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|Section2= |Section6= |Section7= }} ECTFE (Ethylene ChloroTriFluoroEthylene) was designed to provide excellent chemical resistance in heavy duty corrosion applications. It is a partially fluorinated polymer (a fluoropolymer), semi-crystalline and can be processed in the melt. Chemically it is a copolymer of ethylene and chlorotrifluoroethylene. It is marketed under the brand name Halar ECTFE by Solvay Specialty Polymers,〔(【引用サイトリンク】title=Solvay Plastics )〕 a subsidiary of Solvay. ==Physical and chemical properties== Since its introduction in 1970, ECTFE has been used in many industries where excellent corrosion resistance is the key to success. It is resistant to acids even at high concentrations and temperatures, caustic media, oxidizing agents and many solvents. It is said to have similar chemical resistance to PTFE.〔(【引用サイトリンク】title=Halar ECTFE - Precision Fiber Engineering - Atkins & Pearce )〕 A chemical resistance table〔http://www.integument.com/Portals/34/Files/Chemical-Resistance/ectfe.pdf〕 based on immersion tests is available. Moreover, ECTFE has for many permeating species the best permeation resistance of all fluoropolymers. Permeation of large molecules is usually rather slow in fluoropolymers and thus not relevant in the final application. Small molecules, however, may permeate through the polymer matrix in a relevant time. In lining or coating applications, the permeation of certain small molecules determine the lifetime of anticorrosion protection. H2O, O2, Cl2, H2S, HCl, HF, HBr, N2, H2, CH3OH, etc. are relatively mobile in a polymer matrix and lead to measurable effects.〔C.M. Hansen, Progr. Org. Coat., 42, 167 (2001)〕〔Polymer Handbook, J. Brandrup (Editor), E. H. Immergut (Editor), E. A. Grulke (Editor), Publication Date: May 29, 2003 ISBN 978-0471479369〕 In particular in lining and coating applications, the permeation resistance is the key to success as permeating species may attack the underlying mechanical layers, such as fiber reinforced plastic or steel. Various commercial data bases confirm the excellent permeation resistance of ECTFE. This high permeation resistance to small molecules is a consequence of the free volume occupied by the chlorine atom on the polymer chain. ECTFE has a wide continuous usage temperature range between typically –76 °C and +150 °C (–105F to +300F). It has good impact resistance and a Young's modulus in the range of 1700 MPa (see suppliers website)〔(【引用サイトリンク】title=Halar® ECTFE for Coatings )〕 allowing for self standing items and pressure piping systems. ECTFE offers high impact strength even in cryogenic applications. ECTFE shows good fire resistance with a limiting oxygen index of 52%.〔(technical datasheet of a typical ECTFE grade )〕 This is between the fully fluorinated polymers PTFE, PFA and FEP with an limiting oxygen index of 95% and other partially fluorinated polymer like PVDF with a limiting oxygen index of 44% and ETFE with an limiting oxygen index of 30%. ECTFE has good electrical insulator properties, i.e. 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 allowing its use for outdoor applications. ECTFE films〔(【引用サイトリンク】title=Ajedium™ Films )〕 can be transparent.〔(【引用サイトリンク】format=PDF )〕 Specialty ECTFE films Press release UV blocking Halar ECTFE film〔(【引用サイトリンク】title=Solvay Solexis launches new Halar® ECTFE Front sheet films for photovoltaic industry )〕 provide transparency and UV protection for underlying layers. Finally ECTFE can be welded in many ways : * Butt welding * Infrared welding * High frequency welding * Hot gas welding * Ultrasonic welding 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ECTFE」の詳細全文を読む スポンサード リンク
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