Elastomer Mechanics of Cross-Linked Linear-Ring Polymer Blends

Zhang, Siteng [University of South Carolina, Columbia, SC (United States)]; O’Connor, Thomas C. [Carnegie Mellon University, Pittsburgh, PA (United States)] (ORCID:0000000293930295); Grest, Gary S. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000252609788); Ge, Ting [University of South Carolina, Columbia, SC (United States)] (ORCID:000000032456732X)

doi:10.1021/acsmacrolett.5c00095

DOE OSTI · 2547071

Elastomer Mechanics of Cross-Linked Linear-Ring Polymer Blends

Zhang, Siteng [University of South Carolina, Columbia, SC (United States)]·O’Connor, Thomas C. [Carnegie Mellon University, Pittsburgh, PA (United States)] (ORCID:0000000293930295)·Grest, Gary S. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000252609788)·Ge, Ting [University of South Carolina, Columbia, SC (United States)] (ORCID:000000032456732X)

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Abstract

Cross-linking a blend of linear and ring polymers creates a new topology-based dual-network elastomer in which the two components differ significantly in their topology. We use molecular simulations and topological analysis to examine key mechanical properties as functions of ring polymer volume fraction Φ R . For Φ R < Φ R *, where the rings begin to overlap, the network shear modulus G and the maximum stretch ratio λ p are weakly dependent on Φ R . For Φ R > Φ R *, entanglements trapped in the network are diluted as the rings overlap, leading to a significant decrease in G and an increase in λ p with increasing Φ R . Here, the peak tensile stress, σ p , exhibits a maximum around Φ R *, indicating an enhancement of network strength due to the stronger cohesion from the entanglements between linear and ring polymers.

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Zhang, Siteng [University of South Carolina, Columbia, SC (United States)], O’Connor, Thomas C. [Carnegie Mellon University, Pittsburgh, PA (United States)] (ORCID:0000000293930295), Grest, Gary S. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000252609788), Ge, Ting [University of South Carolina, Columbia, SC (United States)] (ORCID:000000032456732X). 2025-04-01. Elastomer Mechanics of Cross-Linked Linear-Ring Polymer Blends. https://doi.org/10.1021/acsmacrolett.5c00095

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