Scaling Perspective on Dynamics of Nanoparticles in Polymers: Length- and Time-Scale Dependent Nanoparticle-Polymer Coupling

Themotion of nanoparticles in a polymer matrix is dictatedbythe intricate coupling of the nanoparticles and surrounding polymers.Various length- and time-scale dependent features of nanoparticle-polymercoupling in a polymer matrix have been delineated in the past decadeby combining scaling theory and molecular simulations. Representativescenarios of nanoparticle dynamics in polymers, which embody the rolesof polymer matrix topology, the polymers grafted to nanoparticle surface,the anisotropic shape of nanoparticles, and an external driving force,are reviewed. The systems examined demonstrate both the richness ofthe physics in the nanoparticle-polymer coupling and the capabilityof the scaling-level description in providing unique insights intothe size- and time-dependence of nanoparticle mobility. Followinga review of recent work, more scenarios of nanoparticles in polymermatrices, which reflect new pieces of physics in the nanoparticle-polymercoupling, are discussed. Together with the advances in the chemicalsynthesis of nanoparticles and polymers as well as in the techniquesof tracking nanoparticle motion and measuring nanoparticle diffusivity,the microscopic picture of nanoparticle-polymer coupling revealedtheoretically and computationally is anticipated to aid in the manipulationof nanoparticles in complex polymeric environments and thus benefitmany technological applications.