Artie McFerrin Department of Chemical Engineering , Texas A&M University , College Station , Texas 77843 , United States.
Samuel Ginn Department of Chemical Engineering , Auburn University , Auburn , Alabama 36849 , United States.
Langmuir. 2018 Nov 6;34(44):13274-13282. doi: 10.1021/acs.langmuir.8b02350. Epub 2018 Oct 23.
A Landau-de Gennes formulation was implemented in dynamic finite element simulations to compare with postshear relaxation experiments that were conducted on cholesteric cellulose nanocrystal (CNC) dispersions. Our study focused on the microstructural reassembly of CNCs in lyotropic dispersions as parameters such as chiral strength and gap confinement were varied. Our simulation results show that homeotropic and/or more complicated three-dimensional helical configurations are possible, depending on the choice of these parameters. We also observed how dynamic banding patterns develop into the hierarchical microstructures that are characterized by an equilibrium pitch length in both the experiments and simulations. This work has immediate relevance for cellulose nanocrystal dispersion processing and provides new insight into fluid phase ordering for tailorable optical properties.
采用朗道-德热内（Landau-de Gennes）模型在动态有限元模拟中进行了比较，与在胆甾相纤维素纳米晶体（CNC）分散体上进行的后剪切松弛实验进行了比较。我们的研究集中在离液相分散体中 CNC 的微观结构重组上，因为参数如手性强度和间隙限制等都发生了变化。我们的模拟结果表明，根据这些参数的选择，可能存在向列和/或更复杂的三维螺旋结构。我们还观察了动态带状图案如何发展成为具有平衡螺距长度的实验和模拟中所具有的分层微观结构。这项工作与纤维素纳米晶体分散体加工直接相关，并为可定制光学性能的流体相有序提供了新的见解。
