DuPont™ Tefzel® is a modified ETFE (ethylene-tetrafluoroethylene) fluoroplastic available as pellets or as powder for rotational molding. Tefzel® ETFE resin combines superior mechanical toughness with an outstanding chemical inertness that approaches that of Teflon® fluoroplastic resins. Tefzel® features easy processibility, a specific gravity of 1.7, and high-energy radiation resistance. Most grades are rated for continuous exposure at 150°C (302°F), based on the 20,000-hr criterion.
Tefzel® ETFE fluoroplastic resins are processed by conventional melt-extrusion techniques and by injection, compression, transfer, rotational, and blow molding processes. The relatively high flow rate of these ETFE resins provides higher rates with less draw-down, as compared to those required for Teflon® FEP and PFA. Reciprocating screw injection molding machines are preferred. Long extruder barrels, relative to diameter, should be used to provide residence time for melting these high-temperature resins.