Polymerization without Transfer and with One Active Species

Polymerization without Transfer and with One Active Species 

Polymerization to equilibrium occurs without termination or transfer and with only one kinetic species. When polymerization begins, all the growing ends P should already exist (infinitely fast start reaction). This case is found, for example, in the polymerization of lauryl lactam, 

NH—(CH2)ii—CO, with amines or carboxylic acids as initiators. The monomer is consumed in the propagation reaction according to -d[M]/dt = kp[M] [P ] and reformed by the depolymerization reaction according to d [M]/dt = [P ]. Thus, overall for the decrease of monomer 

The equilibrium constant is given by K = kp/k p. Furthermore, at an infinite degree of polymerization, according to equation (16-30), the equilibrium constant is K = 1/[M] . Equation (18-57) thereby becomes 

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