Tire rubber compounds face continuous oxidative stress and ozone exposure during both manufacturing and service life. Without protection, these compounds experience chain scission and crosslinking reactions that lead to premature aging, with laboratory tests showing up to 40% loss in mechanical properties after accelerated aging at 70°C for 168 hours. Current manufacturing processes must balance protecting the rubber matrix while maintaining critical performance properties.

The fundamental challenge lies in incorporating anti-degradants that provide comprehensive protection against multiple degradation mechanisms while preventing unwanted side effects like blooming, discoloration, and environmental leaching.

This page brings together solutions from recent research—including new p-phenylenediamine derivatives with improved solubility, quinoline-based antioxidant systems, and specialized diamine compounds that resist migration. These and other approaches focus on achieving long-term protection while meeting increasingly strict requirements for environmental impact and tire appearance.

1. Compound with Formula I for Rubber Aging Stabilization and Antiozonant Properties

Continental Reifen Deutschland GmbH, 2024

A compound for use as an aging stabilizer, antiozonant, and dye in rubber products like tires. The compound has the formula I: [1] The compound improves rubber durability by reducing aging and preventing blooming compared to traditional aromatic amine aging stabilizers. It provides sufficient solubility in rubber matrices like natural and synthetic rubbers. The compound has lower hazard potential compared to aromatic amine stabilizers which are suspected carcinogens. The compound can be produced by a process involving steps a) and b) starting from compound A.

2. Tire Rubber Composition with Void-Introducing Agent and Amine-Based Antioxidant

BRIDGESTONE CORPORATION, 2024

Tire rubber composition, tire rubber member, and tire that have improved on-ice performance and breaking resistance despite having voids in the rubber. The composition contains a rubber component, a void-introducing agent, and an amine-based antioxidant. The antioxidant improves aging resistance and prevents rubber property losses after high temperature exposure. This balances the void-introduction benefits for on-ice traction with better overall breaking strength.

3. Rubber Composition with High Purity 6PPD and S-TMQ Quinoline Antidegradant Combination

Sennics Co., Ltd., 2024

Rubber composition with reduced odor and improved aging resistance for tires and other rubber articles. The composition contains a diene elastomer, reinforcing filler, antidegradant, and crosslinker. The antidegradant is a combination of a high purity 6PPD and an S-TMQ quinoline antidegradant. This combination significantly reduces tire odor compared to lower purity 6PPD and regular TMQ. It also improves thermal aging resistance and tension fatigue of the rubber composition with less antidegradant.

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4. Rubber Compound Antidegradant Composition with TMPPD and Select Phenylenediamines

Sennics Co., Ltd., 2024

Antidegradant composition for rubber compounds that improves discoloration and fatigue resistance of tires without using excessive amounts of antidegradants or saturated rubbers. The composition contains a specific combination of antidegradants, namely 2,4,6-tri-(N-1,4-dimethylpentyl-p-phenylenediamine) (TMPPD) and either N-phenyl-N′-(2-methylphenyl)p-phenylenediamine (N3100-B) or N-phenyl-N′-(2,6-dimethylphenyl) p-phenylenediamine (N3100-C). The composition can be used as a masterbatch in rubber compounds or directly added to unvulcanized rubber. This allows reducing the overall amount of

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5. N-Phenyl-N′-Disubstituted Phenyl-p-Phenylenediamine Compound for Rubber with Methyl Substituents

Sennics Co., Ltd., 2024

Low-pollution antidegradant compound for rubber that improves resistance to discoloration of rubber articles while maintaining mechanical and aging properties. The compound has structure N-phenyl-N′-disubstituted phenyl-p-phenylenediamine, where R1 and R2 are methyl. It reduces discoloration compared to pollution-type antidegradants like 6PPD. The low-pollution compound can be used alone or in combination with pollution-type antidegradants in rubber compositions.

6. P-Phenylenediamine Compounds with Alkyl and Cycloalkyl Substituents Synthesized from Aniline and Nitrobenzene Derivatives

Sennics Co.,Ltd., 2024

P-phenylenediamine antidegradant compounds for rubber applications with improved aging resistance. The compounds have novel structures with alkyl, cycloalkyl, or branched alkyl substituents on the phenylenediamine rings. They are synthesized via condensation and reduction reactions starting from aniline and nitrobenzene derivatives. The compounds can be used in rubber compositions to improve thermal oxidative aging and UV aging resistance of rubber products like tires.

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7. p-Phenylenediamine Antidegradants with Branched Alkyl Substituents Synthesized via One-Pot Condensation and Reduction

Sennics Co., Ltd., 2024

A new class of p-phenylenediamine antidegradants for rubber compounds, like tires, with improved ozone and aging resistance compared to traditional p-phenylenediamine antidegradants. The new antidegradants have novel structures with branched alkyl groups on the phenyl rings. They are synthesized using a one-pot condensation and reduction reaction of aniline and nitrobenzene derivatives. The condensation uses a base catalyst and the reduction uses a metal catalyst like Raney nickel. The new antidegradants can be used in rubber compositions to improve thermal oxidative aging and UV resistance of rubber products like tires.

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8. Rubber Composition with Specific Diamine and Quinoline Antioxidant for Ozone-Resistant, Non-Discoloring Tires

Toyo Tire Corporation, 2024

Rubber composition for tires that provides ozone resistance without discoloration of the tire surface. The composition contains a diene-based rubber, a filler, a specific diamine compound, and a quinoline-based antioxidant. It omits the commonly used diamine antioxidants IPPD and 6PPD that can transfer to the tire surface and cause discoloration. The replacement diamine compound improves ozone resistance without mobility issues.

9. Rubber Composition with Diene Rubber, Silica Filler, and Specific Antioxidant and Vulcanization Additives

Toyo Tire Corporation, 2024

Rubber composition for tires that provides excellent low heat generation, aging resistance, and ozone resistance, without using common antioxidants like IPPD and 6PPD. The composition contains a diene rubber, filler (silica), phenylenediamine, quinoline-based antioxidant, and N-cyclohexyl-2-benzothiazolylsulfenamide vulcanization accelerator. The silica content is limited to 70% or less based on total filler. This allows sufficient antioxidant effectiveness without adsorbing to the silica.

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10. Compounds with Multiple Organic Thiosulfate Groups Represented by S,S′,S″-((1,3,5-Triazinane-1,3,5-Triyl)Tris(R1-1,1-Diyl)) Tris(Sulfurothioate)

Flexsys America L.P., 2024

Compounds with multiple organic thiosulfate groups for improving aging, adhesion, and vulcanization properties in rubber compositions. The compounds are represented by formula I: S,S′,S″-((1,3,5-triazinane-1,3,5-triyl)tris(R1-1,1-diyl)) tris(sulfurothioate), where R1 is a methyl, ethyl, or propyl group. These compounds can be made by reacting a haloalkylamine hydrohalide with a metal thiosulfate to form a Bunte salt, followed by deprotonation and reaction with an aldehyde. They can be used in vulcanizable elastomeric formulations at 0.1-5 parts per 100 parts elastomer to improve aging, adhesion, and

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11. Phenothiazine Derivative with Branched Alkyl Amino Group for Aging Stabilization in Rubber Mixtures

Continental Reifen Deutschland GmbH, 2024

Compound, rubber mixture, tire, and process for aging stabilization of rubber articles like tires. The compound is a phenothiazine derivative with a branched alkyl amino group. It is an alternative to aromatic amine aging stabilizers like 6PPD. The compound improves aging stability and reduces blooming compared to aromatic amines. It can be used in rubber compounds at 0.1-60 phr. The rubber mixture contains the compound instead of or along with other aging stabilizers. The tire can have the compound-containing rubber in components like the tread. The compound can be made by reacting 3-aminophenothiazine with a branched alkyl amine.

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12. Rubber Composition with Enhanced Heat Aging Resistance Containing Filler, Vulcanizing Agent, and Antiaging Additives

Toyo Tire Corporation, 2023

Rubber composition that improves the heat aging resistance of a resultant vulcanized rubber. The composition includes a vulcanized rubber of the rubber composition, a filler, a vulcanizing agent, a vulcanization accelerator, an antiaging agent, a softener such as wax or oil, a processing aid, and a rubber component.

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13. Tire with Crosslinked Elastomeric Sidewalls Containing High-Loading Phenolic Antioxidant

PIRELLI TYRE S.p.A., 2022

Tire with improved resistance to ozone cracking on the sidewalls. The tire has a crosslinked elastomeric composition containing a high loading of phenolic antioxidant (3 phr or more) to protect against ozone without using waxes or other static protective agents. This prevents staining and coloration issues on the sidewalls. The phenolic antioxidant offers sufficient ozone protection without the blooming and migration issues of waxes.

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14. Rubber Compound with Formula (I) Structure Incorporating R, R1, and R2 Substituents for Enhanced Anti-Aging and Discoloration Resistance

Sennics Co., Ltd., 2022

Compound with improved anti-aging and discoloration resistance for rubber applications like tires. The compound has a specific structure represented by formula (I) with R, R1, and R2 substituents. It provides longer-lasting anti-aging protection compared to existing agents and reduces discoloration compared to conventional anti-aging compounds. The compound can be used as an anti-aging agent in rubber products like tires to prevent aging and deterioration from factors like light, heat, oxygen, and fatigue during use.

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15. Sulfur-Crosslinked Rubber Mixture with Additives for Enhanced Aging and Cracking Resistance

Continental Reifen Deutschland GmbH, 2022

Sulfur-crosslinked rubber mixture for vehicle tires that improves aging and cracking resistance. The mixture contains specific additives like para-phenylenediamine, dihydroquinoline, and anti-reversion agents. The mixture can have network node spacing via defined numbers of sulfur atoms or efficient vulcanization systems. The additive amounts and ratios provide improved reversion stability and cracking properties after aging. The mixture can be used in tire components like the flange profile to optimize durability.

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16. Rubber Composition Incorporating Diene-Based Polymer, Alkylated Hydroquinone, and Amine Anti-Aging Agent

BRIDGESTONE CORPORATION, 2022

Rubber composition for tires and other rubber products that provides both high mechanical strength and excellent ozone crack resistance. The composition contains a diene-based rubber, a hydroquinone compound with a 4-6 carbon alkyl group, and an amine-based anti-aging agent. The hydroquinone compound improves ozone crack resistance while maintaining vulcanization properties. The amine-based anti-aging agent prevents deterioration. The composition allows making tires with both high strength and ozone resistance.

17. Rubber Antidegradant Composition with TMPPD, N3100-B, and N3100-C for Masterbatch Integration

Sennics Co., Ltd., 2022

Antidegradant composition for rubber compounds that improves discoloration, fatigue resistance, and aging performance of rubber articles like tires. The composition contains a specific combination of antidegradants: TMPPD, N3100-B, and N3100-C. The composition can be used directly in rubber compounds or as a masterbatch with a diene elastomer. The masterbatch formulation has the antidegradant composition plus optional additives like forming agent and bonding agent. The antidegradant composition and masterbatch promote rubber properties like fatigue resistance, discoloration resistance, and ozone resistance. The masterbatch further improves fatigue resistance compared to directly adding the antidegradant composition.

18. Pneumatic Tire with Belt Pad Rubber Composition Incorporating N,N-Dibenzylbenzothiazole-2-Sulfenamide and Specific Additives for Enhanced Heat Aging and Crack Growth Resistance

Toyo Tire Corporation, 2021

Pneumatic tire with improved heat aging resistance and crack growth resistance of the belt pad while reducing the use of raw materials that can have environmental impacts. The tire uses a rubber composition for the belt pad that contains a specific vulcanization accelerator (N,N-dibenzylbenzothiazole-2-sulfenamide) and additional compounds (1,6-bis(N,N-dibenzylthiocarbamoyldithio)hexane and hexamethylene bis-thiosulfate disodium salt dihydrate) to significantly improve heat aging and crack growth resistance compared to traditional compositions. This allows the belt pad to maintain rigidity and prevent failure even after aging and repetitive loading, without needing cobalt compounds that have environmental concerns.

19. p-Phenylenediamine Antidegradant with Alkyl Substituents for Reduced Discoloration in Rubber Compositions

Sennics Co, Ltd., 2021

Low-pollution antidegradant compound for rubber compositions that reduces discoloration of rubber articles without sacrificing aging properties. The compound is a p-phenylenediamine antidegradant with the structure N-[R1-C6-R2]-N'-C6H5, where R1 and R2 are alkyl groups. The compound improves resistance to discoloration of rubber articles compared to conventional pollution-type antidegradants like 6PPD. It can be used alone or with additional antidegradants in rubber compositions for tires, belts, etc. to reduce discoloration while maintaining aging properties.

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20. Method for Producing Oxidation Resistant Natural Rubber via Antioxidant Binding in Latex Stage

Cooper Tire and Rubber Company, 2021

A method to produce oxidation resistant natural rubber from sources like guayule that involves chemically binding antioxidants to the rubber in the latex stage before extracting resins. This prevents the antioxidants from being removed during resin extraction. The antioxidant, like MADA, reacts with the rubber in the latex via a free radical addition reaction where the sulfur group becomes bound to the rubber backbone. This bound antioxidant resists extraction during resin removal steps. This allows producing oxidation resistant rubber with lower residual proteins and resins compared to traditional extraction methods.

21. Rubber Compound Incorporating Terpene-Modified Lignin as Antioxidant

22. Antidegradant Composition with Methyl, Ethyl, Isobutyl, and Cyclohexyl Components for Rubber Articles

23. N-Phenyl-N′-Disubstituted Phenyl-p-Phenylenediamine Antidegradant Compound for Rubber

24. Rubber Composition Anti-Degradant with Multi-Compound Structure for Enhanced Aging Resistance

25. Salts of Anti-Degradation Compounds for Tire Elastomers with Reduced Volatility and Enhanced Surface Uniformity

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