The name is absent

(inhomogeneous) polymeric fluids. Another aspect while modeling inhomogeneous
polymers, can be explained in terms of the example depicted in fig. 1.2. The range
of oscillations in the total segment density profile is about 3-6 segment diameters,
which is considerably smaller than the size of the polymer molecule. Hence, it is clear
that a polymer molecule could at the same time be in the inhomogeneous as well as
the bulk region. So the very notion of ‘local’ molecular density in the inhomogeneous
region loses its significance. Since, bulk polymer theories analyze the system in terms
of molecular density, any extension of their arguments to inhomogeneous systems
cannot be expected to paint an accurate picture.

Short-range variations in the local density, along with the long-range structure,
plays an important role in determining the macroscopic properties of the inhomoge-
neous polymers. For example, thin films of confined symmetric diblock copolymer
form different lamellar phases (parallel∕perpendicular to the confining surfaces with
different number of lamella) between the two confining surfaces. The total segment
density profiles of these lamellar phases show variations in the densities near to the
confining surfaces. These variations influence the relative stability of the different
lamellar morphologies [50]. Hence, to successfully model inhomogeneous polymer
systems, the model must incorporate molecular features on all length scales, and yet
remain computationally tractable.

Apart from modeling, fundamental challenge lies in understanding the new physics
that emerges from finite-size effects, varying dimensionality, and surface forces. The

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