Molecular and colloid chemical characterization

Particle size analysis

Analyte

  • Polymers, colloids and nanoparticles in solution (aqueous and organic solvent
  • Particle size distribution
  • Size range: 0.1 nm – 2000 µm
  • Concentration range: 0.001 – 40 %

 

Equipment

  • Delsa Nano +C (Beckman Coulter)
  • Zetasizer Nano (Malvern)
  • Zetamaster S (Malvern)
  • BI-90 (Brookhaven)
  • Mastersizer X (Malvern)
  • Particle Size Analyzer LS 13320 (Beckman Coulter)
  • AS 200, Fa. Retsch, Dry- und Wetsieving

 

Evaluation methods and targets

  • Determination of the diffusion coefficient and hydrodynamic radius by dynamic light scattering
  • Mathematically determination of the particle size with different methods: Cumulant, Contin, Marquardt and NNLS
  • The Calculation of Intensity-, Volume- and Numberdistributions

 

Application examples

  • Determination of hydrodynamic radius of polymers and polyelectrolytes with dependency on the solvent, electrolyte content and pH
  • Investigation about the simplex formation between cationic starches and anionic polyelectrolytes
  • Conclusions about the property spectrum of polymer dispersions (rheological behaviour, sedimentation / flotation etc.)

 

Measuring principle

  • R.H.Müller / R.Schumann, Teilchengrößenmessung in der Laborpraxis, apv-Paperback, Band 38, Wiss.Verlagsgesellschaft Stuttgart, 1996
  • Untersuchungen bezüglich der Symplexbildung zwischen kationischer Stärke und anionischen Polyelektrolyten (→ PDF)

 

Comparative and additional methods

  • Analytical Ultracentrifuge
  • FFF chromatography
  • Electron microscopy