Sliding Dynamics of Slide-Ring Polymers Based on the Bead-Spring Model

Understanding the sliding dynamics is critical for developing rotaxane-based mechanically interlocked polymers.In this work,we studied the sliding behavior of a sliding ring and its influence on the dynamics of attached polymer chains based on the heterogeneous beadspring model.The sliding constraint was treated as direction-related confinement with the heterogeneous friction coefficient and constraint intensity.The relaxation spectrum,the diffusion dynamics,and the sliding dynamics under/after drag were studied for typical sliding chain topologies,namely,the sliding dangling chain,the constraint sliding chain,and the sliding strand.Compared with the non-sliding chains(such as the free chain,the dangling chain,and the network strand),the slide of one or two chain ends induces an additional slow process in the transition from the Rouse-type behavior to the long-time terminal behavior.The effect of the sliding-related process on the diffusion of specific chain segments relies on the chain topology.The slow sliding relaxation process is also observed in the sliding process during and after chain deformation,whose characteristic time is at least three times the terminal relaxation time of the free chain with the same length,and will increase with the friction coefficient(i.e.,the interaction)between the ring and the polymer axial.The results of this work will benefit the understanding of the sliding dynamics in experiments.