Poly vinylidene Fluoride PVDF

Poly(vinylidene fluoride) (PVDF) Ethylene-chlorotrifluoroethylene copolymer Ethylene-tetrafluoroethylene copolymer Poly(vinyl fluoride) (PVF)... 

ISO 4433-4 1997 Thermoplastics pipes - Resistance to liquid chemicals - Classification -Part 4 Poly(vinylidene fluoride) (PVDF) pipes ISO 9393-2 1997 Thermoplastics valves - Pressure test methods and requirements - Part 2 Test conditions and basic requirements for PE, PP, PVC-U and PVDF valves ISO 10931-1 1997 Plastics piping systems for industrial applications - Poly(vinylidene fluoride) (PVDF) - Part 1 General... 

ISO 10931-2 1997 Plastics piping systems for industrial applications - Poly(vinylidene fluoride) (PVDF) - Part 2 Pipes... 

Gel polymer lithium-ion batteries replace the conventional liquid electrolytes with an advanced polymer electrolyte membrane. These cells can be packed in lightweight plastic packages as they do not have any free electrolytes and they can be fabricated in any desired shape and size. They are now increasingly becoming an alternative to liquid-electrolyte lithium-ion batteries, and several battery manufacturers. such as Sanyo. Sony, and Panasonic have started commercial production.Song et al. have recently reviewed the present state of gel-type polymer electrolyte technology for lithium-ion batteries. They focused on four plasticized systems, which have received particular attention from a practical viewpoint, i.e.. poly(ethylene oxide) (PEO). poly (acrylonitrile) (PAN). ° poly (methyl methacrylate) (PMMA). - and poly(vinylidene fluoride) (PVdF) based electrolytes. ... 

Poly (styrene sulfonic acid) grafts have also been attached to poly(ethylene-co-tetrafluoroethylene) (ET-FE) 8,29 poly(vinylidene fluoride) (PVDF) as shown in Figure 7. These materials were synthesized... 

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 Polytrifluoromonochloroethylene (PCTFE, Kel F) (Equation 6.54), in which one fluorine atom has been replaced by a chlorine atom, has a less regular structure and is thus more easily processed.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

The fluoropolymer family consists of polymers produced from alkenes in which one or more hydrogens have been replaced by fluorine. The most important members of this family are polytetrafluoroethylene (PTFE) (XLVII), polychlorotrifluoroethylene (PCTFE) (XLVIII), poly(vinyl fluoride) (PVF) (XLIX), poly(vinylidene fluoride) (PVDF) (L) copolymers of... 

G. Laroche, Y. Marois, R. Guidoin, M.W. King, L. Martin, T. How, Y. Douville, Poly-vinylidene fluoride (PVDF) as a biomaterial From polymeric raw material to monofilament vascular suture, J. Biomed. Mater. Res. 29(12) (1995) 1525-1536. 

Tlie use of polymer blends has been a very important approach in the development of new materials for evolving applications, as it is less costly than developing new polymers. The compatibility of poly(vinylidene fluoride) (PVDF) with various polymers has been comprehensively evaluated and has led to useful applications in coatings and films. Poly(methyl methacrylate) has been the most studied compatible polymer with PVDF owing to cost and performance advantages. Other acrylic polymers such as poly(ethyl methacrylate), poly(methyl acrylate), and poly(ethyl acrylate) have also been found to be compatible with PVDF. ... 

Coleman et al. 2471 reported the spectra of different proportions of poly(vinylidene fluoride) PVDF and atactic poly(methyl methacrylate) PMMA. At a level of 75/25 PVDF/PMMA the blend is incompatible and the spectra of the blend can be synthesized by addition of the spectra of the pure components in the appropriate amounts. On the other hand, a blend composition of 39 61 had an infrared spectrum which could not be approximated by absorbance addition of the two pure spectra. A carbonyl band at 1718cm-1 was observed and indicates a distinct interaction involving the carbonyl groups. The spectra of the PVDF shows that a conformational change has been induced in the compatible blend but only a fraction of the PVDF is involved in the conformational change. Allara M9 250 251) cautioned that some of these spectroscopic effects in polymer blends may arise from dispersion effects in the difference spectra rather than chemical effects. Refractive index differences between the pure component and the blend can alter the band shapes and lead to frequency shifts to lower frequencies and in general the frequency shifts are to lower frequencies. 

Screening tests were conducted on potential construction materials. The candidate materials evaluated included the following polytetrafluoroethylene (PTFE, TFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy-alkanes (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), ethylene-chlorotrifluoroethylene copolymer (E-CTFE), poly vinylidene fluoride (PVDF), polypropylene (PP), and polyvinyl chloride (PVC). These materials were chosen based on cost, availability, and information from manufacturers on compatibility with acid solutions. 

The last column of Table 2 lists the values of k calculated from Eq. (103). In the calculation, s at 1 MHz was used and Poisson s ratio m was assumed to be 0.35. Agreement between observed values and calculated ones is fairly good except for poly (vinylidene fluoride) (PVDF) and poly (methyl methacrylate) (PMMA), which exhibit a remarkable dielectric relaxation at room temperature. 

A close correlation between the polarities of piezoelectricity and pyroelectricity was found for PVC and poly (vinylidene fluoride) (PVDF) films (Nakamura and Wada, 1971). However, it must be emphasized that the polarity of piezoelectricity is determined not only by the polarity of the charge distribution but also by that of heterogeneous strain. The origin of heterogeneous strain in the elongation of film may derive from heterogeneity in the structure of the film. 

Examples of fluoroplastics include polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), ethylene—chlorotrifluoroethylene (ECTFE), ethylene—tetrafluoroethylene (ETFE), poly(vinylidene fluoride) (PVDF), etc (see Fluorine compounds, organic). These polymers have outstanding electrical properties, such as low power loss and dielectric constant, coupled with very good flame resistance and low smoke emission during fire. Therefore, in spite of their relatively high price, they are used extensively in telecommunication wires, especially for production of plenum cables. Plenum areas provide a convenient, economical way to run electrical wires and cables and to interconnect them throughout nonresidential buildings (14). Development of special flame-retardant low smoke compounds, some based on PVC, have provided lower cost competition to the fluoroplastics for indoors application such as plenum cable, Riser Cables, etc. 

Tn the early 1960s it was discovered in our laboratory (20) that poly-- (methyl methacrylate) (PMMA) and poly(vinylidene fluoride) (PVdF) were compatible when blended in the melt. Similarly, compatibility was found for poly (ethyl methacrylate) (PEMA) with PVdF. Blends of the fluorinated polymer with higher alkyl methacrylate polymers, however, were nonhomogeneous. 

Poly(vinylidene fluoride) (PVDF) Ethylene-chlorotrifluoroethylene copolymer... 

Poly(vinylidene fluoride) (PVDF) is the second most important thermoplastic within the fluoropolymer family after PTFE. Although, both the thermal and chemical stability of PVDF are somewhat lower compared to PTFE, the hydrogenated polymer can be more easily processed with conventional equipment, and it offers an advantageous compromise between quality and price. When the... 

Figure 7.2. Comparison of the cloud-point behavior of poly(vinylidene fluoride) (PVDF), 78 mol % vinylidene fluoride and 22 mol % hexafluoropropylene (VDF-HFP22), and 81 mol % tetrafluoroethylene and 19 mol % hexafluoropropylene (TFE-HFP19) in C02. The polymer and copolymer concentrations are 5 wt % in each case. The demarcations L + L and FLUID denote a two-phase and a one-phase region, respectively.

The preceding structural characteristics dictate the state of polymer (rubbery vs. glassy vs. semicrystalline) which will strongly affect mechanical strength, thermal stability, chemical resistance and transport properties [6]. In most polymeric membranes, the polymer is in an amorphous state. However, some polymers, especially those with flexible chains of regular chemical structure (e.g., polyethylene/PE/, polypropylene/PP/or poly(vinylidene fluoride)/PVDF/), tend to form crystalline... 

To get relevant information about active materials, the working electrode is made as similar as possible to the electrode of an operational device. However, current collectors are usually made with corrosion resistant materials, with good electronic conductivity, and no concern is taken about its relative mass. Materials such as gold, platinum, and vitreous carbon are commonly used. The active mass is usually tested in small amounts, mixed with electronically conducting materials, such as acetylene black, and a binder, such as poly vinylidene fluoride PVDF or polytetrafluoroethylene. The working electrode may be flat, with a 1 cm2 surface, for example, a rotating disk electrode (RDE), or a microcavity electrode, or any geometrical convenient electrode. 

Jin et al. (65) used poly(vinylidene fluoride) (PVDF) as a compatibilizer to assist dispersion of CNTs in PMMA. Multi-walled carbon nanotubes were first coated with PVDF and then melt-blended with PMMA. Poly(vinylidene fluoride) served as an adhesive to improve wetting of CNTs by PMMA and to increase the interfacial adhesion resulting in improved mechanical properties of MWCNT-PMMA composites. 

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