[PEEK]

Hello, I would need some help regarding ferroelectric polymers. I know that ferroelectrics have piezoelectric properties. For piezo, they don't have a permanent dipole moment and the fact of compressing them for example will create a dipole moment and thus allow electrons to circulate. But for a ferro, the dipole moment is permanent. So how will compressing our material for example allow the creation of an electric current? Will this compression reduce the dipole moment, and therefore the electrons will circulate from one surface to another to balance the charges? And what happens when our material is stretched?
Thanks in advance for your help.

[Corribus]

For piezo, they don't have a permanent dipole moment

Piezoelectric materials can have a permanent dipole moment. In fact about half of the crystal classes that are capable of being piezoelectric are formally polar crystal classes (pyroelectric).