# Single-Chain Nanoparticles under Homogeneous Shear Flow

## TL;DR

This study uses multi-scale hydrodynamics simulations to explore how single-chain nanoparticles behave under shear flow, revealing unique responses influenced by their network-like structure and topology.

## Contribution

First simulation study of SCNPs under shear flow, highlighting their distinct rheological behavior and the influence of topology on their dynamics.

## Key findings

- SCNPs exhibit shear response distinct from other macromolecules.
- Scaling exponents for shear dependence are largely topology-independent.
- High Weissenberg number dynamics show tumbling or tank-treading depending on topology.

## Abstract

Single-chain nanoparticles (SCNPs) are a new class of macromolecular objects, synthesized through purely intramolecular cross-linking of single polymer chains. We use a multi-scale hydrodynamics simulation approach to study, for the first time, SCNPs under shear flow. We investigate the case of irreversible SCNPs (permanent cross-links) in dilute solution. SCNPs emerge as a novel class of macromolecular objects with response to shear distinct from other systems such as linear chains, star polymers, rings or dendrimers. This is evidenced by the observed set of scaling exponents for the shear rate dependence of the SCNP static and dynamic properties. Surprisingly these exponents are, at most, marginally dependent on the specific topology of the SCNP (globular or sparse), suggesting that they are inherently related to the network-like character of the molecular architecture and not to its specific connectivity. At high Weissenberg numbers the dynamics of the sparse SCNPs is dominated by tumbling motion, whereas tank-treading predominates for the most globular SCNPs.