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understood from the chemical compositions
of the different eluting fractions. Sample
EP1 has the highest average ethylene con-
tent (49%) while sample EP3 has the
lowest average ethylene content (26%),
see Table 1. The results in Figure 7 indicate
the same trend: in EP1 the first eluting
(propylene-rich) fraction shows a peak area
ratio of 0.63-0.5 while for EP3 this ratio is
higher with 0.72-0.5. This indicates that the
propylene content of this fraction is higher
for sample EP3. In addition to the higher
propylene content, the area of this peak is
higher as compared to EP1. This is a clear
proof that the average propylene content of
EP3 is higher as compared to EP1.
The aim of forthcoming investigations is
the exact calibration of the FTIR system for
a strict quantitative analysis of the ethylene
content of the EP copolymers. To achieve
this goal NMR data of model EP copoly-
mers will be correlated with corresponding
FTIR bands for PP and PE. By using a fully
calibrated system, absolute chemical com-
position values of amorphous EP copoly-
mers can be obtained and the chemical
composition distribution of these copoly-
mers can be described.
Williams, S. O'Donohue and R. Linz (Polymer
Laboratories, Church Stretton, England) in
designing, building and adjusting the high-
temperature gradient HPLC system. We thank
BASELL Polyolefine GmbH for supplying the
EP copolymers. The financial support of the
work by BASELL Polyolefine GmbH (Frank-
furt, Germany) and BMBF (grant No.
03C035YA) is highly appreciated.
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