25067-11-2

The fluorinated ethylene propylene (Perfluoroethylene propylene copolymer; FEP) macromolecule consist mainly of a linear chain with the basic monomer unit [—(CF2 )3 —CF(CF3 )—]n.This translucent fluorocarbon is flexible and more workable than PTFE, and like PTFE it resists to all known chemicals except molten alkali metals, elemental fluorine, fluorine precursors, and concentrated perchloric acid. It withstands temperatures up to 200°C and may be sterilized by all known chemical and thermal methods. Certain carefully prepared films of FEP can be used as windows in equipment when necessary. The product has found extensive use as a pipe fitting liner as well as a liner in small vessels.

Similar to polytetrafluoroethylene but has a higher coefficient of friction.

The elastomer is prepared by high-pressure, free-radical aqueous emulsion polymerization. Fluorine is substituted for hydrogen. The initiators are organic or inorganic peroxy compounds, such as ammonium persulfate, and the emulsifying agent is usually a fluorinated acid soap. Applications include tubing, hose, and gaskets.