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satisfactory. Often, they are rather primitive and cannot explain the whole diversity
of processes in complex dynamic systems. As a result, a number of new terms were
introduced in the literature with the intention to better define or supplement
particular aspects of this complex phenomenon. Besides the already mentioned
term “self-assembly,” further frequently used terms include “stigmergy,” “conser-
vative self-organization,” “dissipative self-organization,” etc.
For all these reasons, before considering in detail the essence of self-
organization and the mechanisms of the processes responsible for introducing
order into the system, let us turn to some concrete examples of scientific and social
problems.
6.2 Self-Organization Processes and Their Properties
1. Let us pour in a vessel two solutions containing silver nitrate and sodium
chloride. The Ag+ ion is known to be an indicator of the content of halogen ions.
Therefore, after mixing these two solutions a thick white silver chloride precipitate
drops out.
2. Suppose that a polymer is being synthesized based on two different blocks,
oligomers A and B, such that these oligomers consistently alternate in the polymer
chain. This process is called block copolymerization. As a result, microphase
separation structures arise in the synthesized polymer. These structures vary
(Fig.
6.1
) depending both on the relative content of oligomers A and B in the
synthesized polymer and on the Flory-Huggins value (
). It is determined by the
nature of the interaction between the oligomers and by the temperature. Raising the
temperature leads to a decrease in the parameter
χ
χ
and to disappearance of
microphase separation.
Fig. 6.1 Microphase separation structures in diblock copolymers as a function of the relative
content of blocks in the polymer
