The name is absent

vent molecules are parameterized with a Flory ^cχ^, parameter. The solution is assumed
to be locally incompressible.

In the canonical ensemble, the solution consists of a mixture of ng solvent molecules
and np polymer molecules in a system of fixed volume V and temperature T. Each
polymer chain occupies a volume ι⅛N, where ⅝ is the volume of a statistical seg-
ment and its conformational properties are described by the continuous Gaussian
chain model. The solvent molecules also occupy the same volume, t⅛. Thus the total
number density of the solution, p₀ = 1∕∙vq. While, the microscopic densities of the
polymer segments and solvent are defined, respectively, by

Pp(γ) = ∑ / ^{ds δ}(^r ~                        (⁸∙²⁵)

j=ι ^Jo

ns

⅞(^r) = ∑<*(^r~^rj)∙                     (⁸∙²⁶)

J=I

By analogy with the Flory-Huggins lattice theory, the interaction energy between the
solvent molecules and the polymer segments is described by

∕3t∕ι[r^ns+ⁿ^] = V_θχ_ps [ ⅛(r)⅛(r)               (8.27)

This Flory parameter χps describes the energetic strength of local contacts between
solvent molecules and polymer segments, relative to solvent-solvent and polymer-

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