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We study the recombination kinetics and stress relaxation in a generic reversible polymer model, which is believed to resemble a wormlike micellar system. We find evidence that, at high concentrations, the recombination kinetics in this model cannot be described by a mean-field approach, but is diffusion controlled and dominated by self-recombination events. We observe that the long time stress relaxation of unentangled chains is proportional to 1/sqrt(t) exp(-t/tau_relax), with a relaxation time given by tau_relax = t_h^(2/3) tau_L^(1/3), where t_h is the average diffusion time to a different chain end, and tau_L is the characteristic relaxation time of a system of ``dead'' polymers of length equal to the average micellar length. A recombination activation barrier is needed to drive the system towards mean-field behaviour. This, in its turn, is often required in order to realistically model the rheology and dynamics of wormlike micelles. |