Influence of network topology on the swelling of polyelectrolyte nanogels

TL;DR

This study uses Monte Carlo simulations to explore how different network topologies influence the swelling behavior of polyelectrolyte nanogels, revealing that lower connectivity cross-links lead to higher swelling ratios and salt-induced de-swelling.

Contribution

It provides new insights into the effect of network topology on nanogel swelling, which was previously unclear, through systematic simulation analysis.

Findings

Lower connectivity cross-links increase swelling ratios.

Salt causes de-swelling of nanogels.

Network topology significantly affects nanogel response.

Abstract

It is well-known that the swelling behavior of ionic nanogels depends on their cross-link density, however it is unclear how different topologies should affect the response of the polyelectrolyte network. Here we perform Monte Carlo simulations to obtain the equilibrium properties of ionic nanogels as a function of salt concentration $C_s$ and the fraction $f$ of ionizable groups in a polyelectrolyte network formed by cross-links of functionality $z$. Our results indicate that the network with cross-links of low connectivity result in nanogel particles with higher swelling ratios. We also confirm a de-swelling effect of salt on nanogel particles.