The DWS RheoLab: From Microrheology to Macrorheology

 
 

The need to understand the mechanical properties of natural or formulated substances containing small particles has become a main field of interest for many laboratories working on polymers, surfactants, micelles, thickeners, etc.

With the DWS RheoLab such crucial information can be accessed conveniently and quickly using a novel principle for optical rheology: The instrument monitors the thermal motion within the sample with nanometer resolution  using Diffusing Wave Spectroscopy (DWS) and automatically translates this information into rheological data. This approach is called microrheology and the obtained data can directly be compared to what a conventional mechanical rheometer measures in oscillatory mode in the linear viscoelastic regime.

 

 

"Optical microrheology has emerged as one of the most important new techniques to study and characterize rheological properties of complex fluids!"

Dr. Frédéric Cardinaux, Food Colloids, 2007

 

 

 
 
  • Fully automated DWS Microrheology
  • Applicable to all homogeneous transparent or opaque samples
  • Fluid with a large range of viscosities from 0.1 mPa∙s to 1000 Pa∙s can be measured
  • Storage and loss moduli G'(ω), G''(ω)  in a frequency spectrum 0.1 Hz to 1 MHz (0.1 Hz to 10 MHz with pseudo cross-correlation upgrade)
  • Elasticity range from 1 Pa to 50 kPa
  • Computes the mean square displacement (MSD) of particles
  • Contact-free. No mechanical force applied to the sample: ideal for stability or shelf life studies
  • Monitors time-dependent processes
  • Regulated sample temperature from 4°C to 110°C*
  • Temperature stability < 0.02°C*
  • Compact and robust design
  • Several cuvette sizes available
  • Sample quantity down to 150 μl (for 1 mm thick sample cell)
  • Several options available
  • Particle sizing at high concentrations 
  • Online support forum for all customers

 

*: Climate controlled room at or below 23° C is required to meet these specifications, minimum temperature cannot be below the dew point. For measurements below the dew point, a dry air source must be connected to avoid condensation. 

 


Download the brochure:

 


Download detailed specification file:

 


Register:

>> DWS & Microrheology Newsletter

 


Learn more about possible applications:

>> Application Notes DWS

 


Check the list of scientific publications which are based on results obtained by our customers from a DWS tool by LS Instruments.

 


Support

Ask our DWS experts about special applications such as dispersion rheology or rheology under extreme conditions (e.g. high temperature or pressure) at .