Study on mechanical properties of PTFE-modified sealing gaskets for alkaline electrolyzers

The Alkaline Water Electrolysis (AWE) technology stands as the preeminent and most industrialized approach within the realm of electrolytic hydrogen production methodologies. The electrolyzer, as the cornerstone of this system, necessitates impeccable sealing performance to ensure seamless and dependable operation. The efficacy of the electrolyzer’s sealing is inherently tied to the gasket, where the mechanical properties of the gasket material serve as the cornerstone for guaranteeing sealing stability. This paper delves into an exhaustive investigation of the mechanical behavior exhibited by commercially available, modified Polytetrafluoroethylene (PTFE) sealing gaskets employed in AWE electrolyzers. A comprehensive suite of experiments, including tensile and compression tests, along with compression recovery assessments, has been conducted. This is to meticulously analyze the influence of temperature and stress on the mechanical properties of these gaskets. The results from the tensile tests reveal that an elevation in temperature leads to a decrement in the elastic modulus of the material, with the peak elongation at break observed at 95°C, signifying an optimal thermodynamic condition. In the compression tests, as the temperature escalates, the elastic modulus of the material undergoes a gradual decline, while its plastic deformation capacity intensifies. This enables the sample to withstand heightened stress post-yielding without experiencing fracture. Furthermore, the compression recovery experiments underscore the profound impact of both temperature and stress on the compression recovery performance of the sealing gaskets. An increase in temperature exacerbates plastic deformation within the material, which is subsequently mirrored by a decline in the recovery rate. Additionally, when stress levels are heightened, the recovery performance of the gasket under high-temperature conditions experiences a rapid deterioration. Hence, in practical applications, it is imperative to exercise meticulous control over temperature and stress parameters to ensure the stability and reliability of gasket performance. The insights garnered from this research offer invaluable guidance for the design of electrolyzer sealing mechanisms and the ongoing development of sealing gasket materials.