The development in the preceding paper is extended to the stepwise polymerization of polyfunctional monomers bearing A and B coreactive groups, a monomer being able to carry together A and B functional groups. The molecular parameters characterizing the post-gel properties of such macromolecular networks are derived quite as directly as in the order I systems and have expressions which are morphologically analogous.

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The molecular parameters of macromolecular networks made by stepwise polymerization of polyfunctional monomers bearing identical reactive groups are established from the calculation of the probability that a functional group leads to a finite chain. The determination of this finite chain probability as a function of reaction extent and characteristics of the system is computed directly from very simple implicit equations. Thus, sol fraction, cross-link density, effective network chains numbers, dangling trees numbers, and cycle rank are derived easily in very general systems.

A new method, using the propagation expectation defined by Case, is presented to compute directly and simply the general expressions of average molecular weights for condensation polymerisation of polyfunctional monomers. In particular, the weight average molecular weight in systems composed of monomers endowed with both A and B coreactive functional groups is derived.

The method of Case is used with the Flory‐Stockmayer gelation criterion to derive a critical transition equation for polycondensation of multifunctional reactants bearing coreactive functional groups of two species A and B, where the B groups may be of unequal intrinsic reactivity. Systems of the types R(A)2/R′(B)4 and R(A)2/R′(B)4/R′′(B)2 are considered with the B groups divided into two classes characterized by a reactivity ratio in the range 0.1 to 10. If the reactivities are sufficiently different the polymerization can be regarded as a multistage process. Intramolecular reactions are not considered.