Rheolaser ® MASTER enables the analysis of rheological properties of soft materials without mechanical stress (by passive microrheology). It is particularly suited for viscoelastic evolution monitoring: sol-gel transitions, changes due to aging or structure recovery. Based on diffusing wave spectroscopy (DWS) it provides highly sensitive monitoring of the smallest structure changes without contact.

Rheolaser ® MASTER is based on Multi Speckle Diffusing Wave Spectroscopy (MS-DWS) and detects particle Brownian motion. A thorough analysis of wave interferences due to particle mobility provides information about the rheological properties of the structure. In a strong gel (viscoelastic systems) particle mobility will be partially limited by the network structure. While in a simple viscous media, the mean square displacement (MSD) will have more linear form.

Monitoring MSD over time and temperature allows to monitor gel formation, determine sol-gel transitions and characterize gel strength with extreme accuracy and without any contact with the sample.

KEY BENEFITS

NON-CONTACT RHEOLOGY

- Weak structure characterization (weak gels, emulsions…)

- Long term analysis without stress or resampling.

- Gel formation monitoring without intervention.

A SIMPLE EXPERIMENTAL SET-UP

- Easy sample manipulations, no calibration or geometry setting

- 6 sample positions for simultaneous measurement

- Fully automated data treatments

GEL POINT DETERMINATION

- A complete viscoelastic analysis: gel formation, gel strength, viscosity and elasticity indices.

- Gel point determination as a function of multiple parameters (temperature, time, pH, concentration…)