English
Español
In 1969, researchers discovered that PVDF has a strong piezoelectric effect: the piezoelectric coefficient of the polarized (that is, put in a strong electric field to generate a net dipole moment) film is 6-7pC/N, which is higher than that of the polymers that had been discovered at that time. The value is more than 10 times larger. [3]
PVDF has a glass transition temperature (Tg) of approximately −35°C and typically has a crystallinity of 50–60%. To impart piezoelectric properties to a material, the material is usually mechanically stretched along the direction of the molecular chain, and then polarized under tension. PVDF has a variety of solid phases: α phase (TGTG'), β phase (TTTT) and γ phase (TTTGTTTG'). The difference between these phases is whether the molecular chain is cis (T) or trans (G). PVDF will become a ferroelectric polymer after polarization, which has good piezoelectricity and pyroelectricity. These properties make it suitable for the production of sensors and batteries. For example, the sensors of some new thermal imaging cameras use PVDF films.
Unlike some other piezoelectric materials, such as PZT, PVDF has a negative d33 value. In a physical sense, this means that PVDF contracts when other materials expand in an electric field, and vice versa.
Suzhou Shincell New Material Co., Ltd. is a professional Foam Sheet Manufacturers. If you need it, you can click the official website to contact us. We are willing to answer you for more information.
++86-0512-66079229
