Nick Hawkins will be presenting at the forthcoming Thermal Methods Group meeting at NPL on the 9th and 10th November. Details on the meeting can be seen here
The talk will focus on innovative applications possible in rheological measurements using the LS Instruments Rheolab III The following is an abstract from the presentation:
Diffusing Wave Spectroscopy (DWS) – Taking the strain out of rheology.
Diffusing Wave Spectroscopy is a light scattering technique that can be used to measure the rheological properties of a wide range of soft materials (Emulsions, hydrogels, colloids, foodstuffs, creams, lotions for example) whilst contained statically in a sealed cuvette. Measurements can be made between 4°C – 100°C with a frequency scan (typically between 1 Hz – 10 MHz) taking less than a minute. It is therefore an ideal technique for measuring changes in the viscoelastic properties of materials that change quickly over time (for example crosslinking of Hydrogels).
No strain is applied to the sample as with typical mechanical rheometers ensuring that measurements are always performed within the Linear Viscoelastic region. Furthermore, samples can be measured, stored and re-evaluated over time to identify any changes in structural properties. Small sample volumes are required for measurement (typically 400µL) which makes it an ideal technique for testing where there is limited sample availability.
This presentation will introduce the technique of DWS and show some typical examples for where it has been used successfully to characterise the Rheological properties of soft matter.
If you’d like to know more then contact us now or see Nick at the event.