Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.
Department of Materials, ETH Zurich, Zurich, Switzerland.
Nat Commun. 2023 Feb 4;14(1):607. doi: 10.1038/s41467-023-36292-8.
In Nucleation and Growth, the process by which most heterogeneous systems form, thermodynamics sets the asymptotic boundaries toward which the system must evolve, while kinetics tries to cope with it by imposing the transport rates. In all heterogeneous colloidal systems observed in nature, composition, shape, structure and physical properties result from the trade-off between thermodynamics and kinetics. Here we show, by carefully selecting colloidal systems and controlling phase separation in microfluidic devices, that it becomes possible to disentangle kinetics effects from thermodynamics. Using amyloids and nanocellulose filamentous colloids, we demonstrate that decoupling kinetics from thermodynamics in the phase separation process unveils new physical phenomena, such as orders of magnitude shorter timescales, a wider phase diagram, and structures that are not observable via conventional liquid-liquid phase separation. Our approach enables on-demand fabrication of multicomponent heterogeneous liquid crystals, enhancing their potential, and introducing original fundamental and technological directions in multicomponent structured fluids.
在成核和生长过程中，大多数多相体系的形成过程，热力学设定了体系必须演化的渐近边界，而动力学则试图通过施加输运速率来应对。在自然界中观察到的所有多相胶体体系中，组成、形状、结构和物理性质都是热力学和动力学之间权衡的结果。在这里，我们通过仔细选择胶体体系并在微流控装置中控制相分离，证明了可以将动力学效应与热力学效应分离开来。我们使用淀粉样蛋白和纳米纤维素丝状胶体，证明了在相分离过程中，将动力学与热力学解耦揭示了新的物理现象，例如数量级更短的时间尺度、更宽的相图以及通过传统的液-液相分离无法观察到的结构。我们的方法能够按需制造多组分多相液晶，增强了它们的潜力，并在多组分结构流体中引入了新的基础和技术方向。
