  Elastomers saturated with gas at high pressure suffer from cavity nucleation,
inflation, and deflation upon rapid or explosive de-compression. Although this
process often results in undetectable changes in appearance, it causes internal
damage, hampers func-tionality (e.g., permeability), and shortens lifetime.
Here, we tag a model poly(ethyl acrylate) elastomer with {\pi}-extended
anthracene-maleimide adducts that fluoresce upon polymer chain scission, and
map in 3D the internal damage present after a cycle of gas satu-ration and
rapid decompression. Interestingly, we observe that each cavity observable
during the decompression results in a dam-aged region, the shape of which
reveals a fracture locus of randomly oriented penny-shape cracks (i.e., with a
flower-like morpholo-gy) that contain crack arrest lines. Thus, cavity growth
likely proceeds discontinuously (i.e., non-steadily) through the stable and
unstable fracture of numerous 2D crack planes. This non-destructive methodology
to visualize in 3D molecular damage in polymer networks is novel and serves to
understand how fracture occurs under complex 3D loads, predict mechanical aging
of pristine look-ing elastomers, and holds potential to optimize
cavitation-resistant materials.
