The conditional probabilities approach to the copolymerization process of two or more monomer species

This article completes previous work which addressed the propagation step of a copolymerization process using the conditional probabilities approach. In the present article the theory is extended to arbitrary values nu and n of a copolymerization process, in which nu is the number of monomers in the feed and n the number of monomers along the growing chain which influence the conditional probability for adding one further monomer of a defined monomer species. First, a system of linear equations to be solved as functions of the conditional probabilities is given, followed by the description-in general terms-of the procedures to be followed to estimate the mean composition of the multimonomer chains, the mean-length of the sequences of the various monomers along the chain, and the mean-number of transitions from sequences of one species to sequences of other species. These general considerations are then applied to the specific case of terpolymerization in the terminal model, that is nu = 3 and n = 1, for which case detailed relationships are given. In a following section the parameters of the conditional probabilities approach are related to the more usual parameters of copolymerization theory, ie kinetic constants, concentration of active centres and concentration of monomers in the feed. The heat of copolymerization problem, addressed in the previous article, is not considered here. General considerations are discussed with respect to other work in the field.