Polyvinylidene Fluoride Properties

In 1969, able piezoelectricity was empiric in PVDF, with the piezoelectric accessory of poled (placed beneath a able electric acreage to abet a net dipole moment) attenuate films as ample as 6–7 pC/N: 10 times beyond than that empiric in any added polymer.

Polyvinylidene Fluoride has a bottle alteration temperature (Tg) of about −35 °C and is about 50–60% crystalline. To accord the actual its piezoelectric properties, it is mechanically continued to acclimatize the atomic chains and again poled beneath tension. PVDF exists in several forms: alpha (TGTG'), beta (TTTT), and gamma (TTTGTTTG') phases, depending on the alternation conformations as auto (T) or gauche (G) linkages. If poled, PVDF is a ferroelectric polymer, announcement able piezoelectric and pyroelectric properties. These characteristics accomplish it advantageous in sensor and array applications. Attenuate films of Polyvinylidene Fluoride are used in some newer thermal camera sensors.

Unlike added accepted piezoelectric materials, such as PZT, PVDF has a abrogating d33 value. Physically, this agency that PVDF will abbreviate instead of aggrandize or carnality versa if apparent to the aforementioned electric field.