Moghimi Esmaeel, Chubak Iurii, Ntetsikas Konstantinos, Polymeropoulos Georgios, Wang Xin, Carillo Consiglia, Statt Antonia, Cipelletti Luca, Mortensen Kell, Hadjichristidis Nikos, Panagiotopoulos Athanassios Z, Likos Christos N, Vlassopoulos Dimitris
Institute of Electronic Structure and Laser, FORTH, Heraklion 71110, Crete, Greece.
Department of Materials Science and Technology, University of Crete, Heraklion 71003, Crete, Greece.
Macromolecules. 2024 Jan 30;57(3):926-939. doi: 10.1021/acs.macromol.3c02088. eCollection 2024 Feb 13.
The design of functional polymeric materials with tunable response requires a synergetic use of macromolecular architecture and interactions. Here, we combine experiments with computer simulations to demonstrate how physical properties of gels can be tailored at the molecular level, using star block copolymers with alternating block sequences as a paradigm. Telechelic star polymers containing attractive outer blocks self-assemble into soft patchy nanoparticles, whereas their mirror-image inverted architecture with inner attractive blocks yields micelles. In concentrated solutions, bridged and interpenetrated hexagonally packed nanocylinders are formed, respectively, with distinct structural and rheological properties. The phase diagrams exhibit a peculiar re-entrance where the hexagonal phase melts upon both heating and cooling because of solvent-block and block-block interactions. The bridged nanostructure is characterized by similar deformability, extended structural coherence, enhanced elasticity, and yield stress compared to micelles or typical colloidal gels, which make them promising and versatile materials for diverse applications.
设计具有可调响应的功能性高分子材料需要协同利用高分子结构和相互作用。在此,我们将实验与计算机模拟相结合,以展示如何使用具有交替嵌段序列的星形嵌段共聚物作为范例,在分子水平上定制凝胶的物理性质。含有有吸引力的外部嵌段的遥爪星形聚合物自组装成软质斑点状纳米颗粒,而其具有内部有吸引力嵌段的镜像倒置结构则产生胶束。在浓溶液中,分别形成了具有独特结构和流变性质的桥接和互穿的六方堆积纳米圆柱体。相图呈现出一种特殊的再进入现象,由于溶剂嵌段和嵌段-嵌段相互作用,六方相在加热和冷却时都会熔化。与胶束或典型的胶体凝胶相比,桥接纳米结构具有相似的可变形性、扩展的结构连贯性、增强的弹性和屈服应力,这使其成为用于各种应用的有前途且通用的材料。