The name is absent

(a)

2

О --------------------------I__________________________ɪ__________________________ɪ__________________________

0   12   3   4

z∕σ

Figure 7.4: (a) Total segment density profiles of the confined 3-arm star (m = 5) poly-
mer fluid at η_aυg = 0.1 (o), 0.2 (□), and 0.3 (Δ) from modified iSAFT (solid curves),
DFT approach of Malijevsky et. al. [268] (dashed curves), and molecular simulations [264]
(symbols), (b) Comparison of the total segment density profiles of the confined 21-segment
linear (dashed curve) and 4-arm star (solid curve) polymer fluids at η_aυg = 0.3. Symbols
are the molecular simulation results for the star polymer fluid from Yethiraj and Hall [265].

Figure 7.4b compares the total segment density profiles of the 21-segment linear
and 4-arm star (m = 5) polymer fluids confined between the two flat hard surfaces
separated by H = 10 σ, at the same packing fraction. The segment densities are
normalized by their average values in the confinement. The profiles are similar for
both star and linear polymer fluids with slight difference in their contact densities.
The contact density is related to the pressure of the fluid at density equal to its bulk
density in the confined space, βP{pbuik) — -Wp(O). Hence, the compressibility factor
(Z — βP∕Pbuik) ɑf bulk star and linear polymer fluids with same number of segments
in the chain are only slightly different at a given fluid density. This suggests that

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