Center Smart Materials and Adaptive Systems CeSMAPolyvinylidenfluoride is a polymer frequently used as high performance dielectric or protection coating. The material has also piezoelectric properties when stretched and poled.
Since several years, the copolymer Polyvinylidenfluoride-trifluoethylene is investigated as piezopolymer. This polymer is self-oriented, a stretching step can be omitted. Thereby, it is feasible to print the polymer reducing material consumption and better freedom of design. The sensors are very thin and can be manufactured by printing techniques, for example on cost-effective flexible polymer or paper substrates. Using transparent electrode materials, the produced sensors are transparent. Reliability experiments revealed excellent results. The sensors can also be directly printed on selected textile fabrics.
The material is highly sensitive, even smallest events can be monitored by PVDF-TrFE sensors and sensor arrays. CeSMA has developed different formulations for different printing techniques and has developed various applications together with partner organizations, such as Joanneum Research (Austria). These were human-machine interfaces, touch-screens for flexible displays, sensors for technical rolls amongst others.
By adding piezoceramic nanoparticles and by application of certain poling techniques, the pyro- and piezoelectric effect can be enforced or suppressed separately.