Perfluoroalkyl vinyl ether

A laser beam was used for graft polymerization of AAc onto a tetrafluo-roethylene-perfluoroalkyl vinyl ether copolymer film [81]. The film placed in contact with AAc solution was irradiated with KrF laser through the film to excite the film/solution interface. Surface composition of the grafted film determined by XPS revealed an extensive loss of fluorine atom and an increase of oxygen atom in addition to the presence of a Cls line shape, similar to that of AAc monomer. Mirzadeh et al. [82] used pulsed laser beam for the graft polymerization of AAm on a rubber surface in the presence of a photosensitizer, ben-zophenone, or AIBN. 

During their preparation of fluorinated ethers ArOCF2CHFRORf from the reactions of sodium phenoxides with perfluoroalkyl vinyl ethers, namely CF2=CFORf [Rf=C3F7, C3F7OCF(CF3)=CF2, and Me02CCF2CF20CF(CF3)=CF2], Feiring and Wonchoba117 found that brominated and chlorinated products were also formed when hexachloroethane and 1,2-dibromotetrafluoroethane, respectively, were present (equation 75). While they... 

Industrial Synthesis of Perfluoroalkyl Vinyl ether Monomers... 

PFA is a copolymer of TFE and a perfluoroalkyl vinyl ether, such as perfluoropropyl vinyl ether PPVE. Copolymerization of perfluoroalkylvinyl ethers with tetrafluoroethylene can be done in a halogenated sol-... 

FEP is a random copolymer of TFE and HFP, which can be polymerized, in an aqueous or a nonaqueous media. Terpolymers of this class contain other monomers, such as perfluoroalkyl vinyl ether (e.g., PPVE) to improve stress crack resistance. 

Figures 3.34 and 3.35 show the relationship of tensile strength and ultimate (break) elongation with temperature for perfluoroalkyl vinyl ether modified perfluoroalkoxy polymer (PFA). Figures 3.36 through 3.38 show a comparison of the properties of PFA with MFA, which is perfluoromethyl vinyl ether (PMVE). The common measurement technique for tensile properties of fiuoropiastics is ASTM D1708.

Tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, vinyl fluoride, vinylidene fluoride, perfluoroalkyl vinyl ether Free-radical-initiated chain polymerization Coatings for chemical process equipment, cable insulation, electrical components, nonsticking surfaces for cookware... 

For the gasket, instead of PP, poly(phenylene sulfide), poly(ethyl-ene terephthalate), poly(amide), liquid crystal polymer, tetrafluoroethyl-ene/perfluoroalkyl vinyl ether copolymer resin, PEEK, and poly(ether nitrile) have been found to be free of explosions and other drawbacks at the reflow temperature." ... 

Perfluoroalkyl vinyl ether copolymer resin, 227 Perfluorooctyl methacrylate, 74 PerlenetetracarboxyUc-bis-benzimidazole, 49 Perylene, 13, 49 Phenol, 141, 241, 257, 286 Phenolphthalein, 258, 263, 284, 286 Phenolsulfonic acid, 241 p-Phenoxybenzenesulfonyl chloride, 248 4-Phenoxybenzophenone, 213 p-Phenoxybenzoyl chloride, 210, 213, 248 Phenoxyethylacrylate, 540 4-(4-Phenoxyphenoxy)benzophenone, 213 p-Phenoxyphenoxybenzoyl chloride, 210, 213... 

The polymers based on PPVE are called PFA and the perfluoroalkyl vinyl ether group is typically added at 3.5% or less. When the comonomer is PMVE the polymer is called MFA. A structure of PFA is shown in Figure 9.82. The CAS number of PFA using PPVE as comonomer is 26655-00-5. 

Tetrafluoroetiiylene Tetrafluoroethylene-co-perfluoroalkyl vinyl ether Dynamic mechanical studies II had 98 or 99 mol% tetrafluoroethylene Runt et al. (1995)... 

RS 24 Perfluoroalkyl vinyl ether-tetrafluorethylene-perfluoropropylene copolymer (EPE). 

TEFLON" FEP was commercialized in 1959. At that time there appeared to be no hope of synthesis of a thermoplastic perfluorinated polymer of any structure other than FEP. Within two years the situation had changed as the result of a series of unexpected discoveries. For several years, research on the synthesis of perfluorocarbon epoxides had been underway in Du Pont, culminating in the discovery of a route to hexafluoropropylene epoxide (HFP0 )[5]. By 1960 sufficient HFPO had been made to permit exploration of its polymerization. This work shortly turned up an unusual polymerization system consisting of CsF initiator and polyethylene glycol ether solvent. Under the proper conditions this same system could be used to effect the condensation of HFPO with perfluorocarbon acid fluorides to produce perfluoroalkoxypropionyl fluorides [6]. These intermediates could be readily converted to perfluoroalkyl vinyl ethers by pyrolysis of their acid forms. 

Copolymerization of TFE with perfluoroalkyl vinyl ethers proved to be quite facile, either by dispersion techniques similar to that employed with FEP [7] or by a newly developed process ploying a fluorocarbon solvent. However, from the earliest studies it was evident that some complications had to be overcome. The most significant of these was a tendency for the alkyl vinyl ethers to rearrange when exposed to free radicals. In the extreme case a chain reaction could be initiated which would result in incomplete rearrangement to the isomeric acid fluoride. During polymerization at temperatures low enough to prevent excessive reaction by this route, the process, nevertheless, competes effectively with free radical coupling as a termination mechanism. 

The perfluoroaUcoxy polymers (PFA) described by Imbalzano and Kerbow contain 1-10% by weight of perfluoroalkyl vinyl ether (PAVE) and may also contain up to 5% by weight of a third monomer with one of the following structures ... 

PFA polymers are fully fluorinated and melt processible. They have chemical resistance and thermal stability comparable to polytetrafluoroethylene (PTFE). Melt viscosity of PFA is over one million times lower than PTFE. Perfluoroalkoxy resins are in general copolymers of tetrafiuoroethylene with one or more of perfluoroalkyl vinyl ether comonomers. Commercial examples of the latter include perfluoromethyl vinyl ether (PMVE), perfluoroethyl vinyl ether (PEVE), and perfluoropropyl vinyl ether (PPVE). PFA resins are specified by ASTM Method D3307, which also provides procedures or references to other ASTM methods for the measurement of resin properties. Commercial PFA resins offered by major manufacturers have been listed in Tables 6.1 through 6.7. 

Perfluoroethyl Vinyl Ether - Also see Perfluoroalkyl Vinyl Ether. 

Perfluoromethyl Vinyl Ether - See Perfluoroalkyl vinyl ether. 

Tetrafluoroethylene-c<7-perfluoroalkyl vinyl ether Trifluoroethylene-co-vinylidene fluoride... 

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