Polymer with piezoelectric effect

[bio2000]

I am trying to find a polymer that can be expanded against pressure, as a result of piezoelectric or other mechanism; which can be manipulated and is expandable after applying some pressure between the fingers.

 

[btrueblood]

PVDF = poly vinylidene fluoride. This from wikipedia.

PVC also supposedly.

I doubt either is as efficient as some of the ceramic materials. None of the materials will expand very much without hazardous levels of voltage for an object being held.