In 1937, before the Second World War, the company DU PONT (USA) succeeded in forming the organic fluorinated compound polytetrafluoroethylene (PTFE) with the structural formula of n(F2C = CF2). The atoms of carbon (C) in the PTFE molecule are completely covered with atoms of fluorine (F), while the bond between the carbon and fluorine (C-F) represents one of the strongest bonds in organic chemistry. Consequence – universal resistance to almost all chemical influences.