PTFE is obtained by polymerizing tetrafluoroethylene ( CF2 = CF2 ). Polytetrafluoroethylene is one of the most resistant plastic thermally and chemically. The advantages of this material is, inter alia, a low coefficient of friction, relatively small defects in resistance to abrasion and deformation of the material after prolonged exposure to loads.

PTFE can be used in a temperature range from -200 to +260°C. Resistance to such a low temperature allows the use of a polymer to seal liquid gases.

The chemical resistance of PTFE:

In terms of chemical resistance PTFE is superior than all known materials, is non-flammable and insoluble in all known solvents, it does not absorb water, it isn't resistant only to molten alkali metals such as sodium, potassium, fluorine gas and hydrogen fluoride HF. At temperatures above 400°C decomposes with the release of toxic gases. To improve the mechanical properties and abrasion resistance primarily PTFE is used with fillers which include:

• glass fiber
• brown
• graphite or carbon powder
• molybdenum disulfide
• steel