Effect of topology and concentration on the scaling, structure and dynamics of single-chain nanoparticles.

Single-chain nanoparticles (SCNPs) are soft nano-objects that are synthesized through intramolecular cross-linking of single polymer chains (precursors) and have promising applications in nanomedicine, bioimaging, biosensing, catalysis or rheology among others. Because of the self-avoiding nature of the precursor conformations in the standard good solvent conditions of synthesis, cross-links involving long loops are rare and intramolecular compaction is not achieved. Instead, the resulting SCNPs are generally sparse multi-loop objects with scaling exponents about 0.5, similar to those found for intrinsically disordered proteins.

In this contribution we review theoretical and simulation work on the effect of SCNP topology in their scaling properties and the structure and dynamics of fluids, gels, melts and nanocomposites based on SCNPs with reversible or irreversible bonds. The discussion includes routes for synthesizing SCNPs with globular architectures, crowding effects on SCNP conformations, anomalous glassy physics, shear flow properties, topological interactions in nanocomposites and properties of SCNP-based vitrimer networks.