Final Thesis

Characterization of surface hydrophobicity of microparticles

Key Info

Basic Information

Soft Matter Process Engineering
Masterthesis / Bachelorthesis
Focus/Key Topic:


The nature of particle surfaces is of great importance in process engineering since many chemical and biochemical processes take place on surfaces. Hydrophobicity is a very important surface property in aqueous media that is difficult to characterize, especially for micro- and nanoparticles. It is based on the energetics of water dipoles and hydrogen bonds and has a great influence on the wettability and hydration of particle surfaces.

Our group is developing a method that provides the possibility to rank microparticles with regard to their hydrophobicity. For this purpose, an organic solvent is added to an aqueous phase containing a defined concentration of microparticles. Then, according to the mixer-settler concept, the two phases are first mixed and later separated. Afterwards microparticle concentrations in the aqueous phase are determined to calculate partition coefficients.

In the context of this work:

  • suitable synthetic particles with defined surface properties are selected and their partition coefficients with butanol, hexanol, octanol and decanol are determined,
  • the mixer settler experiments are carried out at 5 different temperatures, since the entropic part of the hydrophobic effect is temperature dependent,
  • a hydrophobicity series is to be created from the results of the tests on the basis of the particles used,
  • casein-based microparticles should be classified in this series.

The work includes literature research, experimental lab work, as well as the interpretation of the collected data.