Peroxide Cure vs. Sulfur

Attribute	Peroxide Cure	Sulfur
Curing Agent	Peroxide	Sulfur
Curing Process	Chemical reaction with peroxide	Chemical reaction with sulfur
Curing Temperature	Higher temperature required	Lower temperature required
Curing Time	Shorter curing time	Longer curing time
Strength	Higher strength	Lower strength
Elasticity	Lower elasticity	Higher elasticity
Cost	Higher cost	Lower cost

Introduction

When it comes to curing rubber, two commonly used methods are peroxide cure and sulfur cure. Both methods have their own unique attributes and advantages, making them suitable for different applications. In this article, we will explore the characteristics of peroxide cure and sulfur cure, highlighting their differences and benefits.

Peroxide Cure

Peroxide cure, also known as vulcanization with peroxides, is a widely used method for curing rubber. It involves the use of organic peroxides as curing agents. These peroxides decompose at elevated temperatures, releasing free radicals that initiate cross-linking reactions in the rubber compound.

One of the key advantages of peroxide cure is its ability to provide excellent heat resistance. The resulting cross-linked rubber exhibits improved thermal stability, making it suitable for applications that involve high temperatures. Additionally, peroxide cure offers good resistance to chemicals, oils, and solvents, enhancing the durability and longevity of the cured rubber.

Another notable attribute of peroxide cure is its ability to provide better compression set resistance compared to sulfur cure. Compression set refers to the ability of a rubber material to recover its original shape after being subjected to compression. With peroxide cure, the cured rubber exhibits lower compression set, making it ideal for applications where maintaining dimensional stability is crucial.

Peroxide cure also allows for faster curing times compared to sulfur cure. The decomposition of peroxides occurs at relatively lower temperatures, enabling efficient curing processes. This attribute is particularly advantageous in industries where quick production cycles are required.

However, it is important to note that peroxide cure may have limitations in terms of color stability. Some peroxides can cause discoloration in certain rubber compounds, which may be undesirable in applications where aesthetics are important. Additionally, peroxide cure can be more expensive compared to sulfur cure due to the cost of peroxide curing agents.

Sulfur Cure

Sulfur cure, also known as vulcanization with sulfur, is the traditional method for curing rubber. It involves the use of sulfur as the primary curing agent, along with accelerators and activators to facilitate the cross-linking process. Sulfur cure is widely used in various industries and has been the standard method for many years.

One of the key advantages of sulfur cure is its cost-effectiveness. Sulfur is readily available and relatively inexpensive, making it a preferred choice for applications where cost plays a significant role. Additionally, sulfur cure offers good aging resistance, ensuring that the cured rubber maintains its properties over an extended period.

Sulfur cure also provides excellent dynamic properties, such as high resilience and good flex fatigue resistance. These attributes make sulfur-cured rubber suitable for applications that involve repeated mechanical stress, such as tires and conveyor belts.

Another notable attribute of sulfur cure is its ability to provide good adhesion to various substrates. The cross-linking process facilitated by sulfur allows the rubber to bond effectively with different materials, enhancing the overall performance and reliability of the cured rubber.

However, sulfur cure may have limitations in terms of heat resistance compared to peroxide cure. The resulting cross-linked rubber may not exhibit the same level of thermal stability, making it less suitable for applications that involve high temperatures. Additionally, sulfur cure may have limitations in terms of resistance to certain chemicals and oils.

Conclusion

In conclusion, both peroxide cure and sulfur cure offer unique attributes and advantages in the rubber curing process. Peroxide cure provides excellent heat resistance, chemical resistance, and compression set resistance, making it suitable for applications that require dimensional stability and durability in high-temperature environments. On the other hand, sulfur cure offers cost-effectiveness, good aging resistance, dynamic properties, and adhesion to various substrates, making it a preferred choice for applications that involve repeated mechanical stress and where cost plays a significant role.

Ultimately, the choice between peroxide cure and sulfur cure depends on the specific requirements of the application, including temperature range, chemical exposure, mechanical stress, and cost considerations. By understanding the attributes and benefits of each method, manufacturers can make informed decisions to ensure the optimal performance and longevity of their rubber products.