Models allowing for the deviations from ideality

The Flory principle, whose validity has been established for a wide range of polyreactions, is rather good approximation for the description of the kinetics of many processes of polymer obtaining. Flowever, a considerable body of experimental results is currently available concerning a number of macromolecular reactions where this principle is deliberately violated. Possible reasons for the deviations from this principle can be attributed to the short- or long-range effects (Kuchanov, 2000). 

Among the first of them are the so-called substitution effects due to steric, induction, catalytic, or some other types of influence of the reacted active centers on the reactivity of neighboring unreacted centers. In order to take account of such short-range effects it has been suggested (Kuchanov, 1978) to use under mathematical modeling an extended Flory principle. In line with this principle, the reactivity of any active center of a molecule is supposed to be controlled exclusively by local chemical structure of the 

---