PTFE (Polytetrafluoroethylene, Teflon®)
PTFE is the most chemically inert of the sealing materials – it is a tough polymer possessing an incredible working temperature range.
PTFE is resistant to most chemicals including acids, bases, oils, and steam. PTFE is a very tough material, offering outstanding tear resistance and abrasion resistance. This material’s slippery surface properties make it advantageous for sealing in moving systems such as mass spectrometer probes and valves.
It is worth noting that this material is not easily compressed, and therefore may not seal as easily as some of the other polymers.
Common fillers for PTFE materials are glass fibre, carbon graphite and molybdenum disulphide.
Special care is to be taken during installation of PTFE seals.