Carbon black/ethylene propylene diene monomer (EPDM) rubber as polymer electrolyte membrane fuel cell gaskets: mechanical and chemical assessment

• Published in: Iranian polymer journal 2024-02, Vol.33 (2), p.169-183
• Main Authors: Shamsabadi, Amirsaeed, Farahani, Ali, Shirkavand, Mohammad Mahdi, Hafezi, Mohammad-Javad, Tohidian, Mahdi
• Format: Article
• Language: English
• Subjects: Accelerated tests; Carbon; Carbon black; Ceramics; Chain scission; Chemistry; Chemistry and Materials Science; Composites; Compressive strength; Crosslinking; Elastomers; Electrolytes; Electrolytic cells; Ethylene; Fuel cells; Gaskets; Glass; Hardness; Mechanical properties; Monomers; Natural Materials; Original Research; Polymer Sciences; Propylene; Proton exchange membrane fuel cells; Sealing materials; Tensile properties; Tensile strength
• ISSN: 1026-1265; 1735-5265
• DOI: 10.1007/s13726-023-01239-9

In proton electrolyte membrane fuel cells (PEMFCs), elastomeric gaskets are utilized to separate the reactant gases from each other and hamper the leakage of gases/liquids from the specified perimeter. To ensure long-term performance of gaskets, it is necessary to design and manufacture high-performance, long-lasting sealing materials. In this study, PEMFC gaskets with high hardness and low compression set values were designed by incorporation of different carbon black (CB) contents in ethylene propylene diene monomer (EPDM). The fuel cell environment was simulated by an accelerated durability test (ADT) method, and the mechanical and chemical characteristics of the gasket such as hardness, tensile properties, compression set, crosslink density, and weight change were examined before and after 400 and 800 h of exposure to an acidic solution. As a result of the incorporation of CB, the gaskets’ mechanical properties were significantly enhanced, with a hardness increase from 51 to 72 and tensile strength rise from 2.51 to 34.8 MPa after increasing the CB content from 0 to 60 phr. Despite that, incorporating CB has also caused a negative effect on gaskets’ properties by increasing the compression set value from 2.75 to 9%. The gasket containing 20 phr carbon black content possessed more balanced mechanical properties and performance than the other gaskets (hardness of 63, a compression set of 2.95%, and a tensile strength of 11.3 MPa). In addition, the aging test results revealed that the aging process has altered the mechanical properties of gaskets due to the chain scission and crosslinking/de-crosslinking of rubbers. Graphical abstract