ECTFE (ethylenechlorotrifluoroethylene) is a copolymer of ethylene and chlorotrifluoroethylene. It is a semi-crystalline fluoropolymer (a partially fluorinated polymer) designed to provide chemical resistance in heavy-duty corrosion applications. Physical and chemical properties ECTFE is resistant to acids at high concentrations and temperatures, caustic media, oxidizing agents and many solvents. It has similar chemical resistance to PTFE. A chemical resistance table, based on immersion tests, has explored this further. Permeation of large molecules is slow in fluoropolymers and thus is not relevant in the final application. Small molecules, however, may permeate through the polymer matrix at a relevant time. In lining or coating applications, the permeation of certain small molecules determines the lifetime of anti-corrosion protection. H2O, O2, Cl2, H2S, HCl, HF, HBr, N2, H2, CH3OH, etc. are relatively mobile in a polymer matrix and lead to measurable effects. Permeation resistance is significant for lining and coating applications, because permeating species may attack underlying mechanical layers, such as fiber reinforced plastic or steel. This high permeation resistance to small molecules is a consequence of the free volume occupied by the chlorine atom in the polymer chain. ECTFE has a continuous usage temperature range between typically –76 °C and +150 °C (–105F to +300F). It has good impact resistance and Young's modulus in the range of 1700 MPa, allowing for self-standing items and pressure piping systems. ECTFE maintains high impact strength in cryogenic applications. In terms of fire resistance, ECTFE shows a limiting oxygen index of 52%. This is between the fully fluorinated polymers PTFE, PFA and FEP with a limiting oxygen index of 95% and other partially fluorinated polymers like PVDF with a limiting oxygen index of 44% and ETFE with a limiting oxygen index of 30%. ECTFE is an electrical insulator, with high resistivity and a low dielectric constant as well as a low dissipation factor, allowing its use for wire and cable primary and secondary jacketing. Similar to other fluoropolymers, ECTFE has good UV resistance, in particular against UV-A and UV-B. ECTFE films can be transparent. ECTFE is welded in a variety of methods, including: Butt welding Infrared welding High frequency welding Hot gas welding Ultrasonic welding Applications ECTFE is applied in several ways: By electrostatic powder coating on metal surfaces By rotolining on metal surfaces rotolining grade Halar 6012F By sheet lining on metal surface or on fiber reinforced plastic FRP (glass fiber, carbon fiber, ...). By extrusion or