Effects of Precursor Topology and Synthesis under Crowding Conditions on the Structure of Single-Chain Polymer Nanoparticles

TL;DR

This study uses molecular dynamics simulations to explore how precursor topology and crowding conditions influence the structure and formation kinetics of single-chain polymer nanoparticles, revealing topology-dependent effects on morphology and formation speed.

Contribution

It demonstrates that precursor topology significantly affects SCNP structure and formation rate under crowding conditions, providing new insights into polymer nanoparticle synthesis.

Findings

Ring precursors produce more compact, spherical SCNPs at higher concentrations.

Crowding accelerates SCNP formation for both linear and ring precursors.

Precursor topology influences the retained conformation in dilute solutions.

Abstract

By means of molecular dynamics simulations we investigate the formation of single-chain nanoparticles through intramolecular cross-linking of polymer chains, in the presence of their precursors acting as purely steric crowders in concentrated solution. In the case of the linear precursors, the structure of the resulting SCNPs is weakly affected by the density at which the synthesis is performed. Crowding has significant effects if ring precursors are used: higher concentrations lead to the formation of SCNPs with more compact and spherical morphologies. Such SCNPs retain in the swollen state (high dilution) the crumpled globular conformations adopted by the ring precursors in the crowded solutions. Increasing the concentration of both the linear and ring precursors up to $30 \%$ leads to faster formation of the respective SCNPs.