Molecular and colloid chemical characterization

Aqueous size exclusion chromatography (SEC)

 

Analyte

  • Polyelectrolytes as well as nonionic water soluble polymers and polysaccharides
  • Sample mass: ~ 100 mg
  • Molar mass range: 103 - 108 g/mol

 

Equipment

  • Eluent: aqueous salt solution (if required with organic co-eluent)
    e.g. 0.2 M Na2SO4+1% HAc
  • Detection: refractometer, UV-detector, viscometer, multi angle laser light scattering (MALLS)
  • Special feature: column tempering, Fraction collector

 

Targets

  • Conventional calibration with Dextran, Pullulan, polyvinylpyridinium and polystyrene sulfonic acid
  • average molar masses (Mw , Mn); polydispersity index D
  • Universal calibration by means of viscometry
  • intrinsic viscosity [ η ]; Mw; Mn; D
  • Absolute molar mass determination by means of static light scattering
  • molar mass weight average MW, average radius of gyration <Rgz>, Mn, D
  • Additionally, in special cases an analysis of copolymer and structure composition can be performed.

 

Application

  • Graft copolymerization of cationic monomers on starch (→ PDF)
  • Enzymatic synthesis of high molecular Inulin (→ PDF)
  • Derivatization of starch (→ PDF)

 

Comparative and Complementary Methods