Nanoscale Diffusion of Polymer-Grafted Nanoparticles in Entangled Polymer Melts

Abstract

We conducted a dissipative particle dynamics simulation on the motion of polymer-grafted nanoparticles in entangled polymer melts. Three regimes for the mean square displacement of the nanoparticles were discovered at different time scales. The nanoparticles undergo Brownian diffusion at short and long time scales and exhibit subdiffusive behavior at intermediate time scales. The short-time diffusion can be approximated as the motion of bare nanoparticles, while the long-time diffusion is associated with the entire polymer-grafted nanoparticle. The long-time Brownian diffusion was found to be non-Gaussian, which originates from the hopping diffusion of polymer-grafted nanoparticles in entangled polymer melts. The results nicely support the experimental findings and provide a comprehensive insight into the anomalous dynamics of polymer-grafted nanoparticles in polymer melts.

Highly Stretchable, Soft, Low-Hysteresis, and Self-Healable Ionic Conductive Elastomers Enabled by Long, Functional Cross-Linkers

“…The mobility of polymer chains was quantified by the time dependence of their mean square displacement (MSD) (see “S2.3 Mean Square Displacement” in the Supporting Information), as presented in Figure d. It can be seen that the MSD behaviors vary from the short-time linear stage to the sublinear stage and to the long-time linear stage . The MSD curves in the short time almost overlap, indicating the independence of short-time diffusion on the length L of cross-linkers (identical to the results in Figure a–3c).…”

Self-assembly of sequence-regulated amphiphilic copolymers with alternating rod and coil pendants

“…The DPD, introduced by Hoogerbrugge and Koelman and improved by Espanol and Warren, is a coarse-grained mesoscopic simulation approach. [38][39][40] The details of the DPD method can be found in Section S1 of the ESI. † In the DPD model, each bead represents a cluster of atoms or molecules.…”

Crosslinking Modulated Hierarchical Self-Assembly of Rod–Coil Diblock Copolymer Patchy Nanoparticles

“…We conducted dissipative particle dynamics (DPD) simulations on the hierarchical assembly of patchy nanoparticles. The DPD is a coarse-grained mesoscopic simulation approach for complex fluids. − The details of the DPD method can be found in Section 1 of the Supporting Information. The patchy nanoparticles are created by the self-assembly of rod–coil diblock copolymers and the crosslinking of coil blocks.…”