Polytetrafluoroethylene chemical reactivity

Fluorine is a reactive, almost colorless gas of F2 molecules. Most of the fluorine produced by industry is used to make the volatile solid UF6 used for processing nuclear fuel (Section 17.12). Much of the rest is used in the production of SF6 for electrical equipment and to make fluorinated carbon compounds, such as Teflon (polytetrafluoroethylene). Most fluoro-substituted hydrocarbons are relatively inert chemically they are inert to oxidation by air, hot nitric acid, concentrated sulfuric acid, and other strong oxidizing agents. 

Fluorine substitution on carbon confers particular reactivity because of its particular properties Fluorine as the most electronegative element forms very strong CF bonds which are sized to "cover" perfluorocarbons tightly. Polytetrafluoroethylene (Teflon) is one practical example illustrating the exceptional chemical and thermal stability of saturated perfluorocarbons in a sharp contrast to explosive tetrafluoroethylene or to fluoroacetylenes. 

Polymeric membranes are monolithic, continuously porous materials. Membranes can be produced from numerous organic polymers including polyalkanes (polyethylene and polypropylene) and their fluorinated derivatives [polyvinylidene fluoride and polytetrafluoroethylene (PTFE)]. Once formed, a membrane can be chemically functionalized by a number of methods including direct conversion of functional groups in the bulk polymer, coating of the surface with a preformed polymer, or graft copolymerization of reactive monomers onto the membrane surface. 

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