Both sulphur-cured and peroxide-cured EPDM rubber have their own advantages and are suitable for different applications. However, there are a few reasons why sulphur-cured EPDM rubber is often considered better than peroxide-cured EPDM rubber in certain contexts:
- Cost: Sulphur-cured EPDM rubber is generally less expensive than peroxide-cured EPDM rubber. The cost-effectiveness of sulphur curing can make it a more attractive option for applications where cost is a significant factor.
- Processing and Curing Time: Sulphur-cured EPDM rubber has a shorter curing time compared to peroxide-cured EPDM rubber. This means that the manufacturing process for sulphur-cured rubber is typically faster, leading to increased production efficiency.
- Compression Set Resistance: Sulphur-cured EPDM rubber exhibits better compression set resistance than peroxide-cured EPDM rubber. Compression set refers to the ability of a rubber material to retain its shape and elasticity after being subjected to compressive forces over an extended period. Sulphur curing helps improve the compression set resistance of EPDM rubber, making it more suitable for applications where long-term resilience is required.
- Heat Aging Resistance: Sulphur-cured EPDM rubber generally demonstrates better resistance to heat aging compared to peroxide-cured EPDM rubber. Heat aging refers to the deterioration of rubber properties due to prolonged exposure to high temperatures. Sulphur curing enhances the ability of EPDM rubber to withstand heat aging, making it suitable for applications where elevated temperatures may be present.
- Odor: Sulphur-cured EPDM rubber typically has a milder odor compared to peroxide-cured EPDM rubber. This characteristic can be important for applications where odor could be an issue. Depending on the location: indoor vs outdoor, areas with less air movement (ie. sheltered areas), or large gathering areas such as a playground, a sulfur-cured EPDM rubber would likely be preferable.
It’s worth noting that the specific requirements of a given application, such as the desired physical properties, chemical resistance, or environmental conditions, should be taken into consideration when choosing between sulphur-cured and peroxide-cured EPDM rubber.