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Oriented films polyvinyl fluoride

Candidates. The only commeroially available oriented films known at this time which fit the weather resistance requirements are polyvinylidene fluoride (PVF2)i polyvinyl fluoride (Tedlar), polymethyl methacrylate (PMMA), and polybutyl aorylate/methyl methacrylate copolymer (PBA/MMA). PVF2 is currently expensive. PBA/MMA is inexpensive but in clear form does not appear to be sufficiently oxidatively stable for our purposes. It is also too water sensitive and too easily softened in many laminating processes. PMMA appears to be somewhat more chemically stable than PBA/MMA and is also relatively Inexpensive, but has the same dimensional stability problems at 150°C, the normal pottant processing temperature. Both acrylics maintain excellent optical clarity on heat aging, however. [Pg.382]

The only known commercial producer of polyvinyl fluoride is DuPont Company. Tedlar is DuPont s trademark for oriented and unoriented films and three grades of PVF resin for special coatings applications. PVF films are tough, durable, preformed polyvinyl fluoride films that are manufactured in continuous rolls. PVF films can be oriented or nonoriented. Film thickness can range from 12.5 to 75 pm and can be treated for adherability or left untreated for release applications. [Pg.124]

Table 8.35. Properties of Biaxially Oriented Polyvinyl Fluoride Films> i... Table 8.35. Properties of Biaxially Oriented Polyvinyl Fluoride Films> i...
Certain polymers, such as polyvinylidene fluoride (PVDF) and polyvinyl fluoride (PVF), possess special properties in the film form, caileApiezoelectricity and pyroelectricity. Piezoelectricity is electric polarization of a film produced by mechanical strain in some crystals. The polarization is proportional to the amount of strain and changes sign with it. The reverse is true and an electrical polarization induces a mechanical strain in piezoelectric sensors. Pyroelectricity is electric polarization of a film induced by thermal absorption in some polymer crystals. The induced polarization is proportional to the level of thermal change. These properties can be used in the manufacture of transducers, microphones, loudspeakers, pressure gauges, pickup heads, hydrophones, motion sensors, and other devices from biaxially oriented PVDF films. Table 13.37 gives the properties of a piezoelectric film of polyvinylidene fluoride. [Pg.427]


See other pages where Oriented films polyvinyl fluoride is mentioned: [Pg.234]    [Pg.33]    [Pg.233]    [Pg.699]   
See also in sourсe #XX -- [ Pg.233 ]




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