When a Newtonian
bubble ruptures, the film retraction dynamics
is controlled by the interplay of surface, inertial, and viscous forces.
In case a viscoelastic liquid is considered, the scenario is enriched
by the appearance of a new significant contribution, namely, the elastic
force. In this paper, we investigate experimentally the retraction
of viscoelastic bubbles inflated at different blowing rates, showing
that the amount of elastic energy stored by the liquid film enclosing
the bubble depends on the inflation history and in turn affects the
velocity of film retraction when the bubble is punctured. Several
viscoelastic liquids are considered. We also perform direct numerical
simulations to support the experimental findings. Finally, we develop
a simple heuristic model able to interpret the physical mechanism
underlying the process