The name is absent

order. The microstructure of these mesophases depend mainly depend upon relative
compositions of the A and B blocks in the copolymer and the degree of incompatibil-
ity between the two blocks, as shown in fig. 1.1. In the figure, χ parameter quantifies
the degree of incompatibility between the blocks, N is the degree of polymerization
of the copolymer, and f is the ratio of the degree of polymerization of the A block to
that of the B block. As shown in the figure, there is a critical value of the parameter
χN at a particular /, where the order-disorder transition (ODT) takes place. For
example, for / equals to 1/2 (symmetric diblock copolymer), the ODT takes place at
χN ~ 10.5 [49]. The microstructure of the mesophases vary from cubic at low degrees
of polymerization of one of the blocks to lamellar for symmetric diblock copolymers.

Figure 1.1: Schematic of the phase diagram and microstructures of diblock copolymers.
Figure from http://www.physics.nyu.edu/pine/research/nanocopoly.html

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