Fourier Transform Rheology as an innovative morphological characterization technique for the emulsion volume average...

Area of Science:

• Rheology
• Colloid and Surface Science
• Materials Science

Background:

• Emulsion characterization is crucial for commercial applications.
• Fourier Transform Rheology (FTR) offers advanced methods for analyzing emulsion properties.
• Understanding nonlinear rheological behavior is key for complex fluid systems.

Purpose of the Study:

• To investigate the impact of polydispersity and high volume fraction on emulsion nonlinear rheology.
• To extend the application of Large Amplitude Oscillatory Shear (LAOS) measurements for emulsion characterization.
• To correlate nonlinear rheological parameters with emulsion microstructure, including droplet size and distribution.

Main Methods:

• Utilized Fourier Transform Rheology, specifically Large Amplitude Oscillatory Shear (LAOS) measurements.
• Characterized emulsions by volume average radius and polydispersity index.
• Analyzed nonlinear mechanical emulsion value E(0) and higher harmonic ratios I(5/3) and I(7/5).

Main Results:

• Demonstrated that nonlinear rheological parameters correlate with emulsion droplet size and distribution.
• Showed that higher harmonic ratios I(7/5) provide information on the distribution width.
• Successfully applied LAOS experiments to characterize commercial water-in-oil (w/o) emulsions with high volume fractions.

Conclusions:

• Nonlinear rheology, particularly LAOS, is a powerful tool for characterizing emulsion droplet size and distribution.
• The nonlinear mechanical emulsion value E(0) is a useful metric for emulsion characterization.
• FTR provides valuable insights into the microstructure of highly filled emulsion systems.