Theoretical reconstruction of realistic dynamics of highly coarse-grained cis-1,4-polybutadiene melts.
Theoretical reconstruction of realistic dynamics of highly coarse-grained cis-1,4-polybutadiene melts.
复制标题
高粗粒顺式 1,4-聚丁二烯熔体现实动力学的理论重建。
DOI：
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发表时间：
2013
影响因子：
4.4
通讯作者：
M. Guenza
中科院分区：
文献类型：
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作者：
I. Lyubimov;M. Guenza
重建的理论，从加速动力学的粗粒度系统的中尺度模拟测量的原子级链扩散，在这里应用到顺式-1，4-聚丁二烯熔体的动力学，其中每个链被描述为一个软相互作用的胶体颗粒。重新标度形式主义解释了由于粗粒化过程导致的熵变化和摩擦变化而对动力学的修正。通过包括这两个校正的动力学被重新缩放，以再现在原子水平上描述的系统的现实动力学。从粗粒顺式-1，4-聚丁二烯熔体的介观模拟中获得的重新缩放的扩散系数显示出与Tsolou等人[Macromolecules 38，1478（2005）]进行的联合原子模拟的数据良好的一致性。导出的单体摩擦系数被用作输入到合作动力学理论，该理论描述了在高分子液体中缓慢合作运动的瞬态区域中移动的聚合物的内部动力学。理论预测的时间相关函数显示出良好的协议与模拟在整个范围内的长度和时间尺度的数据。
The theory to reconstruct the atomistic-level chain diffusion from the accelerated dynamics that is measured in mesoscale simulations of the coarse-grained system, is applied here to the dynamics of cis-1,4-polybutadiene melts where each chain is described as a soft interacting colloidal particle. The rescaling formalism accounts for the corrections in the dynamics due to the change in entropy and the change in friction that are a consequence of the coarse-graining procedure. By including these two corrections the dynamics is rescaled to reproduce the realistic dynamics of the system described at the atomistic level. The rescaled diffusion coefficient obtained from mesoscale simulations of coarse-grained cis-1,4-polybutadiene melts shows good agreement with data from united atom simulations performed by Tsolou et al. [Macromolecules 38, 1478 (2005)]. The derived monomer friction coefficient is used as an input to the theory for cooperative dynamics that describes the internal dynamics of a polymer moving in a transient regions of slow cooperative motion in a liquid of macromolecules. Theoretically predicted time correlation functions show good agreement with simulations in the whole range of length and time scales in which data are available.