PTFE silicone bonded caps are used in chromatography applications. They seal sample vials while allowing easy and reliable access by an autosampler needle.
These septa are composed of a two-layer structure: an outer layer of polytetrafluoroethylene (PTFE) and an inner core of silicone. This combination provides an ideal balance of chemical resistance, flexibility, and sealing capability.
The PTFE layer offers exceptional resistance to chemicals, protecting the septum from degradation caused by exposure to organic solvents, acids, and bases. It also prevents contamination, ensuring the sample’s purity and the integrity of analytical results.
The silicone core provides elasticity and durability, enabling easy needle penetration without damaging the septum or causing needle bending. Additionally, the silicone allows for effective resealing after multiple injections, maintaining a secure seal to prevent evaporation or contamination.
These septa are widely used in gas chromatography (GC), liquid chromatography (LC), and headspace sampling, where chemical compatibility and leak prevention are crucial. They are ideal for high-throughput environments such as pharmaceutical quality control, environmental analysis, and food testing.
