  We propose a coarse-grained model to investigate stress relaxation in
star-polymer networks induced by dynamic bond exchange processes. We show how
the swapping mechanism, once activated, allows the network to reconfigure,
exploring distinct topological configurations, all of them characterised by
complete extent of reaction. Our results reveal the important role played by
topological defects in mediating the exchange reaction and speeding up stress
relaxation. The model provides a representation of the dynamics in vitrimers, a
new class of polymers characterized by bond swap mechanisms which preserve the
total number of bonds, as well as in other bond-exchange materials.
