Radhakrishnan Rangarajan, Underhill Patrick T
Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom.
Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Str., Troy, New York 12180, USA.
J Chem Phys. 2015 Apr 14;142(14):144901. doi: 10.1063/1.4917483.
Polyelectrolytes, polymers in poor solvents, polymers mixed with particles, and other systems with attractions and repulsions show formation of globules/structures in equilibrium or in flow. To study the flow behavior of such systems, we developed a simple coarse-grained model with short ranged attractions and repulsions. Polymers are represented as charged bead-spring chains and they interact with oppositely charged colloids. Neglecting hydrodynamic interactions, we study the formation of compact polymer structures called globules. Under certain conditions, increase in shear rate decreases the mean first passage time to form a globule. At other conditions, shear flow causes the globules to breakup, similar to the globule-stretch transition of polymers in poor solvents.
聚电解质、处于不良溶剂中的聚合物、与颗粒混合的聚合物以及其他具有吸引和排斥作用的体系，在平衡态或流动状态下会形成球状体/结构。为了研究此类体系的流动行为，我们开发了一个具有短程吸引和排斥作用的简单粗粒化模型。聚合物被表示为带电的珠-弹簧链，它们与带相反电荷的胶体相互作用。忽略流体动力学相互作用，我们研究了称为球状体的致密聚合物结构的形成。在某些条件下，剪切速率的增加会降低形成球状体的平均首次通过时间。在其他条件下，剪切流会导致球状体破裂，类似于处于不良溶剂中的聚合物的球状体-拉伸转变。
