The name is absent

The interfacial region in homopolymer blends and the mesophases in diblock
copolymer melts are examples of inhomogeneous polymer systems, which are charac-
terized by non-uniformity in density with respect to spatial co-ordinates (on the order
of molecular diameter), despite being in a state of equilibrium. To better understand
this concept, a simpler example of a polymeric fluid adsorbed on to a (flat) planar
surface, is considered. Since the surface is planar, the inhomogeneity is only in one
dimension, which is normal to the surface. Figure 1.2 shows the I-D microstructure
in terms of the total segment density (p(z)) of the polymeric fluid as a function of
the normal distance (z) away form the wall. Note that the normal distance is scaled
by the segment diameter (σ) and the total segment density is scaled by its value in
the bulk fluid (‰⅛), far away from the surface. The figure shows an enhancement
in the total segment density at the surface, oscillations near the surface and finally a
flat uniform profile away from the surface. The uniform region defines the bulk fluid
which in equilibrium with the inhomogeneous fluid.

Many polymer systems are inhomogeneous, often encountered in biological, inter-
facial, and confined systems. Self-assembled lipid bilayers and micelles are classical
examples, which are ubiquitous in all biological systems. Interfacial systems are of
great industrial significance in areas like paints and coatings (polymer adsorption),
detergents and shampoos (surfactants), food production (emulsions and colloids),
pharmaceuticals (suspensions), lithographic templates for semiconductors (copoly-
mer films), and microfluidic devices (hydrophobic films). Confined systems are of

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