Elasticity of polymeric nanocolloidal particles

• DOI: 10.1038/srep15854
• Publication Date: 2015-11-02T10:35:42Z
• Authors: Jonas Riest; Labrini Athanasop...; Sergei A. Egorov; Christos N. Likos; Primož Ziherl
• Keywords: DYNAMICS; info:eu-repo/classification/ddc/000; 103015 Kondensierte Materie; Polymers; STAR POLYMERS; SURFACE-TENSION; CARBON NANOTUBES; 01 natural sciences; Article; 103023 Polymerphysik; 103015 Condensed matter; DEFORMATION; 0103 physical sciences; Statistical physics, thermodynamics and nonlinear dynamics; 103023 Polymer physics; 103029 Statistical physics; 103029 Statistische Physik; COLLOIDAL PARTICLES; QUASI-CRYSTALS; 103036 Theoretische Physik; CONFORMATION; 103036 Theoretical physics; GRAFTED NANOPARTICLES; MECHANICS

AbstractSoftness is an essential mechanical feature of macromolecular particles such as polymer-grafted nanocolloids, polyelectrolyte networks, cross-linked microgels as well as block copolymer and dendrimer micelles. Elasticity of individual particles directly controls their swelling, wetting and adsorption behaviour, their aggregation and self-assembly as well as structural and rheological properties of suspensions. Here we use numerical simulations and self-consistent field theory to study the deformation behaviour of a single spherical polymer brush upon diametral compression. We observe a universal response, which is rationalised using scaling arguments and interpreted in terms of two coarse-grained models. At small and intermediate compressions the deformation can be accurately reproduced by modelling the brush as a liquid drop, whereas at large compressions the brush behaves as a soft ball. Applicable far beyond the pairwise-additive small-strain regime, the models may be used to describe microelasticity of nanocolloids in severe confinement including dense disordered and crystalline phases.