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Polytetrafluoroethylene (PTFE) is a partially crystalline substance obtained from the monomer tetrafluoroethylene (TFE) by polymerization. The macro-molecules created in this process have a linear structure.
PTFE’s chain structure has two interesting
characteristics:
 PTFE
The carbon chain is almost completely shielded by fluorine atoms, thus being protected from external influences. The carbon-fluorine combination is one of the strongest bondings in organic chemistry (dissociation energy: 460 KJ/mol). This gives PTFE its exceptionally high chemical and thermal resistance.
 Modified PTFE
Modified PTFE is obtained from the monomer, tetrafluoroethylene (TFE) and a modifier (which is perfluorinated as well), perfluoropropylvinylether
(PPVE). The shorter molecular chains (compared to PTFE) have a higher tendency to crystallize. This
would degrade the mechanical properties of the material. The modifier effectively inhibits crystallization. This means that with modified PTFE it is possible to combine thermoplastic property components – due to the shorter molecular chains – with the good mechanical properties
of standard PTFE.
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