Liquid-crystalline (LC) bio-inspired materials based on colloidal nanoparticles with anisotropic morphologies such as sheets, plates, rods and fibers were used as functional materials. They show stimuli-responsive behaviour under mechanical force and in electric and magnetic fields. Understanding the effects of external stimuli on the structures of anisotropic colloidal particles is important for the development of highly ordered structures. Recently, we have developed stimuli-responsive hydroxyapatite (HAP)-based colloidal LC nanorods that are environmentally-friendly functional materials. In the present study, the ordering behaviour of HAP nanorod dispersions, which show LC states, has been examined using in situ small-angle neutron scattering and rheological measurements (Rheo–SANS) under shearing force. The structural analyses and dynamic viscosity observations provided detailed information about the effects of shear force on the structural changes of HAP nanorods in D₂O dispersion. The present Rheo–SANS measurements unraveled three kinds of main effects of the shear force: the enhancement of interactions between the HAP nanorods, the alignment of HAP nanorods to the shear flow direction, and the formation and disruption of HAP nanorod assemblies. Simultaneous analyses of dynamic viscosity and structural changes revealed that the HAP nanorod dispersions exhibited distinctive rheological properties accompanied by their ordered structural changes.

中文翻译：

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剪切诱导的羟基磷灰石纳米棒复合材料胶体溶液的液晶相变行为。

基于具有各向异性形态的胶体纳米颗粒的液晶（LC）生物启发材料被用作功能材料，例如片，板，棒和纤维。它们在机械力以及电场和磁场中显示出刺激响应行为。了解外部刺激对各向异性胶体颗粒结构的影响对于开发高度有序的结构非常重要。最近，我们已经开发了基于刺激的羟基磷灰石（HAP）基胶体LC纳米棒，是环保的功能材料。在本研究中，已经使用原位研究了显示出LC状态的HAP纳米棒分散体的有序行为。在剪切力作用下的小角中子散射和流变学测量（Rheo–SANS）。结构分析和动态粘度观察提供了有关剪切力对D ₂ O分散体中HAP纳米棒结构变化影响的详细信息。目前的Rheo-SANS测量揭示了剪切力的三种主要影响：HAP纳米棒之间相互作用的增强，HAP纳米棒与剪切流向的对齐以及HAP纳米棒组件的形成和破坏。动态粘度和结构变化的同时分析表明，HAP纳米棒分散体表现出独特的流变性质，伴随着有序的结构变化。