Fluorinated ethylene propylene dispersions

FEP polymer, 10 220 18 306—307. See also Fluorinated ethylene propylene (FEP) Perfluorinated ethylene-propylene (FEP) copolymers applications of, 18 315—316 chemical properties of, 18 313 dispersion processing of, 18 314 economic aspects of, 18 315 effects of fabrication on properties of, 18 315... 

Teflon [Du Pont], TM for tetrafluoroethyl-ene (TFE) fluorocarbon polymers available as molding and extrusion powders, aqueous dispersion, film, finishes, and multifilament yam or fiber. The name also applies to fluorinated ethylene-propylene (FEP) resins available in the same forms. The no-stick cookware finishes may be of either type. Fibers are monofilaments made from copolymer of TFE and FEP. 

The family of fluorinated polymers that include polytetralluoroethylene, (PTFE), polychlorotrilluor-oethylene (PCTFE), polyvinylidenelluoride (PVDF), and fluorinated ethylene-propylene. These resins are characterized by good thermal and chemical resistance, nonadhesiveness, low dissipation factor, and low dielectric constant. They are available in a variety of forms, such as moldings, extrudates, dispersions, films, or tapes. 

Fluorinated ethylene-propylene resin (FEP, PFEP) n. This member of the fluorocarbon family is a copolymer of tetrafluoroethy-lene and hexafluoropropylene, possessing most of the desirable properties of PTFE, yet truly meltable and, therefore, process-able in conventional extrusion and injection-molding equipment. It is available in pellet form for those operations and as dispersions for spraying and dipping. 

For practical purposes there are eight types of fluoropolymers, as summarized in Table F.7. Included in this family of plastics are polytetrafluoroethylene (FIFE), polychlorotrifluoroethylene (PCTFE), polyvinyl fluoride (PVF), fluorinated ethylene propylene (FEP), and others. Depending on which of the fluoropolymers are used, they can be produced as molding materials, extrusion materials, dispersion, film, or tape. Processing of fluoropolymers requires adequate ventilation for the toxic gases (HF) that may be produced. 

In contrast to previous manufacturing approaches, it is proposed that the infusion of volatile precursors of inorganic and metal-oxide nanoparticles into free volume of polymers is a more practical and effective strategy for the dispersal of discrete nanoscale particles. To this end, hybrid films containing Pd nanoparticles have been obtained through infusion the metal nanoparticles have been shown to have a strong catalytic effect on the gas transport through fluorinated ethylene-propylene copolymer (FEP) (Yu etal.,2004). 

While fast polymerizations occurred in diethyl-, di Bu- and propylene carbonate (fcp PP = 3 - 3.3 X IQ-2 h- ), the fastest rates were provided by ethylene carbonate, HFIPA ( p PP = 5 - 7 X IQ-2 h i) and especially by dimethyl carbonate (DMC, app j jQ-i ii-i). The conversion, polymerization rate (A p PP), and PDI were largely insensitive to the amount of DMC, = 35 mL, 1 g VDF, 1-12 mL DMC), whereas the rate significantly increased with the amount of VDF pressure and monomer concentration in solution, with 1-4 g VDF, 3-12 mL DMC). These are typical features of heterogeneous polymerizations of gaseous monomers [114], reminiscent of precipitation/dispersion polymerization of PVDF in SCCO2 with [29] and without [115] iodine CTAs. However, while fluorination enhances polymer solubilization, SCCO2 is a very poor PVDF solvent [116], even at high temperatures and pressures. 

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