Perkin-Elmer MultiScope System, User Reference

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78 . MultiScope System Microscope User's Reference
Pyrolysis can be used to remove the fillers. As you heat the sample, the polymer
volatilizes, and the fillers are reduced to ash. The pyrolysis can be accomplished in
any of the following ways:
• Place the polymer in a disposable pipette and seal the large end. When this
end cools, tap the polymer into it, then heat the sample gently.
• The pyrolyzed polymer condenses on the walls of the pipette. The filler is left
behind as ash.
•
Score and break the pipette between the ash and the pyrolysate. Add a drop of
solvent to the pyrolysate to wash it on to a salt plate.
• If the amount of sample is small, use a capillary tube instead of a disposable
pipette for the above procedure.
•
Use a microbrush to pyrolyze micro amounts. Seal the end that is away from
the brush fibers and tap the sample particle into this end then heat it gently
with a microtorch. After pyrolysis, break off and discard the end of the tube
that contains the ash. While holding the fibers of the brush against the salt
plate, add a drop of solvent to the broken end. Allow the solvent containing the
pyrolysate to flow into the fibers. When it evaporates, the pyrolysate is left on
the salt plate for analysis.
Particles
Crushing
Samples such as large particles that cannot be sliced can often be crushed to thin
them. This can be done in various ways:
• If the sample is small, crush it with the roller end of the roller knife.
•
If the sample is larger, use a pestle and mortar.