WO2013094719A1 - Anti-aging agent for rubbers - Google Patents

Abstract

The present invention provides an anti-aging agent for rubbers, which comprises: mesoporous silica in which the pore volume of each mesopore is more than 0.81 cm³/g; and an anti-aging substance for rubbers which is supported on the mesoporous silica.

Description

Anti-aging agent for rubber

The present invention relates to an anti-aging agent for rubber.

Patent Document 1 describes a vulcanized rubber composition containing N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine, which is an anti-aging material for rubber, and silica. .

JP 2011-132471 A

The conventional vulcanized rubber composition contains the rubber anti-aging substance itself as it is, and its anti-aging effect may not always be sufficiently satisfactory in terms of sustainability.

The present invention includes the following inventions.
1. Mesoporous silica having a pore volume of mesopores exceeding 0.81 cm ³ / g;
A rubber anti-aging agent containing the rubber anti-aging substance supported on the mesoporous silica (hereinafter sometimes referred to as “anti-aging agent for rubber of the present invention”).
2. A rubber anti-aging agent obtained by supporting a rubber anti-aging material on mesoporous silica having a mesopore pore volume exceeding 0.81 cm ³ / g.
3. 1 pore volume of the mesopores is equal to or less than 0.84 cm ³ / g or more 5.0 cm ³ / g. Or 2. Antiaging agent for rubber of description.
4). In solid state NMR measurement, the peak chemical shift based on ¹³ C contained in the rubber anti-aging substance supported on the mesoporous silica is based on ¹³ C contained in the rubber anti-aging substance not supported on the mesoporous silica. 1. It is different from the chemical shift of the peak. ~ 3. The anti-aging agent for rubber | gum as described in any one of these.
5. The mesoporous silica has a mesopore diameter of 6 nm or more and 50 nm or less. ~ 4. The anti-aging agent for rubber | gum as described in any one of these.
6). 1. The rubber anti-aging substance is a compound represented by the formula (I): ~ 4. The anti-aging agent for rubber | gum as described in any one of these.

(In the formula (I), R ¹ represents a hydrogen atom or an alkyl group having 1 to 13 carbon atoms.)
7). The mesoporous silica is contained in an amount of 0.1 to 100 parts by weight with respect to 10 parts by weight of the rubber anti-aging material. ~ 6. The anti-aging agent for rubber | gum as described in any one of these.

In the vulcanized rubber composition containing the antiaging agent for rubber of the present invention, the durability of the antiaging effect of the antiaging substance for rubber contained therein is improved.

It is a figure which shows the result of the solid-state NMR measurement of the antiaging substance for rubber | gum. 2 is a diagram showing the results of solid state NMR measurement of the rubber anti-aging agent (1) of the present invention obtained in Example 1. FIG. It is a figure explaining the method for measuring the transfer amount of the antiaging substance for rubber | gum in a vulcanized rubber composition.

<Rubber aging prevention substances>
The anti-aging substance for rubber in the present invention is an organic substance blended for the purpose of preventing the aging of the rubber product and extending its life. Only one type of rubber anti-aging substance may be used, or two or more types may be used in combination.

The anti-aging material for rubber is not particularly limited. For example, amine-based anti-aging material, amine-ketone-based anti-aging material, phenol-based anti-aging material, imidazole-based anti-aging material, sulfur-based anti-aging material, phosphorus-based anti-aging material Prevention substances and the like. Specifically, those described in pages 436 to 443 of “Rubber Industry Handbook <Fourth Edition>” edited by Japan Rubber Association, reaction products of aniline and acetone (TMDQ), synthetic wax (paraffin wax) Etc.), vegetable waxes and the like.

The anti-aging agent for rubber is more likely to migrate in the vulcanized rubber composition as the molecular weight is lower, but the present invention can suppress the migration even with such a low molecular weight anti-aging agent for rubber. . Therefore, in the present invention, an antiaging material for rubber having a relatively low molecular weight (for example, a molecular weight of about 150 to 400) can be used.

As the rubber anti-aging substance, an amine-based anti-aging substance is preferable. Examples of the amine-based anti-aging substance include a compound represented by the formula (I), a compound represented by the formula (II), or a polymer thereof.

(In the formula (I), R ¹ represents a hydrogen atom or an alkyl group having 1 to 13 carbon atoms.)

(In the formula (II), R ² represents a hydrogen atom or an alkyl group having 1 to 13 carbon atoms. R ³ represents a hydrogen atom or an alkoxy group having 1 to 13 carbon atoms.)

The alkyl group having 1 to 13 carbon atoms may be linear or branched, and is preferably branched. The number of carbon atoms is preferably 1 to 10, more preferably 2 to 8, and further preferably 3 to 8. The alkoxy group having 1 to 13 carbon atoms may be linear or branched. The number of carbon atoms is preferably 1 to 10, more preferably 1 to 8, and further preferably 1 to 5.

R ¹ is preferably an alkyl group having 1 to 13 carbon atoms, more preferably a branched alkyl group having 3 to 8 carbon atoms, still more preferably isopropyl or 1,3-dimethylbutyl, and particularly preferably Is 1,3-dimethylbutyl. R ² is preferably a hydrogen atom. R ³ is preferably a hydrogen atom or an alkoxy group having 1 to 5 carbon atoms, more preferably a hydrogen atom or ethoxy.

Examples of the compound represented by the formula (I) include N-isopropyl-N′-phenyl-p-phenylenediamine (IPPD) and N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine. (6PPD). Examples of the compound represented by the formula (II) include 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline (ETMDQ), 2,2,4-trimethyl-1,2-dihydroquinoline and the like. be able to. Examples of the polymer of the compound represented by the formula (II) include poly (2,2,4-trimethyl-1,2-dihydroquinoline) (“Antioxidant FR” manufactured by Matsubara Sangyo Co., Ltd.). Of these, compounds represented by the formula (I) are preferred, and N-isopropyl-N′-phenyl-p-phenylenediamine and N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine are preferred. N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine is more preferable.

<Mesoporous silica with a mesopore volume exceeding 0.81 cm ³ / g>
The composition formula of mesoporous silica is SiO ₂ · nH ₂ O, and the CAS registration number of silica is 7631-86-9. Here, mesoporous silica means silica having mesopores, and mesopores mean pores having a diameter of 2 nm or more and 50 nm or less in the catalyst field in IUPAC.

As the mesoporous silica, those having relatively large mesopores on the surface are preferable. The mesopore diameter of the mesoporous silica is preferably 6 nm or more and 50 nm or less. The diameter of the mesopore is an average value of the diameters of the pores measured by the nitrogen adsorption method (BJH method) under the conditions described in the examples described later.

The mesoporous silica used in the present invention has a mesopore volume exceeding 0.81 cm ³ / g. The pore volume of the mesopores is preferably not more than 0.84 cm ³ / g or more 5.0 cm ³ / g, more preferably not more than 1.0 cm ³ / g or more 5.0 cm ³ / g, particularly preferably Is 1.3 cm ³ / g or more and 5.0 cm ³ / g or less. The pore volume of the mesopores can be measured by a nitrogen adsorption method (BJH method) under the conditions described in Examples described later.

The BET specific surface area of mesoporous silica is preferably 10 m ² / g or more and 550 m ² / g or less, more preferably 20 m ² / g or more and 500 m ² / g or less, and further preferably 25 m ² / g or more and 400 m ² / g or less. . This BET specific surface area can be measured by the method described in Examples described later.

Examples of commercially available mesoporous silica having a mesopore volume exceeding 0.81 cm ³ / g include Fuji Silysia Silicia 310P, 420, and 530, Fuji Silysia Silophobic 100, 507, and 702.

In the rubber anti-aging agent of the present invention, a rubber anti-aging substance is supported on mesoporous silica. In the rubber anti-aging agent of the present invention, the rubber anti-aging substance is preferably supported in the mesopores of mesoporous silica.

The content of mesoporous silica in the rubber anti-aging agent of the present invention is, for example, 0.1 to 100 parts by weight, preferably 0.1 to 50 parts by weight, more preferably 0 to 10 parts by weight of the rubber anti-aging substance. 1 to 30 parts by weight.

<Method for producing anti-aging agent for rubber of the present invention>
The method for producing the anti-aging agent for rubber of the present invention is not particularly limited as long as the anti-aging agent for rubber can be supported on mesoporous silica, and examples thereof include the following method (1) and the following method (2). be able to.

(1) A rubber anti-aging substance is dissolved in a solvent to obtain a solution, and the solution and mesoporous silica are mixed to obtain a mixture. Alternatively, mesoporous silica may be mixed with a solvent to obtain a slurry, and the slurry may be mixed with a solution of an antiaging substance for rubber to prepare a mixture. Next, the solvent is removed from the mixture to obtain the rubber anti-aging agent of the present invention. You may grind | pulverize the obtained anti-aging agent for rubber | gum of this invention as needed. Here, the solvent is not particularly limited as long as it can dissolve the anti-aging substance for rubber and can be distilled off. For example, hydrocarbon solvents such as toluene, xylene, hexane, heptane, acetone, methyl ethyl ketone, etc. And ketone solvents such as methyl isobutyl ketone, and alcohol solvents such as methanol, ethanol and isopropanol.

(2) A rubber anti-aging material is melted to obtain a melt, the melt and mesoporous silica are mixed to obtain a mixture, and the mixture is cooled to obtain the rubber anti-aging agent of the present invention. There is no particular limitation on the method for cooling the mixture, and for example, forced air cooling by blowing or cooling can be employed. You may grind | pulverize the antiaging agent for rubber | gum of this invention obtained after cooling as needed.

In the method (1) and the method (2), the amount of mesoporous silica added is, for example, 0.1 to 100 parts by weight, preferably 0.1 to 100 parts by weight with respect to 10 parts by weight of the rubber anti-aging substance. 50 parts by weight, more preferably 0.1 to 30 parts by weight.

In the obtained anti-aging agent for rubber of the present invention, it can be easily confirmed, for example, by solid NMR measurement that the anti-aging material for rubber is supported on mesoporous silica (particularly in the mesopores). Specifically, for example, the presence or absence of a change in the chemical shift of the peak based on ¹³ C contained in the rubber anti-aging substance may be observed before and after the rubber anti-aging substance is supported on mesoporous silica.
By supporting the rubber anti-aging substance on the mesoporous silica, the interaction between the functional group of the rubber anti-aging substance and the functional group of the mesoporous silica and the rubber anti-aging substance are supported in the mesopores. A change occurs in the three-dimensional structure, and as a result, a change in the chemical shift of the peak based on ¹³ C contained in the anti-aging substance for rubber occurs. And what is necessary is just to confirm that this change exists by solid state NMR measurement. On the other hand, if the rubber anti-aging substance is not supported on the mesoporous silica, the interaction between the functional group of the rubber anti-aging substance and the functional group of the mesoporous silica does not occur, and as a result, it is included in the rubber anti-aging substance. ^No change in peak chemical shift based on ¹³ C occurs. And what is necessary is just to confirm by solid-state NMR measurement that this change does not exist.

<Use of anti-aging agent for rubber of the present invention>
Next, a rubber composition containing the antiaging agent for rubber of the present invention and a rubber component will be described. Only one type of anti-aging agent for rubber of the present invention may be used, or two or more types may be used in combination. Similarly, only 1 type may be used for a rubber component and it may use 2 or more types together. The rubber composition is preferably obtained by kneading the rubber anti-aging agent of the present invention and a rubber component. Kneading can be performed by a known method. The rubber composition may be produced by kneading the rubber anti-aging agent of the present invention and the total amount of rubber component to be used, or the rubber anti-aging agent of the present invention and a part of the rubber component to be used. May be produced by first kneading the master batch and the remaining rubber component. The rubber composition may be a master batch.
The rubber composition may further contain a filler, zinc oxide, stearic acid, a crosslinking agent, a vulcanization accelerator and the like.

The content of the antioxidant for rubber of the present invention in the rubber composition is, for example, 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, more preferably 1 to 1 part by weight with respect to 100 parts by weight of the rubber component. 20 parts by weight.
When the rubber composition is a master batch, the content of the anti-aging agent for rubber of the present invention in the rubber composition is, for example, 1 to 990 parts by weight, preferably 1 to 900 parts by weight with respect to 100 parts by weight of the rubber component. More preferably, it is 1 to 700 parts by weight, particularly preferably 1 to 500 parts by weight.

As a rubber component, for example,
Natural rubber and modified natural rubber (eg, epoxidized natural rubber, deproteinized natural rubber, etc.);
Polyisoprene rubber (IR), styrene / butadiene copolymer rubber (SBR), polybutadiene rubber (BR), acrylonitrile / butadiene copolymer rubber (NBR), isoprene / isobutylene copolymer rubber (IIR), ethylene / propylene-diene copolymer Various synthetic rubbers such as rubber (EPDM) and halogenated butyl rubber (HR);
Can be mentioned.
The rubber component is preferably highly unsaturated, and natural rubber, modified natural rubber, styrene / butadiene copolymer rubber, and polybutadiene rubber are more preferable, and natural rubber is more preferable. Moreover, you may use together the above-mentioned various rubber | gum. Examples of combined use include use of natural rubber and styrene / butadiene copolymer rubber, use of natural rubber and polybutadiene rubber, and the like.

Examples of the natural rubber include grades of natural rubber such as RSS # 1, RSS # 3, TSR20, and SIR20.
Examples of the epoxidized natural rubber include those having a degree of epoxidation of 10 mol% to 60 mol% (specifically, for example, ENR25, ENR50, etc. manufactured by Kumpoulan Guthrie).
Examples of the deproteinized natural rubber include deproteinized natural rubber having a total nitrogen content of 0.3% by weight or less.
Examples of other modified natural rubbers include, for example, 4-vinylpyridine, N, N-dialkylaminoethyl acrylate (specifically, for example, N, N-diethylaminoethyl acrylate), 2-hydroxy acrylate, etc. Examples thereof include a modified natural rubber containing a polar group obtained by reaction.

Examples of the styrene / butadiene copolymer rubber (SBR) include emulsion polymerization SBR and solution polymerization SBR described in pages 210 to 211 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Can be mentioned.

As the rubber for tread, for example, solution polymerization SBR can be preferably mentioned. Further, for example, solution polymerization SBR in which molecular ends are modified using 4,4′-bis- (dialkylamino) benzophenone such as “Nipol (registered trademark) NS116” manufactured by Nippon Zeon Co., Ltd., “SL574” manufactured by JSR, etc. Polymerized SBR with molecular ends modified using a tin halide compound of No. 1, commercial products of silane-modified solution polymerized SBR such as “E10” and “E15” manufactured by Asahi Kasei Co., Ltd., lactam compounds, amide compounds, urea compounds, N, N -A dialkylacrylamide compound, an isocyanate compound, an imide compound, a silane compound having an alkoxy group (for example, trialkoxysilane) and an aminosilane compound alone, or a tin compound, an alkylacrylamide compound, and a silane compound having an alkoxy group Using two or more different compounds such as More preferred examples include solution polymerization SBR having nitrogen, tin, silicon, or a plurality of these elements at the molecular terminals obtained by modifying the molecular terminals.
Further, oil-added SBR in which oil such as process oil and aroma oil is added after emulsion polymerization SBR and solution polymerization SBR can be preferably exemplified as a rubber for tread.

Examples of the polybutadiene rubber (BR) include solution polymerization BR such as a high cis BR having 90% or more of cis 1,4 bond and a low cis BR having a cis bond of around 35%. Preferably, for example, low cis BR having a high vinyl content can be used. Further, for example, tin-modified BR such as “Nipol (registered trademark) BR 1250H” manufactured by Nippon Zeon, 4,4′-bis- (dialkylamino) benzophenone, tin halide compound, lactam compound, amide compound, urea compound, An N, N-dialkylacrylamide compound, an isocyanate compound, an imide compound, a silane compound having an alkoxy group (trialkoxysilane compound, etc.), an aminosilane compound alone, or a tin compound, an alkylacrylamide compound, an alkoxy group More preferable is a solution polymerization BR or the like having any one of nitrogen, tin, silicon, or a plurality of these elements at the molecular ends obtained by modifying the molecular ends using two or more different compounds such as silane compounds having Can be mentioned.

These BRs can be preferably cited as tread rubber or sidewall rubber. In addition, BR is normally used by the blend with SBR and / or natural rubber. As for the ratio of BR, in the case of rubber for treads, for example, SBR and / or natural rubber is 60 to 100% by weight and BR is 40 to 0% by weight with respect to the total rubber weight. In the case of sidewall rubber, for example, SBR and / or natural rubber is 10 to 70% by weight, BR is 90 to 30% by weight, preferably natural rubber is 40 to 60% by weight based on the total rubber weight. %, BR is 60 to 40% by weight. A blend of modified SBR and non-modified SBR, and blend of modified BR and non-modified BR are also preferred.

Examples of the filler include carbon black, silica, talc, clay, titanium oxide and the like that are usually used in the rubber field. Preferably, carbon black, silica, etc. are mentioned, for example. More preferably, carbon black etc. can be mentioned, for example.

Examples of carbon black include those described on page 494 of the “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Preferably, for example, HAF (High-Abrasion-Furnace), SAF (Super-Abrasion-Furnace), ISAF (Intermediate-Surf), FEF (Fast-Extrusion-Furnace), MAF (Medium-Abrasion-Furnace), GPF (General-Purpose-Furnace) -SRF (SRF) Carbon black such as Reinforcing (Furnace).

In the case of a tire tread rubber composition, a CTAB (Cetyl Tri-methyl Ammonium Bromide) specific surface area of 40 m ² / g to 250 m ² / g, a nitrogen adsorption specific surface area of 20 m ² / g to 200 m ² / g, and a particle diameter of 10 nm to A preferred example is 50 nm carbon black. More preferable examples include carbon black having a CTAB specific surface area of 70 m ² / g to 180 m ² / g. Specifically, for example, in the ASTM standard, N110, N220, N234, N299, N326, N330, N330T, N339, N343, N351 and the like can be mentioned. A surface-treated carbon black in which 0.1 to 50% by weight of silica is attached to the surface of the carbon black can also be preferably exemplified. More preferably, for example, a combination of several kinds of fillers such as a combination of carbon black and silica is used.
In the case of the tire tread rubber composition, for example, carbon black alone and both carbon black and silica can be preferably exemplified.

In the case of the rubber composition for carcass and the rubber composition for sidewall, carbon black having a CTAB specific surface area of 20 m ² / g to 60 m ² / g and a particle diameter of 40 nm to 100 nm can be preferably exemplified. Specifically, for example, in the ASTM standard, N330, N339, N343, N351, N550, N568, N582, N630, N642, N660, N662, N754, N762 and the like can be mentioned.

Examples of the silica used as the filler include silica having a CTAB specific surface area of 50 m ² / g to 180 m ² / g, silica having a nitrogen adsorption specific surface area of 50 m ² / g to 300 m ² / g, and the like. Specifically, for example, “AQ” and “AQ-N” manufactured by Tosoh Silica Co., Ltd., “Ultra Gil (registered trademark) VN3”, “Ultra Gil (registered trademark) 360”, and “Ultra Gil (registered trademark)” manufactured by Degussa. 7000 ”,“ Zeosil (registered trademark) 115GR ”,“ Zeosil (registered trademark) 1115MP ”,“ Zeosil (registered trademark) 1205MP ”,“ Zeosil (registered trademark) Z85MP ”manufactured by Rhodia, (Registered trademark) AQ "and the like. Further, for example, silica having a pH of 6 to 8, silica containing 0.2 to 1.5% by weight of sodium, true spherical silica having a roundness of 1 to 1.3, silicone oil such as dimethyl silicone oil, ethoxy It is also preferable to blend an organosilicon compound containing a silyl group, silica surface-treated with an alcohol such as ethanol or polyethylene glycol; a mixture of two or more types of silica having different nitrogen adsorption specific surface areas; and the like.

When the filler is used, the amount used is not particularly limited, but is 5 to 120 parts by weight, preferably 5 to 100 parts by weight, and more preferably 10 to 100 parts by weight with respect to 100 parts by weight of the rubber component. 100 parts by weight. When only carbon black is used as the filler, the amount of carbon black used is preferably 30 to 80 parts by weight with respect to 100 parts by weight of the rubber component. When carbon black and silica are used in combination as fillers, the amount of carbon black used is, for example, 5 to 60 parts by weight, preferably 5 to 50 parts by weight with respect to 100 parts by weight of the rubber component. Examples of the weight ratio of silica / carbon black include a range of 0.7 / 1 to 1 / 0.1.

When silica is used as the filler, bis (3-triethoxysilylpropyl) tetrasulfide (Degussa “Si-69”), bis (3-triethoxysilylpropyl) disulfide (Degussa “Si-75”) )), Bis (3-diethoxymethylsilylpropyl) tetrasulfide, bis (3-diethoxymethylsilylpropyl) disulfide, octanethioic acid S- [3- (triethoxysilyl) propyl] ester (“3-octanoylthio” “NXT silane” manufactured by General Electronic Silicons Co., Ltd.), octanethioic acid S- [3- (2- {3- [2- (3-mercaptopropyl) -4,4,6-trimethyl] [1,3,2] Dioxacillinan-2-yloxy] -1,1-dimethyl Toxi} -4,4,6-trimethyl [1,3,2] dioxacillinan-2-yl) propyl] ester, octanethioic acid S- [3- (2- {3- [2- (3-mercaptopropyl)- 4-methyl [1,3,2] dioxacillinan-2-yloxy] butoxy} -4-methyl [1,3,2] dioxacillinan-2-yl) propyl] ester, undecanethioic acid S- [3- (2- {3- [2- (3-Mercaptopropyl) -4-methyl [1,3,2] dioxacillinan-2-yloxy] butoxy} -4-methyl [1,3,2] dioxacillinan-2-yl) propyl] Esters, octanethioic acid S- [3-((3-hydroxy-2-methylpropoxy) {3-[{3-[(3-hydroxy-2-methylpropoxy) (3-mercaptopropi ) Methylsilanyloxy] -2-methylpropoxy} methyl (3-octanoylsulfanylpropyl) silanyloxy] -2-methylpropoxy} methylsilanyl) propyl] ester, octanethioic acid S- [3-((3-hydroxy-2- Methylpropoxy) {3-[{3-[(3-hydroxy-2-methylpropoxy) (3-mercaptopropyl) methylsilanyloxy] -2-methylpropoxy} (3-mercaptopropyl) methylsilanyloxy]- 2-methylpropoxy} methylsilanyl) propyl] ester, octanethioic acid S- [3-((3-hydroxy-2-methylpropoxy) {3-[{3- [bis (3-hydroxy-2-methylpropoxy) (3 -Mercaptopropyl) silanyloxy] -2-methylpropoxy} (3-merca Ptopropyl) (3-hydroxy-2-methylpropoxy) silanyloxy] -2-methylpropoxy} (3-hydroxy-2-methylpropoxy) silanyl) propyl] ester, phenyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane , Methyltriacetoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, vinyltrimethoxysilane, Vinyltriethoxysilane, vinyltri (methoxyethoxy) silane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, 3-methacryloxy Propyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, (3-glycidoxypropyl) trimethoxysilane, (3-glycidoxypropyl) triethoxysilane, 2- (3,4-epoxycyclohexyl) ) One or more selected from the group consisting of ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane Bondable with silica such as silane coupling agent Motomata is sometimes referred to as the compound having a functional group (e.g., an alkoxysilyl group, etc.) (hereinafter "silica capable of binding compound." ) Is preferably added. Among compounds capable of binding to silica, bis (3-triethoxysilylpropyl) tetrasulfide (“Si-69” manufactured by Degussa), bis (3-triethoxysilylpropyl) disulfide (“Si-75 manufactured by Degussa) “), 3-octanoylthiopropyltriethoxysilane (“ NXT silane ”manufactured by General Electronic Silicones) is preferred.

The addition timing of the compound capable of binding to silica is not particularly limited, but it is preferable to add to the rubber at the same time as silica. The blending amount is, for example, 2 to 10 parts by weight, preferably 7 to 9 parts by weight with respect to 100 parts by weight of silica.

Examples of the compounding temperature when compounding a compound capable of binding to silica with rubber include 80 ° C. to 200 ° C., for example. Preferably, for example, 110 ° C. to 180 ° C. may be mentioned.

When silica is used as the filler, for example, in addition to silica and a compound capable of binding to silica, monohydric alcohols such as ethanol, butanol and octanol; ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene Polyhydric alcohols such as glycol, pentaerythritol, and polyether polyols; N-alkylamines; amino acids; liquid polybutadienes whose molecular ends are carboxyl-modified or amine-modified;

When zinc oxide is used, the amount used is, for example, 1 to 15 parts by weight, preferably 1 to 8 parts by weight with respect to 100 parts by weight of the rubber component.

When stearic acid is used, the amount used is, for example, 0.5 to 10 parts by weight, preferably 1 to 5 parts by weight with respect to 100 parts by weight of the rubber component.

Examples of the crosslinking agent include sulfur. Examples of sulfur include powdered sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, and highly dispersible sulfur. Of these, powdered sulfur is preferred. Further, when the vulcanized rubber composition is used for a tire member having a large amount of sulfur such as a belt member, for example, insoluble sulfur is preferable. Note that the sulfur does not contain a vulcanization accelerator. The amount of sulfur used is, for example, 0.3 to 5 parts by weight, preferably 0.5 to 3 parts by weight with respect to 100 parts by weight of the rubber component.

Examples of the vulcanization accelerator include thiazole vulcanization accelerators and sulfenamide vulcanization accelerators described in pages 412 to 413 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. And guanidine vulcanization accelerators.

Specifically, for example, N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N-tert-butyl-2-benzothiazolylsulfenamide (BBS), N, N-dicyclohexyl-2- Examples include benzothiazolylsulfenamide (DCBS), 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), and diphenylguanidine (DPG). Also, morpholine disulfide, which is a known vulcanizing agent, can be used.

When carbon black is used as the filler, for example, N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N-tert-butyl-2-benzothiazolylsulfenamide (BBS), N, N It is preferable to use either dicyclohexyl-2-benzothiazolylsulfenamide (DCBS) or dibenzothiazyl disulfide (MBTS) and diphenylguanidine (DPG).

When silica and carbon black are used in combination as fillers, for example, N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N-tert-butyl-2-benzothiazolylsulfenamide (BBS) N, N-dicyclohexyl-2-benzothiazolylsulfenamide (DCBS) or dibenzothiazyl disulfide (MBTS) is preferably used in combination with diphenylguanidine (DPG).

The weight ratio of sulfur and vulcanization accelerator is not particularly limited, and examples thereof include sulfur / vulcanization accelerator = 2/1 to 1/2.
EV vulcanization in which the weight ratio of sulfur / vulcanization accelerator is 1 or less, which is a method for improving heat resistance in a rubber member mainly composed of natural rubber, is preferably used in applications where heat resistance needs to be improved.

In addition, various compounding agents usually used in the rubber field may be blended. Compounding agents include, for example, oils; fatty acids such as stearic acid; Coumarone resin G-90 (softening point 80 ° C. to 100 ° C.) manufactured by Nikkaku Chemical, and process resin AC8 (softening point 95 ° C.) manufactured by Kobe Oil Chemical Co., Ltd. ), Etc .; Terpene resins such as terpene resin, terpene / phenol resin, aromatic modified terpene resin; “Nikanol (registered trademark) HP-100” manufactured by Mitsubishi Gas Chemical Co., Ltd. (softening point 105 to 125 ° C.) Xylene / formaldehyde resins such as “Ester gum” series and “Neotor” series manufactured by Arakawa Chemical Co., Ltd .; Hydrogenated rosin derivatives; Novolac alkylphenol resins; Resole alkylphenol resins; C5 petroleum resins; Liquid polybutadienes; Can be mentioned.

Examples of the oil include process oil and vegetable oil. Examples of the process oil include paraffinic process oil, naphthenic process oil, and aromatic process oil.

<Vulcanized rubber composition containing anti-aging agent for rubber of the present invention>
The vulcanized rubber composition containing the antiaging agent for rubber of the present invention is usually obtained by heat-treating a rubber composition obtained by kneading the antiaging agent for rubber of the present invention, a rubber component and a crosslinking agent. Examples of temperature conditions in the heat treatment include 120 ° C. to 180 ° C. The heat treatment may be usually performed at normal pressure or under pressure.

The vulcanized rubber composition containing the rubber anti-aging agent of the present invention is suitably used for tires. Examples of the tire include a pneumatic tire and a solid tire.
Further, the vulcanized rubber composition containing the rubber anti-aging agent of the present invention is a tire comprising a steel cord coated with each member constituting the tire (for example, a vulcanized rubber composition containing the rubber anti-aging agent of the present invention). Sidewall for tires comprising a belt for tires, a carcass for tires containing a carcass fiber cord coated with a vulcanized rubber composition containing an antioxidant for rubber of the present invention, and a vulcanized rubber composition containing an antioxidant for rubber of the present invention , Tire inner liner, tire cap tread or tire under tread).

The vulcanized rubber composition containing the antiaging agent for rubber of the present invention can extend the life of rubber materials such as tires. Further, the vulcanized rubber composition can be used not only for the above-mentioned tire use but also as an anti-vibration rubber for automobiles such as an engine mount, a strut mount, a bush, and an exhaust hanger.

EXAMPLES Hereinafter, although an Example, a reference example, a comparative example, etc. are given and this invention is demonstrated concretely, this invention is not limited to these.
<Rubber aging prevention substances>
A1: Antigen 6C (N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine) manufactured by Sumitomo Chemical Co., Ltd.
<Mesoporous silica>
B1: Silicia 310P manufactured by Fuji Silysia
B2: Silicia 420 manufactured by Fuji Silysia
B3: Silicia 530 manufactured by Fuji Silysia
X1: God ball B-6C made by Suzuki Yushi Co., Ltd.
X2: Silicia 710 manufactured by Fuji Silysia
X3: Silicia 730 manufactured by Fuji Silysia

Example 1 (Production Example of Anti-aging Agent for Rubber of the Present Invention)
A 500 mL beaker is charged with 20 g of mesoporous silica (B1), and 200 mL of methanol is added thereto to form a slurry liquid. On the other hand, 20 g of rubber anti-aging substance (A1) was charged into a 100 mL Erlenmeyer flask, and 50 mL of methanol was added thereto to obtain a methanol solution. A washing solution produced by adding a methanol solution of the rubber anti-aging substance (A1) to a silica gel slurry beaker prepared in advance and washing the 100 mL Erlenmeyer flask containing the methanol solution with 20 mL of methanol. Was added to obtain a mixture. The resulting mixture was stirred at 25 ° C. under air for 1 day. After the stirring was completed, the resulting mixture was dried by an evaporator to obtain an antiaging agent for rubber of the present invention (1) as a gray solid.

Example 2 (Production Example of Anti-aging Agent for Rubber of the Present Invention)
An anti-aging agent (2) for rubber of the present invention was obtained in the same manner as in Example 1 except that the mesoporous silica (B1) was changed to the mesoporous silica (B2).

Example 3 (Production example of the anti-aging agent for rubber of the present invention)
The rubber anti-aging agent (3) of the present invention was obtained in the same manner as in Example 1 except that the mesoporous silica (B1) was changed to the mesoporous silica (B3).

Comparative Example 1 (Production example of rubber anti-aging agent outside the scope of the present invention)
Except that the mesoporous silica (B1) was changed to the mesoporous silica (X1), in the same manner as in Example 1, a rubber anti-aging agent (hereinafter referred to as “(X1) supported rubber anti-aging agent” outside the scope of the present invention. Described).

Reference Example 1 (Production example of rubber anti-aging agent outside the scope of the present invention)
Except that the mesoporous silica (B1) was changed to the mesoporous silica (X2), in the same manner as in Example 1, a rubber anti-aging agent (hereinafter referred to as “(X2) supported rubber anti-aging agent” outside the scope of the present invention. Described).

Reference Example 2 (Production example of rubber anti-aging agent outside the scope of the present invention)
Except that the mesoporous silica (B1) is changed to the mesoporous silica (X3), the rubber anti-aging agent (hereinafter referred to as “(X3) supported rubber anti-aging agent” outside the scope of the present invention is the same as in Example 1. Described).

Mesoporous silicas (B1) to (B3) used in Examples 1 to 3 and mesoporous silicas (X1) to (X3) used in Comparative Example 1 and Reference Examples 1 and 2, respectively, These BET specific surface areas were measured under the following conditions. The results are shown in Table 1.

[Measurement conditions of BET specific surface area, mesopore diameter and pore volume of mesoporous silica]
Measuring device: BELSORP-mini (manufactured by Nippon BEL Co., Ltd.)
Pretreatment device: BELPREP-vacII (manufactured by Nippon BEL Co., Ltd.)
Test method: Nitrogen adsorption method Pretreatment method: Vacuum degassing at 120 ° C. for 8 hours Measurement method: Measurement of adsorption / desorption isotherm by nitrogen using constant volume method Adsorption temperature: 77K
Adsorbate: Nitrogen saturated vapor pressure: Measured adsorbate cross section: 0.162 nm ²
Equilibrium waiting time: 500 sec
Specific surface area: calculated by BET method Mesopore diameter: calculated by BJH method Mesopore pore volume: calculated by BJH method

The BET specific surface area was calculated by subjecting the measurement results obtained under the above conditions to a specific surface area analysis by the BET method. Moreover, said equilibrium waiting time is a waiting time after reaching an adsorption equilibrium state.

<Confirmation of loading of rubber anti-aging agent on mesoporous silica by solid state NMR measurement>
The antiaging agent for rubber of the present invention (1) obtained in Example 1 was subjected to solid state NMR measurement under the following conditions. The results are shown in FIGS.
Comparison of before and after loading of rubber anti-aging material on mesoporous silica showed a change in the chemical shift of the peak based on ¹³ C contained in rubber anti-aging material, so that rubber anti-aging material on mesoporous silica was observed. Was confirmed.

[Solid state NMR measurement conditions]
Device: ECA400 [manufactured by JEOL Ltd.]
MAS: 6kHz
Measurement: ¹³ C CPMAS
contact time: 2ms
Integration: 10,000 times

Reference Example 3 (Production Example of Basic Rubber Composition)
A 10-liter kneader was charged with 50 parts by weight of each of commercially available natural rubber (product name: SMR-CV60) and butadiene rubber (product name: JSR BR01, manufactured by JSR Corporation) and kneaded for 2 minutes. After adding materials other than natural rubber and butadiene rubber shown in Table 2 to the obtained kneaded material, the mixture was further kneaded for 10 minutes to obtain a basic rubber composition. The discharge temperature of the rubber composition from the kneader was 95 ° C.

Comparative Example 2 (Production Example of Vulcanized Rubber Composition not Containing Antiaging Agent for Rubber of the Present Invention)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 A rubber composition was obtained by kneading parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heat-press molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, thickness containing neither an antiaging agent for rubber nor mesoporous silica) 2 mm sheet shape) was obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.
Next, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) A rubber composition was obtained by kneading 0.8 parts by weight, 1.5 parts by weight of sulfur, and 3 parts by weight of an anti-aging agent for rubber (A1) with an open roll machine having a roll set temperature of 60 ° C. . The resulting rubber composition was heat-press molded at 145 ° C. to give a vulcanized rubber composition containing a rubber anti-aging substance and no mesoporous silica (width 15.5 cm, length 16.0 cm, thickness 2 mm). Sheet shape). Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

Reference Example 4 (Method for measuring the migration amount of anti-aging substances for rubber)
Using the two vulcanized rubber compositions obtained in Comparative Example 2, the amount of migration of the rubber anti-aging substance was measured.
Three blank sheets manufactured from a vulcanized rubber composition that does not contain both an antioxidant for rubber and mesoporous silica, and a vulcanized rubber composition that contains an antioxidant for rubber and does not contain mesoporous silica The initial weight of each sheet was measured for three measurement sheets to be measured.
FIG. 3 is a diagram for explaining a method for measuring the amount of migration of the rubber anti-aging substance in the vulcanized rubber composition. After stacking the 6 sheets after the weight measurement (measurement sheets 1 to 3 containing a rubber anti-aging substance, and blank sheets 4 to 6 not containing a rubber anti-aging substance), the entire laminate was made of aluminum. Wrapped with foil 7, and then wrapped with aluminum laminate 8 from above. About 3 kg of weights 9 were placed on the aluminum foil 7 and the aluminum laminate 8 package thus obtained.
The package on which the weight was placed was left in a thermostatic chamber at 25 ° C. for 6 days, then the aluminum foil and the aluminum laminate package were opened, each sheet was taken out, and the weight of each sheet was measured.
The amount of migration of the rubber anti-aging substance was a change in weight from the initial weight of the blank sheet. Separately, as a result of extracting and quantifying the anti-aging agent for rubber from the vulcanized rubber composition of each sheet, it was confirmed that the weight change was caused by the migration of the anti-aging agent for rubber.

Example 4
(Production Example of Vulcanized Rubber Composition Containing Antiaging Agent for Rubber of the Present Invention)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 By kneading, by weight, 1.5 parts by weight of sulfur, and 6 parts by weight of the anti-aging agent for rubber of the present invention (1) obtained in Example 1 with an open roll machine having a roll set temperature of 60 ° C. A rubber composition was obtained. The obtained rubber composition is heated and press-molded at 145 ° C., so that a vulcanized rubber composition containing the antiaging agent for rubber of the present invention (a sheet shape having a width of 15.5 cm, a length of 16.0 cm, and a thickness of 2 mm). Got. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(Production example of vulcanized rubber composition not containing rubber anti-aging substance)
On the other hand, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0 A rubber composition was obtained by kneading 0.8 parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heated and press-molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, sheet thickness 2 mm) containing no rubber anti-aging substance. Obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

Using the vulcanized rubber composition containing the rubber anti-aging agent and the vulcanized rubber composition not containing the rubber anti-aging substance, the amount of migration of the rubber anti-aging substance was measured in the same manner as in Reference Example 4. did.

Example 5
(Production Example of Vulcanized Rubber Composition Containing Antiaging Agent for Rubber of the Present Invention)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 By kneading, by weight, 1.5 parts by weight of sulfur, and 6 parts by weight of the anti-aging agent for rubber of the present invention (2) obtained in Example 2 with an open roll machine having a roll set temperature of 60 ° C. A rubber composition was obtained. The obtained rubber composition is heated and press-molded at 145 ° C., so that a vulcanized rubber composition containing the antiaging agent for rubber of the present invention (a sheet shape having a width of 15.5 cm, a length of 16.0 cm, and a thickness of 2 mm). Got. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(Production example of vulcanized rubber composition not containing rubber anti-aging substance)
On the other hand, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0 A rubber composition was obtained by kneading 0.8 parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heated and press-molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, sheet thickness 2 mm) containing no rubber anti-aging substance. Obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

Using the vulcanized rubber composition containing the rubber anti-aging agent and the vulcanized rubber composition not containing the rubber anti-aging substance, the amount of migration of the rubber anti-aging substance was measured in the same manner as in Reference Example 4. did.

Example 6
(Production Example of Vulcanized Rubber Composition Containing Antiaging Agent for Rubber of the Present Invention)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 By kneading parts by weight, 1.5 parts by weight of sulfur, and 6 parts by weight of the anti-aging agent for rubber of the present invention (3) obtained in Example 3 with an open roll machine having a roll set temperature of 60 ° C, A rubber composition was obtained. The obtained rubber composition is heated and press-molded at 145 ° C., so that a vulcanized rubber composition containing the antiaging agent for rubber of the present invention (a sheet shape having a width of 15.5 cm, a length of 16.0 cm, and a thickness of 2 mm). Got. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(Production example of vulcanized rubber composition not containing rubber anti-aging substance)
On the other hand, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0 A rubber composition was obtained by kneading 0.8 parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heated and press-molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, sheet thickness 2 mm) containing no rubber anti-aging substance. Obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

Using the vulcanized rubber composition containing the rubber anti-aging agent and the vulcanized rubber composition not containing the rubber anti-aging substance, the amount of migration of the rubber anti-aging substance was measured in the same manner as in Reference Example 4. did.

Comparative Example 3
((X1) Production Example of Vulcanized Rubber Composition Containing Anti-aging Agent for Supported Rubber)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 By kneading parts by weight, 1.5 parts by weight of sulfur, and 6 parts by weight of the anti-aging agent for supported rubber (X1) obtained in Comparative Example 1 with an open roll machine having a roll set temperature of 60 ° C., rubber is obtained. A composition was obtained. The obtained rubber composition was hot-pressed at 145 ° C. to obtain a vulcanized rubber composition (sheet having a width of 15.5 cm, a length of 16.0 cm, and a thickness of 2 mm) containing (X1) an anti-aging agent for a supported rubber. Shape). Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(Production example of vulcanized rubber composition not containing rubber anti-aging substance)
On the other hand, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0 A rubber composition was obtained by kneading 0.8 parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heated and press-molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, sheet thickness 2 mm) containing no rubber anti-aging substance. Obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(X1) The amount of migration of the rubber anti-aging substance in the same manner as in Reference Example 4, using the vulcanized rubber composition containing the antioxidant for the supported rubber and the vulcanized rubber composition not containing the anti-aging substance for rubber. Was measured.

Reference Example 5
((X2) Production Example of Vulcanized Rubber Composition Containing Antiaging Agent for Supported Rubber)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 By kneading the weight part, 1.5 parts by weight of sulfur, and 6 parts by weight of the anti-aging agent for supported rubber (X2) obtained in Reference Example 1 with an open roll machine having a roll set temperature of 60 ° C., rubber is obtained. A composition was obtained. The obtained rubber composition was heat-press molded at 145 ° C. to obtain a vulcanized rubber composition (sheet having a width of 15.5 cm, a length of 16.0 cm and a thickness of 2 mm) containing (X2) an anti-aging agent for a supported rubber. Shape). Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(Production example of vulcanized rubber composition not containing rubber anti-aging substance)
On the other hand, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0 A rubber composition was obtained by kneading 0.8 parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heated and press-molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, sheet thickness 2 mm) containing no rubber anti-aging substance. Obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(X2) Amount of migration of rubber anti-aging substance using a vulcanized rubber composition containing an antioxidant for supported rubber and a vulcanized rubber composition not containing an anti-aging substance for rubber in the same manner as in Reference Example 4. Was measured.

Reference Example 6
((X3) Production Example of Vulcanized Rubber Composition Containing Anti-aging Agent for Supported Rubber)
163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0.8 By kneading parts by weight, 1.5 parts by weight of sulfur, and 6 parts by weight of the anti-aging agent for supported rubber (X3) obtained in Reference Example 2 with an open roll machine having a roll set temperature of 60 ° C., rubber is obtained. A composition was obtained. The obtained rubber composition was hot-pressed at 145 ° C. to obtain a vulcanized rubber composition (sheet having a width of 15.5 cm, a length of 16.0 cm and a thickness of 2 mm) containing (X3) an anti-aging agent for a supported rubber. Shape). Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(Production example of vulcanized rubber composition not containing rubber anti-aging substance)
On the other hand, 163.5 parts by weight of the basic rubber composition obtained in Reference Example 3, 2 parts by weight of zinc oxide, and a vulcanization accelerator (N-tert-butyl-2-benzothiazolesulfenamide (TBBS)) 0 A rubber composition was obtained by kneading 0.8 parts by weight and 1.5 parts by weight of sulfur with an open roll machine having a roll set temperature of 60 ° C. The resulting rubber composition was heated and press-molded at 145 ° C. to obtain a vulcanized rubber composition (width 15.5 cm, length 16.0 cm, sheet thickness 2 mm) containing no rubber anti-aging substance. Obtained. Incidentally, between 90% vulcanization of the measured rubber composition in conformity with JIS K 6300-2 to _(t c ₍₉₀₎₎ than the extended 5 minutes time and the vulcanization time.

(X3) Amount of migration of rubber anti-aging substance using a vulcanized rubber composition containing an antioxidant for supported rubber and a vulcanized rubber composition not containing an anti-aging substance for rubber in the same manner as in Reference Example 4. Was measured.

Table 3 shows the compositions of the vulcanized rubber compositions obtained in Examples 4 to 6, Comparative Examples 2 and 3, and Reference Examples 5 and 6, and the composition of the rubber anti-aging agent used. Table 4 shows the transition speed. The unit of numerical values shown in Table 3 is parts by weight. The “migration rate of the rubber anti-aging substance” described in Table 4 includes the rubber anti-aging substance obtained in Comparative Example 2, and the rubber for the vulcanized rubber composition containing no mesoporous silica. This is the relative transfer amount of the anti-aging material for rubber when the transfer amount of the anti-aging material is 100. The smaller the value, the slower the migration rate of the anti-aging material for rubber, which means that the durability of the anti-aging effect in the vulcanized rubber composition is improved.

Reference Example 7 (Production Example of Vulcanized Rubber Composition)
The vulcanized rubber composition obtained by the following first step and second step is suitable for undertread.
<First step>
(Procedure 1)
Using a Banbury mixer (600 mL lab plast mill manufactured by Toyo Seiki Seisakusho), 100 parts by weight of styrene / butadiene copolymer rubber SBR # 1502 (manufactured by Sumitomo Chemical Co., Ltd.), ISAF-HM (manufactured by Asahi Carbon Co., Ltd., product name “Asahi # 80”) ] 35 parts by weight, stearic acid 2 parts by weight, zinc oxide 3 parts by weight, anti-aging agent for rubber of the present invention obtained in Example 1 (1) 8 parts by weight and wax (“OZOACE-0355” manufactured by Nippon Seiwa) 2) 2 parts by weight are kneaded in a range of 160 ° C. to 175 ° C. for 5 minutes at a rotation speed of a mixer of 50 rpm to obtain a rubber composition.
(Procedure 2)
Within a range of 60 ° C. to 80 ° C. with an open roll machine, the rubber composition obtained in Procedure 1 and 2 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide (CBS) as a vulcanization accelerator, A rubber kneaded product is obtained by kneading 0.5 part by weight of diphenylguanidine (DPG) as a vulcanization accelerator, 0.8 part by weight of dibenzothiazyl disulfide (MBTS) as a vulcanization accelerator and 1 part by weight of sulfur. Get.
<Second step>
The rubber kneaded product obtained in the first step (procedure 2) is heat-treated at 145 ° C. to obtain a vulcanized rubber composition.

Reference Example 8 (Production Example of Vulcanized Rubber Composition)
The vulcanized rubber composition obtained by the following first step and second step is suitable for a belt.
<First step>
(Procedure 1)
Using a Banbury mixer (600 mL Lab Plast Mill manufactured by Toyo Seiki Seisakusho), 100 parts by weight of commercially available natural rubber (RSS # 1), 45 parts by weight of HAF (Asahi Carbon Co., Ltd., product name “Asahi # 70”), stearic acid 3 parts by weight, zinc oxide 5 parts by weight, hydrous silica ("Nipsil (registered trademark) AQ" manufactured by Tosoh Silica Co., Ltd.) 10 parts by weight, anti-aging agent for rubber of the present invention (1) obtained in Example 1 (16) A rubber composition is obtained by kneading 2 parts by weight of resorcin and 2 parts by weight of cobalt naphthenate within a range of 160 ° C. to 175 ° C. for 5 minutes at a rotation speed of a mixer of 50 rpm.
(Procedure 2)
In a range of 60 ° C. to 80 ° C. with an open roll machine, the rubber composition obtained in the procedure 1 and 1 weight of N, N-dicyclohexyl-2-benzothiazolesulfenamide (DCBS) as a vulcanization accelerator Parts by weight, 6 parts by weight of sulfur and 3 parts by weight of methoxylated methylol melamine resin (“SUMIKANOL 507AP” manufactured by Sumitomo Chemical Co., Ltd.) to obtain a rubber kneaded product.
<Second step>
The rubber kneaded product obtained in the first step (procedure 2) is heat-treated at 145 ° C. to obtain a vulcanized rubber composition.

Reference Example 9 (Production Example of Vulcanized Rubber Composition)
The vulcanized rubber composition obtained by the following first step and second step is suitable for an inner liner.
<First step>
(Procedure 1)
Using a Banbury mixer (600 mL Lab Plast Mill manufactured by Toyo Seiki Seisakusho), halogenated butyl rubber (“Br-IIR2255” manufactured by ExxonMobil) 100 parts by weight, GPF 60 parts by weight, stearic acid 1 part by weight, zinc oxide 3 parts by weight A rubber composition is obtained by kneading 10 parts by weight of paraffin oil (“Diana Process Oil” manufactured by Idemitsu Kosan Co., Ltd.) within a range of 160 ° C. to 175 ° C. for 5 minutes at a rotation speed of a mixer of 50 rpm.
(Procedure 2)
In the range of 60 ° C. to 80 ° C. with an open roll machine, the rubber composition obtained in Procedure 1, the anti-aging agent for rubber of the present invention (1) obtained in Example 1, 2 parts by weight, and a vulcanization accelerator A rubber kneaded material is obtained by kneading 1 part by weight of a certain dibenzothiazyl disulfide (MBTS) and 2 parts by weight of sulfur.
<Second step>
The rubber kneaded product obtained in the first step (procedure 2) is heat-treated at 145 ° C. to obtain a vulcanized rubber composition.

Reference Example 10 (Production Example of Vulcanized Rubber Composition)
The vulcanized rubber composition obtained by the following first step and second step is suitable for side walls.
<First step>
(Procedure 1)
Using a Banbury mixer (600 mL Lab Plast Mill manufactured by Toyo Seiki Seisakusho), 40 parts by weight of commercially available natural rubber (RSS # 3), 60 parts by weight of polybutadiene rubber (“BR150B” manufactured by Ube Industries), 50 parts by weight of FEF, stearic acid 2.5 parts by weight, zinc oxide 3 parts by weight, anti-aging agent for rubber of the present invention obtained in Example 1 (1) 16 parts by weight, process oil (“NC-140” manufactured by Cosmo Oil Co., Ltd.) 10 parts by weight A rubber composition was prepared by kneading 2 parts by weight of wax (“Sannok (registered trademark) wax” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.) within a range of 160 ° C. to 175 ° C. for 5 minutes at a rotation speed of a mixer of 50 rpm. Get things.
(Procedure 2)
Within the range of 60 ° C. to 80 ° C. with an open roll machine, the rubber composition obtained in Procedure 1 and N-tert-butyl-2-benzothiazolylsulfenamide (BBS) 0.75 as a vulcanization accelerator A rubber kneaded material is obtained by kneading parts by weight and 1.5 parts by weight of sulfur.
<Second step>
The rubber kneaded product obtained in the first step (procedure 2) is heat-treated at 145 ° C. to obtain a vulcanized rubber composition.

Reference Example 11 (Production Example of Vulcanized Rubber Composition)
The vulcanized rubber composition obtained by the following first step and second step is suitable for carcass.
<First step>
(Procedure 1)
Using a Banbury mixer (600 mL Lab Plast Mill manufactured by Toyo Seiki Seisakusho), 70 parts by weight of commercially available natural rubber (TSR20), 30 parts by weight of styrene-butadiene copolymer rubber SBR # 1502 (manufactured by Sumitomo Chemical Co., Ltd.), N339 (Mitsubishi Chemical) 60 parts by weight, stearic acid 2 parts by weight, zinc oxide 5 parts by weight, process oil (“Diana Process PS32” by Idemitsu Kosan Co., Ltd.) 7 parts by weight within a range of 160 ° C. to 175 ° C. for 5 minutes. A rubber composition is obtained by kneading at a rotation speed of a mixer of 50 rpm.
(Procedure 2)
The rubber composition obtained in step 1 and 1 part by weight of N-tert-butyl-2-benzothiazolylsulfenamide (BBS) as a vulcanization accelerator within the range of 60 ° C. to 80 ° C. in an open roll machine A rubber kneaded product is obtained by kneading 3 parts by weight of sulfur and 8 parts by weight of the antiaging agent for rubber of the present invention (1) obtained in Example 1.
<Second step>
The rubber kneaded product obtained in the first step (procedure 2) is heat-treated at 145 ° C. to obtain a vulcanized rubber.

Reference Example 12 (Production Example of Vulcanized Rubber Composition)
The vulcanized rubber composition obtained by the following first step and second step is suitable for cap treads.
<First step>
(Procedure 1)
Using a Banbury mixer (600 mL Laboplast Mill, manufactured by Toyo Seiki Seisakusho), 100 parts by weight of styrene / butadiene copolymer rubber SBR # 1500 (manufactured by JSR), silica (product name: “Ultrasil® VN3-G”) 78.4 parts by weight of Degussa), 6.4 parts by weight of carbon black (product name “N-339” manufactured by Mitsubishi Chemical), silane coupling agent (bis (3-triethoxysilylpropyl) tetrasulfide: product name 6.4 parts by weight of “Si-69” manufactured by Degussa Co., Ltd., 47.6 parts by weight of process oil (product name “NC-140” manufactured by Cosmo Oil Co., Ltd.), anti-aging agent for rubber of the present invention obtained in Example 1 (1) 12 parts by weight, 2 parts by weight of zinc oxide and 2 parts by weight of stearic acid are kneaded in the range of 70 ° C. to 120 ° C. for 5 minutes at a rotation speed of a mixer of 80 rpm. Continuing in the range of 70 ℃ ~ 120 ℃, 5 minutes, by kneading at a rotation speed of 100rpm of mixer to obtain a rubber composition.
(Procedure 2)
Within the range of 30 ° C. to 80 ° C. in an open roll machine, the rubber composition obtained in Procedure 1 and 1 part by weight of N-cyclohexyl-2-benzothiazole sulfenamide (CBS) as a vulcanization accelerator, 1 part by weight of diphenylguanidine (DPG), a vulcanization accelerator, 1.5 parts by weight of wax (product name “Sunnock (registered trademark) N” manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.) and 1.4 parts by weight of sulfur By doing so, a rubber kneaded material is obtained.
<Second step>
The rubber kneaded product obtained in the first step (procedure 2) is heat-treated at 160 ° C. to obtain a vulcanized rubber composition.

Reference Example 13 (Production Example of Vulcanized Rubber Composition)
In Reference Example 12, the same procedure as in Reference Example 12 was used, except that solution-polymerized SBR (“ASAPREN (registered trademark)” manufactured by Asahi Kasei Chemicals) was used instead of styrene-butadiene copolymer rubber SBR # 1500 (manufactured by JSR). Thus, a vulcanized rubber composition is obtained. The resulting vulcanized rubber composition is suitable for cap treads.

Reference Example 14 (Production Example of Vulcanized Rubber Composition)
In Reference Example 12, SBR # 1712 (manufactured by JSR) was used instead of styrene-butadiene copolymer rubber SBR # 1500 (manufactured by JSR), the amount of process oil used was changed to 21 parts by weight, and zinc oxide was charged. A vulcanized rubber composition is obtained in the same manner as in Reference Example 12 except that the timing is changed to Procedure 2. The resulting vulcanized rubber composition is suitable for cap treads.

Even if the anti-aging agent for rubber of the present invention (1) is replaced with the anti-aging agent for rubber of the present invention (2) or the anti-aging agent for rubber of the present invention (3), the vulcanized rubber composition is the same as in Reference Examples 7-14. Things are obtained.

In the vulcanized rubber composition containing the antiaging agent for rubber of the present invention, the durability of the antiaging effect of the antiaging substance for rubber contained therein is improved.

1,2,3 Measurement sheet 4 containing rubber anti-aging substance 4, 5, 6 Blank sheet not containing rubber anti-aging substance 7 Aluminum foil 8 Aluminum laminate 9 Weight

Claims (7)

1. Mesoporous silica having a pore volume of mesopores exceeding 0.81 cm ³ / g;
   A rubber anti-aging agent comprising the rubber anti-aging substance supported on the mesoporous silica.
2. A rubber anti-aging agent obtained by supporting a rubber anti-aging material on mesoporous silica having a mesopore pore volume exceeding 0.81 cm ³ / g.
3. Rubber anti-aging agent according to claim 1 or 2, wherein the pore volume is less than 0.84 cm ³ / g or more 5.0 cm ³ / g of mesopores.
4. In solid state NMR measurement, the peak chemical shift based on ¹³ C contained in the rubber anti-aging substance supported on the mesoporous silica is based on ¹³ C contained in the rubber anti-aging substance not supported on the mesoporous silica. The anti-aging agent for rubber according to any one of claims 1 to 3, wherein the anti-aging agent for rubber is different from the chemical shift of the peak.
5. The rubber anti-aging agent according to any one of claims 1 to 4, wherein the mesoporous silica has a mesopore diameter of 6 nm to 50 nm.
6. 6. The rubber anti-aging agent according to claim 1, wherein the rubber anti-aging substance is a compound represented by the formula (I).
   

   

   (In the formula (I), R ¹ represents a hydrogen atom or an alkyl group having 1 to 13 carbon atoms.)
7. The rubber anti-aging agent according to any one of claims 1 to 6, comprising 0.1 to 100 parts by weight of the mesoporous silica with respect to 10 parts by weight of the rubber anti-aging substance.

Images