Magnetic liquid crystalline hybrid materials: Synthesis of anisotropic, magnetic hybrid materials by organised integration of nanoparticles in liquid crystalline matrices

通过在复杂的液晶基质中稳定磁性纳米颗粒，我们的目标是制备具有有趣的磁光特性的混合材料。纳米颗粒磁性粒子的整合导致粒子与液晶分子之间的复杂相互作用，并导致具有新颖结构和性质的各向异性软混合材料。在之前的资助期间，我们合成了各种球形和棒状铁氧体纳米颗粒。通过用多种（前）介晶配体官能化磁性纳米颗粒，磁性纳米颗粒的表面性质被特别工程化以产生稳定的液晶杂化物，例如在4-氰基-4 '-戊基联苯（5CB）中。为此，我们合成了潜水员（前）介晶配体，其中包含一个介晶单元（即氰基联苯，辛基联苯）和磁性纳米粒子的结合基团，两者都通过不同长度的烷基连接。该混合材料揭示了有趣的磁光特性。基于我们以前的结果，我们计划合成和使用树枝状，（前）介晶配体的稳定较大的和各向异性的磁性纳米粒子在液晶基质中，进一步提高磁光性能。特别是，我们希望利用形状各向异性磁性纳米粒子的潜力来控制中间相的序参数。在优先计划中，我们计划与其他小组合作，对磁光和流变特性进行基础研究。结果将作为进一步的理论研究的基础。

By stabilizing magnetic nanoparticles in complex, liquid crystalline matrices, we aim at the preparation of hybrid materials with interesting magneto-optical properties. The integration of nanoparticulate magnetic particles leads to complex interactions between the particles and the liquid crystal molecules and to anisotropic, soft hybrid materials with novel structures and properties. Within the previous funding periods, we synthesized a variety of spherical and rod-shape ferrite nanoparticles. Via the functionalization of the magnetic nanoparticles with divers (pro)mesogenic ligands, the surface properties of the magnetic nanoparticles were specifically engineered to yield stable, liquid crystalline hybrids, e.g. in 4-cyano-4‘-pentylbiphenyl (5CB). For this purpose, we synthesized divers (pro)mesogenic ligands, which contained a mesogenic unit (i.e. cyanobiphenyle, octylbiphenyle) and a binding group for the magnetic nanoparticles both linked by an alkyl group of varying length. The hybrid materials revealed interesting magneto-optical properties. Based on our previous results, we plan to synthesize and use dendritic, (pro)mesogenic ligands for the stabilization of larger and anisotropic magnetic nanoparticles in the liquid crystalline matrix, further improving the magneto-optical properties. In particular, we would like to exploit the potential of shape anisotropic magnetic nanoparticles to control the order parameters of the mesophase. In cooperation with other groups in the priority program we plan to do fundamental investigations on the magneto-optical and rheological properties. The results will serve as a basis for further theoretical investigations.