TETRAFLUOROETHYLENE-PERFLUOROVINYL ETHER COPOLYMERS

Peifluoioalkoxy (PFA) fluoiocaibon lesins aie designed to meet industry s needs in chemical, electrical, and mechanical appHcations. These melt processible copolymers contain a fluorocarbon backbone in the main chain and randomly distributed perfluorinated ether side chains  

A combination of excellent chemical and mechanical properties at elevated temperatures results in rehable, high performance service to the chemical processing and related industries. Chemical inertness, heat resistance, toughness and flexibiUty, stress-crack resistance, excellent flex life, antistick characteristics, Htfle moisture absorption, nonflammability, and exceptional dielectric properties are among the characteristics of these resins. 

The introduction of a perfluoromethyl side chain (Teflon FEP) greatly reduces the crystallinity of PTFE. Crystallinity is reduced even further by replacing the short side chain with a long side chain, such as perfluoropropyl ether. In contrast to Teflon EEP, only a small amount of vinyl ether is requited to reduce crystallinity and develop adequate toughness. 

Tetrafluoroethylene [116-14-3] and perfluorovinyl ether are copolymerized in aqueous (1,2) or nonaqueous (3) media. The polymer is separated and converted into various forms, such as extmded cubes, powders, beads, or dispersions. This family of products is manufactured by Du Pont, Daikin, and Hoechst and sold under the trade names of Teflon PEA, Neoflon AP, and Hostaflon TEA, respectively. 

Preparation. The preparation of tetrafluoroethylene has been described previously. Perfluorovinyl ethers (4—7) are prepared by the following steps. Hexafluoropropylene [116-15-4] (HEP) is oxidized to an epoxide HEPO [428-59-1] (5) which, on reaction with perfluorinated acyl fluorides, gives an alkoxyacyl fluoride. 

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Perfluorinated ethylene—propylene copolymers, Tetrafluoroethylene—ethylene copolymers, Tetrafluoroethylene—perfluorovinyl ether copolymers, Poly(vinyl fluoride),... 

Hostaflon TFA - [FLUORINECOMPOUNDS,ORGANIC - TETRAFLUOROETHYLENE-PERFLUOROVINYL ETHER COPOLYMERS] (Vol 11)... 

D. Fluorocarbon Polymers. Four different fluorocarbons account for the bulk of the laboratory applications polytetrafluoroethylene, Teflon PTFE po-ly(chlorotrifluoroethylene), KEL-F tetrafluoroethylene-hexafluoropropylene copolymer, Teflon FEP and tetrafluoroethylene-perfluorovinyl ether copolymer, PFA. These polymers are inert with most chemicals and solvents at room temperature and exceptionally inert with oxidizing agents. They also have an exceptional resistance to temperature extremes. However, they are decomposed by liquid alkali metals, solutions of these metals in liquid ammonia, and carban-ion reagents such as butyllithium. Teflon retains some of its compliance at liquid hydrogen temperature. The maximum temperature which is recommended for continuous service is 260°C for Teflon PTFE and PFA, and about 200°C for Kel-F and Teflon FEP. 

Gangal, S.V. Tetrafluoroethylene-perfluorovinyl ether copolymer. In Kirk-Othmer Encyclopedia of Chemical Technology, 4th Ed. John Wiley Sons New York, 1994 Vol. 11, 671-683. 

Hegazy, E.S.A., El-Assy, N.B., Rabie, A.G.M. et al. 1984. Kinetic study of preirradiation grafting of acrylic acid onto poly(tetrafluoroethylene-perfluorovinyl ether) copolymer. J Polym Sci Polym Chem. 22 597-604. 

PERFLUORINATED POLYMERS, TETRAFLUOROETHYLENE-PERFLUOROVINYL ETHER COPOLYMERS... 

Gangal, S. V. Brothers, P. D. Perfluorinated Polymers, Tetrafluoroethylene-Perfluorovinyl Ether Copolymers. In Encyclopedia of Polymer Science and Technology, 4th Edition, John Wiley Sons, Hoboken, NY, 2014 Vol. 9, pp. 547-559. 

Gangal SV, Brothers PD. Perfluorinated polymers, tetrafluoroethylene-perfluorovinyl ether copolymers. Encyclopedia of polymer science and technology. Online ed. John Wiley and Sons 2010. 

Gangal SV. Tetrafluoroethylene-perfluorovinyl ether copolymer. 4th ed. Kirk-Othmer encyclopedia of chemical technology, 11. New York John Wiley and Sons 2004. p. 671-83. 

Gangal, S. V., Tetrafluoroethylene-Perfluorovinyl ether Copolymer in Kirk-Othmer Encyclopedia of Chemical Technology, 4 ed., 11 671-683, John Wiley Sons, New York, 1994. 

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