Simulation of polymer chains in elongational flow. Kinetics of chain fracture and fragment distribution
Simulation of polymer chains in elongational flow. Kinetics of chain fracture and fragment distribution
复制标题
聚合物链拉伸流动的模拟。
DOI：
10.1063/1.463899
复制
发表时间：
1992
影响因子：
4.4
通讯作者：
J. Torre
中科院分区：
文献类型：
--
作者：
J. Cascales;J. Torre
本文使用布朗动力学技术对稀溶液中拉伸流动下聚合物链的断裂进行计算机模拟。将各个随机盘绕的链放置在稳定单轴流的驻点处，并监测它们随时间的演变以防止链断裂。这些链要么被建模为具有截止弹簧长度的劳斯链，要么被建模为服从莫尔斯势的弹簧链。动力学参数是一级动力学常数和半衰期。这些参数与伸长率和链长的依赖性以比例定律的形式表示，并对两个模型的结果进行了比较。还研究了由此产生的裂缝碎片的尺寸分布，发现它可能从尖锐的峰值到均匀的变化，具体取决于流动的强度。
In this paper the Brownian dynamics technique for computer simulation of the fracture of polymer chains in a dilute solution subjected to elongational flow was used. Individual randomly coiled chains are placed at the stagnation point of a steady, uniaxial flow, and their evolution with time is monitored for chain fracture. The chains are modeled either as Rouse chains with a cutoff spring length, or as chains of springs obeying a Morse potential. Kinetic parameters are the first‐order kinetic constant and the half‐life time. The dependence of these parameters with elongational rate and chain length is expressed in the form of scaling laws, and the results are compared for the two models. Also studied was the size distribution of the resulting fracture fragments, finding that it may vary from sharply peaked to uniform, depending on the strength of the flow.