PVDF copolymer is an upgrade version of the hexafluropropylene monomer. With more flexibility and crystallinity, PVDF copolymer improves the stress crack resistance weld ability.
PVDF copolymer is also used in piezoelectric and electrostrictive applications. One of the most commonly-used copolymers is PVDF-trifluoroethylene in ratios of about 50:50 wt% and 65:35 wt%. Another one is PVDF-tetrafluoroethylene. They improve the piezoelectric response by improving the crystallinity of the material. The copolymers have a much higher crystallinity. This results in a larger piezoelectric response.
As Chinese PVDF copolymer is becoming more accepted in a wide range of applications, many of the unique properties are being utilized to develop new products. As these evolve, new standards are being developed to define the copolymer resins.