Phenol formaldehyde (P-F) resins are thermoplastic materials made with an excess
of phenol in an acid catalyzed reaction with formaldehyde. P-F resins are commonly
used as precursors to varnishes and other surface finish products.
PolarGel-M GPC columns are packed with low swell,
macroporous copolymer beads that have a surface of
balanced polarity, comprizing hydrophobic and hydrophilic
components. These allow PolarGel-M to be used in the
analysis of high polarity polymers that are insoluble in water
to give a more accurate representation of the molecular
weight distribution of the polymer. If these polar polymers
were to be analyzed with traditional styrene/divinyl benzene
columns, interactions would cause artifacts in the peak
shape and longer retention times, which would translate into
apparently much lower molecular weight averages.
Two types of phenol-formaldehyde resin were analyzed to
obtain an indication of differences in molecular weight, if
any. The samples were made up in 0.2 % (w/v) DMF, with
0.1 % LiBr added to reduce sample aggregation, and injected
without further treatment.
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