Molecular and colloid chemical characterization

Analyses for polymers, polysaccharides and nanoparticles

Gel Permeation Chromatography

Membrane Osmometry

Static Light Scattering

Particle Size Analysis

Your Contact Persons

 

Our experts look forward to answering your questions and supporting your projects.

Gel Permeation Chromatography

Analyte

  • polyelectrolytes as well as non-ionic water-soluble polymers and polysaccharides
    • molar mass range: 102 - 108 g/mol
  • in organic solvents
    soluble polymers
    • molar mass range: 102 - 107 g/mol

Equipment

  • eluents
    aqueous: salt solutions, e.g. with organic coeluents, e.g. 0.2 M Na2SO4+1% HAc
    organic: Tetrahydrofuran (THF), Chloroform (TCM), Dichlormethane (DCM), Hexafluorisopropanol (HFIP), Toluene, Dimethylformamide (DMF), Dimethylacetamide (DMAc), Dimethyl sulfoxide (DMSO), e.g. with added salt, e.g. NaNO3, LiBr, CF3COONa, more on request
  • detectors
    RI refractometer, UV detector,
    Evaporative light scattering detector ELSD
    combination with viscometer or multi-angle light scattering (MALS)
  • special features: column temperature control, fragment collector

Target

  • determination of molar mass averages (Mn, MW) and molar mass distribution (Polydispersity index D)
  • relatively
    calibration with dextran, pullulan, polyvinylpyridine, polystyrene sulfonic acid, PS, PMMA, PEG, PEO
  • universal calibration, combination with viscometry
  • absolute
    GPC-MALS (combination with multi-angle light scattering)

Application
and Download

  • molar mass analysis of synthetic
    polymers and copolymers
  • molar mass analysis of natural and bio-based polymers (e.g. starch, cellulose, lignin, proteins, PLA, PHB)
  • reaction monitoring of polymer syntheses
  • tracking of degradation reactions, recycling processes and aging

Methods of comparison and supplementation

  • membrane osmometry (Mn)
  • static light scattering (MW; RZ; A2)
  • dynamic light scattering (dH)
  • differential refractometry (dn/dc)

Membrane Osmometry

Analyte

  • polymers or nanoparticles that are soluble or dispersible in aqueous media or organic solvents
  • required sample quantity: 100-500 mg
  • molar mass range: 104 - 105

Equipment

  • GONOTEC OSMOMAT 090 membrane osmometer
  • membranes: cellulose triacetate (cut-off 5,000, 10,000 and 20,000 g/mol), regenerated cellulose (cut-off 20,000 g/mol)
  • solvents: water and aqueous salt solutions as well as organic solvents like tetrahydrofuran, toluene, chloroform etc.

Target

  • measurement of the osmotic pressure p as a function of the polymer concentration and extrapolation of the reduced osmotic pressure to the concentration zero
    • numerical average molar mass Mn and 2nd virial coefficient A2

Application
and Download

  • molecular characterization of
    reference materials from Poly-DADMAC

Methods of comparison and supplementation

  • aqueous size exclusion chromatography (Mn; MW; D)
  • static light scattering (MW; RZ; A2
  • differential refractometry (dn/dc)
  • dynamic light scattering (dH)

Your Contact Person

Static Light Scattering

Analyte

  • synthetic and natural polymers in dilute solutions

Equipment

  • multi-angle light scatterer from Wyatt, model DAWN NEON and DAWN Heleos II, computer controlled
  • wavelength of the laser: 658 nm

Target

  • determination on molecular data of synthetic and natural polymers in dilute solutions
  • weight average of molar mass MW
  • numerical average of the radius of gyration RG
  • analysis of the behavior of synthetic and natural polymers in concentrated solutions
  • structural analytics of polymers
  • determination of relationships between structure and properties
  • investigation of association and aggregation processes

Your Contact Person

Particle Size Analysis

Analyte

  • polymers, colloids and nanoparticles in aqueous and organic solutions, powder
  • particle sizes
  • size range: 0.1 nm - 2000 µm
  • concentration range: 0.001 - 40 %

Equipment

  • Delsa Nano +C (Beckman Coulter)
  • Zetasizer Nano (Malvern)
  • Mastersizer X (Malvern)
  • Particle sizer LS 13320 XR (Beckman Coulter)
  • Wyatt DynaPro NanoStar

Target

  • determination of diffusion coefficient and hydrodynamic radius by means of dynamic light scattering
  • mathematical determination of particle sizes by cumulate, contin, Marquardt and NNLS methods
  • determination of intensity, volume and number distribution functions
  • particle size distribution of nano- and microparticles

Application and Download

  • determination of the hydrodynamic radius of polymers and polyelectrolytes as a function of solvent, electrolyte content and pH value
  • derivations concerning the property profile of polymer dispersions (viscosity, sedimentation / flotation etc.)
  • investigation of symplex formation between cationic starch and anionic polyelectrolytes

Methods of comparison and supplementation

  • electron microscopy

Your Contact Persons

Jens Buller

Contact Press / Media

Dr. Jens Buller

Static light scattering | Particle size analysis

Fraunhofer IAP
Geiselbergstraße 69
14469 Potsdam

Phone +49 331 568-1478

Kathrin Geßner

Contact Press / Media

Dipl.-Ing. (FH) Kathrin Geßner

Particle size analysis

Geiselbergstraße 69
14476 Potsdam-Golm

Phone +49 331 568-1415

Hendrik Wetzel

Contact Press / Media

Dr. Hendrik Wetzel

Gel permeation chromatography

Fraunhofer IAP
Geiselbergstraße 69
14476 Potsdam

Phone +49 331 568-1604

Erik Wischerhoff

Contact Press / Media

Dr. Erik Wischerhoff

Membrane osmometry

Fraunhofer IAP
Geiselbergstraße 69
14476 Potsdam

Phone +49 331 568-1508