Antioxidants

Antioxidants are functional chemical additives widely used to protect polymers, rubber, plastics, lubricants, coatings, and other materials from oxidative degradation. By reducing the effects of oxygen, heat, and processing conditions, antioxidants help maintain the physical and chemical properties of materials during processing, storage, and long-term use.

Polymer antioxidants are particularly important in the plastics, rubber, tire, adhesives, coatings, and polymer industries, where exposure to heat, oxygen, mechanical stress, and processing conditions can cause material degradation.

Different antioxidant chemistries are available for different polymer systems and applications. Product selection depends on the polymer type, processing temperature, formulation, required performance, and regulatory requirements.

Antioxidant Product Types

Antioxidants can generally be divided into several categories according to their chemical structure and mode of action.

Primary Antioxidants

Primary antioxidants, also known as chain-breaking antioxidants, primarily react with free radicals generated during polymer oxidation. They help interrupt oxidative chain reactions and protect the polymer from degradation.

Common primary antioxidant families include:

• Hindered phenolic antioxidants
• Aromatic amine antioxidants
• Other radical-scavenging antioxidants

They are widely used in plastics, rubber, adhesives, coatings, and other polymer formulations.

Secondary Antioxidants

Secondary antioxidants help decompose hydroperoxides formed during polymer oxidation. They are often used together with primary antioxidants to provide synergistic long-term protection.

Common secondary antioxidant families include:

• Phosphite antioxidants
• Phosphonite antioxidants
• Thioester antioxidants

These products are frequently used in polymer processing and plastic stabilization.

Antioxidant Blends

Antioxidant blends combine different antioxidant mechanisms to provide broader protection during both processing and long-term service.

Blended antioxidant systems can be designed to provide:

• Processing stability
• Long-term thermal stability
• Oxidation resistance
• Improved color stability
• Better protection during repeated processing

Applications of Antioxidants

Antioxidants for Plastics

Antioxidants are widely used in plastic manufacturing to protect polymers from degradation during extrusion, injection molding, blow molding, compounding, and other high-temperature processing operations.

They can be used in:

• Polyethylene (PE)
• Polypropylene (PP)
• ABS
• Polystyrene (PS)
• Engineering plastics
• Thermoplastic elastomers
• Recycled plastics
• Other polymer systems

Antioxidants can help reduce discoloration, molecular weight loss, embrittlement, and loss of mechanical properties caused by oxidation.

Antioxidants for Rubber

Rubber antioxidants are important additives in the rubber and tire industry. They help protect rubber compounds against oxidative and thermal degradation during processing and service.

Applications include:

• Automobile tires
• Industrial rubber products
• Rubber belts
• Rubber hoses
• Rubber seals
• Footwear
• Mechanical rubber products

For rubber formulations, the appropriate antioxidant depends on the rubber type, processing conditions, required aging resistance, and formulation requirements.

Antioxidants for Polyolefins

Polyolefin materials such as PE and PP are susceptible to oxidative degradation, particularly during high-temperature processing.

Antioxidant systems can help protect polyolefins during:

• Polymerization
• Compounding
• Extrusion
• Injection molding
• Recycling
• Long-term use

A combination of primary and secondary antioxidants is often selected to provide balanced processing and long-term stabilization.

Antioxidants for Adhesives and Sealants

Antioxidants can be incorporated into adhesive and sealant formulations to improve resistance to thermal and oxidative degradation.

Applications include:

• Hot-melt adhesives
• Construction adhesives
• Industrial adhesives
• Polymer sealants
• Specialty adhesive systems

Antioxidants for Coatings

In selected coating formulations, antioxidants can help protect organic components from oxidative degradation and improve formulation stability.

Potential applications include:

• Industrial coatings
• Polymer coatings
• Protective coatings
• Specialty coatings
• Resin-based formulations

How Do Antioxidants Work?

Oxidation of polymers generally involves a free-radical chain reaction. Heat, oxygen, UV exposure, mechanical stress, and processing conditions can accelerate this process.

Antioxidants help interrupt or control the oxidation process through different mechanisms.

A simplified oxidation process can be represented as:

Polymer → Free Radicals → Hydroperoxides → Polymer Degradation

Antioxidants can help by:

Free-Radical Scavenging:
Primary antioxidants react with free radicals and interrupt oxidation chain reactions.

Hydroperoxide Decomposition:
Secondary antioxidants help decompose hydroperoxides into more stable products, reducing further oxidation.

Using appropriate antioxidant combinations can provide protection during both polymer processing and long-term service.

Benefits of Antioxidants

Depending on the formulation and application, antioxidants can provide:

• Improved thermal stability
• Improved oxidation resistance
• Better processing stability
• Reduced discoloration
• Reduced polymer degradation
• Improved retention of mechanical properties
• Longer material service life
• Better resistance to thermal aging
• Improved formulation stability

The actual performance depends on the antioxidant chemistry, dosage, polymer type, processing conditions, and other additives present in the formulation.

Common Antioxidant Products

Different antioxidant products are selected according to the polymer and application.

Specific products should be selected based on the required chemical structure, CAS number, polymer system, and application.

Technical Specifications

Technical specifications vary according to the specific antioxidant product.

Packaging and Storage

Antioxidants should generally be stored in sealed original packaging in a cool, dry, and well-ventilated area.

Protect the product from excessive heat, moisture, direct sunlight, and contamination. Specific storage conditions should follow the manufacturer’s product specification and SDS.

Common packaging options include:

• 20 kg bags
• 25 kg bags
• 25 kg cartons
• 200 kg drums
• Customized packaging

Antioxidant Supplier

We supply a range of Antioxidants for plastics, polymers, rubber, tires, adhesives, coatings, and other industrial applications.

Different antioxidant chemistries and grades can be provided according to customer requirements, including products designed for processing stability, thermal aging resistance, oxidation resistance, and long-term polymer protection.

We can provide:

• Product specifications
• Certificate of Analysis (COA)
• Safety Data Sheet (SDS)
• Product samples
• Technical documentation
• Customized specifications
• Customized packaging
• Bulk supply
• Export documentation

For product selection, customers are encouraged to provide the polymer or rubber type, application, processing temperature, required antioxidant function, dosage range, and quantity.

Frequently Asked Questions

What are Antioxidants?

Antioxidants are additives used to slow or prevent oxidative degradation in polymers, plastics, rubber, and other materials.

What are Antioxidants used for?

They are widely used in plastics, rubber, tires, adhesives, coatings, polymers, and other materials to improve resistance to oxidation and thermal degradation.

What is the difference between primary and secondary antioxidants?

Primary antioxidants mainly scavenge free radicals, while secondary antioxidants help decompose hydroperoxides. They are often used together to provide more comprehensive polymer stabilization.

Why are Antioxidants used in plastics?

Antioxidants help protect plastics from oxidation during high-temperature processing and long-term use. They can help maintain color, mechanical properties, and material stability.

Why are Antioxidants used in rubber?

Rubber antioxidants help reduce oxidative and thermal degradation and can improve the aging resistance and service life of rubber products.

Can Antioxidants be customized?

Yes. Different antioxidant products and combinations can be selected according to polymer type, processing conditions, required performance, and application requirements.

Request an Antioxidant Quote

Looking for a reliable Antioxidant supplier or manufacturer?

Contact us for antioxidant specifications, COA, SDS, samples, pricing, packaging, and bulk supply options.

Product: Antioxidants
Types: Primary / Secondary / Antioxidant Blends
Applications: Plastics / Rubber / Tires / Polymers / Adhesives / Coatings

Please provide your required antioxidant type or CAS number, polymer/rubber system, application, quantity, packaging requirements, and destination, and we can recommend a suitable product and provide a quotation.