Dynamically Heterogeneous Relaxation of Entangled Polymer Chains
Dynamically Heterogeneous Relaxation of Entangled Polymer Chains
复制标题
缠结聚合物链的动态非均相松弛
DOI：
10.1103/physrevlett.120.267801
复制
发表时间：
2018
影响因子：
8.6
通讯作者：
Schroeder, Charles M.
中科院分区：
文献类型：
--
作者：
Zhou, Yuecheng;Schroeder, Charles M.
缠结的聚合物液体的变形后的应力松弛被认为是受到链缠结的瞬时重整。在这项工作中，我们使用单分子技术来研究单个聚合物在从非纠缠到纠缠溶液的过渡状态下的弛豫。我们的研究结果揭示了聚合物弛豫行为的动态异质性的出现，包括由单模和双模指数弛豫过程描述的不同分子亚群。较慢的双模时间尺度与特征蠕动时间一致，而单模时间尺度和快双模时间尺度归因于由于变形引起的瞬态解纠缠的局部区域。
Stress relaxation following deformation of an entangled polymeric liquid is thought to be affected by transient reforming of chain entanglements. In this work, we use single molecule techniques to study the relaxation of individual polymers in the transition regime from unentangled to entangled solutions. Our results reveal the emergence of dynamic heterogeneity underlying polymer relaxation behavior, including distinct molecular subpopulations described by a single-mode and a double-mode exponential relaxation process. The slower double-mode timescaleis consistent with a characteristic reptation time, whereas the single-mode timescaleand the fast double-mode timescaleare attributed to local regions of transient disentanglement due to deformation.