Crosslinker energy landscape effects on dynamic mechanical properties of ideal polymer hydrogels

TL;DR

This study uses coarse-grained molecular dynamics to explore how the energy landscape of reversible crosslinkers influences the viscosity and mechanical behavior of ideal polymer hydrogels, providing insights into network deformation mechanisms.

Contribution

It demonstrates the impact of crosslinker energy potential on hydrogel viscosity and structural rearrangements, offering new design principles for improved polymer network performance.

Findings

Stronger crosslinker energy potential increases network viscosity.

Network defects correlate with higher viscosity.

Energy landscape influences deformation mechanisms.

Abstract

Reversible crosslinkers can enable several desirable mechanical properties, such as improved toughness and self-healing, when incorporated in polymer networks for bioengineering and structural applications. In this work, we performed coarse-grained molecular dynamics to investigate the effect of the energy landscape of reversible crosslinkers on the dynamic mechanical properties of crosslinked polymer network hydrogels. We report that, for an ideal network, the energy potential of the crosslinker interaction drives the viscosity of the network, where a stronger potential results in a higher viscosity. Additional topographical analyses reveal a mechanistic understanding of the structural rearrangement of the network as it deforms and indicate that as the number of defects increases in the network, the viscosity of the network increases. As an important validation for the relationship between the energy landscape of a crosslinker chemistry and the resulting dynamic mechanical properties of a crosslinked ideal network hydrogel, this work enhances our understanding of deformation mechanisms in polymer networks that cannot easily be revealed by experiment and reveals design ideas that can lead to better performance of the polymer network at the macroscale.