5 - Max-Planck-Institut für Kohlenforschung

42
Synthetic Organic Chemistry - G. Fink
were observed. We were able to correlate this initial polymerization activity of
individual grains with the cocatalyst MAO loading and distribution on the catalyst
carrier by means of microanalytical techniques (see figure). Only a fraction of all
particles reveal an even aluminum distribution throughout the particle, others show up
with a shell like aluminum enrichment on the outer particle surface.
As second theme in this
research area we focused on
videomicroscopy for direct
measurement of polymer and
particle growth in gas phase
polymerization under indus-
trial process conditions. This
technique enables the
simultaneous detection of the
individual growth of a large
number of catalyst particles.
In addition to visualizing
polymer growth and the
replication of catalyst
morphology, we were able to
obtain detailed information
about the polymerization
kinetics of numerous catalyst
particles, which act as
discrete microreactors. A
detailed description of the
experimental setup is given in
the report for the period 2000-
2001, p.169-170.
As example the figure shows
the in situ observation of the
ethylene polymerization with
a solid Zirconocene / MAO /
SiO2 catalyst.
The figure on the left shows a
superposition of the detected