School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Department of Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania 19104, USA.
J Chem Phys. 2014 Mar 28;140(12):124903. doi: 10.1063/1.4868986.
Incorporation of nanorods (NRs) into a polymer matrix can greatly enhance the material properties, but the aggregation of NRs prevents the full realization of their potential. Using coarse-grained molecular dynamics simulation with the dissipative particle dynamics thermostat, we have systematically examined how key material and processing parameters, such as aspect ratio, particle diameter, rigidity and concentration of NR, polymer chain length, and shear rate can influence the placement and orientation of the self-aggregating NRs in a model polymer melt under shear. When compared with nanoparticles (NPs), the NRs tend to aggregate more severely even under strong shear flow. To improve the dispersion of NRs within the polymer matrix under a given flow condition, we incorporated additional NPs with selective interactions into polymer/NR composites, demonstrating that the current mesoscale simulation study offers insights on how to control the dispersion and orientation of NRs in polymer under shear flow.
将纳米棒（NRs）掺入聚合物基质中可以极大地增强材料性能，但 NRs 的聚集阻止了它们潜力的充分实现。我们使用耗散粒子动力学（DPD）热平衡的粗粒化分子动力学模拟，系统地研究了关键的材料和加工参数，如长径比、粒径、刚性和 NR 浓度、聚合物链长和剪切率，如何影响自组装 NRs在剪切下模型聚合物熔体中的位置和取向。与纳米颗粒（NPs）相比，即使在强剪切流下，NRs 也更容易发生严重聚集。为了在给定的流动条件下改善 NRs 在聚合物基质中的分散性，我们将具有选择性相互作用的额外 NPs 掺入聚合物/NR 复合材料中，表明当前的介观模拟研究提供了如何控制剪切流下聚合物中 NRs 的分散和取向的见解。
