ETH Zürich, Department of Health Science and Technology, 8092 Zürich, Switzerland.
Nanoscale. 2013 Jun 21;5(12):5539-48. doi: 10.1039/c3nr01016c.
We combine tensile strength analysis and X-ray scattering experiments to establish a detailed understanding of the microstructural coupling between liquid-crystalline elastomer (LCE) networks and embedded magnetic core-shell ellipsoidal nanoparticles (NPs). We study the structural and magnetic re-organization at different deformations and NP loadings, and the associated shape and magnetic memory features. In the quantitative analysis of a stretching process, the effect of the incorporated NPs on the smectic LCE is found to be prominent during the reorientation of the smectic domains and the softening of the nanocomposite. Under deformation, the soft response of the nanocomposite material allows the organization of the nanoparticles to yield a permanent macroscopically anisotropic magnetic material. Independent of the particle loading, the shape-memory properties and the smectic phase of the LCEs are preserved. Detailed studies on the magnetic properties demonstrate that the collective ensemble of individual particles is responsible for the macroscopic magnetic features of the nanocomposite.
我们结合拉伸强度分析和 X 射线散射实验，深入了解了液晶弹性体 (LCE) 网络和嵌入的磁性核壳状椭圆形纳米粒子 (NPs) 之间的微观结构耦合。我们研究了不同变形和 NP 负载下的结构和磁重组，以及相关的形状和磁记忆特征。在拉伸过程的定量分析中，发现掺入的 NPs 在向列相 LCE 的重取向和纳米复合材料的软化过程中对向列相 LCE 的影响显著。在变形过程中，纳米复合材料的软响应使得纳米粒子的组织能够产生宏观各向异性的永久磁性材料。与粒子负载无关，LCE 的形状记忆特性和向列相得以保留。对磁性特性的详细研究表明，单个粒子的集体集合是纳米复合材料宏观磁性特征的原因。
