Modifier for polymer, rubber composition, and tire

Abstract

Provided are: a modifier for a polymer, which has a high reaction rate with a polymer and is capable of controlling the amount of cationic groups in the polymer; a modified polymer into which the modifier for a polymer is introduced; and a rubber composition and a tire using the modified polymer. The present invention relates to a modifier for a polymer having an oxidized nitrile group and a cationic group.

Description

Technical Field

[0001] The present invention relates to a polymer modifier, a rubber composition and a tire. Background Art

[0002] As polymers having various properties, rubbers having ionic molecules have been disclosed. For example, it has been proposed to introduce carboxylic acid-containing units into styrene butadiene rubber. However, generally, the reaction rate with the polymer is low, it is difficult to control the amount of carboxylic acid groups in the polymer, and there are problems such as gelation. Summary of the invention [Problems to be solved by the invention]

[0003] The present invention solves the above-mentioned problems and aims to provide a polymer modifier having a high reaction rate with a polymer and capable of controlling the amount of cationic groups in the polymer, a modified polymer having the polymer modifier introduced therein, and a rubber composition and a tire using the modified polymer. [Methods used to solve the problem]

[0004] The present invention relates to a polymer modifier having a nitrile oxide group and a cationic group. [Effects of the Invention]

[0005] According to the present invention, since the polymer modifier has a nitrile oxide group and a cationic group, the reaction rate with the polymer is high and the amount of the cationic group in the polymer can be controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] [ Figure 1 ] is a schematic diagram illustrating an example of a method for synthesizing a nitrile oxide compound having a nitrile oxide group and a cationic group. [ Figure 2 ]yes Figure 1 The total pathway of compounds P1, P2, and P3 1 An example of a H-NMR (proton NMR) spectrum. [ Figure 3 ] is an example of the thermogravimetric analysis result when synthesizing compound P3. [ Figure 4 ] is an example of a synthesis example in which a nitrile oxide compound having a nitrile oxide group and a cationic group reacts with a polymer having a double bond to synthesize a polymer having a cationic group. [ Figure 5 ]yes Figure 4 The total amount of polymer in the 1 An example of a H-NMR (proton NMR) spectrum. [ Figure 6 ] is a schematic diagram illustrating an example of a method for synthesizing a nitrile oxide compound having a nitrile oxide group and an anionic group. [ Figure 7 ] is a graph showing the relationship between strain and stress. DETAILED DESCRIPTION

[0007] <Polymer Modifiers> The present invention is a polymer modifier (nitrile oxide compound) having a nitrile oxide group and a cationic group. The polymer modifier has a high reaction rate with the polymer, and the amount of cationic groups in the polymer can be controlled. In addition, a modified polymer having cationic groups introduced into the polymer, a rubber composition using the modified polymer, and a tire can be provided.

[0008] The applicant proposed in the publication No. WO2022 / 244317 a technology for synthesizing a nitrile oxide compound having a carboxylic acid group and adding styrene butadiene rubber and butadiene rubber to the solution. In this case, although the reaction rate of the nitrile oxide compound having a carboxylic acid group can be controlled to about 60% and the addition rate of the double bond can be controlled to about 0.1-10%, there are problems such as high solution usage, environmental disadvantages, and difficulty in scale-up in solution reactions, and it is also expected to further increase the reaction rate.

[0009] In the present invention, when a nitrile oxide compound having a cationic group such as a pyridyl group is synthesized and the nitrile oxide compound is added to a polymer such as styrene butadiene rubber and butadiene rubber, a high reaction rate can be obtained in the reaction between the nitrile oxide compound and the polymer even in the absence of a solvent. For example, a rubber and a nitrile oxide compound having a pyridyl group are kneaded at a temperature of 70° C. for about 15 minutes to react, and a high reaction rate of about 90% or more is obtained as the reaction rate of the nitrile oxide compound having a pyridyl group. In addition, the reaction rate of a single nitrile oxide compound having a carboxylic acid group when kneaded with a polymer is, for example, less than 30%, but when the nitrile oxide compound having a carboxylic acid group and the nitrile oxide compound having a pyridyl group are kneaded with a polymer together, not only a high reaction rate can be obtained between the nitrile oxide compound having a pyridyl group and the polymer, but also the reaction rate of the nitrile oxide compound having a carboxylic acid group and the polymer can be increased, for example, the reaction rate can be increased to more than 70%. As described above, by using a nitrile oxide compound having a cationic group as a modifier for a polymer, the reaction rate with the polymer is improved, and the addition rate of double bonds (double bond modification rate) can also be controlled. In addition, as a modifier, by using a nitrile oxide compound having an anionic group such as a carboxylic acid group together with a nitrile oxide compound having a cationic group, the reaction rate of the nitrile oxide compound having an anionic group with the polymer can also be improved.

[0010] In the above-mentioned nitrile oxide compound (polymer modifier) ​​having a nitrile oxide group and a cationic group, the nitrile oxide group is a group represented by the following formula: The nitrile oxide compound may be a compound having one nitrile oxide group, or may be a compound having two or more nitrile oxide groups.

[0011]

[0012] In the above-mentioned nitrile oxide compound having a nitrile oxide group and a cationic group, preferably, the cationic group is introduced into the terminal of the nitrile oxide compound. The above-mentioned nitrile oxide compound may be a compound having one cationic group, or may be considered to be a compound having two or more cationic groups. In addition, the cationic group in the above-mentioned nitrile oxide compound may be one kind, or may be two or more kinds.

[0013] As the above-mentioned cationic group, univalent cationic groups such as amino, ammonium, imino and their salts can be listed. As the atom or atomic group constituting the salt, hydroxide ion, halogen ion, carboxylate ion, sulfonate ion, fluoride ion, cyanide ion, silicate ion, borate ion, condensed phosphate ion etc. can be listed. It should be noted that the amino listed as an example of the cationic group is not limited to -NH2, and also includes substituted amino and cyclic amino. As substituted amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkylarylamino etc. can be listed. Examples of the cyclic amino group include pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, pyrrolyl, pyrazolyl, imidazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrrolidonyl, piperidinonyl, 3-morpholinonyl, morpholinedionyl, and substituted groups thereof, and examples of the substituent include halogen groups and monovalent hydrocarbon groups (alkyl, alkenyl, etc.). Among them, from the perspective of obtaining a better effect, a cyclic amino group is preferred, and a pyridinyl and substituted pyridinyl are more preferred.

[0014] Typical examples of the pyridyl group which may be substituted as required include the following 2-pyridyl group, 3-pyridyl group, and 4-pyridyl group: And the following 3-pyridyl substituted with -CH3: wait.

[0015] The nitrile oxide compound is not particularly limited as long as it is a compound having a nitrile oxide group and a cationic group, and examples thereof include compounds represented by the following formula. XC≡N + -O - (In the formula, X represents a monovalent hydrocarbon group containing a cationic group.)

[0016] X is not particularly limited as long as it is a monovalent hydrocarbon group containing a cationic group. In addition, the cationic group contained in X can be, for example, the same group as the above-mentioned cationic group. Regarding the cationic group contained in X, it is preferably formed at the end of X, for example, as shown by X being a group represented by -(CH2)5-A (A: cationic functional group).

[0017] The monovalent hydrocarbon group in X (a monovalent hydrocarbon group containing a cationic group) refers to a monovalent hydrocarbon group constituting the skeleton of X and in which the cationic group is substituted with a hydrogen atom. For example, when X is a group represented by -(CH2)5-C5H4N (pyridyl: cationic group), the monovalent hydrocarbon group in X is -(CH2)5-H.

[0018] As the monovalent hydrocarbon group in X, substituted or unsubstituted monovalent hydrocarbon groups can be listed, which can be any of linear, branched, and cyclic, preferably cyclic. In addition, the monovalent hydrocarbon group in X may contain heteroatoms. As substituents, there are no particular restrictions, and well-known groups such as hydroxyl groups, halogen groups (-Cl, -Br, etc.) can be listed. As heteroatoms, there are no particular restrictions, and oxygen, nitrogen, etc. can be listed. These substituents and heteroatoms may have one or more.

[0019] The number of carbon atoms in the monovalent hydrocarbon group in X is preferably 3 or more, more preferably 6 or more, and is preferably 30 or less, more preferably 20 or less, and further preferably 16 or less.

[0020] Examples of the monovalent hydrocarbon group in X include substituted or unsubstituted linear alkyl groups, branched alkyl groups, cyclic alkyl groups, aryl groups, and aralkyl groups that may contain heteroatoms. In addition, the monovalent hydrocarbon group in X may be a group formed by combining these substituted or unsubstituted linear alkyl groups, branched alkyl groups, cyclic alkyl groups, aryl groups, and aralkyl groups that may contain heteroatoms (a group formed by combining a substituted or unsubstituted linear alkyl group that may contain heteroatoms and a substituted or unsubstituted aryl group that may contain heteroatoms, etc.).

[0021] Among the monovalent hydrocarbon groups in X, examples of substituted or unsubstituted straight-chain alkyl and branched-chain alkyl groups that may contain heteroatoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, 2-ethylhexyl, octyl, nonyl, decyl, and these groups containing heteroatoms. Examples of substituted or unsubstituted cyclic alkyl groups that may contain heteroatoms include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantyl, 1-ethylcyclopentyl, 1-ethylcyclohexyl, and these groups containing heteroatoms. Examples of substituted or unsubstituted aryl groups that may contain heteroatoms include phenyl, tolyl, xylyl, biphenyl, naphthyl, anthracenyl, phenanthryl, and these groups containing heteroatoms. Examples of substituted or unsubstituted aralkyl groups that may contain heteroatoms include benzyl, phenethyl, and these groups containing heteroatoms. Examples of the monovalent hydrocarbon group in X include groups formed by combining these groups (a group formed by combining a substituted or unsubstituted pentyl group which may contain a heteroatom and a substituted or unsubstituted naphthyl group which may contain a heteroatom, etc.).

[0022] The monovalent hydrocarbon group in X is preferably a substituted or unsubstituted straight-chain alkyl group which may contain a heteroatom, a substituted or unsubstituted aryl group which may contain a heteroatom, or a group formed by combining a substituted or unsubstituted straight-chain alkyl group which may contain a heteroatom and a substituted or unsubstituted aryl group which may contain a heteroatom.

[0023] The compound having an oxynitrile group and a cationic group is preferably a compound having a cyclic structure, and more preferably a compound having an aromatic ring. Specific examples of aromatic rings include: a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a fluorene ring, a triphenylene ring, a tetracene ring, a biphenyl ring, a bisphenol ring, a terphenyl ring (three benzene rings can be connected in any connection mode), etc. Among them, compounds having a benzene ring and a naphthalene ring are preferred, and compounds having a naphthalene ring are more preferred.

[0024] Preferred examples of the nitrile oxide compound having a nitrile oxide group and a cationic group include compounds represented by the following formula (compounds having a naphthalene ring).

[0025] (In the formula, A represents a monovalent cationic group. Y represents a substituted or unsubstituted divalent hydrocarbon group which may contain a heteroatom.)

[0026] Examples of A (monovalent cationic group) include the monovalent cationic groups described above.

[0027] Y (a substituted or unsubstituted divalent hydrocarbon group which may contain a heteroatom) may be any of a linear, branched, or cyclic shape. In addition, as heteroatoms and substituents in Y, for example, the above-mentioned heteroatoms and substituents may be listed. Y may have one of these substituents and heteroatoms, or may have two or more of these substituents and heteroatoms.

[0028] The number of carbon atoms of the divalent hydrocarbon group in Y is preferably 1 or more, and is preferably 20 or less, more preferably 10 or less, and further preferably 6 or less.

[0029] Examples of Y (a substituted or unsubstituted divalent hydrocarbon group which may contain a hetero atom) include a substituted or unsubstituted alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkylalkylene group, an arylene group, an aralkylene group, and an oxyalkylene group which may contain a hetero atom.

[0030] As substituted or unsubstituted alkylene groups which may contain heteroatoms, methylene, ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, octylene, nonylene, decylene, 1,2-propylene, and groups containing heteroatoms thereof, etc. can be cited. As substituted or unsubstituted alkenylene groups which may contain heteroatoms, vinylene, 1-propylene, 2-propylene, and groups containing heteroatoms thereof, etc. can be cited. As substituted or unsubstituted cycloalkylene groups which may contain heteroatoms, cyclohexylene, and groups containing heteroatoms thereof, etc. can be cited. As substituted or unsubstituted cycloalkylalkylene groups which may contain heteroatoms, cyclohexylmethylene, and groups containing heteroatoms thereof, etc. can be cited. As substituted or unsubstituted arylene groups which may contain heteroatoms, phenylene, tolylene, xylylene, and groups containing heteroatoms thereof, etc. can be cited. Examples of the substituted or unsubstituted aralkylene group which may contain a hetero atom include a benzylidene group and such groups containing a hetero atom. Examples of the substituted or unsubstituted oxyalkylene group which may contain a hetero atom include an oxyethylene group, an oxypropylene group, an oxybutylene group, an oxytetramethylene group and such groups containing a hetero atom.

[0031] The compound having a naphthalene ring represented by the above formula is one preferred example. + -O - The substitution position of the group represented by -YA is not particularly limited, and may be any one of the 1st to 8th positions. Among them, it is preferred that the 1st and 2nd positions are substituted by -C≡N + -O - , -YA replaced.

[0032] Next, the synthesis method of the nitrile oxide compound having the above-mentioned nitrile oxide group and the cationic group is described. Hereinafter, an example of the synthesis method of the nitrile oxide compound having the above-mentioned nitrile oxide group and the cationic group is described, but the nitrile oxide compound is not limited to the nitrile oxide compound obtained by such a synthesis method, and includes the nitrile oxide compound obtained by any synthesis method that can be synthesized.

[0033] First, a compound having a hydroxyl group and an aldehyde group is used as a starting material, and the compound having a hydroxyl group and an aldehyde group is reacted with a compound capable of introducing a cationic group. If necessary, a group derived from the compound capable of introducing a cationic group in the obtained material is substituted with the cationic group.

[0034] Next, the aldehyde group in the obtained compound is converted into a group represented by -CH=N-OH, and the group represented by -CH=N-OH is further converted into a group represented by -C≡N + -O - The group represented by can synthesize a nitrile oxide compound having a nitrile oxide group and a cationic group.

[0035] In addition, the reaction process can be carried out in an organic solvent, in water, or in the absence of a solvent. The organic solvent is not particularly limited, and is preferably a solvent in which the compound to be reacted and the reaction compound are easily soluble. As an organic solvent, it is not particularly limited, and examples thereof include: toluene, mesitylene, chloroform (CHCl3), alcohol, THF (tetrahydrofuran), etc. In addition, a catalyst can be used as needed. As a catalyst, it is not particularly limited, and examples thereof include: DMF (N, N-dimethylformamide), DMSO (dimethyl sulfoxide), triethylamine (TEA), etc. The amount of solvent and the amount of catalyst can be appropriately set according to the compound. The reaction temperature and time can also be appropriately set according to the compound. Regarding the reaction temperature, for example, 10 to 100°C can be cited, preferably 20 to 80°C, and regarding the reaction time, for example, 1 to 200 hours can be cited, preferably 3 to 100 hours.

[0036] The synthesis examples of specific compounds are described. For example, Figure 1 The synthetic route shown can synthesize a nitrile oxide compound having a nitrile oxide group and a cationic group represented by compound P3.

[0037] First, compound S (a compound having a hydroxyl group and an aldehyde group) is used as a starting material, and the compound S is reacted with a compound capable of introducing a cationic group (C5H4N-CH2-Cl (wherein C5H4N represents a 2-pyridyl group)) to obtain compound P1.

[0038] The aldehyde group in the obtained compound P1 is converted into a group represented by -CH=N-OH to synthesize compound P2. The group represented by -CH=N-OH in the obtained compound P2 is converted into a group represented by -C≡N + -O - The group represented by the formula (a) was used to synthesize compound P3 (a nitrile oxide compound having a nitrile oxide group and a cationic group).

[0039] Figure 2 yes Figure 1 The synthesis of compounds P1, P2, and P3 1 An example of a H-NMR (proton NMR) spectrum. Figure 3 This is an example of the result of thermogravimetric analysis (TGA) during the synthesis of compound P3 (nitrile oxide compound (CNO-Py) having a nitrile oxide group and a cationic group). Figure 2 The spectra of Figure 3 The results of TGA are shown in Figure 1 Compounds P1, P2, and P3 were synthesized using the synthetic route.

[0040] <Modified polymer> The modified polymer obtained by reacting a nitrile oxide compound having a nitrile oxide group and a cationic group with a polymer is a modified polymer obtained by reacting the nitrile oxide compound having a nitrile oxide group and a cationic group with a polymer (a polymer having an unsaturated bond, etc.). By using the modified polymer, mechanical properties, wet grip performance, etc. are improved.

[0041] Although the mechanism by which the above-mentioned effects are obtained is not clear, it is presumed as follows. Since the above-mentioned nitrile oxide compound with nitrile oxide group and cationic group can react with various unsaturated polymers, it is easy to add the nitrile oxide compound to unsaturated polymers such as diene rubber, and the polymer with ionic bonding point (position of ionic bond formation) can be easily synthesized, and in addition, it is also easy to adjust the content of ionic bonding point in the polymer. The ionic polymer has ion clusters in the polymer, and the mechanical properties are improved. In addition, for example, in the case where the diene rubber introduced with the nitrile oxide compound is applied to a tire rubber composition, when the rubber composition is in contact with a wet road surface, the ionic bonding point dissociates, crosslinking is relaxed, and the elastic modulus is reduced. Therefore, when driving on a wet road surface, the contact area with the road surface increases, friction is improved, and loss is improved, and it can be inferred that the wet grip performance is improved.

[0042] The method of reacting the nitrile oxide compound having the nitrile oxide group and the cationic group with the polymer can be any method that can react. For example, as required, the nitrile oxide compound and the polymer having the unsaturated bond are dissolved or energized, thereby causing a cycloaddition reaction between the nitrile oxide group and the carbon-carbon double bond in the main chain of the polymer, and a reaction to generate a five-membered ring can be performed.

[0043] Examples of the polymer include polymers having a carbon-carbon double bond. As the polymer having carbon-carbon double bonds, for example, rubber components such as diene rubbers can be cited. As diene rubbers, isoprene rubbers, butadiene rubber (BR), styrene butadiene rubber (SBR), styrene isoprene butadiene rubber (SIBR), ethylene propylene diene rubber (EPDM), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), etc. can be cited. In addition, butyl rubbers, fluororubbers, etc. can also be cited. Among them, from the perspective of tire performance such as wet grip performance, SBR, BR, and isoprene rubbers are preferred, and SBR and BR are more preferred.

[0044] The above-mentioned diene rubber may be an unmodified diene rubber or a modified diene rubber. The modified diene rubber may be any diene rubber having a functional group that interacts with a filler such as silica, and examples thereof include a terminal-modified diene rubber obtained by modifying at least one terminal of a diene rubber with a compound (modifier) ​​having the functional group (terminal-modified diene rubber having the functional group at the terminal), a main chain-modified diene rubber having the functional group on the main chain, a main chain-terminal-modified diene rubber having the functional group on the main chain and the terminal (for example, a main chain-terminal-modified diene rubber having the functional group on the main chain and at least one terminal modified with the modifier), a terminal-modified diene rubber modified (coupled) with a polyfunctional compound having two or more epoxy groups in the molecule, and having a hydroxyl group or an epoxy group introduced therein, and the like.

[0045] As the above functional group, for example, amino, amide, silyl, alkoxysilyl, isocyanate, imino, imidazole, urea, ether, carbonyl, oxycarbonyl, mercapto, sulfide, disulfide, sulfonyl, sulfinyl, thiocarbonyl, ammonium, imido, hydrazo, azo, diazo, carboxyl, nitrile, pyridyl, alkoxy, hydroxyl, oxy, epoxy, etc. can be cited. It should be noted that these functional groups may have substituents. Among them, amino (preferably, an amino group in which the hydrogen atom possessed by the amino group is replaced by an alkyl group having 1 to 6 carbon atoms), alkoxy (preferably, an alkoxy group having 1 to 6 carbon atoms), and alkoxysilyl (preferably, an alkoxysilyl group having 1 to 6 carbon atoms) are preferred.

[0046] The SBR is not particularly limited, and for example, emulsion polymerized styrene butadiene rubber (E-SBR), solution polymerized styrene butadiene rubber (S-SBR), etc. can be used. These can be used alone or in combination of two or more.

[0047] The styrene content of SBR is preferably 5% by mass or more, more preferably 20% by mass or more, and further preferably 24% by mass or more. The styrene content is preferably 60% by mass or less, more preferably 40% by mass or less, and further preferably 35% by mass or less. Within the above range, there is a tendency to obtain better effects. It should be noted that, in this specification, the styrene content can be 1 The results were determined by H-NMR measurement.

[0048] The styrene amount of SBR refers to the styrene amount of the SBR when there is one type of SBR, and refers to the average styrene amount when there are multiple types of SBR. The average styrene content of SBR can be calculated by {∑(content of each SBR×styrene content of each SBR)} / total content of all SBRs. For example, in 100% by mass of the rubber component, when SBR with a styrene content of 40% by mass is 85% by mass and SBR with a styrene content of 25% by mass is 5% by mass, the average styrene content of SBR is 39.2% by mass (=(85×40+5×25) / (85+5)).

[0049] The vinyl bonding amount of SBR is preferably 3% by mass or more, more preferably 10% by mass or more, and further preferably 17% by mass or more. The vinyl bonding amount is preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 30% by mass or less. Within the above range, there is a tendency to obtain better effects. In addition, in this specification, the vinyl bond amount (1,2-bonded butadiene unit amount) can be measured by infrared absorption spectrum analysis method.

[0050] The vinyl amount (1,2-bonded butadiene unit amount) of SBR is the ratio of vinyl bonds (unit: mass%) when the total mass of the butadiene part in SBR is 100, vinyl amount [mass%] + cis amount [mass%] + trans amount [mass%] = 100 [mass%]. When there is one type of SBR, it refers to the vinyl amount of the SBR, and when there are multiple types of SBR, it refers to the average vinyl amount. The average vinyl content of SBR can be calculated by ∑{content of each SBR×(100[mass %]-styrene content of each SBR[mass %])×vinyl content of each SBR[mass %]} / ∑{content of each SBR×(100[mass %]-styrene content of each SBR[mass %])}. For example, in 100 parts by mass of the rubber component, 75 parts by mass of SBR having a styrene content of 40% and a vinyl content of 30% is used, and 25 parts by mass of SBR having a styrene content of 25% is used. When the amount of SBR having a vinyl content of 20% by mass is 15 parts by mass and the remaining 10 parts by mass are other than SBR, the average vinyl content of SBR is 28% by mass (={75×(100[mass%]-40[mass%])×30[mass%]+15×(100[mass%]-25[mass%])×20[mass%])} / {75×(100[mass%]-40[mass%])+15×(100[mass%]-25[mass%])}.

[0051] SBR can use any one of unmodified SBR and modified SBR. As modified SBR, modified SBR introduced with the same functional group as modified rubber can be enumerated. In addition, as SBR, hydrogenated styrene-butadiene copolymer (hydrogenated SBR) can also be used.

[0052] As SBR, for example, SBR manufactured and sold by Sumitomo Chemical Co., Ltd., JSR Corporation, Asahi Kasei Corporation, Nippon Zeon Corporation, etc. can be used. In addition, SBR synthesized by a known method can also be used.

[0053] BR is not particularly limited, for example, high cis BR with a high cis content, BR containing syndiotactic polybutadiene crystals, BR synthesized using a rare earth catalyst (rare earth BR), etc. can be used. They can be used alone, or two or more can be used in combination. Among them, BR preferably includes a high cis BR with a cis content of 90% by mass or more. The cis content is more preferably 95% by mass or more. It should be noted that the cis content can be measured by infrared absorption spectrometry.

[0054] The cis-amount of BR refers to the cis-amount of the BR when there is one type of BR, and refers to the average cis-amount when there are multiple types of BR. The average cis content of BR can be calculated by {∑(content of each BR×cis content of each BR)} / total content of all BRs. For example, in the rubber component of 100 mass%, when BR with a cis content of 90 mass% is 20 mass% and BR with a cis content of 40 mass% is 10 mass%, the average cis content of BR is 73.3 mass% (=(20×90+10×40) / (20+10)).

[0055] In addition, BR may be either unmodified BR or modified BR. As the modified BR, there may be mentioned a modified BR into which the same functional group as the modified rubber is introduced. In addition, a hydrogenated butadiene polymer (hydrogenated BR) may be used as BR.

[0056] As BR, for example, products of Ube Industries, Ltd., JSR Corporation, Asahi Kasei Corporation, Nippon Zeon Corporation, etc. can be used.

[0057] As isoprene-based rubber, natural rubber (NR), isoprene rubber (IR), modified NR, modified NR, modified IR, etc. can be listed. As NR, for example, NR commonly used in the rubber industry such as SIR20, RSS#3, TSR20, etc. can be used. As IR, there is no particular limitation, for example, IR commonly used in the rubber industry such as IR2200 can be used. As modified NR, deproteinized natural rubber (DPNR), high purity natural rubber (UPNR), etc. can be listed; as modified NR, epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), grafted natural rubber, etc. can be listed; as modified IR, epoxidized isoprene rubber, hydrogenated isoprene rubber, grafted isoprene rubber, etc. can be listed. They can be used alone, or two or more types can be used in combination.

[0058] The reaction process of the above-mentioned nitrile oxide compound and the polymer such as the above-mentioned diene rubber is not particularly limited, and can be carried out in an organic solvent, in water, or can be carried out without a solvent. As the organic solvent, it is not particularly limited, and it is preferred that the above-mentioned nitrile oxide compound and the polymer are both easily soluble in an organic solvent. As a specific example of the organic solvent, for example, the above-mentioned organic solvent can be cited. The reaction temperature and time can be appropriately set according to the above-mentioned nitrile oxide compound and the above-mentioned polymer.

[0059] In particular, even in the absence of a solvent, the polymer and the nitrile oxide compound can be kneaded to react with each other, and during the kneading, a modified polymer obtained by the reaction of the nitrile oxide compound having a nitrile oxide group and a cationic group with the polymer can be obtained. In the above kneading process, the reaction temperature (kneading temperature) and the reaction temperature (kneading time) can be appropriately set to the temperature and time for the reaction. The reaction temperature (kneading temperature) is preferably 10 to 100° C., more preferably 50 to 80° C., and the reaction time (kneading time) is preferably 1 minute to 200 hours, more preferably 3 minutes to 100 hours, and further preferably 5 minutes to 1 hour.

[0060] The synthesis examples of specific compounds are described. For example, Figure 4 The synthetic route shown can synthesize a reaction product (modified polymer) of the above-mentioned nitrile oxide compound having a nitrile oxide group and a cationic group and a polymer having a double bond.

[0061] For example, by kneading the nitrile oxide compound having a nitrile oxide group and a cationic group (the above-mentioned compound P3) with BR and SBR (diene rubber) at 70° C. for 15 minutes, the target reaction product (modified polymer having a cationic group) can be obtained. In addition, a high reaction rate of the above-mentioned compound P3 can be obtained.

[0062] Figure 5 yes Figure 4 The synthetic route of the polymer 1 An example of a H-NMR (proton NMR) spectrum. (A) is BR 1 An example of H-NMR spectrum, (B) is SBR 1 An example of H-NMR spectrum, (C) is BR having a pyridyl group (cationic group) 1 An example of H-NMR spectrum, (D) is SBR having a pyridyl group (cationic group) 1 An example of H-NMR spectrum. Figure 5 (C) and (D) represent the reaction of a nitrile oxide compound having a nitrile oxide group and a cationic group (the above-mentioned compound P3) with BR and SBR to synthesize a polymer having a cationic group.

[0063] <Rubber Composition> The rubber composition contains, as a rubber component, the modified polymer (hereinafter also referred to as "modified polymer (A)") obtained by reacting the nitrile oxide compound having a nitrile oxide group and a cationic group with the polymer. By using the modified polymer, mechanical properties, wet grip performance, etc. are improved.

[0064] Conventionally, when a rubber composition using ionic bonds is prepared, the types of ion-modified rubbers are limited. For example, when SBR is used, there are restrictions on the SBR skeleton. However, when the above-mentioned nitrile oxide compound is used, a cationic group can be added without depending on the structure of the skeleton, so that it becomes easy to adjust the mechanical properties, further improve the wet grip performance, etc.

[0065] The rubber composition is a composition containing the modified polymer (A), but may also be a composition in which a modified polymer (A) synthesized in advance by the above-mentioned production method is mixed with other components, or may be a composition containing the following modified polymer (A): when the polymer such as the above-mentioned diene rubber, the above-mentioned nitrile oxide compound having a nitrile oxide group and a cationic group and other components as required are kneaded under the above-mentioned kneading conditions to prepare a composition, the polymer reacts with the nitrile oxide compound during kneading to produce a modified polymer (A).

[0066] In order to obtain better effects, the rubber composition preferably contains, as the rubber component, in addition to the modified polymer (A), a modified polymer (B) obtained by reacting a nitrile oxide compound having a nitrile oxide group and anionic groups with a polymer.

[0067] As the above-mentioned anionic group, halogen groups, acidic functional groups, etc. can be listed. As the halogen group, fluorine groups, chlorine groups, bromine groups and iodine groups can be listed. As the acidic functional group, hydroxyl groups, carboxylic acid groups, sulfonic acid groups, sulfuric acid groups, phosphonic acid groups, phosphoric acid groups, phosphinic acid groups, maleic acid groups, anhydride groups (maleic anhydride groups, etc.), fumaric acid groups, itaconic acid groups, acrylic acid groups, methacrylic acid groups, mercapto groups, etc. can be listed. Among them, carboxylic acid groups (carboxyl groups) are preferred.

[0068] Examples of the nitrile oxide compound having a nitrile oxide group and an anionic group include compounds obtained by replacing the cationic group of the nitrile oxide compound having a nitrile oxide group and a cationic group with an anionic group.

[0069] Regarding the synthesis of the above-mentioned nitrile oxide compound having a nitrile oxide group and an anionic group, for example, first, a compound having a hydroxyl group and an aldehyde group is used as a starting material, and the compound having a hydroxyl group and an aldehyde group is reacted with a compound that can introduce an anionic group. If necessary, the group from the compound that can introduce an anionic group in the obtained substance is substituted with the anionic group. Then, the aldehyde group in the obtained compound is converted into a group represented by -CH=N-OH, and the group represented by -CH=N-OH is further converted into a group represented by -C≡N + -O -The group represented by can synthesize a nitrile oxide compound having a nitrile oxide group and an anionic group. Specifically, the nitrile oxide compound having a nitrile oxide group and an anionic group can be synthesized by the method described in WO2022 / 244317.

[0070] In the above-mentioned modified polymer (B), the method for making the above-mentioned nitrile oxide compound with nitrile oxide group and anionic group react with polymer can use any method that can react.For example, as needed, the nitrile oxide compound and the polymer with unsaturated bond are dissolved or energy is given, thus cycloaddition reaction occurs between the carbon-carbon double bond in the main chain of the nitrile oxide group and the polymer, and the reaction of generating a five-membered ring can be carried out. Specifically, by the method described in WO2022 / 244317, the above-mentioned nitrile oxide compound with nitrile oxide group and anionic group is reacted with polymer, and the above-mentioned modified polymer (B) can be synthesized accordingly. In addition, by the above-mentioned method of mixing the polymer and the nitrile oxide compound under solvent-free conditions, the above-mentioned modified polymer (B) can also be synthesized.

[0071] The rubber composition contains the modified polymer (A) and, if necessary, the modified polymer (B) and other rubber components. Herein, the rubber component is generally a polymer having a weight average molecular weight (Mw) of 10,000 or more, and is a rubber component that cannot be extracted by acetone. The rubber component is in a solid state at room temperature (25° C.) and is a component that contributes to crosslinking.

[0072] In the rubber composition, examples of the rubber component include, in addition to the modified polymers (A) and (B), the polymers such as the diene rubber and the like.

[0073] The weight average molecular weight of the rubber component is preferably 50,000 or more, more preferably 150,000 or more, further preferably 200,000 or more, particularly preferably 270,000 or more, and preferably 2,000,000 or less, more preferably 1,500,000 or less, further preferably 1,000,000 or less. When it is within the above range, there is a tendency to obtain better effects.

[0074] It should be noted that in this specification, the weight average molecular weight (Mw) can be obtained by conversion to standard polystyrene based on the measured value obtained by gel permeation chromatography (GPC) (GPC-8000 series manufactured by Tosoh Corporation, detector: differential refractometer, chromatographic column: TSKGEL SUPERMULTIPORE HZ-M manufactured by Tosoh Corporation). In addition, in the case of a polymer having a modified group, the modified group interacts with the silica gel of the chromatographic column and the correct Mw cannot be obtained, so the Mw is measured before the modification treatment is performed.

[0075] In the rubber composition, in 100% by mass of the rubber component, the content of the modified polymer (A) (modified polymer obtained by reacting a nitrile oxide compound having a nitrile oxide group and a cationic group with a polymer) is preferably 5% by mass or more, more preferably 10% by mass or more. It is further preferably 15% by mass or more, and can be 100% by mass, or can be 90% by mass or less, 85% by mass or less, or 80% by mass or less. When within the above range, there is a tendency to obtain a better effect. It should be noted that, regarding the content of the above-mentioned modified polymer (A), in the case of a composition in which a modified polymer (A) synthesized by reacting a nitrile oxide compound having a nitrile oxide group and a cationic group with a polymer in advance by the above-mentioned production method, etc., and mixed with other components, it refers to the content of the modified polymer (A). Furthermore, when a polymer, a nitrile oxide compound having a nitrile oxide group and a cationic group, and other components as required are kneaded under the above-mentioned kneading conditions, etc., and the polymer reacts with the nitrile oxide compound during kneading to form the modified polymer (A), it refers to the total amount of the polymer and the nitrile oxide compound.

[0076] In the rubber composition, in 100% by mass of the rubber component, the content of the modified polymer (B) (modified polymer obtained by reacting a nitrile oxide compound having a nitrile oxide group and anionic groups with a polymer) is preferably 5% by mass or more, more preferably 10% by mass or more. It is further preferably 15% by mass or more, and can be 100% by mass, or can be 90% by mass or less, 85% by mass or less, or 80% by mass or less. When within the above range, there is a tendency to obtain a better effect. It should be noted that, regarding the content of the above-mentioned modified polymer (B), in the case of a composition in which a modified polymer (B) synthesized by reacting a nitrile oxide compound having a nitrile oxide group and anionic groups with a polymer in advance by the above-mentioned production method is mixed with other components, it refers to the content of the modified polymer (B). Furthermore, when a polymer, a nitrile oxide compound having a nitrile oxide group and anionic groups, and other components as required are kneaded under the above-mentioned kneading conditions, etc., and the polymer reacts with the nitrile oxide compound during kneading to form the modified polymer (B), it refers to the total amount of the polymer and the nitrile oxide compound.

[0077] When the rubber composition contains a modified SBR (A) obtained by reacting the nitrile oxide compound having a nitrile oxide group and a cationic group with SBR, the content of the modified SBR (A) is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more in 100% by mass of the rubber component, and is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. Within the above range, there is a tendency to obtain a better effect.

[0078] When the rubber composition contains a modified BR (A) obtained by reacting the nitrile oxide compound having a nitrile oxide group and a cationic group with BR, the content of the modified BR (A) in 100% by mass of the rubber component is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more, and is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. Within the above range, there is a tendency to obtain better effects.

[0079] When the rubber composition contains a modified isoprene rubber (A) obtained by reacting the nitrile oxide compound having a nitrile oxide group and a cationic group with an isoprene rubber, the content of the modified isoprene rubber (A) in 100% by mass of the rubber component is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more, and is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. Within the above range, there is a tendency to obtain better effects.

[0080] When the rubber composition contains a modified SBR (B) obtained by reacting the nitrile oxide compound having a nitrile oxide group and anionic groups with SBR, the content of the modified SBR (B) is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more in 100% by mass of the rubber component, and is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. Within the above range, there is a tendency to obtain a better effect.

[0081] When the rubber composition contains a modified BR (B) obtained by reacting the nitrile oxide compound having a nitrile oxide group and an anionic group with BR, the content of the modified BR (B) in 100% by mass of the rubber component is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more, and is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. Within the above range, there is a tendency to obtain better effects.

[0082] When the rubber composition contains a modified isoprene rubber (B) obtained by reacting the nitrile oxide compound having a nitrile oxide group and an anionic group with an isoprene rubber, the content of the modified isoprene rubber (B) in 100% by mass of the rubber component is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more, and is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. Within the above range, there is a tendency to obtain better effects.

[0083] It should be noted that, when one or more polymers, one or more nitrile oxide compounds having nitrile oxide groups and ionic groups (cationic groups or anionic groups), and other components as required are kneaded under the above-mentioned kneading conditions, and during kneading, each polymer reacts with each nitrile oxide compound to generate two or more modified polymers, the content of each modified polymer is: based on the content ratio of the two or more polymers and the content ratio of the two or more nitrile oxide compounds having nitrile oxide groups and ionic groups (cationic groups or anionic groups), the content of each modified polymer is proportionally distributed. For example, when two polymers (60 parts by mass of BR and 40 parts by mass of isoprene rubber) and 10 parts by mass of a nitrile oxide compound having a nitrile oxide group and a cationic group (polymer modifier) ​​are kneaded to generate modified BR and modified isoprene rubber during kneading, and a rubber composition containing these is produced, the ratio of the nitrile oxide compound having a nitrile oxide group and a cationic group that modifies BR is 6 parts by mass (=10×60 / (60+40)), and the content of the modified BR is 66 parts by mass (=60+6), the ratio of the nitrile oxide compound having a nitrile oxide group and a cationic group that modifies the isoprene rubber is 4 parts by mass (=10×40 / (60+40)), and the content of the modified isoprene rubber is 44 parts by mass (=40+4).

[0084] Preferably, the rubber composition contains a filler. The filler is not particularly limited, and materials known in the rubber field can be used, for example, inorganic fillers such as carbon black, silica, calcium carbonate, talc, alumina, clay, aluminum hydroxide, aluminum oxide, and mica, biochar, and poorly dispersible fillers, etc. Among them, carbon black and silica are preferred from the perspective of obtaining better effects.

[0085] In the rubber composition, the content of the filler (the total amount of fillers such as carbon black and silica) is preferably 2 parts by mass or more, more preferably 10 parts by mass or more, and further preferably 15 parts by mass or more, and preferably 150 parts by mass or less, more preferably 120 parts by mass or less, and further preferably 100 parts by mass or less, relative to 100 parts by mass of the rubber component. When it is within the above range, there is a tendency to obtain better effects. It should be noted that, in the present specification, the nitrile oxide compound having a nitrile oxide group and a cationic group is not included in the filler.

[0086] As carbon black, there is no particular limitation, and N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, N762, etc. can be cited. As commercial products, products of Asahi Carbon Co., Ltd., Cabot Japan Co., Ltd., Tokai Carbon Co., Ltd., Mitsubishi Chemical Co., Ltd., Lion Co., Ltd., Shin Nichia Carbon Co., Ltd., Columbia Carbon (Columbia Carbon) Co., Ltd., etc. can be used. They can be used alone, or two or more can be used in combination. In addition, in addition to the carbon black made from mineral oils and the like in the past, carbon black made from biomass materials such as lignin can also be used. In addition, regenerated carbon black (recycled carbon black) can be used.

[0087] The nitrogen adsorption specific surface area (N2SA) of carbon black is preferably 5 m 2 / g or more, more preferably 50m 2 / g or more, more preferably 90m 2 / g or more. In addition, the above N2SA is preferably 200m 2 / g or less, more preferably 130m 2 / g or less, more preferably 120m 2 When it is within the above range, there is a tendency for the effect to be better obtained. In addition, the nitrogen adsorption specific surface area of ​​carbon black is calculated|required according to JIS K6217-2:2001.

[0088] In the rubber composition, the content of carbon black is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and further preferably 5 parts by mass or more, relative to 100 parts by mass of the rubber component, and is preferably 100 parts by mass or less, more preferably 50 parts by mass or less, and further preferably 30 parts by mass or less. When within the above range, there is a tendency to obtain better effects.

[0089] In the above-mentioned rubber composition, as usable silica, dry process silica (anhydrous silica), wet process silica (hydrous silica) etc. can be listed. Among them, from the reason of many silanol groups, wet process silica is preferred. As commercially available products, products of Degussa, Rhodia, Tosoh Silica Corporation, Solvay Japan Co., Ltd., Tokuyama Corporation etc. can be used. They can be used alone, or two or more can be used in combination.

[0090] As the silicon dioxide, silicon dioxide derived from plants can also be used appropriately. As the silica from plants, silica from plants containing silica components can be cited. As plants containing silica components, rice, corn, sugar cane, horsetail, wheat, barley, rye, rye, millet, foxtail millet, barnyard grass, awn, and sedge can be cited. In addition, saccharification residues of the above-mentioned plants containing silica components can also be used. Among them, rice husks and rice straws with high silica content are preferred, and rice husks are more preferred. In addition, plants containing silica components can be treated to ash by burning, or carbonization can be performed.

[0091] In the rubber composition, the content of silica is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and further preferably 15 parts by mass or more, relative to 100 parts by mass of the rubber component, and is preferably 150 parts by mass or less, more preferably 100 parts by mass or less, and further preferably 80 parts by mass or less. Within the above range, there is a tendency to obtain better effects.

[0092] The nitrogen adsorption specific surface area (N2SA) of silicon dioxide is preferably 50 m 2 / g or more, more preferably 100m 2 / g or more, more preferably 150m 2 / g or more. In addition, the upper limit of N2SA of silica is not particularly limited, but is preferably 350 m 2 / g or less, more preferably 300m 2 / g or less, more preferably 250m 2 When it is within the above range, there is a tendency for the effect to be better obtained. It should be noted that the N2SA of silica is a value measured by the BET method in accordance with ASTM D3037-93.

[0093] Examples of the poorly dispersible filler include microfibrillated plant fibers, short-fiber cellulose, gel-like compounds, etc. Among them, microfibrillated plant fibers are preferred.

[0094] As the above-mentioned microfibrillated plant fibers, cellulose microfibrils are preferred from the perspective of obtaining good reinforcement. As cellulose microfibrils, there are no particular restrictions as long as they are cellulose microfibrils from natural materials. For example, cellulose microfibrils from resource biomass such as fruits, grains, and root vegetables, wood, bamboo, hemp, jute, kenaf, and pulp or paper, cloth, crop residues, food waste, sewage sludge and other waste biomass obtained from these as raw materials, unused biomass such as rice straw, wheat straw, and thinning materials, and cellulose produced by sea squirts, acetic acid bacteria, etc. can be cited. These microfibrillated plant fibers can be used alone, or two or more can be used in combination.

[0095] It should be noted that, in this specification, cellulose microfibrils typically refer to cellulose fibers having an average fiber diameter of 10 μm or less, and more typically refer to cellulose fibers having a microstructure formed by an assembly of cellulose molecules and having an average fiber diameter of 500 nm or less. Typical cellulose microfibrils are formed, for example, as an assembly of cellulose fibers having the above-mentioned average fiber diameter.

[0096] When the rubber composition contains a poorly dispersible filler, the content of the poorly dispersible filler is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and further preferably 5 parts by mass or more, relative to 100 parts by mass of the rubber component. The upper limit of the content is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, further preferably 20 parts by mass or less, and particularly preferably 10 parts by mass or less. Within the above range, there is a tendency to obtain better effects.

[0097] When the rubber composition contains silica, it is preferred that the rubber composition further contains a silane coupling agent. The silane coupling agent is not particularly limited, and any silane coupling agent known in the rubber field can be used. Examples thereof include bis(3-triethoxysilylpropyl)tetrasulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(4-triethoxysilylbutyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, bis(2-triethoxysilylbutyl)tetrasulfide, bis(trimethoxysilylethyl) trisulfide, bis(4-trimethoxysilylbutyl) trisulfide, bis(3-triethoxysilylpropyl) disulfide, bis(2-triethoxysilylethyl) disulfide, bis(4-triethoxysilylbutyl) disulfide, bis(3-trimethoxysilylpropyl) disulfide, bis(2-trimethoxysilylethyl) disulfide, bis(4-trimethoxysilylbutyl) disulfide Sulfide-based products such as 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyl tetrasulfide, and 3-triethoxysilylpropyl methacrylate monosulfide; mercapto-based products such as 3-mercaptopropyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, and NXT and NXT-Z manufactured by Momentive; ethylene The present invention relates to a vinyl-based silane such as triethoxysilane and vinyl trimethoxysilane; an amino-based silane such as 3-aminopropyl triethoxysilane and 3-aminopropyl trimethoxysilane; a glycidoxy-based silane such as γ-glycidoxypropyl triethoxysilane and γ-glycidoxypropyl trimethoxysilane; a nitro-based silane such as 3-nitropropyl trimethoxysilane and 3-nitropropyl triethoxysilane; a chlorine-based silane such as 3-chloropropyl trimethoxysilane and 3-chloropropyl triethoxysilane. As commercially available products, products of Degussa, Momentive, Shin-Etsu Silicone Co., Ltd., Tokyo Chemical Industry Co., Ltd., AZmax Co., Ltd., Toray Dow Corning Co., Ltd., etc. can be used. These can be used alone or in combination of two or more.

[0098] In the rubber composition, the content of the silane coupling agent is preferably 0.1 parts by mass or more, more preferably 3 parts by mass or more, further preferably 5 parts by mass or more, and more preferably 7 parts by mass or more, relative to 100 parts by mass of silica. The upper limit of the content is preferably 50 parts by mass or less, more preferably 20 parts by mass or less, further preferably 15 parts by mass or less, and particularly preferably 10 parts by mass or less. Within the above range, there is a tendency to obtain a better effect.

[0099] The rubber composition may contain a plasticizer. In the present specification, the plasticizer is a material that imparts plasticity to the rubber component, and may be liquid or solid at room temperature (25° C.) These may be used alone or in combination of two or more. It should be noted that, in the present specification, the nitrile oxide compound having a nitrile oxide group and a cationic group is not included in the plasticizer.

[0100] Examples of the plasticizer include oils, liquid polymers, resins, etc. These may be used alone or in combination of two or more.

[0101] As the above-mentioned oil, there is no particular limitation, and the previously known oils such as paraffinic process oil, aromatic process oil, naphthenic process oil, low PCA (polycyclic aromatic) process oils such as TDAE and MES, oils from plants, and mixtures thereof can be used. They can be used alone, or two or more can be used in combination. It should be noted that, from the perspective of life cycle analysis, lubricating oils, waste cooking oils, etc. used in rubber mixing mixers, automobile engines, etc. can be appropriately used.

[0102] Examples of the plant-derived oil (also referred to as vegetable oil) include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, peanut oil, rosin, pine oil, pine tar, tall oil, corn oil, rice oil, safflower oil, sesame oil, olive oil, sunflower oil, palm kernel oil, camellia oil, jojoba oil, macadamia oil, and tung oil.

[0103] As the above oil, for example, products of Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo Co., Ltd., Nippon Energy Co., Ltd., Olisoy Co., Ltd., H&R Co., Ltd., Toyokuni Oil Refining Co., Ltd., Showa Shell Sekiyu Co., Ltd., Fuji Kosan Co., Ltd., Nissin Oillio Group Co., Ltd., etc. can be used.

[0104] As the above-mentioned liquid polymer, for example, liquid diene polymer (liquid rubber) at 25° C., liquid farnesene polymer, etc. can be cited. As the liquid rubber, liquid styrene butadiene copolymer (liquid SBR), liquid butadiene polymer (liquid BR), liquid isoprene polymer (liquid IR), liquid styrene isoprene copolymer (liquid SIR), liquid styrene butadiene styrene block copolymer (liquid SBS block polymer), liquid styrene isoprene styrene block copolymer (liquid SIS block polymer), etc. can be cited. The ends and main chains of these can be modified with polar groups. In addition, these hydrogenated products can also be used.

[0105] The weight average molecular weight (Mw) of the liquid diene polymer measured by gel permeation chromatography (GPC) in terms of polystyrene is preferably 1.0×10 3 ~5.0×10 4 , more preferably 3.0×10 3 ~1.5×10 4In addition, the lower limit or upper limit of Mw of the liquid diene polymer may be 4,500 or 8,500. In addition, in this specification, Mw of a liquid diene polymer is a polystyrene conversion value measured by gel permeation chromatography (GPC).

[0106] As the liquid diene polymer, for example, products produced by Sartomer Co., Ltd., Kuraray Co., Ltd., etc. can be used.

[0107] As the above-mentioned resin, as a tire compound, a commonly used resin can be used, which can be liquid or solid at room temperature (25°C). For example, it can be listed: aromatic vinyl polymers, coumarone-indene resins, coumarone resins, indene resins, phenolic resins, rosin resins, petroleum resins, terpene resins, acrylic resins, etc. In addition, the resin can be a hydrogenated resin (hydrogenated resin). They can be used alone or in combination of two or more. In addition, the resin itself can be a copolymer from a variety of monomer components. Among them, aromatic vinyl polymers, petroleum resins, terpene resins, and their hydrogenated resins are preferred.

[0108] When a resin that is solid at room temperature is used, the softening point of the resin is preferably 50° C. or higher, more preferably 55° C. or higher, further preferably 60° C. or higher, and particularly preferably 85° C. or higher. In addition, it is preferably 160° C. or lower, more preferably 150° C. or lower, further preferably 140° C. or lower, and particularly preferably 100° C. or lower. When it is within the above range, there is a tendency that a better effect is obtained. When the resin is liquid at room temperature, the softening point is preferably 20° C. or lower, preferably 10° C. or lower, and preferably 0° C. or lower. In the case of hydrogenated resins, the softening point is preferably the same as above. The softening point of the resin is the softening point specified in JIS K6220-1:2001 measured using a ring and ball softening point measuring device, and is the temperature at which the ball falls.

[0109] The aromatic vinyl polymer is a polymer containing an aromatic vinyl monomer as a constituent unit. For example, resins obtained by polymerizing α-methylstyrene and / or styrene can be cited, and specifically, homopolymers of styrene (styrene resins), homopolymers of α-methylstyrene (α-methylstyrene resins), copolymers of α-methylstyrene and styrene, copolymers of styrene and other monomers, etc. can be cited.

[0110] The coumarone-indene resin is a resin containing coumarone and indene as main monomer components constituting the resin skeleton (main chain). Examples of monomer components contained in the skeleton other than coumarone and indene include styrene, α-methylstyrene, methylindene, vinyltoluene, and the like.

[0111] The coumarone resin is a resin containing coumarone as a main monomer component constituting the resin skeleton (main chain).

[0112] The indene resin is a resin containing indene as a main monomer component constituting the resin skeleton (main chain).

[0113] As the phenolic resin, for example, a known phenolic resin such as a polymer obtained by reacting phenol with an aldehyde such as formaldehyde, acetaldehyde, or furfural using an acid or alkali catalyst can be used. Among them, a phenolic resin obtained by reacting with an acid catalyst (such as a novolac phenolic resin) is preferred.

[0114] Examples of the rosin resin include natural rosin, polymerized rosin, modified rosin, ester compounds thereof, and rosin-based resins represented by hydrogenated products thereof.

[0115] Examples of the petroleum resin include C5 resins, C9 resins, C5 / C9 resins, dicyclopentadiene (DCPD) resins, C9 / DCPD resins, and hydrogenated products thereof, etc. Among them, DCPD resins, hydrogenated DCPD resins, C9 / DCPD resins, and C9 / hydrogenated DCPD resins are preferred.

[0116] The above-mentioned terpene resin is a polymer containing terpene as a constituent unit. For example, polyterpene resins obtained by polymerizing terpene compounds, aromatic modified terpene resins obtained by polymerizing terpene compounds and aromatic compounds, etc. can be listed. As aromatic modified terpene resins, terpene phenol resins using terpene compounds and phenolic compounds as raw materials, terpene styrene resins using terpene compounds and styrene compounds as raw materials, and terpene phenol styrene resins using terpene compounds, phenolic compounds and styrene compounds as raw materials can also be used. It should be noted that as terpene compounds, α-pinene, β-pinene, etc. can be listed, as phenolic compounds, phenol, bisphenol A, etc. can be listed, and as aromatic compounds, styrene compounds (styrene, α-methylstyrene, etc.) can be listed. Among them, aromatic modified terpene resins are preferred.

[0117] The acrylic resin is a polymer containing an acrylic monomer as a constituent unit. For example, styrene acrylic resins such as styrene acrylic resins obtained by copolymerizing an aromatic vinyl monomer component and an acrylic monomer component having a carboxyl group can be cited. Among them, solvent-free styrene acrylic resins containing a carboxyl group can be preferably used.

[0118] As the above-mentioned resin, for example, products of Maruzen Petrochemical Co., Ltd., Sumitomo Bakelite Co., Ltd., Yasuhara Chemical Co., Ltd., Tosoh Corporation, Rutgers Chemicals, BASF, Arizona Chemical Company, ExxonMobil Corporation, KRATON, Nippon Paint Chemical Co., Ltd., Nippon Shokubai Co., Ltd., ENEOS Co., Ltd., Arakawa Chemical Industries, Ltd., and Taoka Chemical Industries, Ltd. can be used.

[0119] As the plasticizer, from the viewpoint of sustainability, it is preferred to use a plant-derived plasticizer such as the plant-derived oil or farnesene polymer.

[0120] Farnesene polymers are polymers obtained by polymerizing farnesene, and have structural units based on farnesene. Farnesene includes isomers such as α-farnesene ((3E,7E)-3,7,11-trimethyl-1,3,6,10-dodetetraene) and β-farnesene (7,11-dimethyl-3-methylene-1,6,10-dodecatriene), and (E)-β-farnesene having the following structure is preferred.

[0121] The farnesene polymer may be a homopolymer of farnesene (farnesene homopolymer), or a copolymer of farnesene and a vinyl monomer (farnesene-vinyl monomer copolymer). They may be used alone, or two or more may be used in combination. Among them, a copolymer of farnesene and a vinyl monomer is preferred.

[0122] As the vinyl monomer, styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 4-tert-butylstyrene, 5-tert-butyl-2-methylstyrene, vinylethylbenzene, divinylbenzene, trivinylbenzene, divinylnaphthalene, tert-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl)dimethylaminoethylether, N,N-dimethylaminoethylstyrene, N,N-dimethylaminomethylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-tert-butylstyrene, 3-tert-butylstyrene, 4-tert-butylstyrene, vinylxylene, vinylnaphthalene, vinyltoluene, vinylpyridine, diphenylethylene, aromatic vinyl compounds such as diphenylethylene containing tertiary amino groups, butadiene, conjugated diene compounds such as isoprene, etc. can be listed. They can be used alone or in combination of two or more. Among them, butadiene is preferred. That is, as the farnesene-vinyl monomer copolymer, a copolymer of farnesene and butadiene (farnesene-butadiene copolymer) is preferred.

[0123] In the farnesene-vinyl monomer copolymer, the copolymerization ratio of farnesene to vinyl monomer (farnesene / vinyl monomer) based on mass is preferably 40 / 60 to 90 / 10.

[0124] Farnesene polymers having a weight average molecular weight (Mw) of 3000 or more and 300,000 or less can be used appropriately. The Mw of the farnesene polymer is preferably 8000 or more, more preferably 10000 or more, and preferably 100,000 or less, more preferably 60,000 or less, and further preferably 50,000 or less. Within the above range, there is a tendency to obtain better effects.

[0125] The farnesene polymer may be any of a farnesene polymer in a liquid state at room temperature (25° C.) or a farnesene polymer in a solid state. Among them, a liquid farnesene polymer in a liquid state at room temperature (25° C.) is preferred.

[0126] When the rubber composition contains a plasticizer, the content of the plasticizer (the total amount of the plasticizer) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and further preferably 15 parts by mass or more relative to 100 parts by mass of the rubber component. The upper limit is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and further preferably 30 parts by mass or less. Within the above range, there is a tendency to obtain a better effect. It should be noted that the content of the plasticizer also includes the amount of oil and resin contained in the oil-extended rubber and the resin-filled rubber.

[0127] In the rubber composition, the content of the solid plasticizer in a solid state at room temperature (25° C.) is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and further preferably 7 parts by mass or more, relative to 100 parts by mass of the rubber component. The upper limit is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and further preferably 12 parts by mass or less. Within the above range, there is a tendency to obtain better effects. In addition, the content of the above-mentioned resin in a solid state at room temperature (25° C.) is also preferably in the same range.

[0128] In the rubber composition, the content of the liquid plasticizer in a liquid state at room temperature (25° C.) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and further preferably 15 parts by mass or more, relative to 100 parts by mass of the rubber component. The upper limit is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and further preferably 30 parts by mass or less. Within the above range, there is a tendency to obtain better effects. It should be noted that the content of the liquid plasticizer also includes the amount of oil contained in the oil-extended rubber and the amount of liquid resin in the resin-extended rubber extended with a liquid resin. The content of the oil that is liquid at room temperature (25° C.) is also preferably in the same range.

[0129] From the viewpoint of crack resistance, ozone resistance and the like, the rubber composition preferably contains an antioxidant.

[0130] The antioxidant is not particularly limited, and examples thereof include naphthylamine antioxidants such as phenyl-α-naphthylamine; diphenylamine antioxidants such as octylated diphenylamine and 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine; p-phenylenediamine antioxidants such as N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and N,N'-di-2-naphthyl-p-phenylenediamine; quinoline antioxidants such as polymers of 2,2,4-trimethyl-1,2-dihydroquinoline; monophenol antioxidants such as 2,6-di-tert-butyl-4-methylphenol and styrenated phenol; di-, tri- and polyphenol antioxidants such as tetrakis-[methylene-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate]methane; and the like. Among them, p-phenylenediamine antioxidants and quinoline antioxidants are preferred, and polymers of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and 2,2,4-trimethyl-1,2-dihydroquinoline are more preferred. As commercially available products, for example, products of Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinko Chemical Co., Ltd., Flexsys Co., Ltd., etc. can be used.

[0131] In the rubber composition, the content of the antioxidant is preferably 0.2 parts by mass or more, more preferably 2.0 parts by mass or more, and further preferably 3.4 parts by mass or more, relative to 100 parts by mass of the rubber component. The content is preferably 10.0 parts by mass or less, and more preferably 6.0 parts by mass or less.

[0132] Preferably, the rubber composition contains stearic acid. In the rubber composition, the content of stearic acid is preferably 0.5 parts by mass or more, more preferably 1.5 parts by mass or more, and is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, based on 100 parts by mass of the rubber component.

[0133] As stearic acid, conventionally known stearic acid can be used. For example, products of NOF Corporation, Kao Corporation, Fujifilm Wako Pure Chemical Industries, Ltd., Chiba Fatty Acid Co., Ltd., etc. can be used.

[0134] Preferably, the rubber composition contains zinc oxide. In the rubber composition, the content of zinc oxide is preferably 0.5 parts by mass or more, more preferably 1.5 parts by mass or more, and is preferably 6.0 parts by mass or less, more preferably 4.0 parts by mass or less, based on 100 parts by mass of the rubber component.

[0135] As zinc oxide, conventionally known zinc oxide can be used, for example, products of Mitsui Mining & Smelting Co., Ltd., Toho Zinc Industry Co., Ltd., Shiramizu Techno Co., Ltd., Shodo Chemical Industry Co., Ltd., Sakai Chemical Industry Co., Ltd., etc. can be used.

[0136] The above-mentioned rubber composition may contain wax. In the rubber composition, the wax content is preferably 0.5 parts by mass or more, more preferably 1.6 parts by mass or more, and is preferably 8.0 parts by mass or less, more preferably 5.0 parts by mass or less, based on 100 parts by mass of the rubber component.

[0137] The wax is not particularly limited, and petroleum waxes, natural waxes, etc. may be mentioned. In addition, synthetic waxes obtained by refining or chemically treating various waxes may also be used. These waxes may be used alone or in combination of two or more.

[0138] Examples of petroleum waxes include paraffin wax and microcrystalline wax. Examples of natural waxes include plant waxes such as candelilla wax, carnauba wax, wood wax, rice wax, and jojoba wax; animal waxes such as beeswax, lanolin, and spermaceti; mineral waxes such as ozokerite, ceresin, and petrolatum; and purified products thereof. Examples of commercially available products include products of Ouchi Shinko Chemical Industry Co., Ltd., Nippon Seiro Co., Ltd., and Seiko Chemical Co., Ltd.

[0139] In the rubber composition, sulfur is preferably blended from the viewpoint of forming appropriate crosslinking chains on polymer chains and imparting good performance.

[0140] In the rubber composition, the sulfur content is preferably 1.0 parts by mass or more, more preferably 1.3 parts by mass or more, and even more preferably 1.6 parts by mass or more, relative to 100 parts by mass of the rubber component. The sulfur content is preferably 7.0 parts by mass or less, more preferably 5.0 parts by mass or less, and even more preferably 4.0 parts by mass or less.

[0141] As sulfur, powdered sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, highly dispersible sulfur, soluble sulfur, etc. commonly used in the rubber industry can be cited. As commercially available products, products of Tsurumi Chemical Industry Co., Ltd., Karuizawa Sulfur Co., Ltd., Shikoku Chemical Industry Co., Ltd., Flexsys Co., Ltd., Nippon Senryu Industry Co., Ltd., Hosoi Chemical Industry Co., Ltd., etc. can be used. These can be used alone or in combination of two or more.

[0142] Preferably, the rubber composition contains a vulcanization accelerator. In the rubber composition, the content of the vulcanization accelerator is not particularly limited, and can be freely determined according to the desired vulcanization speed and crosslinking density. It is preferably 0.1 parts by mass or more, more preferably 1.0 parts by mass or more, and further preferably 1.7 parts by mass or more relative to 100 parts by mass of the rubber component. The upper limit is preferably 8.0 parts by mass or less, more preferably 5.0 parts by mass or less, and further preferably 4.0 parts by mass or less.

[0143] The type of vulcanization accelerator is not particularly limited, and commonly used vulcanization accelerators can be used. Examples of the vulcanization accelerator include benzothiazole-based vulcanization accelerators such as 2-mercaptobenzothiazole, di-2-benzothiazolyl disulfide, and N-cyclohexyl-2-benzothiazole sulfenamide; thiuram-based vulcanization accelerators such as tetramethylthiuram disulfide (TMTD), tetrabenzylthiuram disulfide (TBzTD), and tetrakis(2-ethylhexyl)thiuram disulfide (TOT-N); sulfenamide-based vulcanization accelerators such as N-cyclohexyl-2-benzothiazole sulfenamide, N-tert-butyl-2-benzothiazolyl sulfenamide, N-oxyethylene-2-benzothiazole sulfenamide, and N,N'-diisopropyl-2-benzothiazole sulfenamide; and guanidine-based vulcanization accelerators such as diphenylguanidine, di-o-tolylguanidine, and o-tolylbiguanide. These may be used alone or in combination of two or more. Among them, sulfenamide-based, guanidine-based, and benzothiazole-based vulcanization accelerators are preferred.

[0144] The rubber composition may contain, in addition to the above components, compounding agents commonly used in the tire industry, such as a mold release agent.

[0145] The rubber composition can be produced, for example, by kneading the above-mentioned components using a rubber kneading device such as an open roll or a Banbury mixer, and then vulcanizing the mixture.

[0146] As the mixing conditions, in the basic mixing step of mixing additives other than the crosslinking agent (vulcanizing agent) and the vulcanization accelerator, the mixing temperature is preferably 100°C or more, more preferably 120°C or more, and preferably 180°C or less, and more preferably 170°C or less. In the final mixing step of mixing the vulcanizing agent and the vulcanization accelerator, the mixing temperature is preferably 80°C or more, and preferably 120°C or less, and more preferably 110°C or less. In addition, the composition of the mixed vulcanizing agent and the vulcanization accelerator can usually be subjected to vulcanization treatment such as press vulcanization. As the vulcanization temperature, it is preferably 140°C or more, more preferably 150°C or more, and preferably 190°C or less, and more preferably 185°C or less.

[0147] The rubber composition can be used for tires, shoe soles, floor materials, vibration-proof materials, anti-vibration materials, butyl frame materials, belts, hoses, packings, suppositories, other rubber industrial products, etc. In particular, it is preferably used as a rubber composition for tires from the perspective of excellent tire performance such as wet grip performance.

[0148] There are no particular limitations on the tire components to which the rubber composition is applied, and examples thereof include: a tread surface, a sidewall, a tread base, a bead apex, a lap apex, an inner liner, a base tread, a buffer layer topping, a cord layer topping, and any other tire components. Among them, the tread surface can be preferably used from the perspective of excellent wet grip performance.

[0149] <Tires> The rubber composition can be preferably used for tires. As tires, pneumatic tires, non-pneumatic tires, etc. can be listed, among which pneumatic tires are preferred. In particular, it can be preferably used as summer tires (summer tires), winter tires (studless tires, snow tires, studded tires, etc.), all-season tires, etc. The tire can be used for passenger car tires, large passenger car tires, large SUV tires, trucks, buses and other heavy-duty tires, light truck tires, two-wheeled motor vehicle tires, racing tires (high-performance tires), etc. Among them, it can be preferably used for passenger car tires and light truck tires.

[0150] The tire can be manufactured by conventional methods using the above-mentioned rubber composition. For example, the tire can be manufactured by the following method: the rubber composition compounded with various materials is extruded into the shape of a tire component in an unvulcanized stage, and is molded together with other tire components on a tire molding machine by conventional methods to form an unvulcanized tire, and then the unvulcanized tire is heated and pressurized in a vulcanizer to manufacture the tire. [Example]

[0151] Hereinafter, examples (embodiments) considered to be preferable in practice will be described, but the scope of the present invention is not limited to the embodiments.

[0152] <Synthesis of Nitrile Oxide Compound Having Nitrile Oxide Group and Cationic Group (CNO-Py)> pass Figure 1 Compound P3 (a nitrile oxide compound having a nitrile oxide group and a cationic group) was synthesized by the synthetic route shown.

[0153] (Compound S → Compound P1) Add a stirring bar to a three-necked flask, add 2-hydroxy-1-naphthaldehyde (compound S) and DMF (N,N-dimethylformamide), and stir to dissolve. Add K2CO3 to the above flask and stir for 1 hour. Add 2-(chloromethyl)pyridine hydrochloride to the above mixture and stir to dissolve. Heat the solution in an oil bath and react at 100°C. After 3 hours, cool the solution to room temperature, dilute with ethyl acetate, put into a separatory funnel, and separate with water and NaCl aqueous solution. Collect the organic layer, dry with MgSO4, and remove the solvent with an evaporator. The obtained crude product is recrystallized from ethanol to obtain compound P1.

[0154] (Compound P1 → Compound P2) Add a stirring bar to a beaker, add compound P1 and ethanol, and stir to dissolve. Add an aqueous solution of CH3COONa·3H2O and NH2OH·HCl to the beaker of P1 and react at room temperature for 4 hours. Then, add a large amount of water to the above reaction solution to precipitate compound P2. Collect the precipitate and dry it to obtain compound P2.

[0155] (Compound P2 → Compound P3) Compound P2 was dispersed in 2-propanol, and NaClO aqueous solution was added to the compound P2 solution in a dropping funnel at 0-5°C to react. After the addition was completed, the reaction was allowed to proceed for 1 hour, and a large amount of water was added to the solution to precipitate compound P3. The precipitate was collected and dried to obtain compound P3 (nitrile oxide compound having a nitrile oxide group and a cationic group, CNO-Py).

[0156] Based on the composite 1 H-NMR spectrum ( Figure 2 )、TGA( Figure 3 ) It can be seen that compound P3 (a nitrile oxide compound having a nitrile oxide group and a cationic group) was synthesized.

[0157] <Synthesis of Nitrile Oxide Compound Having Nitrile Oxide Group and Anionic Group (CNO-COOH)> pass Figure 6 Compound C4 (a nitrile oxide compound having a nitrile oxide group and an anionic group) was synthesized by the synthetic route shown.

[0158] (Compound S → Compound C1) First, a stirrer, 2-hydroxy-1-naphthaldehyde (compound S), K2CO3, DMF (N,N-dimethylformamide), and ethyl 6-bromohexanoate were added to a three-necked flask and stirred to dissolve. Then, the mixture was heated in an oil bath and reacted at 100°C for 3 hours. The mixture was cooled to room temperature and separated using ethyl acetate and water. The ethyl acetate layer was dried with MgSO4 and evaporated. The residue was recrystallized with hexane to obtain compound C1.

[0159] (Compound C1 → Compound C2) Compound C1 and LiOH were dissolved in a mixed solvent of THF:iPrOH:H2O=(4:2:1), and reacted overnight at room temperature. After the reaction was completed, hydrochloric acid was used for neutralization and evaporation was performed. The residue was diluted with water and added to a separatory funnel together with ethyl acetate for separation. The ethyl acetate layer was dried with MgSO4, evaporated to dryness, and then vacuum dried to obtain compound C2.

[0160] (Compound C2 → Compound C3) Add a stirring bar, compound C2 and ethanol to a 500 ml beaker and stir to dissolve. Add an aqueous solution of CH3COONa·3H2O and NH2OH·HCl to the compound C2 solution and react at room temperature for 4 hours to obtain a precipitate. Filter the mixture, collect the precipitate, and vacuum dry to obtain compound C3.

[0161] (Compound C3 → Compound C4) Add a stirrer, compound C3, and 2-propanol to a three-necked flask, place in an ice bath, and stir to disperse. Add NaClO aqueous solution to the flask using a dropping funnel at 0-5°C for reaction. After the reaction is completed, adjust the pH to about 5 with HCl, and add a large amount of water to precipitate compound C4. The precipitate is recrystallized with ethanol / water to obtain the target compound C4 (nitrile oxide compound having a nitrile oxide group and anionic group, CNO-COOH).

[0162] <Synthesis of Modified Polymer (A)> According to Table 1, the above-mentioned compound P3 (an oxynitrile compound having an oxynitrile group and a cationic group, CNO-Py) is added to SSBR or BR, kneaded at 70°C for 15 minutes, and reacted during kneading to obtain a modified polymer (A) (modified polymers (Py_SBR_K1, Py_SBR_K2, Py_SBR_K3, Py_BR_K1, Py_BR_K2, Py_BR_K3) obtained by reacting an oxynitrile compound having an oxynitrile group and a cationic group with a polymer).

[0163] <Synthesis of Modified Polymer (B)> According to Table 2, the above-mentioned compound C4 (an oxidized nitrile compound having an oxidized nitrile group and an anionic group, CNO-COOH) is added to SSBR or BR, kneaded at 70°C for 15 minutes, and reacted during kneading to obtain a modified polymer (B) (modified polymers (COOH_SBR_K1, COOH_SBR_K2, COOH_SBR_K3, COOH_BR_K1, COOH_BR_K2, COOH_BR_K3) obtained by reacting an oxidized nitrile compound having an oxidized nitrile group and anionic group with a polymer).

[0164] <Synthesis of Modified Polymer (C)> According to Table 3, the above-mentioned compound P3 is added to SSBR or BR, kneaded at 70°C for 15 minutes, and then the above-mentioned compound C4 is added to the mixture, kneaded at 70°C for 15 minutes, and reacted during kneading to obtain modified polymers (C) (Py_COOH_SBR_K1, Py_COOH_SBR_K2, Py_COOH_SBR_K3, Py_COOH_BR_K1, Py_COOH_BR_K2, Py_COOH_BR_K3) modified with anions and cations.

[0165] In addition, the SBR and BR in Tables 1, 2, and 3 used the following materials. SBR (SSBR): HPR840 (S-SBR) manufactured by JSR Corporation BR: BR150B manufactured by Ube Industries, Ltd. (cis content: 96 mass%)

[0166] The double bond modification rates and nitrile oxide compound reaction rates in Tables 1, 2, and 3 are defined as follows and measured by the following methods. (Double bond modification rate (%)) = [the amount of carbon-carbon double bonds reacted with the nitrile oxide compound / (the amount of remaining carbon-carbon double bonds + the amount of carbon-carbon double bonds reacted with the nitrile oxide compound] × 100 (Nitrile oxide compound reaction rate (%)) = (amount of nitrile oxide compound reacting with double bond / (amount of nitrile oxide compound added) × 100

[0167] (1) Double bond modification rate By IR measurement, 1 H-NMR determination and 13 C-NMR measurement was used to calculate the ratio of the nitrile oxide compound added to the carbon-carbon double bond in the polymer.

[0168] (2) Reaction rate of nitrile oxide compounds By IR measurement, 1 H-NMR determination and 13It was obtained by C-NMR measurement.

[0169] [Table 1] Mixing results of CNO-Py and SBR / BR

[0170] [Table 2] Mixing results of CNO-COOH and SBR / BR

[0171] [Table 3]

[0172] (Elongation test) The elongation test was carried out by using a modified SBR prepared by kneading addition (SBR and the above-mentioned compounds P3 and C4 were controlled at a rotation speed of 50 rpm and a temperature of 70°C or less, and kneaded for 15 minutes each. During the kneading, SBR reacted with P3 and C4 to produce modified SBR) and pressed at 70°C for 10 minutes to obtain a 1 mm thick sheet. Specifically, an elongation test was performed at 23° C. and an elongation rate of 100 mm / min using a biaxial elongation tester (manufactured by AIS Giken Co., Ltd.). Figure 7 Represents the relationship between strain and stress.

[0173] Tables 1 and 2 show that the double bond modification rate of the modified polymer (B) (a modified polymer obtained by reacting a nitrile oxide compound having a nitrile oxide group and an anionic group with a polymer) is 0.4 to 4.8%, and the nitrile oxide compound reaction rate is 20.0 to 27.8%. In contrast, the double bond modification rate of the modified polymer (A) (a modified polymer obtained by reacting a nitrile oxide compound having a nitrile oxide group and a cationic group with a polymer) is 2.2 to 15.5%, and the nitrile oxide compound reaction rate is 83.3 to 95.0%. By using a nitrile oxide compound having a nitrile oxide group and a cationic group, the double bond modification rate can be controlled while the nitrile oxide compound reaction rate is increased.

[0174] Table 3 shows that the double bond modification rate of the nitrile oxide compound having a nitrile oxide group and an anionic group is improved by using the nitrile oxide compound having a nitrile oxide group and a cationic group together with the nitrile oxide compound having a nitrile oxide group and an anionic group.

[0175] <Preparation of Rubber Composition> The following is a summary of the various chemicals used. SBR: HPR840 (S-SBR) manufactured by JSR Corporation BR: BR150B manufactured by Ube Industries, Ltd. (cis content: 96 mass%) Carbon black: Showblack N220 (N2SA: 111m 2 / g, DBP absorption: 115ml / 100g) Silicon dioxide: Ultrasil VN3 (N2SA: 175m 2 / g) Silane coupling agent: Si266 manufactured by Evonik Degussa CNO-Py: The above-mentioned nitrile oxide compound having a nitrile oxide group and a cationic group CNO-COOH: The above-mentioned nitrile oxide compound having a nitrile oxide group and an anionic group Sulfur: Powdered sulfur manufactured by Tsurumi Chemical Co., Ltd. Vulcanization accelerator 1: Nocceler NS (N-tert-butyl-2-benzothiazole sulfenamide) manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Vulcanization accelerator 2: Nocceler D (1,3-diphenylguanidine) manufactured by Ouchi Shinko Chemical Industry Co., Ltd.

[0176] (Manufacturing of rubber composition) According to the formulations shown in Tables 4 and 5, chemicals other than the CNO material (CNO-COOH, CNO-Py), sulfur and the vulcanization accelerator were kneaded at 130° C. for 5 minutes using a 1.7 L Banbury mixer manufactured by Kobe Steel, Ltd. to obtain a kneaded product. To the kneaded product, CNO materials (CNO-COOH, CNO-Py) were added, and kneaded at 70° C. for 15 minutes to obtain a kneaded product. Sulfur and a vulcanization accelerator were added to the kneaded product, and kneaded at 70° C. for 4 minutes to obtain an unvulcanized rubber composition. The unvulcanized rubber composition was press-vulcanized at 170° C. for 12 minutes to obtain a vulcanized rubber composition.

[0177] The physical properties of the vulcanized rubber composition were measured and evaluated as follows. The results are shown in Tables 4 to 5. The reference comparative examples are shown below. Table 4: Comparative Example 1-1 Table 5: Comparative Example 2-1

[0178] <Crack Growth Resistance> According to JIS K6260: 2017, a flexure crack growth test was performed, and the vulcanized rubber composition (sheet) was flexed repeatedly at 70% elongation for 1 million times, and then the length of the crack generated was measured. The reciprocal of the measured value of the benchmark comparative example was taken as 100 and the index was expressed. The larger the index, the smaller the crack and the better the crack growth resistance.

[0179] <Tensile test> A dumbbell No. 7 test piece was prepared and a tensile test was performed using a tensile tester (RTG-1210) manufactured by A&D Co., Ltd. at a test temperature of 23°C and a tensile test speed of 200 mm / min. The greater the breaking strength TB and the breaking elongation EB, the better the breaking characteristics (durability). TB: It represents the strength at break TB (MPa) per unit cross-sectional area of ​​the thinnest part (the dumbbell neck part located in the center) of the test piece. EB: The test piece was placed on a testing machine with a distance between chucks of 20 mm, and a tensile test was performed. The distance between chucks at break was measured, and the elongation at break EB (%) was calculated from the value given by the following formula. Distance between fixtures at break (mm) / initial distance between fixtures (20mm)×100

[0180] <Wet Grip Performance> Tan δ of the vulcanized rubber composition was measured using a viscoelasticity spectrometer VES (manufactured by Iwamoto Seisakusho) at a frequency of 10 Hz, a strain of 0.1%, and a temperature of 0° C. The tan δ of the reference comparative example was set to 100 and the index was expressed. A larger index value indicates better wet grip performance.

[0181] [Table 4]

[0182] [Table 5]

[0183] According to Table 4, when SBR, BR, nitrile oxide compounds (cationic group, CNO-Py), nitrile oxide compounds (anionic group, CNO-COOH) and other materials are mixed, CNO-Py modified SBR, CNO-Py modified BR, CNO-COOH modified SBR, and CNO-COOH modified BR are generated during mixing.

[0184] The present invention (1) is a polymer modifier having a nitrile oxide group and a cationic group.

[0185] The present invention (2) is the polymer modifier according to the present invention (1), wherein the cationic group is an amino group.

[0186] The present invention (3) is the polymer modifier according to the present invention (2), wherein the amino group is a pyridyl group.

[0187] The present invention (4) is a modified polymer obtained by reacting a polymer having a nitrile oxide group and a cationic group in any combination of any one of the present inventions (1) to (3) with a polymer.

[0188] The present invention (5) is the modified polymer according to the present invention (4), wherein the polymer is a diene rubber.

[0189] The present invention (6) is a rubber composition comprising the modified polymer described in the present invention (4) or (5).

[0190] The present invention (7) is the rubber composition according to the present invention (6), wherein the rubber composition further contains a modified polymer (B) obtained by reacting a polymer modifier (B) having a nitrile oxide group and an anionic group with a polymer.

[0191] The present invention (8) is a tire using the rubber composition described in the present invention (6) or (7).

Claims

1. A polymer modifier, characterized in that: The polymer modifier has a nitrile oxide group and a cationic group.

2. The polymer modifier according to claim 1, wherein The cationic group is an amino group.

3. The polymer modifier according to claim 2, wherein The amino group includes -NH2, a substituted amino group and a cyclic amino group.

4. The polymer modifier according to claim 2, wherein The amino group is a pyridyl group.

5. A modified polymer, characterized in that The modified polymer is obtained by reacting the polymer modifier having a nitrile oxide group and a cationic group according to any one of claims 1 to 4 with a polymer.

6. The modified polymer according to claim 5, wherein The polymer is a diene rubber.

7. A rubber composition, characterized in that: The rubber composition contains the modified polymer according to claim 5 or 6.

8. The rubber composition according to claim 7, wherein The rubber composition further contains a modified polymer B obtained by reacting a polymer modifier B having a nitrile oxide group and an anionic group with a polymer.

9. A tire, characterized in that: The tire uses the rubber composition according to claim 7 or 8.

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