PVDF Kynar

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 Polytrifluoromonochloroethylene (PCTFE, Kel F) (Equation 6.54), in which one fluorine atom has been replaced by a chlorine atom, has a less regular structure and is thus more easily processed.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. 

Polyvinylidene fluoride (PVDF) (Kynar) has the following repeating unit ... 

Vinylidene fluoride PVDF Kynar (Pennsalt Chemicals)... 

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. 

Figure 3.117 Insoluble fraction of PVDF (Kynar ) homopolymer after electron beam irradiation.

Figure 6.5 Shear stress vs shear rate of PVDF Kynar homopolymer at 232°CP ...

Titanium Pt chloFoprene (Neoprene(S4 Polyester terephthalate (PET) Perfiuoroalko] (PF Perfiuoroelastomers (Fm, Kaliez , Chemraz , Kd-F ) Polypropylene (except TEA) Polysulfone (except TEA) Polyvinylldene fluoride (PVDF, Kynar ) (TEA only) Vinyl ester... 

FIGURE 10.10 The increasing trend of HEWL heterogeneous nucleation rate with porosity for modified PVDF Kynar and PVDF Kynarflex membranes (protein dissolved in 0.05 M sodium acetate buffer pH 4.5 and mixed 1 1 to NaCl solution as precipitant. Final concentrations protein 40 mg/ml NaCl 2.5%-3% w/v). (Adapted with permission from Curcio et al., J. Phys. Chem. B, 114, 13650-13655. Copyright 2006 American Chemical Society.)... 

Kinetic data for various modified PVDF Kynar/Kynarflex m branes characterized by different morphologies, measured for HEWL solutions with different precipitant concentrations, are cumulatively plotted in Figure 10.10. A qualitative increase of the nucleation rate with porosity is observed, in agreement with the tendency of the nucleation barrier AG to decrease at higher porosity. 

Atofina -France, USA www.atofina.com (Paris) www.atofinachemical8.com (USA) Largest capacity VDF and PVDF producer expansion underway 2002 Ausimont-USA www.ausimont.com Large capacity VDF and PVDF KYNAR, KYNAR 500, KYNAR FLEX, KYNAR Superflex, KYNAR Powerflex, HYLAR... 

Polyvinylidenefluoride (PVDF/Kynar/Hylar) has good mechanical and chemical resistance. It is microwave transparent and it is commonly used in connectors, valves, diffusion membranes, and screws. 

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

Figure 13.109 Insoluble fraction of PVDF (Kynar ) homopolymer after electron beam irradiation.(See Ch. 6 for information about the grades.)...

Except in cases where the outer layer is acrylic, for example, Acryhgard (Rohm Haas) or PVDF (Kynar ), vinyl siding is extmded in dual layers, mainly an inner layer, substrate, and the outer weatherable layer, capstock. (The terms come firom siding jargon that predates the appearance of PVC.) The bulk of the product is, of course, substrate, which uses reverse ester tin stabilizers ... 

PVC - LacovyI PVC - Sunprene PVDF - Kynar TPE PEBA - Pebax... 

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