nanoparticle motion in entangled melts of linear and nonconcatenated ring polymers

• DOI: 10.17615/g0wx-2f69
• Publication Date: 2017-02-13
• Authors: Grest, Gary S.; Rubinstein, Michael; Halverson, Jonath...; Kalathi, Jagannat...; Ge, Ting
• Keywords: 01 natural sciences; 0104 chemical sciences

The motion of nanoparticles (NPs) in entangled melts of linear polymers and nonconcatenated ring polymers are compared by large-scale molecular dynamics simulations. The comparison provides a paradigm for the effects of polymer architecture on the dynamical coupling between NPs and polymers in nanocomposites. Strongly suppressed motion of NPs with diameter d larger than the entanglement spacing a is observed in a melt of linear polymers before the onset of Fickian NP diffusion. This strong suppression of NP motion occurs progressively as d exceeds a and is related to the hopping diffusion of NPs in the entanglement network. In contrast to the NP motion in linear polymers, the motion of NPs with d > a in ring polymers is not as strongly suppressed prior to Fickian diffusion. The diffusion coefficient D decreases with increasing d much slower in entangled rings than in entangled linear chains. NP motion in entangled nonconcatenated ring polymers is understood through a scaling analysis of the coupling betwe...