682: The Sonorheometer: A New Setup for Rheological Analysis upon Ultrasonication

Nowadays, ultrasound (US) is widely used in industry and research in various applications, including controlled drug release, and viscosity control of formulations. To investigate the rheological properties of such formulations upon an ultrasonic trigger, a new setup was developed, allowing in situ rheological measurements during ultrasonication. Our Sonorheometer consists of a rheometer in a plate‑plate geometry with a custom-made bottom plate, allowing the fixture of an ultrasonic transducer (28 kHz or 1MHz) and introduction of a corresponding trigger into the sample. Ultrasound in the low kHz­­­-range has shown promising effects regarding a decrease in viscosity in numerous thixotropic systems in literature.[1]^,[2] To efficiently drive the US transducer a continuous sine signal is applied with a waveform generator in combination with a power amplifier, custom-made for the low kHz‑range. Further implementation of a PTFE‑stamp in place of a common metal stamp provides the necessary damping properties while exhibiting chemical and thermal stability. The presented work will focus on the impact of US on the rheological behavior of different samples highlighting industrially relevant showcase examples as well as potential applications for this new device.