Natali Laura, Caprini Lorenzo, Cecconi Fabio
Dipartimento di Fisica, Università"Sapienza", Piazzale A. Moro 5, I00185 Rome, Italy.
Soft Matter. 2020 Mar 11;16(10):2594-2604. doi: 10.1039/c9sm02258a.
We study the dynamics of a polymer, described as a variant of a Rouse chain, driven by an active terminal monomer (head). The local active force induces a transition from a globule-like to an elongated state, as revealed by the study of the end-to-end distance, the variance of which is analytically predicted under suitable approximations. The change in the relaxation times of the Rouse-modes produced by the local self-propulsion is consistent with the transition from globule to elongated conformations. Moreover, also the bond-bond spatial correlation for the chain head are affected by the self-propulsion and a gradient of over-stretched bonds along the chain is observed. We compare our numerical results both with the phenomenological stiff-polymer theory and several analytical predictions in the Rouse-chain approximation.
我们研究了一种聚合物的动力学，该聚合物被描述为受活性末端单体（头部）驱动的Rouse链变体。通过对端到端距离的研究发现，局部活性力会诱导聚合物从球状转变为伸长状态，在适当近似下，其方差可通过解析方法预测。局部自推进产生的Rouse模式弛豫时间的变化与从球状构象到伸长构象的转变一致。此外，链头的键-键空间相关性也受到自推进的影响，并且观察到沿着链存在过度拉伸键的梯度。我们将数值结果与唯象刚性聚合物理论以及Rouse链近似中的几个解析预测进行了比较。
