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Polyvinylidenefluoride PVDF

Tm = 160-180 °C. PVDF has been blended mainly with PMMA (Lin and Burks 1993). The blends are suitable for the use as stable electrets or weather-resistant architectural coatings. Nearly 25 wt% of PVDF consumption is in weather-resistant architectural spray finishing or coating to metals, roofing, curtain walls, wall panels. [Pg.62]

Ethylene-earbon monoxide-vinyl chloride copolymer, /Ucryn blends Loomis and Statz 1984,1986 [Pg.63]

PA-1212, or PARA and poly(ethylene-co-alkyl (meth)acrylate-co- Hohnaim 1994 vinyl acetate-co-CO-co-maleic anhydride)  [Pg.63]

PVDC-VC with vinylidene chloride-methyl acrylate copolymer (PVDC-MeA) Paleari and Frunasiero 1994 [Pg.63]

30 wt% PMMA for outdoor films with good clarity, chemical, and UV stability Koblitz et al. 1966 [Pg.63]


Polyarylate (PAR)-b-PSt and PAR-b-PMMA for compatibiiizers are described 135,39,40). The addition of PAR-b-PSt (1-10 parts) to 100 parts of a blend of PAR-PSt (7w-3w) resulted in improvement of the tensile and flexural modulus (Fig. 4), and PSt dispersed particles were diminished from 1-5 microns to an order that is undetectable by SEM, indicating the excellent, compatibilizing effect of the block copolymer. The alloy thus formed exert the characteristic of PAR, an engineering plastic, as well as easy processability of PSt. Addition of PAR-b-PMMA (3 or 8 parts) to 100 parts of a blend of PAR-polyvinylidenefluoride (PVDF) (7w-3w) resulted in improved microdispersed state of PVDF due to compatibility of PMMA with PVDF, while segregation of PVDF onto the surface was controlled. [Pg.761]

The ultrafiltration unit, containing submerged polyvinylidenefluoride (PVDF) hollow-fiber membranes (ZeeWeed by Zenon), is designed to treat 1600 m3/h of wastewater with a COD/h of445 kg and the suspended matter of the treated water is <1 mg/L [21]. [Pg.273]

Microfiltration membranes can be used as pretreatment for other membrane technologies and to remove microbes and total suspended sohds (TSS) including fibers and particles. Retention of salts and dissolved organics is negligible, if they are not bound to the suspended sohds. MF can be used for the recovery of coating color pigments. MBRs generally use UF or MF membranes. The materials used in microfiltration are polyvinylidenefluoride (PVDF), polypropylene, polyethylene, polysulfone, polyether suUbne, Teflon, and ceramic materials. [Pg.985]

The electrodes for examination were produced by smearing of suspension of active materials in the solution of binding substance -polyvinylidenefluoride (PVDF) - on the metal substrate by means of applicator "Doctor Blade" by Hohsen Corp. N-methyl-2-pyrrolidone was used as the solvent for the binding substance. [Pg.260]

Polyvinylidenefluoride (PVDF) and polymethylmethacrylate have been known to be a thermodynamically miscible blend exhibiting a single T, an indication of a single phase behavior [Bernstein et al., 1977 Mijovic et al., 1982]. A commercial PVDF/PMMA blend film (Fluorex A, Rexham Corp.) produced captively by solvent casting is used in specialty applications, such as a protective and decorative overlaminated for... [Pg.1058]

SWNT/polymer composites could also be made by a two-step fabrication process. For example, SWNT films were first fabricated on glass slides via Mayer rod coating, and then polymers such as PVA, Nafion and polyvinylidenefluoride (PVDF) were infiltrated into SWNT networks. As the polymer occupied the empty space between the nanotubes, a freestanding... [Pg.192]

The possibility to efficiently remove carbon dioxide by membrane contactors has been demonstrated by many researchers. Yeon and coworkers, for example, applied a pilot-scale membrane contactor hybrid process to recover CO2 from flue gas [3], They used a polyvinylidenefluoride (PVDF) hoUow-flber (HF) membrane module, realized at KRICT (Korea) for treating a gas mixture made of 11 vol% CO2 and 89 vol% N2 with an absorbent stream containing 0.34 M triethanolamine (TEA) and 0.82 M monethanolamine (MEA). The gas... [Pg.773]

Due to its doubled fluorine atoms, polyvinylidenefluoride (PVDF), is even less affected by the environment than is PVF (including its property of fire retardance) and stands between PVF and the superior chemical properties of PTFE. However, PVDF has far better mechanical properties than PTFE. It is also used as a top coat to protect PVC coatings against environmental influences. [Pg.36]

Figure 10.2. Optical absorption spectra of a solution of PeZn in A, iV-dimethylacetamide (—) compared with thin films of PeZn drop coated from a mixed solution of PeZn and polyvinylidenefluoride (PVDF ), and PeZn vapor deposited at room temperature (a phase ----) or after annealing at 573 K for 3 hr phase --). Figure 10.2. Optical absorption spectra of a solution of PeZn in A, iV-dimethylacetamide (—) compared with thin films of PeZn drop coated from a mixed solution of PeZn and polyvinylidenefluoride (PVDF ), and PeZn vapor deposited at room temperature (a phase ----) or after annealing at 573 K for 3 hr phase --).
Asymmetric and composite membranes commercially known as HYFLON AD are obtained from copolymers of tetrafluoroethylene (TFE) and 2,2,4-trifluoro-5-trifluoromethoxy-l,3-dioxole (TTD) these membranes show a high hydrophobic character with contact angles to water greater than 120° (Arcella et al. 1999). Hydrophobic membranes from copolymers of polytetrafluoroethylene (PTFE) and polyvinylidenefluoride (PVDF) were prepared by a phase inversion process (Feng et al. 2004) these membranes exhibit excellent mechanical properties and good hydrophobicity (contact angle to water of about 87°). [Pg.336]

Polymeric microporous hydrophobic membranes, typically polytetra-fiuoroethylene (PTFE), polypropylene (PP) and polyvinylidenefluoride (PVDF), are major membrane materials. Modified hydrophilic membranes such as cellulose acetate and cellulose nitrate modified with plasma polymerisation, have also been successfully tested in MD operations (Lawson and Lloyd, 1997). Furthermore, modified inorganic membranes, such as ceramic membrane modified with CgFi7(CH2)2Si(OC2H5)3 perfluoroalkylsi-lane molecule (Cg) and carbon nanotube based membranes, have also been developed for MD (Susanto, 2011). [Pg.76]

In Fig 7.4 the integrated membrane process for the recovery of chromium salts from exhausted baths of the chromium tannage is reported. In the proposed process, the exhausted effluent is submitted to a pre-treatment step by UF, producing a strong reduction of suspended solids and fat substances. Spiral wound UF membranes in polyvinylidenefluoride (PVDF) with a MWCO of 25 kDa was able to reject these compounds at 84% and 98%,respectively. About 40% of organic nitrogen was retained by... [Pg.307]

Fouling is expected to be more severe with hydrophobic membranes. Polyvinylidenefluoride (PVDF), polypropylene (PP) and polyethersul-fone (PES) are typical materials used to manufacture commercial MBR membranes, because of their good mechanical and chemical resistance. Unfortunately, these materials are relatively hydrophobic (water-repelling, but organic- and oil-attracting) and require to be mixed with additives, such as polyvinylpyrrolidone (PVP) and methacrylates, before being used in aqueous media. [Pg.744]

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. [Pg.106]

Eisenmenger W, Haardt M (1982) Observation of charge compensated polarization zones in polyvinylidenefluoride (PVDF) films by piezoelectric acoustic step-wave response. Solid... [Pg.621]

Solvay Polyvinylidenefluoride, PVDF Solef Engineering Polymer, Br. 1292c-B-5-0485, Solvay Cie, Brussels, Belgium. [Pg.192]

Polyvinylidenefluoride (PVDF) Excellent chemical resistance, good chlorine resistance... [Pg.218]

All these factors make it difficult to develop a cost effective solution for the separator plates. Initial trials were with graphite polymer molded composites. The polymers that were tried includes polyvinylidenefluoride (PVDF), polyetheretherketone (PEEK), perfluoroalkoxy (PEA) etc. Although most of the graphite polymer composite passed the 200°C phosphoric acid test, few survived more than few thousand hours, when they are maintained in 200°C phosphoric acid with a potential of 1.0 V w.r.t. SHE. Of the various polymers, PFA was found to be the most suitable. However, it was observed that after long exposure to PAFC temperature, the polymers got relaxed, causing an increase in the plate electrical resistance and porosity. However, all these plates exhibited excellent gas crossover resistance at least in the initial phase. [Pg.202]

As known, the common evaluation approach for hydrophilic-hydrophobic properties of membrane is based on the evaluation of a contact angle formed between the Uquid-gas tangent and membrane-liquid boundary [22]. Most commercial membranes for pressure-driven processes are made from hydrophobic polymers with high thermal, chemical, and mechanical stabilities such as polyvinylidenefluoride (PVDF), polyethersulfone (PES), polysulfone (PS), polypropylene (PP), polyacrylonitrile (PAN), polyamide (PA), and polyethylene (PE) [23]. Usually these materials... [Pg.617]


See other pages where Polyvinylidenefluoride PVDF is mentioned: [Pg.410]    [Pg.411]    [Pg.424]    [Pg.429]    [Pg.25]    [Pg.465]    [Pg.58]    [Pg.45]    [Pg.305]    [Pg.47]    [Pg.544]    [Pg.62]    [Pg.617]    [Pg.3243]    [Pg.42]    [Pg.107]    [Pg.570]    [Pg.126]   


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PVDF

Polyvinylidenefluoride

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