The PRINCESS project

Dependence on batteries

The entire market for mobile and wearable devices suffers from one major issue, namely the reliance on batteries. Especially in smart clothing scenarios, it is highly desirable to have autonomously powered flexible wireless sensor systems. To realize such self-powered systems, both an energy supply and an energy storage are required. Polymeric materials are a promising class of materials for both energy generation and storage while featuring the most important property for wearable applications: mechanical flexibility.


Piezoelectric polymers like polyvinylidenfluoride (PVDF) and its co-polymers like PVDF-TrFE proved repeatedly to be a good choice for energy harvesting. In addition, PVDF based capacitors can be utilized as energy storage units, although the capacity is rather limited. Nanocellulose (NC) based materials also show significant potential with respect to these applications.

The dielectric and piezoelectric properties of these materials are often limited in terms of their adjustability, but can be significantly enhanced and tailored by embedding high‑k or piezoelectric nanofillers (like TiO2 or BaTiO3) into the material matrix. One major challenge when integrating nanofillers is the interface between the material and the nanofiller.


PRINCESS is a cooperation between TU Wien, Shanghai University, V-trion GmbH textile research and Grabher Günter Textilveredlung GmbH. The two academic partners are investigating the potential of nanocomposites based on PVDF and nanocellulose. Untreated, functionalized nanoparticles coated with nanocellulose (nanocellulose acts like a "glue" between the polymer matrix and the nanoparticles) are embedded in both polymer materials. The resulting nanocomposite layers are characterized in terms of their mechanical, electrical and piezoelectric properties. For the first time, these investigations are carried out for nanocellulose films. In the project, both nanocomposites will be compared with each other and with commercially available PVDF films to assess their potential for wearable application scenarios. Grabher Günter Textilveredlung GmbH will then develop the manufacturing processes together with V-trion GmbH textile research to implement the nanocomposite materials in wearable devices.