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arXiv · 2201.10498

Super-stretchable Elastomer from Cross-linked Ring Polymers

Jiuling Wang·Thomas C. O'Connor·Gary S. Grest·Ting Ge
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Abstract

The stretchability of polymeric materials is critical to many applications such as stretchable electronics and soft robotics, yet the stretchability of conventional cross-linked linear polymers is limited by the entanglements between polymer chains. We show using molecular dynamics simulations that cross-linked ring polymers are significantly more stretchable than cross-linked linear polymers. Compared to linear polymers, the entanglements between ring polymers do not act as effective cross-links. As a result, the stretchability of cross-linked ring polymers is determined by the maximum extension of polymer strands between cross-links, rather than between entanglements as in cross-linked linear polymers. The more compact conformation of ring polymers before deformation also contributes to the increase in stretchability.

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Jiuling Wang, Thomas C. O'Connor, Gary S. Grest, Ting Ge. 2022-01-25. Super-stretchable Elastomer from Cross-linked Ring Polymers. https://doi.org/10.1103/physrevlett.128.237801

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