Kinetic Criteria of Living Polymerization

The kinetic scheme of living, reversible ROP can also encompass-apart from initiation (Equation 1.27a) and propagation (Equation 1.27b)-additional reversible reactions, such as segmental exchange (Equation 1.27c) or temporary termination (Equation 1.27d). 

In spite of the side reactions (Equations 1.27c and d) that may take place, the polymerization described by Equation 1.27 meets the criteria of the living process, provided that the activation is sufficiently fast (i.e. k, kp[M]) since, under this condition, the system comprises exclusively macromolecules that are capable of growth. 

In the case of rapid initiation and reversible propagation being the only reactions in the polymerizing system, and proceeding only with one kind of active center, the expression for the polymerization rate (assuming the independence of kp on DPn) reads  

Integration of Equation 1.28 leads to the well-recognized serrulogarithmic dependence of monomer concentration on polymerization time  

For the strained three- and four-membered monomers, [Mje, 0. However, the need to insert [Mje, into Equation 1.29 for the higher-membered monomers seems self-evident. Moreover, the [Mje, value determined under the exact polymerization conditions must be used since, in the past serious errors have been made in the 

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