The
motion of nanoparticles in a polymer matrix is dictated
by
the intricate coupling of the nanoparticles and surrounding polymers.
Various length- and time-scale dependent features of nanoparticle–polymer
coupling in a polymer matrix have been delineated in the past decade
by combining scaling theory and molecular simulations. Representative
scenarios of nanoparticle dynamics in polymers, which embody the roles
of 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 of
the physics in the nanoparticle–polymer coupling and the capability
of the scaling-level description in providing unique insights into
the size- and time-dependence of nanoparticle mobility. Following
a review of recent work, more scenarios of nanoparticles in polymer
matrices, which reflect new pieces of physics in the nanoparticle–polymer
coupling, are discussed. Together with the advances in the chemical
synthesis of nanoparticles and polymers as well as in the techniques
of tracking nanoparticle motion and measuring nanoparticle diffusivity,
the microscopic picture of nanoparticle–polymer coupling revealed
theoretically and computationally is anticipated to aid in the manipulation
of nanoparticles in complex polymeric environments and thus benefit
many technological applications.