Transport of Star-Branched Polymers in Nanoscale Pipe Channels Simulated with Dissipative Particle Dynamics Simulation
Transport of Star-Branched Polymers in Nanoscale Pipe Channels Simulated with Dissipative Particle Dynamics Simulation
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DOI：
10.1021/ma100734r
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发表时间：
2010-06
期刊：
影响因子：
5.5
通讯作者：
Ziqi Li;Yajie Li;Yongmei Wang;Zhao‐Yan Sun;L. An
中科院分区：
文献类型：
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作者：
Ziqi Li;Yajie Li;Yongmei Wang;Zhao‐Yan Sun;L. An
用标准耗散粒子动力学(DPD)模拟方法研究了星形聚合物在管径至少为聚合物两倍的压力驱动下的输运过程。星形聚合物在本体溶液中的平衡动力学符合Zimm模型，说明DPD模拟正确地考虑了星形聚合物的流体动力相互作用。在压力驱动下，具有更多支臂的星形聚合物更多地向管道中心迁移，导致净速度更快，因此在管道中的停留时间更短。星形聚合物沿流动方向的拉伸行为与线性聚合物链相似，不同之处在于星形聚合物的Weissenberg数Wi应减去臂数f。重新调整Weissenberg数后，定义为链沿流动方向的半径旋转平方之比的拉伸比Sx与其在稀溶液中的相应值Rgx2之比，被发现与其在稀溶液中的相应值相比，具有更大的规律性。
Transport of star polymers under pressure-driven flow in a pipe with pipe radius being at least twice the size of polymers has been examined with standard dissipative particle dynamics (DPD) simulations. Equilibrium dynamics of star polymers in bulk solution were found to obey the Zimm model very well, indicating that DPD simulation correctly incorporates the hydrodynamic interaction in the stars. Under pressure-driven flow, star polymers with more arms were found to migrate toward the center of pipe more, leading to a net faster velocity and hence a shorter retention time in the pipe. The stretching of star polymers along the flow was found to follow similar scaling behavior as the linear polymer chains, except that the Weissenberg number Wi for the stars should be reduced by arm number f. After rescaling of the Weissenberg number, the stretch ratio Sx, defined as the ratio of square of radius gyration of the chains along the flow, Rgx2, over its corresponding value in dilute bulk solution, was found to ...