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FEP Similar properties are displayed by FEP:(Fluorinated ethylene propylene) [CF(CF3)-CF2(CF2-CF2) n]m The molecular weight of this copolymer is 50,000 to 500,000 and the crystallinity is about 50%. The maximum service temperature of 205oC is lower than PTFE. FEP is thermoplastically moldable (injection molded at temperatures of 320o - 360oC extruded at 350o - 410oC) is translucent, flexible and feels heavy because of its high density . FEP has the greatest clarity of the three types of TEFLON® . TEFLON® FEP is the Registered Trade Mark of E.I. Dupont, U.S.A. and we are the direct user of TEFLON® products from E.I. DuPont. PFA PFA (perfluoroalkoxy) has the same advantages as PTFE TEFLON® with the structure: [ CF(OR1)-CF2(CF2-CF2)n]m R represents CnF2n+1 PFA can be melt processed (extruded). The chemical resistance is comparable to PTFE. PFA is translucent and slightly flexible. It has greater mechanical strength than PTFE. Its melting temperature is 305oC and maximum operating temperature is 260oC. PFA was first used in the semiconductor industry for injection molded wafer carriers and similar articles that resisted aggressive chemicals and high temperature chemical processing . Now, PFA is also considered to be the best TEFLON® for semiconductor piping applications, and is accepted for both liquid reagent and UPDI water handling in advanced processing applications. TEFLON® PFA is the Registered Trade Mark of E.I. Dupont, U.S.A. and we are the direct user of TEFLON® products from E.I. DuPont.
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