3M White Paper: Long-Term Compression Stress Relaxation of Elastomers in OAT Coolants
November 2, 2021
3M is sharing a white paper that compares the long-term compression stress relaxation (CSR) of hydrocarbon rubbers to FKM, a category of materials that include 3M™ Dyneon™ fluoroelastomers. All these materials were immersed in organic acid technology (OAT) coolant and in ethylene glycol coolant for 3000 hours. Traditionally, FKM fluoroelastomers have not been used with coolants, but higher-temperature conditions and changing coolant chemistries are raising the demand for new sealing materials.
As the white paper explains, immersion in the OAT coolant affected all the materials more than immersion in ethylene glycol. With the OAT coolant, most of the polymers retained a sealing force of around 20%. However, 3M™ Dyneon™ Fluoroelastomer FPO 3820 showed exceptional resistance and retained 57% sealing force after long-term CSR testing at elevated temperature. Consequently, this high fluorine material is an ideal candidate for higher-temperature coolant applications.
This 3M white paper is accessible from a new automotive-focused web page, 3M.com/FKMauto, that contains several other resources. You can also access this white paper by following this link (registration is required):