Osaka Municipal Technical Research Institute (OMTRI), Osaka 536-8553, Japan.
Soft Matter. 2017 May 31;13(21):3927-3935. doi: 10.1039/c7sm00284j.
The recent growing interest in the applications of gold nanowires (AuNWs) as flexible materials has raised the fundamental issue of how their mechanical properties are related to their morphology. In this work, to address this issue, the systematic synthesis of AuNWs, their structural analysis, and their rheological investigation were demonstrated. The structural analysis of AuNWs was performed based on TEM observations and light-scattering experiments. From these observations, it was found that the length of AuNWs varies from nanometer to micrometer depending on the reaction time while a constant width of 1.6 nm is maintained. On the basis of static light-scattering experiments and a wormlike chain model, the structural parameters of AuNWs during their growth were successfully obtained. When the contour length of AuNWs reached around 5 μm, the AuNW solution showed non-Newtonian behavior and appeared to behave as a gel. Dynamic viscoelasticity measurements indicated that such viscous behavior is responsible for entanglement between AuNWs. It is concluded that AuNWs are analogous with conventional polymers in terms of both their structure and their rheological behavior.
最近，人们对金纳米线（AuNWs）作为柔性材料的应用越来越感兴趣，这引发了一个基本问题，即它们的机械性能与其形态有何关系。在这项工作中，为了解决这个问题，我们系统地合成了 AuNWs，对其进行了结构分析，并对其流变性能进行了研究。AuNWs 的结构分析是基于 TEM 观察和光散射实验进行的。从这些观察结果中发现，AuNWs 的长度从纳米到微米不等，这取决于反应时间，而其宽度则保持在 1.6nm 不变。基于静态光散射实验和蠕虫链模型，成功获得了 AuNWs 在生长过程中的结构参数。当 AuNWs 的轮廓长度达到约 5μm 时，AuNW 溶液表现出非牛顿行为，表现为凝胶状。动态粘弹性测量表明，这种粘性行为是 AuNWs 之间缠结的原因。结论是，AuNWs 在结构和流变行为方面与传统聚合物类似。
