Dynamics of entangled polymers subjected to reptation and drift

Abstract

In this work we formulate a model to study the dynamical response of entangled polymers subjected to a constant drift. The drift may originate from an internal activity that acts along the primitive path of the tube. Here, we expand our previous work (A. R. Tejedor and J. Ramirez, Macromolecules, 2019, 52, 8788–8792) and solve analytically the most significant observables of the theory, providing explicit results to observables not considered previously, such as the tangent–tangent correlation function and the dynamic structure factor. These analytical results are compared and verified by means of Brownian dynamics simulations of the tube model. Interestingly, while the mean squared displacement of the chain segments is always subdiffusive, the center of mass shows a superdiffusive regime when the magnitude of the drift is significant. We provide scaling arguments to explain this phenomenon. We also consider the effect of contour-length fluctuations and describe two different approaches to introduce a drift using active particles.