Reducing Fluorinated Elastomer Use in High-Performance Turbocharger Hoses through Advanced FKM-Silicone Interface Technology

DRC – Doctors of Rubber Compounding

Fluoroelastomers (FKM) are widely used in high-performance turbocharger hoses because of their excellent resistance to high temperatures, oils, fuels, and aggressive chemicals. However, the use of FKM in an entire hose can result in the consumption of significantly more fluorinated material than is functionally required. In addition to its high material cost, reducing the use of fluorinated elastomers is becoming increasingly important from a sustainability perspective, especially on reducing the potential environmental impact associated with PFAs-containing materials.

A key challenge in reducing FKM content is the inherently poor adhesion between FKM and silicone rubber. Although silicone provides promising thermal characteristics along with flexibility and so a good potential to replace with FKM in some parts of the hose, the weak interphase between these two elastomers has traditionally limited the development of reliable multilayer constructions. As a result, applications requiring the combined performance of these materials have often relied on using mostly FKM in the component.   

To address this challenge, DRC, in collaboration with a university research partner, has developed a novel FKM-silicone interfacial technology that enables the production of reliable multilayer turbocharger hoses. The development combined industrial application expertise with university-based research into elastomer compatibility, vulcanization mechanisms, and interfacial interactions. With the optimization of material formulations and processing conditions, a strong and stable interphase between FKM and silicone was achieved.  

The resulting technology changes the way FKM can be used within the hose. Rather than resulting in FKM as the primary material for the entire component, FKM can be strategically used only in areas where its exceptional fluid resistance and high-temperature properties are essential. Silicone can then be used in the remaining layers where its performance is sufficient. The 1right material in the right place” approach enables the development of multilayer turbocharger hoses with substantially reduced FKM content while maintaining the required functionality of the materials for a specific application.

From a sustainability perspective, the principal outcome is therefore material reduction at the component level. By replacing unnecessary volumes of FKM with silicone, the technology reduces the quantity of fluorinated elastomer required to manufacture each hose. This can reduce reliance on high-value fluorinated raw materials, improve material efficiency, and contribute to reducing the potential environmental impact associated with PFAs-related materials.