1.1 This International Standard specifies chromatographic
methods for the Separation of phenolic resins
into their component compounds. Separation takes
place according to molecular weight and/or polarity.
There are various liquid chromatographic methods:
A: Gel-permeation chromatography
B: High-performance
polar columns
Ce l-ligh-performance
non-polar columns
liquid chromatography on
liquid chromatography on
lt is possible to separate a phenolic resin into its
components according to molecular size using
method A (gel-permeation chromatography). Whereas
free Phenol and the sum of the dihydroxydiphenylmethanes
(in novolaks) and various
methylolphenols (in resols) are quantitatively separated
in this procedure, high-molecular-weight components
of the resins are only incompletely separated
due to the multitude of isomers.
Methods B and C (high-performance liquid chromatography)
separate the compounds in the resin according
to molecular weig ht and polarity.
Molecular-weight effects predominate on polar stationary
phases (method B), and the effect of polarity
on non-polar stationary phases (method C). These
methods also allow quantitative determination of individual
low-molecular-weight resin components. Because
of the different resin solubilities, method B is
more suitable for novolaks and method C for resols.
1.2 The methods are applicable to phenolic resins
that are soluble in the solvents and solvent blends
used.
1.3 This test is useful for characterization of products
and for research
Diese Norm beschreibt chromatographische Verfahren zur Auftrennung von Phenolharzen in ihre Bestandteile. Die Trennung erfolgt nach relativer Molekularmasse und/oder Polarität. Es gibt verschiedene Verfahren der Flüssigchromatographie: Gelchromatographie, Hochleistungsflüssigchromatographie auf polaren Kolonnen; Hochleistungs-Flüssigchromatographie auf unpolaren Kolonnen. Die Verfahren sind für Phenolharze, die in den verwendeten Lösungsmitteln und Lösungsmittelgemischen löslich sind, anwendbar. Das Verfahren ist zur Charakterisierung von Produkten und für Forschungsarbeiten nützlich.