymer may be sufficient.

Although it does not specifically limit as a random copolymer, For example, butadiene-isoprene random copolymer, butadiene-styrene random copolymer, isoprene-styrene random copolymer, butadiene-isoprene-styrene random copolymer, etc. are mentioned. Although the composition distribution of each monomer in a copolymer chain is not specifically limited, For example, the fully random copolymer near a statistically random composition, the taper (gradient) random copolymer which has a gradient in composition distribution, etc. are mentioned. The composition of the conjugated diene, that is, the composition of the 1,4-bond or 1,2-bond, may be uniform or different depending on the molecular chain.

Although it does not specifically limit as a block copolymer, For example, the 2 type block copolymer containing 2 blocks, the 3 type block copolymer containing 3, the 4 type block copolymer containing 4, etc. are mentioned. A block containing an aromatic vinyl compound such as styrene is represented by S, and a block containing a conjugated diene compound such as butadiene or isoprene and / or a block containing a copolymer of an aromatic vinyl compound and a conjugated diene compound is represented by B. SB type 2 block copolymer, SBS type 3 block copolymer, SBSB type 4 block copolymer, etc. are represented.

In the above formula, the boundary of each block does not necessarily need to be clearly distinguished. For example, when block B is a copolymer of an aromatic vinyl compound and a conjugated diene compound, the aromatic vinyl compound in block B may be distributed uniformly, or may be distributed in the taper shape. In the block B, a plurality of portions in which the aromatic vinyl compound is uniformly distributed and / or a portion in a tapered shape may coexist. Furthermore, in the block B, a plurality of segments having different aromatic vinyl compound contents may coexist. When two or more blocks S and B exist in a copolymer, structures, such as those of molecular weight and a composition, may be the same and may differ.

In the present embodiment, the weight average molecular weight of the conjugated diene polymer is preferably 300,000 to 2 million, more preferably 800,000 or more from the viewpoint of wear resistance of the tire, and 180 from the viewpoint of processability when processing into a tire. It is preferable that it is ten thousand or less.

In this embodiment, it is preferable that a conjugated diene polymer contains a high molecular weight component from a viewpoint of the strength and abrasion resistance of a silica compounding vulcanizate. As an example of the index of a high molecular weight component, when expressed by the composition of the component of 1 million or more molecular weight, it is preferable that it is 30-95 mass% of components with a molecular weight of 1 million or more, More preferably, it is 30-90 mass%, More preferably, It is 40-90 mass%. If it is 30 mass% or more, it is excellent in abrasion resistance, and when it is 95 mass% or less, since the dispersibility of a silica is good when mixing a conjugated diene polymer and a silica, it is excellent in the fuel efficiency saving and grip property at the time of making a tire product. When a high molecular weight component exists in the said composition range, peeling of a crumb tends to occur easily and swelling of a bale tends to occur, and the meaning which makes the specific surface area of a bale into a specific range becomes further high.

Polymerization of Conjugated Diene Polymer

The initiator for polymerizing the conjugated diene or aromatic vinyl is not particularly limited as long as it is an anionic polymerization initiator. From the standpoint of stability and handleability, for example, alkyl compounds of metals such as aluminum, magnesium, lithium, sodium, potassium and the like are preferable. In particular, organolithium is particularly preferable from the viewpoint of polymerization efficiency. Although it does not restrict | limit especially as organolithium used as a polymerization initiator, For example, the organolithium of a low molecular weight compound and a solubilized oligomer is mentioned, In addition, in the bonding mode of an organic group and lithium, although it does not restrict | limit in particular, For example, the compound containing a carbon-lithium bond, the compound containing a nitrogen-lithium bond, the compound containing a tin-lithium bond, etc. are mentioned.

Although it does not restrict | limit especially as organolithium which has a carbon-lithium bond, For example, n-butyllithium, sec-butyllithium, tert- butyllithium, n-hexyl lithium, benzyl lithium, phenyl lithium, stilben lithium, etc. are mentioned. Can be.

The organolithium containing a nitrogen-lithium bond is not particularly limited, but for example, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium di-n-hexylamide, lithium diisopropylamide, lithium hexamethylene And imides, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, and lithium morpholide.

As organic lithium, not only said mono organolithium but polyfunctional organolithium can be used, or it can also superpose | polymerize in combination with mono organolithium.

The polyfunctional organolithium is not particularly limited, but for example, 1,4-dirithiobutane, a reactant of sec-butyllithium and diisopropenylbenzene, 1,3,5-tririthiobenzene, n-butyllithium And a reactant of 1,3-butadiene and divinylbenzene, and a reactant of n-butyllithium and a polyacetylene compound. In addition, organic lithium disclosed in US Pat. No. 5,708,092, British Pat. No. 2,241,239, US Pat. No. 5,527,753, or the like may also be used. As organic lithium, n-butyllithium and sec-butyllithium are preferable from the viewpoint of the industrial availability and the control of the polymerization reaction.

You may use organolithium as a mixture not only 1 type but 2 types or more.

In fact, when using organolithium for superposition | polymerization, in order to improve handleability and dispersibility with respect to superposition | polymerization solution, what diluted with the hydrocarbon solvent and used as the solution is used. Although it does not restrict | limit especially as an example of a hydrocarbon solvent, C4-C8 hydrocarbon solvent is mentioned, It may be cyclic and may contain an unsaturated bond and a branched structure (toluene, xylene, etc.). C5 and C6 are preferable at the point which a boiling point and vapor pressure are easy to handle in a manufacturing process, and pentane, normal hexane, and cyclohexane are specifically used.

It is preferable that the density | concentration at the time of diluting organolithium in the said hydrocarbon is 0.01 mass%-1 mass% from a viewpoint of superposition | polymerization initiation efficiency and the homogeneous mixing property of a monomer, Especially preferably, it is 0.1 mass%-0.8 mass%. to be.

It is preferable to perform the polymerization reaction of a conjugated diene compound in a solvent. Although it does not restrict | limit especially as a solvent, For example, hydrocarbon type solvents, such as a saturated hydrocarbon and an aromatic hydrocarbon, are mentioned. Specifically, alicyclic hydrocarbon mixtures such as butane, pentane, normal hexane, isohexane, heptane, cyclopentane, cyclohexane, methylcyclopentane and methylcyclohexane are preferable. Although these may be individual or may be used together 2 or more types, it is more preferable that it is a mixed solvent containing normal hexane from a viewpoint of making a particle diameter of the copolymer after a desolvent small, and from a viewpoint of preventing scaling in a polymerization tank, normal hexane and isohexane , A mixed solvent of cyclohexane is particularly preferred. In the case of a mixed solvent, 20-80 mass% is preferable, as for the ratio of normal hexane, 30-70 mass% is more preferable, 40-65 mass% is especially preferable. If the ratio of normal hexane is 20 mass% or more, since the amount of residual solvent after a desolvent can be reduced, it is good because scaling of a polymerization tank can be prevented if the ratio of normal hexane is 80 mass% or less.

If an allene or acetylene, which is an impurity, is treated with an organometallic compound before providing it to the polymerization reaction, a polymer having a high concentration of active terminals tends to be obtained, and a high modification rate tends to be achieved when the modification reaction is carried out after polymerization. It is preferable because there is.

In the polymerization reaction of a conjugated diene compound, you may add a polar compound. The polar compound can be used to randomly copolymerize the aromatic vinyl compound with the conjugated diene compound, and can also be used as a vinylating agent for controlling the microstructure of the conjugated diene portion. It is also effective in improving the polymerization rate and the like.

It does not specifically limit as a polar compound, For example, tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, dimethoxybenzene, Ethers such as 2,2-bis (2-oxolanyl) propane; Tertiary amine compounds such as tetramethylethylenediamine, dipiperidinoethane, trimethylamine, triethylamine, pyridine and quinuclidin; Alkali metal alkoxide compounds such as potassium-t-amylate, potassium-t-butyrate, sodium-t-butyrate, and sodium amylate; Phosphine compounds such as triphenylphosphine and the like can be used. These polar compounds may be used independently, respectively and may be used in combination of 2 or more type.

The usage-amount of a polar compound is not specifically limited, It can select according to the objective etc .. Usually, it is preferable that it is 0.01-100 mol with respect to 1 mol of polymerization initiators. Such a polar compound (vinylating agent) is a regulator of the microstructure of the polymer conjugated diene moiety, and may be appropriately used depending on the desired amount of vinyl bonds.

Many polar compounds have an effective randomization effect in the copolymerization of a conjugated diene compound and an aromatic vinyl compound, and can be used as an agent for adjusting the distribution of an aromatic vinyl compound and the amount of styrene blocks. As a method for randomizing a conjugated diene compound and an aromatic vinyl compound, a method of intermittently adding a part of 1,3-butadiene during the copolymerization, as described, for example, in JP-A-59-140211 You may use it.

The polymerization temperature is not particularly limited as long as it is a temperature at which polymerization proceeds. From the viewpoint of productivity, the polymerization temperature is preferably 0 ° C. or more, and preferably 120 ° C. or less from the viewpoint of suppressing deactivation during polymerization. Moreover, you may use polyfunctional aromatic vinyl compounds, such as divinylbenzene, for controlling a branch from a viewpoint of preventing the cold flow of a conjugated diene polymer.

Although the process of a polymerization reaction may be any of batch type, semi-batch type, and continuous type, when it is continuous type, since molecular weight distribution is generally large and a high molecular weight component is also easy to be obtained, it is preferable.

You may add a deactivator, a neutralizing agent, etc. to a reaction solution as needed. As a deactivator, it does not specifically limit, For example, Water; Alcohol, such as methanol, ethanol, and isopropanol, etc. are mentioned. As a neutralizing agent, it does not specifically limit, For example, carboxylic acid, such as stearic acid, oleic acid, and versaic acid, the aqueous solution of an inorganic acid, a carbon dioxide gas, etc. are mentioned.

Moreover, it is preferable to add the stabilizer for rubber | gum with respect to the obtained conjugated diene polymer from a viewpoint of preventing the gel formation after superposition | polymerization, or improving the stability at the time of processing. The stabilizer for rubber is not particularly limited and known ones can be used. Examples thereof include 2,6-di-tert-butyl-4-hydroxytoluene (BHT) and n-octadecyl-3- (4'-hydride. Antioxidants, such as oxy-3 ', 5'- di-tert- butylphenol) propionate and 2-methyl-4, 6-bis [(octylthio) methyl] phenol, are preferable.

After obtaining the conjugated diene polymer by the method as described above, at least one selected from an epoxy group, an alcohol group, an amino group, an isocyanate group, a cyanurate group, a silanol group, and an alkoxyl group bonded to silicon at the active end of the conjugated diene polymer When reacting the compound which has a functional group, the conjugated diene polymer may be modified, and when it uses for the composition containing silica to modify | modify to the compound which has at least 1 functional group selected from an epoxy group, a silanol group, or the alkoxyl group couple | bonded with the silicon. In view of silica dispersibility, it is preferable.

It does not specifically limit as a compound which has an epoxy group, For example, polyglycidyl ether of polyhydric alcohols, such as ethylene glycol diglycidyl ether and glycerine triglycidyl ether, and 4,4'- diglycidyl bisphenol A Polyglycidyl ethers of aromatic compounds having two or more phenol groups such as these; Poly epoxy compounds such as 1,4-diglycidylbenzene, 1,3,5-triglycidylbenzene, and polyepoxidized liquid polybutadiene; Epoxy group-containing tertiary amines such as 4,4'-diglycidyl-diphenylmethylamine and 4,4'-diglycidyl-dibenzylmethylamine; Diglycidyl aniline, diglycidyl ortho toluidine, tetraglycidyl methaxylenediamine, tetraglycidylaminodiphenylmethane, tetraglycidyl-p-phenylenediamine, diglycidylaminomethylcyclohexane, And diglycidylamino compounds such as tetraglycidyl-1,3-bisaminomethylcyclohexane and tetraglycidyl-1,3-bisaminomethylcyclopentane. Among these, the polyfunctional compound which has a diglycidyl amino group is preferable. Moreover, the number of epoxy groups in a molecule | numerator of the polyfunctional compound which has a diglycidyl amino group is two or more, Preferably it is three or more, More preferably, it is four or more.

As a modifier which has a silanol group and / or the alkoxyl group couple | bonded with the silicon, it does not specifically limit, For example, the compound represented by following General formula (1) is mentioned.

(Wherein, X is selected from any one of Cl, Br, I, R ¹ and R ² are each independently any of an alkyl group, an aryl group, a vinyl group, m is an integer of 1 to 4, n is 1 to An integer of 3, m + n is 2 to 4)

In addition, R ¹ and R ² may be substituted.

As a specific example of the compound represented by General formula (1), it does not specifically limit, For example, dimethoxydimethylsilane, diethoxydiethylsilane, triphenoxy vinylsilane, trimethoxy vinylsilane, triethoxy vinylsilane, Tri (2-methylbutoxy) ethylsilane, tri (2-methylbutoxy) vinylsilane, triphenoxyphenylsilane, tetraphenoxysilane, tetraethoxysilane, tetramethoxysilane, tetrakis (2-ethylhex Siloxy) silane, phenoxydivinylchlorosilane, methoxydiethylchlorosilane, diphenoxymethylchlorosilane, diphenoxyphenyliodosilane, diethoxymethylchlorosilane, dimethoxyethylchlorosilane, triethoxychlorosilane, Triphenoxycyclolosilane, tris (2-ethylhexyloxy) chlorosilane, phenoxymethyldichlorosilane, methoxyethyldichlorosilane, ethoxymethyldichlorosilane, phenoxyphenyldiiodosilane, phenoxydichlorosilane, dimeth Methoxydichloro Column, and the like can be mentioned bis (2-methyl-butoxy) di-bromo mosilran.

Moreover, as a modifier which has an alkoxy silyl group, it is preferable to use the compound represented by General formula (2) or (3) which has N atom and several alkoxy silyl groups in a molecule | numerator.

(In formula (2), R <^1> -R <^4> represents a C1-C20 alkyl group or an aryl group each independently, R <^5> represents a C1-C10 alkylene group, and R <^6> is C1-C20 An alkylene group, m is an integer of 1 or 2, n is an integer of 2 or 3.)

(In formula (3), R <^1> and R <^2> is a C1-C20 alkyl group or an aryl group each independently, R <^3> is a C1-C20 alkylene group, R <^4> and R <^5> is respectively independent Is a hydrocarbon group of 1 to 6 carbon atoms, and together with two adjacent N, form a ring structure of 5 or more rings, R ⁶ is a hydrocarbon group of 1 to 20 carbon atoms, substituted with a hetero atom having no active hydrogen, 1 to 20 carbon atoms Is a hydrocarbon group or a 3 organic substituted silyl group, and n is an integer of 2 or 3.

In addition, R ¹ to R ⁶ may be substituted.

The modifier represented by the general formula (2) is not particularly limited and is, for example, 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2 -Diethoxy-1- (3-triethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-dimethoxy-1- (4-trimethoxysilylbutyl) -1-aza-2 -Silacyclohexane, 2,2-dimethoxy-1- (5-trimethoxysilylpentyl) -1-aza-2-silacycloheptane, 2,2-dimethoxy-1- (3-dimethoxymethylsilyl Propyl) -1-aza-2-silacyclopentane, 2,2-diethoxy-1- (3-diethoxyethylsilylpropyl) -1-aza-2-silacyclopentane, 2-methoxy, 2-methyl -1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-triethoxysilylpropyl) -1-aza-2- Silacyclopentane, 2-methoxy, 2-methyl-1- (3-dimethoxymethylsilylpropyl) -1-aza-2-silacyclopentane, 2-ethoxy, 2-ethyl-1- (3-die Methoxyethylsilylpropyl) -1-aza-2-silacyclopentane, etc. The can. Among these, it is preferable that m is 2 and n is 3 from a viewpoint of the reactivity and interactivity of the functional group of a modifier and inorganic fillers, such as silica, and a tensile characteristic. Specifically, 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane, 2,2-diethoxy-1- (3-triethoxysilylpropyl ) -1-aza-2-silacyclopentane is preferred.

As a modifier represented by General formula (3), it does not specifically limit, For example, 1- [3- (trialkoxysilyl) -propyl] -4-alkyl piperazine, 1- [3- (alkyldialkoxysilyl) -propyl ] -4-alkylpiperazine, 1- [3- (trialkoxysilyl) -propyl] -3-alkylimidazolidine, 1- [3- (alkyldialkoxysilyl) -propyl] -3-alkylimida Zolidine, 1- [3- (trialkoxysilyl) -propyl] -3-alkylhexahydropyrimidine, 1- [3- (alkyldialkoxysilyl) -propyl] -3-alkylhexahydropyrimidine, 3- [3- (trialkoxysilyl) -propyl] -1-alkyl-1,2,3,4-tetrahydropyrimidine, 3- [3- (alkyldialkoxysilyl) -propyl] -1-alkyl-1, 2,3,4-tetrahydropyrimidine etc., and the following compounds are mentioned specifically ,.

1- [3- (triethoxysilyl) -propyl] -4-methylpiperazine, 1- [3- (diethoxyethylsilyl) -propyl] -4-methylpiperazine, 1- [3- ( Trimethoxysilyl) -propyl] -3-methylimidazolidine, 1- [3- (diethoxyethylsilyl) -propyl] -3-ethylimidazolidine, 1- [3- (triethoxysilyl ) -Propyl] -3-methylhexahydropyrimidine, 1- [3- (dimethoxymethylsilyl) -propyl] -3-methylhexahydropyrimidine, 3- [3- (tributoxysilyl) -propyl] -1-methyl-1,2,3,4-tetrahydropyrimidine, 3- [3- (dimethoxymethylsilyl) -propyl] -1-ethyl-1,2,3,4-tetrahydropyrimidine, 1- (2-Ethoxyethyl) -3- [3- (trimethoxysilyl) -propyl] -imidazolidine, (2- {3- [3- (trimethoxysilyl) -propyl] -tetra Hydropyrimidin-1-yl} -ethyl) dimethylamine and the like. Preferable compound is 1- [3- (triethoxysilyl) -propyl] -4-methylpiperazine.

The crumb of the conjugated diene polymer can be obtained by, for example, desolventing a solution of the conjugated diene polymer.

Although it does not specifically limit as a method of desolvent, For example, it removes, conveying by the steam stripping method disclosed by the international publication WO2013-080969 specification, the flash evaporation method disclosed by Unexamined-Japanese-Patent No. 6-93014, and a biaxial screw. The method of solvent, etc. are mentioned.

Process oil may be added to the conjugated diene polymer to form a dielectric conjugated diene polymer. Process oils are not particularly limited, but, for example, aromatic, naphthenic, paraffinic RAE (Residual Aromatic Extracts), MES (Mild Extracted Solvates), and TDAE (Process Distillation). Aromatic extracts (Treated Distilled Aromatic Extracts), among which TDAE is preferred in view of moldability and vulcanizability of the silica compound.

It is preferable that the addition amount of a process oil is 1-50 mass parts with respect to 100 mass parts of conjugated diene polymers, It is more preferable that it is 1-30 mass parts, It is more preferable that it is 5-30 mass parts, It is especially preferable that it is 5-20 mass parts. Do. When the addition amount of process oil is 1 mass part or more and the specific surface area of a conjugated diene polymer can be controlled, generation | occurrence | production of fine powder can be suppressed, and if the addition amount of process oil is 50 mass parts or less, solvent resistance is good.

The process oil may be mixed before desolventing the solution of the conjugated diene polymer, or kneaded and mixed after desolventing.

The residual volatile matter contained in the crumb of the conjugated diene polymer after the desolvent is preferably 100 to 10,000 ppm, more preferably 200 to 7,000 ppm, particularly preferably 500 to 5,000 ppm. When the residual volatile matter is 10,000 ppm or less, the amount of gas generated in the bale forming step is small, which is preferable in the working environment. When the residual volatile matter is 100 ppm or more, the scattering of the rubber powder is small. Residual volatile component here refers to the water used at the hexane used in the manufacturing process of a conjugated diene polymer, or a desolvent process.

The method for adjusting the residual volatile matter is not particularly limited, but in the case of the steam stripping method, for example, a method of adjusting the temperature or amount of steam brought into contact with the conjugated diene polymer, a method of adding a surfactant to the steam, steam and The method of adjusting the shape and rotation speed of the rotary blade used when mixing a conjugated diene polymer is mentioned, Especially, the method of adjusting the temperature of steam is simple and effective. When the residual volatile content exceeds 10,000 ppm, it is possible to adjust to 10,000 ppm or less by increasing the steam temperature, and when the residual solvent is less than 100 ppm, it can be adjusted to 100 ppm or more by lowering the steam temperature. When desolventing while conveying with a biaxial screw, the method of adjusting the heating temperature conditions of a biaxial screw apparatus is simple and effective. When the residual volatile content exceeds 10,000 ppm, it is possible to adjust to 10,000 ppm or less by increasing the heating temperature, and when the residual solvent is less than 100 ppm, it can be adjusted to 100 ppm or more by lowering the heating temperature.

The crumb particle diameter of the conjugated diene polymer after the desolvent is preferably 0.1 to 20 mm, and is preferably 0.5 to 15 mm from the viewpoint of handleability. If the crumb particle size of the conjugated diene polymer is 0.1 mm or more, there is little crumb peeled from the bale. If the crumb particle size of the conjugated diene polymer is 20 mm or less, the swelling of the bale is suppressed after the bale molding.

As a method of adjusting the crumb particle diameter of a conjugated diene polymer, the polymer solution obtained after superposition | polymerization may be adjusted in the process of desolvating and manufacturing a crumb, and the manufactured crumb may be processed and adjusted. When adjusting in the process of manufacturing a crumb by desolvent, it does not specifically limit, For example, the method of adjusting the quantity of the process oil added to a polymer solution, the method of adjusting the die-hole diameter of a dry extruder, a polymer solution The method of adjusting the conditions at the time of adding to a hot water and removing a solvent is mentioned. In the case where the latter manufactured crumb is processed and adjusted, the crumb is not particularly limited, and examples thereof include a method of sifting the crumb and a method of pulverizing and crushing the crumb with a mixer or granulator.

The specific surface area of the crumb of the conjugated diene polymer of this embodiment is 0.7-3.2 m <2> / g, More preferably, it is 1.0-3.0 m <2> / g from a viewpoint of handleability. If the specific surface area of the crumb of the conjugated diene polymer is 0.7 m 2 / g or more, the area where one crumb is in close contact with the surrounding crumb also increases when the crumb is formed into a bale, so that the crumb becomes difficult to peel off from the bale. If the specific surface area of the crumb of the conjugated diene polymer is 3.2 m 2 / g or less, the crumb particles are compressed to a higher density at the time of being molded into the bale, so that the voids between the crumbs are also suppressed, thereby suppressing the swelling of the bale.

Although it does not specifically limit as a method of adjusting the specific surface area of the crumb of a conjugated diene polymer to the said range, For example, the method of sifting the crumb of a conjugated diene polymer, and adjusting the composition of each sieved crumb is mentioned. .

The manufacturing method of the bale of this embodiment includes the process of producing the crumb of the conjugated diene polymer whose specific surface area is 0.7 m <2> / g-3.2 m <2> / g, and obtaining a bale by compression molding the said crumb. Moreover, it is preferable that the manufacturing method of the bale of this embodiment further has the process of sifting the crumb of the said conjugated diene polymer.

When the crumb of the conjugated diene polymer is compression-molded, the crumb may be in close contact with each other, so that the specific surface area of the bale is lower than the specific surface area of the crumb. The adhesion of the crumb during compression molding can be adjusted by the molecular weight of the conjugated diene polymer, the process oil composition, the temperature at the time of compression, and the pressure. For example, in order to increase the adhesion of the crumb to lower the specific surface area of the bale, Conditions for lowering the molecular weight of the conjugated diene polymer, increasing the composition of the process oil, or increasing both the temperature and pressure during compression are preferred.

The veil specific surface area of this embodiment is 0.005-0.05 m <2> / g, More preferably, it is 0.01-0.04 m <2> / g from a film packaging property viewpoint. If the specific surface area of the bale is 0.005 m 2 / g or more, the expansion of the bale is suppressed, and if the specific surface area of the bale is 0.05 m 2 / g or less, peeling of the crumb from the bale is preferable.

The specific surface area of the crumb and veil of a conjugated diene polymer can be calculated | required by the BET method. Nitrogen and krypton gas can be used for the adsorbate. If krypton gas is used in the region having a specific surface area of less than 0.1, the measurement accuracy is good, which is preferable.

The specific surface area of the bale may vary depending on the area of the bale, and among them, the one with high correlation with the bale expandability and crumb detachability has a specific surface area near the center of the bale, so the sample used for measuring the specific surface area is also near the center of the bale. It is preferable to collect from the. Here, the vicinity of the center portion is a position where the sum of the distances from each side of the bale is the largest.

The crumb used for baling may be used as it is, if the specific surface area of the molded bale is cut into the above range, but the crumb after the solvent may be used as it is.

If the specific surface area of the bale formed by using the crumb after the desolvent exceeds the upper limit of the above range, the crumb of the sifted fraction may be increased to increase the crumb composition of the large particle size and reduce the crumb composition of the small particle diameter, and may not reach the lower limit. If not, it is possible to reduce the crumb composition of the large particle size and increase the crumb of the small particle size.

For example, a crumb after a desolvent having a weight average molecular weight of 1 million parts by weight of a conjugated diene polymer and 10 parts by mass of a process oil composition is formed into a metal mesh having an eye size of 0.5 mm, 3.4 mm, 4.0 mm, 6.7 mm, 8.0 mm, and 9.5 mm. 0.5 mm mesh when the crumb mass composition remaining in each metal mesh at the time of sifting is 30, 10, 10, 20, 20, 10 mass parts, respectively, and the specific surface area of a bale was 0.004-0.0048 m <2> / g The specific surface area of the bale can be set to 0.030 to 0.038 m 2 / g by reducing the crumb to 10 parts by mass and increasing the crumb of the 3.4 mm metal mesh to 20 parts by mass and the 20 part by mass of the 4.0 mm crumb.

Although sieving of crumb is not specifically limited, For example, it can carry out according to "JISZ8815: 1994 sieve classification test method general rule." Sieve classification is performed using a plurality of sieves with different eye sizes, of which the smallest eye size does not pass even at the minimum crumb size, and the largest eye size is smaller than the maximum crumb size. What is necessary is just to select and it is preferable to insert the sieve of at least 3 different eye size between the said maximum eye size and the minimum eye size, since the control precision of a veil specific surface area becomes high.

The compression pressure at the time of bal forming is preferably 3 to 30 MPa, more preferably 10 to 20 MPa. If the compression pressure at the time of bal forming is 30 Mpa or less, an apparatus can be designed compactly, and installation efficiency is good, and if the compression pressure at the time of bail shaping is 3 MPa or more, the bail formability is favorable. When the formability of the bale is good, the surface of the bale is smooth, there is no peeling of the polymer after the forming step, and there is a tendency that expansion after molding is suppressed.

30-120 degreeC is preferable and, as for the temperature of the conjugated diene polymer at the time of veil shaping, More preferably, it is 50-100 degreeC from a viewpoint of residual solvent reduction and thermal degradation suppression. If the temperature of the conjugated diene polymer at the time of bal forming is 30 degreeC or more, the moldability of a bale is good, and if the temperature of the conjugated diene polymer at the time of bale forming is 120 degrees C or less, since gel formation by the thermal deterioration after bail shaping | molding is suppressed, it is preferable. Do.

If the molecular weight of the conjugated diene polymer and the composition of the process oil are the same, the higher the temperature and pressure at the time of forming the bale, the smaller the specific surface area of the bale.

The pressure holding time at the time of compression becomes like this. Preferably it is 3 to 30 second, More preferably, it is 5 to 20 second. If the pressure holding time at the time of compression is 30 seconds or less, productive efficiency will be good, and if it is 5 seconds or more, moldability will be good.

The bale may be packaged with a resin film in order to avoid adhesion between the molded bodies. It does not specifically limit as resin of the said film, For example, PET, polyethylene, polystyrene can be used.

The bale is stored in a container for transportation. The storage property in a container is good in it being preferable that the veil expansion rate after 1 day after shaping | molding is less than 5%.

In order to prevent the moisture of the bale from condensing on the resin film during transportation, a hole may be punched in the film.

The conjugated diene polymer is blended with other rubber materials such as natural rubber, inorganic materials such as silica and carbon, and the like and processed into tires, various industrial belts, shoes and the like.

EXAMPLE

The present invention will be described in more detail with reference to the following examples. In addition, this invention is not limited at all by the following example and a comparative example, unless the summary is exceeded.

(1) amount of bound styrene

100 ml of the solution was sampled from the polymerization solution extruded from the polymerization reactor, 1 ml of ethanol was added and mixed therein, the active terminal of the polymer molecular chain was inactivated, and the polymer solution was obtained. Next, the solvent was removed from the polymer solution using the vacuum dryer, and the solid sample used for the measurement was produced. Chloroform was added to the solid sample, and it was set as the chloroform solution, and the binding styrene amount (mass%) was measured by absorption of UV254nm by the phenyl group of styrene using this chloroform solution (made by Shimadzu Corporation) UV-2450.

(2) vinyl bond amount of butadiene part

The solid sample obtained by performing the same operation as the above (1) was dissolved in 10 mL of carbon disulfide to prepare a solution cell. Using the solution cell, the infrared spectrum in the range of 600-1000 cm <^-1> was measured using the infrared spectrophotometer (brand name "FT-IR230" by the Nippon Bunko company). From the resulting absorbance, the microstructure of the butadiene moiety, that is, the amount of vinyl bonds (mol%), was determined according to Hampton's method calculation formula (RRHampton, Analytical Chemistry 21,923 (1949)).

(3) molecular weight and molecular weight distribution

The calibration curve was created from the measurement result of standard polystyrene which measured the chromatogram of a sample and standard polystyrene using GPC using the column which used the polystyrene gel as a filler, and calculated molecular weight and molecular weight distribution by this. Tetrahydrofuran (THF) was used as the eluent. 10 mg of sample was dissolved in 20 ml of THF, which was measured by injecting into a 200 μl column. The measurement was carried out in an oven temperature of 40 ° C., under conditions of a flow rate of 1.0 ml / min of THF; It was performed using HLC8020 (detector; RI).

(4) Measurement of specific surface area

Specific surface area was calculated | required by BET. That is, the specific surface area was calculated | required by measuring the adsorption | release adsorption isotherm by krypton gas after vacuum- devolatilizing a sample at 25 degreeC for 8 hours.

In the case of a veil, the site | part vicinity of the center part evenly separated from each surface of the rectangular parallelepiped was used for the measurement sample.

(5) veil expansion rate

The bale expansion rate was calculated | required from following formula (1) from the veil volume (V0) m <3> immediately after shaping | molding, and the veil volume (V1) m <3> after 1 day progression.

Veil expansion rate (%) = 100 × {(V1) − (V0)} / (V0)... (One)

In view of the storage properties when the bale is stored in the metal container, the bale expansion ratio is preferably less than 5%.

(6) crumb peel test

The amount of crumb of the conjugated diene polymer peeled off from the bale molded body was determined by the bale drop test. Specifically, the amount of crumb of the conjugated diene polymer peeled off from the bale was measured when the bale dropped from the height of 100 cm vertically to the concrete floor. The smaller the amount of crumbs of the conjugated diene polymer is, the smaller the amount of crumbs of the polymer peeled off from the bale after the molding process of the actual manufacturing process is preferable, and if the amount is less than 0.2% by mass of the total amount of the bale, it is preferable. .

(Preparation Example 1 of Solution of Dielectric Conjugated Diene Polymer A)

Four 10 L reactors with stirring blades of paddles (L / D = 4 as a ratio of the length L of the reactor to the diameter D of the reactor) are placed in series and the first stage is the polymerization reactor, 2 The stage was used as a modification reactor. 1,3-butadiene, which has previously removed impurities such as water, is mixed with 22.0 g / min, styrene 7.1 g / min, and n-hexane under conditions of 144 g / min. Immediately before, 0.10 mmol / min of n-butyllithium (treatment n-butyllithium) was mixed with a static mixer and then fed continuously to the bottom of the polymerization reactor. Further, 2,2-bis (2-oxolanyl) propane as a polar substance was supplied at a rate of 0.040 g / min, n-butyllithium as a polymerization initiator at a rate of 0.180 mmol / min, and supplied to the bottom of the polymerization reactor. The polymerization reaction was continued so that the internal temperature of the reactor outlet was 90 ° C. The polymerization solution extruded from the first polymerization reactor was directly supplied to the second reactor.

Conjugated diene polymer by maintaining the temperature of the modification reactor at 85 ° C. and carrying out the modification reaction by adding tetraglycidyl-1,3-bisaminomethylcyclohexane from the bottom of the modification reactor at a rate of 0.35 mmol / min as a modifier. The solution of A was extruded from the denaturation reactor. To this was added TDAE oil (VIVATEC500) to obtain a solution of dielectric conjugated diene polymer A.

As a result of analyzing the conjugated diene polymer A, it was found that the amount of bound styrene was 24% by mass, the amount of bound butadiene was 76% by mass, and the amount of vinyl bonds in butadiene was 65 mol%, the weight average molecular weight (Mw) was 1,500,000, and the composition having a molecular weight of 1 million or more was 45. It was mass%.

(Production Example 2 of Solution of Dielectric Conjugated Diene Polymer B)

Oil is modified except that the modifier is 2,2-dimethoxy-1- (3-trimethoxysilylpropyl) -1-aza-2-silacyclopentane instead of tetraglycidyl-1,3-bisaminomethylcyclohexane. The solution of the conjugated diene polymer B was obtained like Example 1 of the solution of the conjugated diene polymer A. A desired amount of TDAE oil (VIVATEC500) was added to the solution extruded from the reactor outlet to obtain a solution of dielectric conjugated diene polymer B.

As a result of analyzing the conjugated diene polymer B, it was found that the amount of bound styrene was 24% by mass, the amount of bound butadiene was 76% by mass, and the amount of vinyl bonds in butadiene was 65 mol%, the weight average molecular weight (Mw) was 1.3 million, and the composition having a molecular weight of 1 million or more was 70. It was mass%.

[Crum production example 1 of conjugated diene polymer]

In a twin screw extruder having a screw diameter of 50 mm and L / D = 10, a solution of the conjugated diene polymer was continuously supplied at a rate of 5 kg per hour from the supply port. The solution of the conjugated diene polymer was heated while feeding the heat medium oil of 180 degreeC to the jacket of a twin screw extruder. The vent port was connected to a vacuum pump through a pipe, and the apparatus inside was maintained at 100 torr. The conjugated diene polymer (polymer) solution was desolvated in the extruder. The conjugated diene polymer obtained by desolvent was discharged as a particulate (crude) to the tank connected to the twin screw extruder discharge port.

[Crum production example 2 of conjugated diene polymer]

5 L of hot water at 80 ° C. was placed in a 10 L container, and the solution of the conjugated diene polymer was added dropwise at a rate of 100 g per minute for 30 minutes while stirring with a paddle-shaped stirring blade, and then the solvent was removed by continuing stirring for 30 minutes after completion of dropping. . The crumb of the conjugated diene polymer was obtained by drying the crumb of the conjugated diene polymer produced in hot water.

[Adjustment method of bale crumb]

It carried out according to JISZ8815: 1994 General Classification Test. The crumb after the desolvent was sifted into a metal mesh having a diameter of 200 mm, an eye size of 0.5 mm, 3.4 mm, 4.0 mm, 6.7 mm, 8.0 mm, and 9.5 mm, and the conjugated diene polymer crumb remaining in each metal mesh was fractionated. Here, for example, the crumb left in the metal mesh of an eye size of 4.0 mm passes through the metal mesh of an eye size of 6.7 mm, but does not pass through the metal mesh of 4.0 mm, which is called 4.0 mm crumb. The crumbs remaining in the metal mesh of other eye size are likewise referred to as 0.5 mm crumbs, 3.4 mm crumbs, 6.7 mm crumbs, 8.0 mm crumbs, and 9.5 mm crumbs. The crumb separated by these sieves was mixed uniformly at arbitrary blending ratios, and the bale crumb was adjusted.

[Manufacturing method of a veil]

A cuboid container with a long side 420 mm, a short side 210 mm, and a depth of 400 mm was filled with a crumb adjusted by the above method after heating to 60 ° C., and a pressure of 3.5 MPa was compressed in a cylinder for 10 seconds.

EXAMPLE 1

The solvent was removed in accordance with Preparation Example 1 of the crumb using a solution of the dielectric conjugated diene polymer A to obtain a crumb. The addition amount of TDAE oil was 20 mass parts with respect to 100 mass parts of conjugated diene polymers. According to the said crumb particle size control method, the crumb used for bale shaping | mixing was mix | blended and adjusted. The compounding composition is 10% by mass of 0.5mm crumb, 20% by mass of 3.4mm crumb, 20% by mass of 4.0mm crumb, 20% by mass of 6.7mm crumb, 20% by mass of 8.0mm crumb, and 10% of 9.5mm crumb. It was made into%. The specific surface area of the bale crumb was 1.72 m 2 / g. According to the manufacturing method of the said bale, the bale of the weight of a rectangular parallelepiped 6kg was obtained using the adjusted bale crumb. The dimension of the obtained veil was 420 mm long side 210 mm x side 88 mm high. It was 0.020 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.60 g and was 0.010 mass% with respect to the bale whole quantity. After one day, the sides of the bale were measured and the expansion ratio was found to be 3.3%.

EXAMPLE 2

Except having made the addition amount of TDAE oil into 10 mass parts with respect to 100 mass parts of conjugated diene polymers, it carried out similarly to Example 1, and obtained the veil of the weight of a rectangular parallelepiped 6 kg. The specific surface area of the bale crumb was 1.77 m 2 / g. The size of the molded bale was 420 mm long side 210 mm short side 90 mm high. It was 0.037m <2> / g as the specific surface area was measured by cutting out the vicinity of the bale center part. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.96 g, and was 0.016 mass% with respect to the bale whole quantity. After one day, the sides of the bale were measured to obtain an expansion ratio, which was less than 1%.

EXAMPLE 3

Except having performed the desolvent according to manufacture example 2 of a crumb, it carried out similarly to Example 1 and obtained the veil of the weight of a rectangular parallelepiped 6 kg. The specific surface area of the bale crumb was 1.84 m 2 / g, and the size of the molded bale was 420 mm long side 210 mm short side side 88 mm high. It was 0.019 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.582 g, and was 0.0097 mass% with respect to the bale whole quantity. After one day, the veil angle was measured and the volume was calculated. As a result, the expansion ratio was 3.5%.

EXAMPLE 4

Except having made the addition amount of TDAE oil 10 mass parts with respect to 100 mass parts of conjugated diene polymers, it carried out similarly to Example 3, and obtained the veil of the weight of a rectangular parallelepiped 6 kg. The specific surface area of the bale crumb was 1.70 m 2 / g, and the size of the formed bale was 420 mm long side 210 mm short side 210 mm high. It was 0.041m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 1.02 g, and was 0.017 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

[Example 5]

A solution of the dielectric conjugated diene polymer B was used instead of the solution of the dielectric conjugated diene polymer A, and the weight of the rectangular parallelepiped was carried out in the same manner as in Example 1 except that the amount of TDAE oil was 15 parts by mass based on 100 parts by mass of the conjugated diene polymer. 6 kg of bales were obtained. The specific surface area of the bale crumb was 1.76 m 2 / g, and the size of the molded bale was 420 mm long side 210 mm short side 210 mm high. It was 0.025 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth and there was no crumb of the conjugated diene polymer falling off in the drop test. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

EXAMPLE 6

The desolvent was performed in accordance with Preparation Example 2 of the crumb, and the composition of the bale crumb was 15 mass% for 0.5 mm crumb, 25 mass% for 3.4 mm crumb, 10 mass% for 4.0 mm crumb and 10 mass for 6.7 mm crumb. It carried out similarly to Example 5 except having set 20 mass% and 8.0 mm crumb to 20 mass%, and 9.5 mm crumb, and obtained the veil of the weight of a rectangular parallelepiped 6 kg. The specific surface area of the bale crumb was 2.90 m 2 / g, and the formed dimensions were 420 mm long side 210 mm short side 210 mm high. It was 0.042 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.72 g, and was 0.012 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

EXAMPLE 7

Using a solution of the dielectric conjugated diene polymer A, the desolvent method was carried out in the same manner as in Example 6 except that the desolvent method was carried out in accordance with Preparation Example 1 of the crumb, thereby obtaining a veil having a weight of 6 kg of a rectangular parallelepiped. The specific surface area of the bale crumb was 2.73 m 2 / g, and the molded dimensions were 420 mm long side 210 mm short side 90 mm high. The specific surface area was measured by cutting out the vicinity of the bale center part, and it was 0.045 m <2> / g. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.72 g, and was 0.012 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

EXAMPLE 8

The solvent was removed in accordance with Preparation Example 1 of the crumb using a solution of the dielectric conjugated diene polymer A to obtain a crumb. The addition amount of TDAE oil was 5 mass parts with respect to 100 mass parts of conjugated diene polymers. Others were carried out in the same manner as in Example 1 to obtain a bale having a weight of 6 kg of a rectangular parallelepiped. The specific surface area of the bale crumb was 1.75 m 2 / g, and the formed dimensions were 420 mm long side 210 mm short side 90 mm high. It was 0.018m <2> / g as the specific surface area was measured by cutting out the vicinity of the bale center part. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.78 g, and was 0.013 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

EXAMPLE 9

The solvent was removed in accordance with Preparation Example 2 of the crumb using a solution of the dielectric conjugated diene polymer A to obtain a crumb. The addition amount of TDAE oil was 5 mass parts with respect to 100 mass parts of conjugated diene polymers. Others were carried out in the same manner as in Example 1 to obtain a bale having a weight of 6 kg of a rectangular parallelepiped. The specific surface area of the bale crumb was 1.82 m 2 / g, and the molded dimensions were 420 mm long side 210 mm short side 90 mm high. It was 0.025 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 0.60 g and was 0.010 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

[Comparative Example 1]

The solution of the dielectric conjugated diene polymer A was desolvented according to Preparation Example 1 of the crumb to obtain a crumb. The addition amount of TDAE oil was 10 mass parts with respect to 100 mass parts of conjugated diene polymers. As a result of sifting the crumb, the 0.5mm crumb is 19% by mass, the 3.4mm crumb is 37% by mass, the 4.0mm crumb is 22% by mass, the 6.7mm crumb is 12% by mass, and the 8.0mm crumb is 6% by mass and 9.5mm The crumb was 4 mass%. The bale shaping | molding was performed as it was, without adjusting the composition of the said crumb, and the bale of the weight of a rectangular parallelepiped 6 kg was obtained. The specific surface area of the bale crumb was 3.46 m 2 / g, and the size of the formed bale was 420 mm long side 210 mm short side 210 mm high. It was 0.056 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 1.32 g, and was 0.022 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

[Comparative Example 2]

A crumb was obtained in the same manner as in Comparative Example 1 except that the amount of TDAE oil added was 10 parts by mass with respect to 100 parts by mass of the conjugated diene polymer. As a result of sieving the crumb, 0.5 mm crumb was 28 mass%, 3.4 mm crumb was 35 mass%, 4.0 mm crumb was 13 mass%, 6.7 mm crumb was 9 mass%, 8.0 mm crumb was 9 mass%, 9.5 mm The crumb was 6 mass%. The bale shaping | molding was performed as it was, without adjusting the composition of the said crumb, and the bale of the weight of a rectangular parallelepiped 6 kg was obtained. The specific surface area of the bale crumb was 4.40 m 2 / g, and the size of the formed bale was 420 mm long side 210 mm short side 210 mm high. It was 0.071 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 1.86 g, and was 0.031 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

(Comparative Example 3)

A crumb was obtained in the same manner as in Comparative Example 2 except that the desolvent method was used as Preparation Example 2 for crumb. As a result of sifting the crumbs, 27 mass% of 0.5 mm crunch, 33 mass% of 3.4 mm crumb, 15 mass% of 4.0 mm crumb, 15 mass% of 6.7 mm crumb, 5 mass% of 8 mm crumb, and 9.5 mm crumb This was 5 mass%. The bale shaping | molding was performed as it was, without adjusting the composition of the said crumb, and the bale of the weight of a rectangular parallelepiped 6 kg was obtained. The specific surface area of the bale crumb was 4.25 m 2 / g, and the size of the formed bale was 420 mm long side 210 mm short side 210 mm high. It was 0.068 m <2> / g when the vicinity of the bale center part was cut out and the specific surface area was measured. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 1.74 g, and was 0.029 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

(Comparative Example 4)

A crumb was obtained in the same manner as in Comparative Example 1 except that a solution of the dielectric conjugated diene polymer B was used instead of the solution of the dielectric conjugated diene polymer A and the amount of TDAE oil was set to 15 parts by mass based on 100 parts by mass of the conjugated diene polymer. . As a result of sifting the crumb, the 0.5mm crumb is 23% by mass, the 3.4mm crumb is 32% by mass, the 4.0mm crumb is 18% by mass, the 6.7mm crumb is 13% by mass, the 8mm crumb is 8% by mass, and the 9.5mm crumb It was 6 mass%. The bale shaping | molding was performed as it was, without adjusting the composition of the said crumb, and the bale of the weight of a rectangular parallelepiped 6 kg was obtained. The specific surface area of the bale crumb was 3.81 m 2 / g, and the size of the molded bale was 420 mm long side 210 mm short side 92 mm high. It was 0.063m <2> / g as the specific surface area was measured by cutting out the vicinity of the bale center part. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 1.26 g, and was 0.021 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

(Comparative Example 5)

A crumb was obtained in the same manner as in Comparative Example 4 except that the desolvent method was followed in Preparation Example 2 of the crumb. As a result of sifting the crumb, 0.5 mm crumb was 22 mass%, 3.4 mm crumb was 35 mass%, 4.0 mm crumb was 16 mass%, 6.7 mm crumb was 12 mass%, 8.0 mm crumb was 9 mass%, 9.5 mm The crumb was 6 mass%. The bale shaping | molding was performed as it was, without adjusting the composition of the said crumb, and the bale of the weight of a rectangular parallelepiped 6 kg was obtained. The specific surface area of the bale crumb was 3.71 m 2 / g, and the size of the molded bale was 420 mm long side 210 mm short side 210 mm high. It was 0.061 m <2> / g as the specific surface area was measured by cutting out the vicinity of the bale center part. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 1.50 g, and was 0.025 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

(Comparative Example 6)

The solution of the dielectric conjugated diene polymer A was desolvented according to Preparation Example 1 of the crumb to obtain a crumb. The addition amount of TDAE oil was 15 mass parts with respect to 100 mass parts of conjugated diene polymers. According to the said crumb particle size control method, the crumb used for bale shaping | mixing was mix | blended and adjusted. As for the compounding composition, 9.5 mm crumb was 100 mass%. The specific surface area of the bale crumb was 0.50 m 2 / g. According to the manufacturing method of the said bale, the 6-weighted bale of the cuboid was obtained. The bale shaping | molding was performed as it was, without adjusting the composition of the said crumb, and the bale of the weight of a rectangular parallelepiped 6 kg was obtained. The size of the molded bale was 420 mm long side 210 mm short side x 87 mm high. The specific surface area was measured by cutting out the vicinity of the bale center part, and it was 0.004 m <2> / g. The bale surface was smooth and there was no crumb of the conjugated diene polymer falling off in the drop test. After one day, the veil angle was measured and the volume was calculated. As a result, the expansion ratio was 6.7%.

(Comparative Example 7)

The solution of the dielectric conjugated diene polymer A was desolvented according to Preparation Example 1 of the crumb to obtain a crumb. The addition amount of TDAE oil was 5 mass parts with respect to 100 mass parts of conjugated diene polymers. The crumb was sieved, and the bale shaping was carried out by adjusting the composition of the crumb particle size distribution to be the same as in Comparative Example 1 to obtain a bale having a weight of 6 kg of a rectangular parallelepiped. The size of the molded bale was 420 mm long side 210 mm short side x 87 mm high. It was 0.065 m <2> / g as the specific surface area was measured by cutting out the vicinity of the bale center part. The bale surface was smooth, and the crumb of the conjugated diene polymer peeled off by the drop test was 2.70 g, and was 0.045 mass% with respect to the bale whole quantity. After one day, each side of the bale was measured to obtain a volume, and the expansion ratio was less than 1%.

The evaluation results of the molding crumb and the bale obtained in the above Examples and Comparative Examples are shown in Tables 1 and 2.

Claims (6)

Crum of conjugated diene polymer having a specific surface area of 0.7 m 2 / g to 3.2 m 2 / g. The crumb of Claim 1 in which a conjugated diene polymer contains 30-90 mass% of components of 1 million or more molecular weight. The crumb according to claim 1 or 2, comprising 1 to 20 parts by mass of process oil with respect to 100 parts by mass of the conjugated diene polymer. A bale of conjugated diene polymer having a specific surface area of from 0.005 m 2 / g to 0.05 m 2 / g. A method for producing a bale, in which a crumb of a conjugated diene polymer having a specific surface area of 0.7 m 2 / g to 3.2 m 2 / g is produced, and the bale is obtained by compression molding. The method for producing a bale according to claim 5, further comprising a step of sifting the crumb of the conjugated diene polymer.