Srivastava Samanvaya, Agarwal Praveen, Mangal Rahul, Koch Donald L, Narayanan Suresh, Archer Lynden A
School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, United States.
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States.
ACS Macro Lett. 2015 Oct 20;4(10):1149-1153. doi: 10.1021/acsmacrolett.5b00319. Epub 2015 Sep 24.
Hyperdiffusive relaxations in soft glassy materials are typically associated with out-of-equilibrium states, and nonequilibrium physics and aging are often invoked in explaining their origins. Here, we report on hyperdiffusive motion in model soft materials comprised of single-component polymer-tethered nanoparticles, which exhibit a readily accessible Newtonian flow regime. In these materials, polymer-mediated interactions lead to strong nanoparticle correlations, hyperdiffusive relaxations, and unusual variations of properties with temperature. We propose that hyperdiffusive relaxations in such materials can arise naturally from nonequilibrium or non-Brownian volume fluctuations forced by equilibrium thermal rearrangements of the particle pair orientations corresponding to equilibrated shear modes.
软玻璃态材料中的超扩散弛豫通常与非平衡态相关，在解释其起源时常常会涉及非平衡物理和老化现象。在此，我们报告了由单组分聚合物连接的纳米颗粒构成的模型软材料中的超扩散运动，这些材料呈现出易于实现的牛顿流体流动状态。在这些材料中，聚合物介导的相互作用导致了强烈的纳米颗粒相关性、超扩散弛豫以及性质随温度的异常变化。我们提出，此类材料中的超扩散弛豫可能自然地源于与平衡剪切模式相对应的粒子对取向的平衡热重排所强制产生的非平衡或非布朗体积涨落。
