Real-Space Analysis of Branch Point Motion in Architecturally Complex Polymers
Real-Space Analysis of Branch Point Motion in Architecturally Complex Polymers
复制标题
结构复杂聚合物中分支点运动的实空间分析
DOI：
10.1021/ma501405n
复制
发表时间：
2014
期刊：
影响因子：
5.5
通讯作者：
A. Moreno
中科院分区：
文献类型：
--
作者：
P. Bačová;A. Moreno
通过大规模分子动力学模拟，我们研究了纯支化聚合物和星形链与线性链混合物中的分支点运动。我们对分支点轨迹进行纯粹基于几何密度的聚类分析，并识别强定位区域（陷阱）。我们的结果表明，分支点的运动可以被描述为运动的网络的陷阱在时间尺度对应的爬行制度。陷阱内的停留时间分布广泛，甚至延长到比侧臂弛豫时间长得多的时间。连续访问的陷阱之间的距离的分布是非常相似的所有调查的支化聚合物，即使管膨胀是强得多的星星/线性混合物比在纯支化系统。我们的分析表明，由分层模型引入的分支点的扩散率必须被理解为一个参数，以解释与水相关联的有效摩擦。
By means of large-scale molecular dynamics simulations, we investigate branch point motion in pure branched polymers and in mixtures of stars and linear chains. We perform a purely geometrical density-based cluster analysis of the branch point trajectories and identify regions of strong localization (traps). Our results demonstrate that the branch point motion can be described as the motion over a network of traps at the time scales corresponding to the reptation regime. Residence times within the traps are broadly distributed, even extending to times much longer than the side-arm relaxation time. The distributions of distances between consecutively visited traps are very similar for all the investigated branched polymers, even though tube dilation is much stronger in the star/linear mixtures than in the pure branched systems. Our analysis suggests that the diffusivity of the branch point introduced by hierarchical models must be understood as a parameter to account for the effective friction associated w...
影响因子：
5.5
作者：
Wang, Zuowei;Likhtman, Alexei E.;Larson, Ronald G.
通讯作者：
Larson, Ronald G.