Physico-Chemical Transformations and Equilibria

A physico-chemical transfonnation of a system is the modifieation of the nature of its components under the influenee of external stresses. 

A component is characterized by its chemical nature and by the phase to which it belongs. We can distinguish two types of physico-chemical 

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Equilibria between various forms of living centres were treated in Chap. 5, Sect. 8.1. Equilibria of similar character control the arrangement and reactivity of all ionic centres. When polymerization-inactive structures participate in the equilibria, the number of active centres is reduced by the equilibrium amount of inactive forms. This phenomenon is usually not considered as termination the unreactive particles are treated as dormant. In the course of polymerization, however, the physico-chemical parameters of the system change as a function of the monomer-polymer transformation. Changes in permittivity, viscosity and the amount of polymer can cause shifts in ionization and dissociation equilibria. The kinetic manifestations of such changes are identical with the occurrence of termination. 

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