  When moist air meets a cold surface, it creates a breath figure characterized
by numerous small droplets. The central question is how the vapor flux is
distributed between the growth of previously condensed drops and the nucleation
of new ones. Here, we investigate the nucleation, growth, and coalescence of
droplets on soft crosslinked polymer networks. The number of droplets initially
remains constant, until drops start to coarsen according to a universal law;
both phenomena are explained via the formation of a saturated boundary layer.
Although nucleation occurs at a scale where the polymer network resembles a
melt, we quantitatively unveil an algebraic sensitivity of the number of
droplets on the substrate elasticity. Our findings suggest that nucleation
follows a surprisingly low-energy pathway, influenced by the degree of
crosslinking. Consequently, breath figures offer a macroscopic approach to
probe the molecular characteristics of the polymer interface.
