标题： 界面纠缠诱导的聚合物流体时变凝固 显示英文标题

标题： Interfacial Entanglement-Induced Time-Dependent Solidification of Polymeric Fluids

摘要： 聚合物在固体界面的结构随时间演变，但其流变性质的相应变化仍知之甚少。 在这里，我们使用自制的石英音叉原子力显微镜纳米流变仪，直接测量了界面流体的时间依赖性粘弹性。 最靠近基底的底层在10小时内发生固化，表现出存储模量大约五倍的增加和损耗模量大约两倍的增加。 这是由于界面缠绕引起的，这是由固壁吸引力相互作用驱动的聚合物与固体表面的强结合所致。 相反，在第二层和第三层中，存储模量随时间几乎保持不变，而损耗模量则显示出大约两倍的增加。 在这个区域，与强结合的第一层不同，熵斥力占主导地位，使材料表现出类似流体的行为，同时变得越来越粘稠。 值得注意的是，当第一层（发生界面缠绕的层）发生固化时，界面流体流动的流动边界向上移动，远离基底，导致负滑移长度。 这突显了纳米尺度界面结构和性质在控制宏观流动行为中的关键作用。 显示英文摘要

摘要： The structure of polymers at solid interfaces evolves over time, but the corresponding changes in their rheological properties remain poorly understood. Here, using a home-built quartz tuning fork atomic force microscope-based nano-rheometer, we directly measure the time-dependent viscoelasticity of the interfacial fluid. The bottommost layer, closest to the substrate, undergoes solidification over 10 hours, exhibiting an approximately five-fold increase in storage modulus and a two-fold increase in loss modulus. This arises from interfacial entanglement due to the strong binding of polymers to the solid surface driven by solid-wall attractive interactions. In contrast, within the second and third layers, the storage modulus remains nearly constant over time, while the loss modulus shows approximately two-fold increase. In this region, unlike the strongly bound first layer, entropic repulsion dominates, allowing the material to behave fluid-like while becoming increasingly viscous. Notably, as the first layer, where interfacial entanglement occurs, undergoes solidification, the flow boundary for interfacial fluid flow shifts upward away from the substrate, resulting in a negative slip length. This highlights the critical role of nanoscale interfacial structure and properties in governing macroscopic flow behavior.