Poly vinylidene difluoride

Gozdz et al. (of Bellcore) [25] recognized that poly (vinylidene difluoride) hexafluoropropylene (PVDF HFP) copolymers could form gels with organic solvents and developed an entire battery based on this concept. Typically, the gel separator is 50 pm thick and comprises 60wt. % polymer. In the Bellcore process the separator is laminated to the electrodes under pressure at elevated temperature. The use of the PVDF HFP gelling agent increases the resistivity of the electrolyte by about five times which limits the rate capability of such batteries. 

Shi, Z. Q., and Holdcroft, S. 2005. Synthesis and proton conductivity of partially sulfonated poly([vinylidene difluoride-co-hexafluoropropylene]-b-styrene) block copolymers. Macromolecules 38 4193-4201. 

Amido black dye Two years later, Grassman and Hanning developed another organic dye to be used on filter paper after electrophoresis amido black stain. It has moderate sensitivity. Today, amido black dye is used for colorimetric determination of electroblotted proteins on PVDF (poly-vinylidene difluoride) and nitrocellulose membranes. 

Mozdzanowski, J., Hembach, P., and Speicher, D. 1992. High yield electroblotting onto poly-vinylidene difluoride membranes from polyacrylamide gels. Electrophoresis 13 59-64. 

Reig, J. and Klein, D. 1988. Submicrogram quantities of unstained proteins are visualized on poly-vinylidene difluoride membranes by transillumination. Appl. Theor. Electrophor. 1 59-60. Speicher, D.W. 1989. Microsequencing with PVDF membranes Efficient electroblotting, direct protein adsorption and sequencer program modifications. In Techniques in Protein Chemistry (T.E. Hugh, ed.) pp. 24-35. Academic Press, San Diego. 

Sanchez, J. C., Ravier, F., Pasquali, C., Frutiger, S., Paquet, N., Bjellqvist, B., et al. (1992) Improving the detection of proteins after transfer to poly vinylidene difluoride membranes. Electrophoresis 13, 715-717. 

Blais J. C Nagnan-Le Meillour P Bolbach G. and Tabet J. C. (1996) MALDI-TOFMS identification of odorant binding proteins (OBPs) electroblotted onto poly(vinylidene difluoride) membranes. R. C. Mass Spectrom. 10, 1—4. 

PTV PU PVA PVAC PVAL PVC PVDC PVDF PVE PVF PXRD py Py PY Py-GC-MS pyr pyrr pz programmed-temperature vaporizer polyurethane poly (vinyl alcohol) poly(vinyl acetate) poly (vinyl alcohol) poly (vinyl chloride) poly(vinylidene dichloride) poly(vinylidene difluoride) poly (vinyl ether) poly(vinyl fluoride) powder X-ray diffraction pyridine (ligand) pyridine pyramidal (coordination compounds) pyrolysis-gas chromatography-mass spectrometry pyrazine (ligand) pyrrolidine (ligand) pyrazole (ligand)... 

PAH PES PTPE PVD PVDP polycyclic aromatic hydrocarbon potential energy surface poly(tetrafluoroethylene) physical vapor deposition poly(vinylidene difluoride)... 

Figure 4.3 Piezoelectric poly(vinylidene difluoride) PVDF and its non-piezoelec-tric isomer, poly(ethylene-co-tetrafluor-oethylene) (ETFE) [6].

PVDF poly(vinylidene difluoride) TN twisted nematic... 

The aromatic polyimides, cited earlier, separate carbon dioxide over methane with a-valves of 150-160. Aromatic polyoxadiazoles have a-valves of 100-2 00.157 The permeability of one aromatic polyimide was improved by two to four orders of magnitude by carbonizing it on porous alumina,158 the final a-valve being 100. In this case, the final actual membrane was probably a porous carbon molecular sieve. Facilitated transport has also been used to increase the separation factor. A porous poly(vinylidene difluoride) membrane with ethanolamine or diethanolamine in the pores gave a separation factor of carbon dioxide over methane of 2000.159 Such a method is less energy-intensive than when an amine is used in the usual solvent method. 

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