This standard describes the determination of the molecular weight distribution, number-average molecular
weight Mn and weight-average molecular weight Mw of polymers that are soluble in water by gel permeation
chromatography (GPC).
This standard is applicable to neutral polymers and polyanions (e.g. polycarboxylates, polysaccharides,
completely saponified polyvinyl alcohols and high-molecular polyethylene oxides). It is not applicable to
polycations (e.g. polyvinytpyrrolidone, polyvinylpyridine, salts of poly(diallyI-N,N-dimethyl-azacyclopentane)
and chitosane.
It is possible that, in spite of the good solubility in the mobile phase and the good repeatability of the
chromatograms obtained, this method cannot be used with certain polymer types because of specific
interactions, such as adsorption, within the sample/eluent/column combination (see also clause 12).
The method is not an absolute one and requires calibration with commercially available unbranched pullulan
standards that have been characterized by independent absolute methods. The results for samples of
polymers other than pullulan are therefore only comparable within groups of samples of the same type.
The conditions specified in this standard are not suitable for the GPC analysis of polymer samples with Mw
values greater than 10~6 g/mol (see Annex C).
No correction methods (e.g. for the elimination of peak broadening) are included in this standard. If absolute
molecular weight values are required, an absolute method, e.g. membrane osmometry for Mn or light
scattering for Mw, shall be used.