Every day we get in contact with many materials of different flow or deformation behavior (e.g. liquids, gels, pastes, melts, elastomers). To understand and quantify their viscoelastic behavior, rheological measurements are performed. Several rheometric principles can be applied to determine these specific material parameters of fluidity, viscosity and elasticity.

By using and our present equipment and adapting / developing this for special sample characteristics and research issues, we are able to measure almost all kind of materials to characterize their rheological behavior.

 Our commercial devices are:

o Physica MCR 301 (Anton Paar)

o Anton Paar MCR 502 WESP

Used measuring geometries:

o Plate-Plate (25;40;50mm)
o Cone-Plate (25/0.5;50/1)
o Concentric Cylinder CC27
o Double-Gap DG42

Rheo-optical measurements can be performed using a special Twin-drive setup of the Anton Paar MCR 502 WESP rheometer in combination with a Photron High-speed camera.

An example:
The simultaneous high speed imaging and rheology of a foam.

Twin – drive

PP50 QG (quarz glass) / PP50 (QG)
inverse rotation

Frame rate: 10 800fps Shutter 1/30000s

Piezo rheometer

A plate -plate rheometer for small sample volumes

- Sample size (typical)
  • thickness: 10 – 500 μm
  • area: max. 2 cm2
  • volume: > 10 μL

- Frequency: 0.1 Hz – 1 kHz
- Deformation: < 300 nm
- Dynamic range: 10 – 10^6 Pa
- Transparent cell

Yamamoto, Y., H. Nakamura and K. Okano (1986).
"Apparatus for Measurement of Complex Shear Modulus of Liquid Crystaks at Low Frequencies."
Jap. J. Appl. Phys. 26-1: 29-31.

Roth, M., M. D'Acunzi, D. Vollmer and G. K. Auernhammer (2010).
"Viscoelastic rheology of colloid-liquid crystal composites." Journal of Chemical Physics 132, 124702.
https://doi.org/10.1063/1.3358331

T. Athanasiou, G. K. Auernhammer, D. Vlassopoulos, G. Petekidis (2019).
“A high-frequency piezoelectric rheometer with validation of the loss angle measuring loop: application to polymer melts and colloidal glasses” Rheological Acta 58, 619 – 637.
https://doi.org/10.1007/s00397-019-01163-x