3D Fluorescent Mapping of Invisible Molecular Damage after Cavi-tation in Hydrogen Exposed Elastomers

Xavier P. Morelle; Gabriel E. Sanoja; Sylvie Castagnet; Costantino Creton

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arXiv · 2101.00709

3D Fluorescent Mapping of Invisible Molecular Damage after Cavi-tation in Hydrogen Exposed Elastomers

Xavier P. Morelle·Gabriel E. Sanoja·Sylvie Castagnet·Costantino Creton

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Abstract

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.

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Xavier P. Morelle, Gabriel E. Sanoja, Sylvie Castagnet, Costantino Creton. 2021-01-03. 3D Fluorescent Mapping of Invisible Molecular Damage after Cavi-tation in Hydrogen Exposed Elastomers. https://arxiv.org/abs/2101.00709

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