The design and production of anisotropic composites and nanocomposites has become increasingly relevant in materials science and engineering because they provide an opportunity of enhancing and adapting the properties of a material for specialized applications. This article reviews the strategies that have been developed to achieve anisotropy based on the position and orientation of the dispersed phase in polymer composites including polymer nanocomposites. Flow and electric field-driven alignment methodologies are briefly described, which is followed by a focus on magnetically oriented composites. The use of magnetic fields for this purpose has been of particular interest in recent years due to its ease of use and the variety of materials on which this method can be applied. Strong magnetic fields are required to align diamagnetic fillers. However, the modification of particles with low magnetic susceptibilities with magnetic nanoparticles (i.e. iron oxide nanoparticles) has been proven to be a successful approach to broaden the capabilities of magnetic alignment in polymer composites. The development of filler manipulation techniques opens the possibility to mimic complex biological structures that promise to improve the mechanical properties of bioinspired composites and even achieve advanced functionalities in self-shaping materials for example.

各向异性复合材料和纳米复合材料的设计和生产在材料科学和工程中变得越来越重要，因为它们提供了增强和适应特殊应用材料性能的机会。本文回顾了基于包括聚合物纳米复合材料在内的聚合物复合材料中分散相的位置和取向而开发的实现各向异性的策略。简要介绍了流动和电场驱动的对准方法，然后重点介绍了磁性取向的复合材料。由于磁场的易用性和可应用该方法的材料的多样性，近年来为此目的而特别关注使用磁场。需要强磁场来对准抗磁性填料。然而，已经证明用磁性纳米颗粒（即氧化铁纳米颗粒）修饰具有低磁化率的颗粒是扩大聚合物复合材料中磁性排列能力的成功方法。填料处理技术的发展为模仿复杂的生物结构提供了可能性，这些结构有望改善生物启发性复合材料的机械性能，甚至在自成型材料中实现先进的功能。