From antioxidants to ozone-protective waxes – everything from a single source

a) Aromatic amines (p-phenylenediamines, dihydroquinolines, diphenylamines) 

Examples: 

Sirantox 6PPD, Sirantox IPPD, Sirantox 77PD 

Supplier: 

Sennics 

Technical benefits: 

• Very high protection against thermo-oxidative aging and fatigue 
• Additionally, excellent ozone protection 
• Proven in highly dynamic applications (e.g., tires, technical rubber goods) 

Properties: 

• Strongly discoloring, migration possible 
• Preferred for black or dark compounds 

Typical applications: 

• NR, SBR, BR, NBR, CR, IR – particularly in tires, hoses, conveyor belts, and technical rubber goods 
• 6PPD and IPPD offer pronounced synergy effects, particularly when used in combination. Sirantox 77PD is characterized by high solubility and a lower tendency to bloom, and also offers improved protection against heavy-metal-induced aging. 

Note: 

Despite their high effectiveness, PPD types—especially 6PPD—are increasingly coming under criticism. Aurora AOX 6 from Nordmann partner Ergon International represents an innovative alternative. This new type is based on sustainable raw materials and was developed specifically for industrial rubber applications. 

b) TMQ and diphenylamine derivatives 

Examples: 

Norantox TMQ (trimethyl-dihydroquinoline), Norantox ODPA, Quantox 45

Supplier: 

Nordmann 

These products offer robust long-term protection against thermal aging and have proven particularly effective in technical black compounds. Their tendency to discolor is significantly lower than that of classic PPD types, but higher than that of hindered phenols or benzimidazoles. 

Technical benefits: 

• Robust long-term protection against thermo-oxidative aging
• Good compatibility with many elastomers
• Partially peroxide-stable
• Protection against metal-catalyzed oxidation

Properties: 

• Slightly discoloring, significantly less than PPD
• Low volatility

Typical applications: 

• CR, NR, SBR, BR, NBR, also for technical black compounds
• TMQ and diphenylamine derivatives often represent a balanced compromise between performance and appearance.

c) Steric-hindered phenols 

Examples: 

Norantox 1010, 1076, 1098 

Supplier: 

Nordmann 

Hindered phenols are primarily used for color-stable applications with high demands on long-term performance. These antioxidants effectively protect against thermo-oxidative aging without compromising the color or transparency of the compound. 

Technical benefits: 

• Very effective protection against heat and oxygen aging
• High long-term stability of mechanical properties
• Good compatibility with sulfur and peroxide curing

Properties: 

• Non-staining, no migration
• Low volatility
• Very good extraction resistance

Regulatory advantages: 

• Many grades are FDA- and BfR-compliant and therefore also suitable for sensitive applications such as food contact, drinking water components, or medical-grade products.

Typical applications: 

• EPDM, NBR, HNBR, ACM compounds, light-colored and colored blends, seals, cables, technical articles made of IIR, SBS, SEBS, EPM, EPDM.

Synergy: 

In combination with phosphites (e.g., Norantox 168), the protective effect can be significantly increased. 

d) Benzimidazoles 

Examples: 

Norantox MMBI, ZMMBI 

Supplier: 

Nordmann 

For applications where color and surface stability are paramount, benzimidazole-based antioxidants offer an attractive alternative. 

Technical benefits: 

• Good thermo-oxidative stabilization
• Very low migration
• Ideal as a synergistic partner for PPD or TMQ systems

Properties: 

• Non-staining → suitable for light-colored and colored compounds
• Nitrosamine-free

Special features: 

• Supports storage stability
• Reduces blooming
• Particularly suitable for sulfur-free and peroxide curing systems

These substances break down hydroperoxides, thereby preventing the formation of new, harmful radicals. They complement primary antioxidants and protect them from premature depletion. This significantly increases the overall stability of the compound—especially under thermal stress during processing and in service. 

a) Phosphites 

Example: 

Norantox 168 

Supplier: 

Nordmann 

Phosphites act as effective hydroperoxide scavengers and play a central role in stabilization during processing. In combination with hindered phenols, they exhibit pronounced synergistic effects. They improve storage stability. 

Technical benefits: 

• Decomposition of hydroperoxides
• Protection of primary antioxidants against premature degradation
• Improvement of processing and storage stability

Properties: 

• Non-staining
• Excellent hydrolysis resistance

Typical applications: 

• SBS, SEBS, BR, EPM, EPDM

Note: 

Not suitable for conventional sulfur vulcanization 

b) Dithiocarbamates (nickel types) 

Example: 

Norantox NDBC 

Supplier: 

Nordmann 

Nickel-based dithiocarbamates offer not only protection against thermal aging but also very good light stability. These products are non-staining and are therefore also suitable for light-colored compounds. 

Technical benefits: 

• Excellent protection against heat and light aging
• Very good performance in light-colored compounds

Properties: 

• Non-staining

Typical applications: 

• EPDM, CR, specialty elastomers

Hindered Amine Light Stabilizers (HALS) protect against UV-induced aging and surface defects. 

Examples: 

Norantox UV622, UV770, UV944 

Supplier: 

Nordmann 

Advantages: 

• Very low volatility 
• High thermal stability 
• Excellent protection against UV radiation and long-term heat aging 
• FDA-compliant 

Application: 

• For all common rubber and plastic types, especially where there are increased requirements for light and weather resistance. 

In addition to chemical anti-ozone agents, physically active waxes play an important role in ozone protection, particularly under static stress. They migrate to the surface and form a protective film there that prevents the penetration of ozone. 

Examples: 

Norantox 654, Controzon, Controzon Plus, Controzon S, Controzon W 

Suppliers: 

Nordmann, D. O. G. 

Advantages: 

• Different melting points and paraffin content for various temperature ranges 
• Non-staining 
• FDA- and BfR-compliant 

Typical applications: 

• Tires, conveyor belts, seals, cable jackets – particularly in NR, SBR, CR 

Nordmann’s portfolio of anti-aging agents offers the rubber industry a comprehensive range of products organized by chemical structure. The targeted selection and combination of products enables the creation of tailor-made solutions for every application—from tires and technical products to cables and seals—to improve service life, appearance, and processability. Various supply forms, such as powders, granules, or pellets, also facilitate integration into existing production and mixing processes. Through coordinated synergy concepts, both performance and cost-effectiveness can be optimized. 

Have we piqued your interest? Dr. Gunther Seifert and Dr. Fabian Verheyen are happy to answer any questions you may have.