ETFE Ethylene Tetrafluoroethylene Copolymers

This copolymer has proved particularly suitable for wire and cable insulation, with many grades being rated at 155°C for 20 000 h continuous exposure. It is extensively used in electrical systems for aircraft, underground railways, computers, telecommunications installations and heating circuits. Because of its toughness combined with its heat and chemical resistance it also finds use for lining pumps and valves and other equipment for the chemical industry and for laboratory ware. 

Whereas Tefzel is said to be an internally stablised copolymer of TFE and ethylene, other copolymers that are compounds of similar copolymers with stabilisers of antioxidants are now also available (Hostaflon ET by Hoechst and Aflon by Asahi Glass Co.). Glass-fibre-filled grades are also available. 

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V Fluoroplastics (ECTFE ethylene-chlorotrifluoro-ethylene copolymer ETFE ethylene-tetrafluoroethylene copolymer FEP fluorinated ethylene-propylene copolymer)... 

Copolymeis of ethylene [74-85-1] and tetiafluoioethylene [116-14-3] (ETFE) have been alaboiatory curiosity for more than 40 years. These polymers were studied in connection with a search for a melt-fabricable PTFE resin (1 5) interest in them fell with the discovery of TFE—HFP (FEP) copolymers (6). In the 1960s, however, it became evident that a melt-fabricable fluorocarbon resin was needed with higher strength and stiffness than those of PTFE resins. Earlier studies indicated that TFE—ethylene copolymers [11939-51 -6] might have the right combination of properties. Subsequent research efforts (7) led to the introduction of modified ethylene—tetrafluoroethylene polymer [25038-71-5] (Tefzel) by E. I. du Pont de Nemours Co., Inc, in 1970. 

Abbreviations for plastics ABS, acrylonitrile-butadiene-styrene CPVC, chlorinated poly vinyl chloride ECTFE, ethylene-chlorotrifluoroethylene ETFE, ethylene-tetrafluoroethylene PB, polybutylene PE, polyethylene PEEK, poly ether ether ketone PFA, perfluoroalkoxy copolymer POP, poly phenylene oxide PP, polypropylene PVC, polyvinyl chloride PVDC, poly vinylidene chloride PVDF, poly vinylidene fluoride. 

Screening tests were conducted on potential construction materials. The candidate materials evaluated included the following polytetrafluoroethylene (PTFE, TFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy-alkanes (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), ethylene-chlorotrifluoroethylene copolymer (E-CTFE), poly vinylidene fluoride (PVDF), polypropylene (PP), and polyvinyl chloride (PVC). These materials were chosen based on cost, availability, and information from manufacturers on compatibility with acid solutions. 

Polyvinylidene fluoride (PVDF) and Ethylene tetrafluoroethylene copolymer (ETFE) can be considered as diluted PTFE s, which in their structure and their properties... 

Tefzel ETFE (ethylenetetrafluoroethylene). This plastic is white, translucent, and slightly flexible. It is a close analog of the Teflon fluorocarbons, an ethylene tetrafluoroethylene copolymer. ETFE shares the remarkable chemical and temperature resistance of Teflon TFE and FEP and has even greater mechanical strength and impact resistance. 

Note ETFE, copolymer of ethylene and tetrafluoroethylene ECTFE, copolymer of ethylene chlorotrif- ... 

Note ETFE, copolymer of ethylene and tetrafluoroethylene MFA, copolymer of perfluoromethylvi-nylether and tetrafluorethylene PFA, copolymer of perfluoropropylvinylether and tetrafluoroethylene FEP, fluorinated ethylene-propylene copolymer PCTFE, poly(chlorotrifluoroethylene) PVDF, poly(vinylidene fluoride) VDF-HFP, copolymer of vinylidene fluoride and hexafluoropropylene. 

Copolymers of tetrafluoroethylene were developed in attempts to provide materials with the general properties of PTFE and the melt process-ability of the more conventional thermoplastics. Two such copolymers are tetrafluoroethylene-hexafluoropropylene (TFE-HFP) copolymers (Teflon FEP resins by Du Pont FEP stands for fluorinated ethylene propylene) with a melting point of 290°C and tetrafluoroethylene-ethylene (ETFE) copolymers (Tefzel by Du Pont) with a melting point of 270°C. These products are melt processable. A number of other fluorine containing melt processable polymers have been introduced. 

Material Family ETHYLENE TETRAFLUOROETHYLENE COPOLYMER (ETFE) ... 

Alternating ethylene-tetrafluoroethylene copolymer (ETFE) having a 50/50 comonomer composition crystallizes in two polymorphic forms. An orthorhombic form, stable at room temperature, and a disordered hexagonal form, stable at high temperatures. The crystal structures of both forms have been studied and the structural disorder present in both forms have been analyzed as a function of the composition [250-256]. 

An increase in the high temperature (200 °C) tensile properties of the ethylene-tetrafluoroethylene copolymer, ETFE, after irradiation in nitrogen at room temperature followed by heat treatment at 162 °C in nitrogen for 20 min indicates some crosslinking [118]. On the other hand, irradiatimi carried out in air showed very little cross-linking [119]. ETFE behaves in some ways similar to poly-vinyUdene fluoride (PVDFO in that there is competition between crosslinking and scissimi. Some of the tensile properties, measured at 200 °C, of irradiated ETFE are shown in Table 52.14 [119]. 

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