Kynar Poly

Charge Kynar Poly vinyldene fluoride Penwalt... 

Benzlnger, W. D. Parekh, B. S. and Elchelberger, J. L. "Ultra-filtration with Kynar Poly (Vlnylldlene Floinrlde) Meinbranes," Separation Science and Technology. Vol. 15, No. 4, 1193-1204,... 

Kynar Poly(vinylidene fluoride) Pennsalt Corp. 

In early work, Kynar poly(vinylidene fluoride), a thermoplastic material, was used to make the matrix. It was soon discovered that in concentrated phosphoric acid at high temperatures, it is not sufficiently stable chemically and produces fluorine-containing impurities tending to adsorb on the catalyst surface, lowering the catalyst s activity and with it the fuel cell s performance. 

The most chemical-resistant plastic commercially available today is tetrafluoroethylene or TFE (Teflon). This thermoplastic is practically unaffected by all alkahes and acids except fluorine and chlorine gas at elevated temperatures and molten metals. It retains its properties up to 260°C (500°F). Chlorotrifluoroethylene or CTFE (Kel-F, Plaskon) also possesses excellent corrosion resistance to almost all acids and alkalies up to 180°C (350°F). A Teflon derivative has been developed from the copolymerization of tetrafluoroethylene and hexafluoropropylene. This resin, FEP, has similar properties to TFE except that it is not recommended for continuous exposures at temperatures above 200°C (400°F). Also, FEP can be extruded on conventional extrusion equipment, while TFE parts must be made by comphcated powder-metallurgy techniques. Another version is poly-vinylidene fluoride, or PVF2 (Kynar), which has excellent resistance to alkahes and acids to 150°C (300°F). It can be extruded. A more recent development is a copolymer of CTFE and ethylene (Halar). This material has excellent resistance to strong inorganic acids, bases, and salts up to 150°C. It also can be extruded. 

The processability of fluorine-containing polymers is improved by replacement of one or more of the fluorine atoms. Replacing one of the eight fluorine atoms with a trifluoromethyl group gives a product called FEP or Viton, actually a copolymer of tetrafluoroethylene and hexafluoropropylene (Equation 6.53). Polytrifluoromonochloroethylene (PCTFE, Kel F) (Equation 6.54), in which one fluorine atom has been replaced by a chlorine atom, has a less regular structure and is thus more easily processed. Poly(vinylidene fluoride) (PVDF, Kynar) (Equation 6.55) is also more easily processable but less resistant to solvents and corrosives. 

All centrifuge surfaces that came into contact with lake water were either lined with or manufactured of poly(vinylidene fluoride) (Kynar) to reduce the possibility of contamination. 

Effects of additives in the matrix were observed by substituting for methyl methacrylate a poly (methyl methacrylate) homopolymer with a solution molecular weight of 950,000, a vinylidene fluoride copolymer (Pennwalt s Kynar 7201), and a methacrylate-butadiene-styrene impact modifier (Marbon s Blendex BTA IIIN). Concentrations were 2% on the total dispersion volume. The same additives were studied at the same volume concentration in the dispersed phase. Barium sulfate (Whittaker, Clark, and Daniels Barytes No. 91), a commonly used additive for radiopacity, was also studied in the dispersed phase. Responses were observed by the test methods described below. 

Yi et al. reported a new type of PVDF membrane prepared by blending two very different polymers, a PVDF fluoropolymer such as Kynar with a sulfonated poly-electrolyte. The new membrane is inexpensive and displayed good performance and durability based on 1,000-h test data. 

Mw = 320,000, Mn = 73,500) was obtained from Aldrich. The poly(2,6-dimethy1-1,4-phenylene oxide) sample was obtained from General Electric Co. (Mw = 69,000 Mw/Mn = 2.1). Poly(vinylidene fluoride), Kynar 881, was supplied by Pennwalt Corp., and poly(methyl methacrylate), Acrylite H—12, was supplied by the American Cyanamid Co. 

Polytetrafluoroethylene (PTFE Teflon) was discovered accidently by PlunkettCZ nd commercialized by DuPont in the 1940 s. This polymer has a solubility parameter of about 6H and a high melting point of 327°C and is not readily moldable. Poly-chlorotrifluoroethylene (CTFE, Kel-F), the copolymer of tetrafluoroethylene and hexafluoropropylene (FEP), polyvinylidene fluoride (PVDF, Kynar), the copolymer of tetrafluoroethylene and ethylene (ETFE), the copolymer of vinylidene fluoride and hexafluoroisobutylene (CM-1), perfluoroalkoxyethylene (PFA) and polyvinyl fluoride (PVF, Tedlar) are all more readily processed than PTFE. However, the lubricity and chemical resistance of these fluoropolymers is less than that of PTFE. 

Fluoropolymers. Melt processable fluoropolymers such as Teflon FEP, Tefzel ETFE, poly(vinylidene fluoride) (Kynar), and ethylene-chlorotrifluoroethylene copolymer (Halar) are suitable for wire insulation in special applications because they combine good physical properties with low flammability. They are used for instrumentation cable in process-control rooms, as well as for computer and aircraft wiring and in military applications. The... 

Poly (vinylidene fluoride) (PVDF). A representative of fluoropIastics, it is a chemical resistant thermoplastic for use between —40 and +150 °C. Applications pipes, fittings, pumps, packings especially for the chemical industry. Trade names Foraflon (F), Solef (B), Kynar (USA),... 

Kynarflex 2800 poly(vinylidenefluoride-co-hexafluoropropylene) Kynar 460 polyvinyli-denefluoride homopolymer DMA AfA -dimethylacetamide PVP polyvinylpyrrolidone (MW = 10,000) liCl lithium chloride. 

PVDF Poly(vinylidene fluoride) Kynar Pennwalt Chemical Company... 

Herrero and Acosta (80) investigated the microstmcture of poly(ethylene oxide)-poly[(octafluoropentoxy)(trifluoroethoxy)phosphazene] blends. Limited miscibility of both components was inferred, based on the observed shift of the components glass-transition temperatures. Wycisk and co-workers (81) prepared membranes from blends of sulfonated poly[bis(3-methylphenoxy)phosphazene] with polyimides, polyacrylonitrile, and Kynar FLEX PVDF. Morphology, electrochemical performance, and methanol permeabilities of the membranes were then evaluated as part of a program to investigate such blends in direct methanol fuel cells. The polymers were immiscible and a domain-type structure was observed. The best compatibility resulted when the tetrabutylammonium or sodium salt of the polyphosphazene was used (82). 

Poly(vinylidene fluoride) (PVDF) Kynar Pennwalt Pipe fittings, seals, laboratory ware, aircraft parts... 

Vinylidene fluoride (VF2) as well as vinyl fluoride (VF) resemble more ethylene than other vinyl monomers in regard to the properties and can also be polymerized in a manner analogous to that of ethylene. The first successful polymerization of vinylidene fluoride was reported by Du Pont in 1948 [517]. Poly(vinylidene fluoride) (PVF2 or PVDF) is commercially available from various companies (Kureha Chemical Co., Pennalt Chemicals Corp., Solvay Co., Siiddeutsche Kalkstickstoff-Werke AG now Degussa, Diamond Shamrock, Du Pont) since 1965 under the trade names KF, Kynar, Foraflon, Vidar, and Dalvor, respectively. VF2 can be polymerized by free-radical initiators to give high-molar-mass, crystalline polymers. 

MEDIA 200 F RYTON 200" f PENTON 00"F KYNAR 200 F TEFLON 200 F POLY-SULFONE 200 F noryl 200 F NYLON 200 F POLYCAR. 60NATE 316 S.S. CARBON STEEL f LU- MINUM (3003)... 

Fig. 15 Kinetics of grafting of the benzylamine (200%) onto a poly(VDF-co-HFP) copolymer Kynar containing 10 mole % of HFP. The grafting reaction is carried out in MEK at 80 °C [133]...

Kynar sheet Poly(vinylidene fiuoride) Pennwalt Chemicals Corp. 

---