Shape-changing polymer micro-origami with fully reprogrammable spatio-temporal folding

形状变化材料在3D微电子、生物材料、机器人微系统和微流体系统、智能纺织品、光学等领域的设计中非常有前途，仅举几个最突出的例子。在这一领域，依赖于结构的聚合物折纸被证明是一种非常有前途的方法，这些结构可以在外部触发因素的作用下折叠。然而，到目前为止，它仍然受到几个基本限制：·不是经历一系列编程的折叠事件，通常结构只能在“全局折叠”和“全局展开”状态之间切换，以及·折叠或展开状态不能总是锁定在其折叠/展开配置中。该项目旨在克服这些限制，并引入完全灵活的折叠行为编程。利用含有光敏纳米颗粒的水凝胶/固体聚合物/水凝胶三层夹层实现自由程序折叠。纳米颗粒提供了通过照明局部驱动薄膜的可能性。两个对刺激响应的水凝胶层对薄膜在不同方向上的弯曲做出响应。低熔点的固体聚合物层位于水凝胶层之间，负责折叠的冻结和解冻。我们的方法将允许结合形状记忆聚合物的优点和水凝胶的优点，并消除它们的缺点。在这个项目中，我们将从根本上了解不同类型的形状变化材料之间的协同作用，以及它们与外部控制的纳米颗粒的相互作用。该项目结合了两个小组(Ionov和Fery)在形状改变材料和光学活性纳米颗粒以及聚合物/纳米颗粒杂化材料方面的免费专业知识。该项目将极大地推动变形材料领域的发展，使新技术得以开发。

Shape-changing materials are highly promising for design of 3D microelectronics, biomaterials, robotic microsystems and microfluidic systems, smart textiles, optics, to mention just the most prominent examples. Within this field, polymer origami, which relies on structures, which fold in response to external triggers, has turned out as a highly promising approach. However, so far, it still suffers from several fundamental restrictions: • rather than undergoing a programmed sequence of folding events, usually the structures can only switch between a “globally folded” and “globally unfolded” state and • folded or un-folded states cannot always be locked in their folded / unfolded configuration. This project aims to overcome these restrictions and introduce fully flexible programming of folding behavior. Freely programmed folding will be achieved using hydrogel/solid polymer/hydrogel trilayer sandwich, which contain photosensitive nanoparticles. The nanoparticles provide possibility to locally actuate the film by illumination. Two stimuli-responsible hydrogels layers are responsive for bending of the film in different direction. The solid polymer layer with low melting point, which is between hydrogel layers, is responsible for freezing and unfreezing of folding. Our approach will allow combining of advantages of shape-memory polymers with advantages of hydrogels and elimination of their disadvantages. In this project, we will fundamentally understand cooperative interactions of different kinds of shape-changing materials as well as their interaction with externally controlled nanoparticles. The project combines complimentary expertizes of two groups (Ionov and Fery) in shape-changing materials and optically active nanoparticles, as well as polymer/nanoparticle hybrid materials. The project will considerable advance field of shape-changing materials that will allow development of new technologies.