Abstract
The sliding dynamics along two asymmetric/symmetric axial chains of ring chains linked by a linear chainis investigated using molecular dynamics (MD) simulations. A novel sub-diffusion behavior is observed for ring chains sliding along eithera fixed rod-like chain or fluctuating axial chain on asymmetric/symmetric axial chainsat the intermediate time range due to their strongly interplay between two ring chains. However, two ring chains slide in the normal diffusion at along time range because their sliding dynamics can be regarded as an overall motion of two ring chains. For ring chains sliding on two symmetric/asymmetricaxial chains, the diffusion coefficient D of ring chains relies on the bending energy of axial chains (Kb) as well as the distance of two axial chains (d). There exists a maximum diffusion coefficient Dmax at d = d* in which ring chains slide at the fastest velocity due to the maximum conformational entropy for the linking chain between two ring chainsat d = d*. Ring chain slide on fixed rod-like axial chainsfaster in the symmetric axial chain case than that in the asymmetric axial chain case. However, ring chains slide on fluctuatingaxial chainsslower in the symmetric axial chain case than that in the asymmetric axial chain case. This investigation can provide insights into the effects of the linked chain conformation on the sliding dynamics of ring chains in a slide-ring gel.
Highlights
Rotaxanes, firstly reported by Harrison et al [1], are a class of mechanically interlocked molecules (MIMs) that are composed of ring chains and axial polymer chains bound together in a threaded structure.These moleculeshave attracted much attention for the potential advantages of the dynamic nature of the mechanical bond as a consequence of the low energy barrier for the rotation of the ring chains, or the sliding of the ring chains along the axial polymer chain [2]
The sliding dynamics of ring chains along rod-like and fluctuating axial chains on the asymmetric/symmetric chains in a simple slide-ring gelis studied by usingthe molecular dynamics (MD) simulation method
When ring chains slide along two symmetric axial chains, the diffusion coefficient D of the ring chain relies on the bending energy of axial chains (Kb) and the distance d of two axial chains
Summary
Firstly reported by Harrison et al [1], are a class of mechanically interlocked molecules (MIMs) that are composed of ring chains and axial polymer chains bound together in a threaded structure.These moleculeshave attracted much attention for the potential advantages of the dynamic nature of the mechanical bond as a consequence of the low energy barrier for the rotation of the ring chains, or the sliding of the ring chains along the axial polymer chain [2] Owing to their fascinating sliding dynamics, rotaxanes can be applied to molecular machines. We performed further investigations to study the sliding dynamics of ring chains on a knotted polymer chain in rotaxane and found that the sliding behavior of the ring chain exhibits a sub-diffusion at the intermediate time range resulting from the intra-strand interaction between the ring chain and the knotted axial chain in the knot crossing region [18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
