The name is absent

concentration diagram. The two phase region predicted by the new EOS is broader
than PC-SAFT prediction (PC-SAFT parameters for HDPE are taken from [79] ) and
the phase envelope is in good agreement with the experimental data. The phase
behavior of the HDPE-n-hexane system predicted from the new EOS is shown in
figure 2.lib. The phase behavior is compared with the experimental data and PC-
SAFT predictions. At low polymer concentrations (Wp^ ≤ 10%), both EOS predict
similar phase behavior. At higher polymer concentrations the PC-SAFT pressure-
composition curve becomes steeper. The new EOS predicts a broader two phase
region.

In both the previous cases the polymer was assumed to be monodisperse. Kiran
et. al. [93] studied the effect of polydispersity on the demixing pressure of polyethy-
lene in n-pentane. The PE sample used for the analysis had a M_w = 121kg∕mol and a
polydispersity index of 4.32. The molecular weight distribution of the sample was de-
termined by gel-permeation chromatography (GPC) analysis. Based on the analysis
the polymer was characterized by 10 pseudo-components (see table 2.4) for our cal-
culations. The phase envelope predicted from the new EOS for this HDPE-n-pentane
system is shown in figure 2.12a. The results are compared with the experimental data
and the prediction from PC-SAFT. The new EOS shows significant improvement in
the shape of the cloud point curve compared to PC-SAFT. The pressure composition
slope is nearly the same as what is seen from the experimental data, hence the new
EOS predicts the two phase region more accurately.

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