Rheometry and Coupled Physical Measurement Platform

Our strain imposed rheometer ARES-G2 is equipped with a high-temperature oven and a connection to liquid nitrogen, allowing it to perform rheological measurements between -150 and 600°C, or under neutral gas. It is also equipped with a PPS geometry kit for aggressive samples. The DMA mode of the ARES-G2 also enables the testing of a sample with oscillations of up to 50µm amplitud at frequencies of up to 100Hz.

 This rheometer is equipped with the Anton Paar rheo-microscope accessory, allowing for observation of the sample under shear with magnifications ranging from x5 to x50. We also have modules for fluorescence studies and polarized light examination.

Versatile in nature, it is equipped with a rough large-gap Couette geometry, allowing for the study of charged fluids. A custom-made transparent Couette geometry is also available, enabling observation of sedimentation during measurements.

This highly sensitive rheometer is equipped with a 'Mooney Ewart' type geometry, mounted on an optical table and furnished with the necessary accessories for observing 'speckles'.

Ce rhéomètre polyvalent permet d’obtenir rapidement une courbe d’écoulement ou toute autre mesure standard. Il est équipé d’un module Couette thermostaté et de géométries rugueuses pour les échantillons glissants.

This rheometer allows for oscillatory measurements with an amplitude of 10 nm up to 10 kHz, on a sample with a reduced volume (maximum 200µm).

The Lovis, a rolling ball rheometer, is particularly suited for measuring the viscosity of low-viscosity newtonian liquids.

This viscometer allows for the characterization of the rheological properties of complex fluids under extensional stresses. This type of stress is frequently encountered in many industrial applications, during the formulation of products or during their shaping. 

Passive microrheology consists in quantifying the Brownian motion of micro-particles in a medium whose rheological properties are to be characterized.

Confocal image of a liquid containing fluorescent tracer particles (diameter 0.5 µm) and magnified view of a single tracer particle and its Brownian trajectory. 

The analysis of particle motion makes it possible to calculate their mean square displacement (MSD). In Newtonian liquids, viscosity can be measured over a wide range (from 10⁻³ Pa·s to 10 Pa·s). In purely elastic systems, the elastic modulus can be measured within a range of 0.1 to 20 Pa. The accessible frequency range extends from 0.1 to 20 Hz.

• The advantages of passive microrheology include:
  • The very small sample volumes required,
  • the ability to analyze heterogeneous samples,
  • in-situ monitoring of rheological properties.

Example of microrheology results on gel samples [D. Milian et al., Biomacromolecules 2023]. As prepared the gel is purely elastic and the MSDs are uniform and time-independent. After a pre-shear, microcracks are visible and tracer particles located in these microcracks exhibit much higher MSD and a diffusive behavior.