The name is absent

averaged out by contact with increasingly large numbers of surrounding segments.

This completes the general formalism of SCFT where the polymer molecules are
represented as space curves which are modeled as continuous Gaussian chains. The
first step is defining the interactions between the molecules. The hard-core repulsions
are crudely imposed by the incompressibility approximation while the long-range at-
tractions are defined in terms of the Flory-Huggins χ parameter. A particle-to-field
transformation follows which decouples the interactions between the molecules, re-
placing them with the interactions between each molecule and external fields. These
fields are then obtained self-consistently with the average segment densities (mi-
crostructure) by imposing the mean-field approximation.

8.4 Approximations in SCFT

Previous sections introduces the formalism of SCFT. This section concludes the
chapter by recapping the approximations in SCFT

• The polymer molecules are modeled as continuous Gaussian curves. This coarse-
graining suppresses all the effects related to the atomic details. Hence, the
segment level information of the polymer structure and short-range effects are
lost in this coarse-grained approach.

• The short-range repulsive interactions are crudely approximated by the incom-
pressibility approximation. The incompressibility approximation neglects the

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