Controlling the nanoparticle (NP) diffusion in polymers is a prerequisite to obtain polymer nanocomposites (PNCs) with desired dynamical and rheological properties and to achieve targeted delivery of nanomedicine in biological systems. Here we determine the suppression mechanism of direct NP–polymer attraction to hamper the NP mobility in adsorbing polymers and then quantify the dependence of the effective viscosity η_eff felt by the NP on the adsorption duration τ_ads of polymers on the NP using scaling theory analysis and molecular dynamics simulations. We propose and confirm that participation of adsorbed chains in the NP motion break up at time intervals beyond τ_ads due to the rearrangement of polymer segments at the NP surface, which accounts for the onset of Fickian NP diffusion on a time scale of t ≈ τ_ads. We develop a power law, η_eff ∼ (τ_ads)^ν, where ν is the scaling exponent of the dependence of polymer coil size on the chain length, which leads to a theoretical basis for the design of PNCs and nanomedicine with desired applications through tuning the polymer adsorption duration.

中文翻译：

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调节吸附持续时间以控制纳米颗粒在吸附聚合物中的扩散

控制聚合物中的纳米颗粒（NP）扩散是获得具有所需动力学和流变特性的聚合物纳米复合材料（PNC），并在生物系统中实现纳米药物靶向递送的先决条件。在这里，我们确定直接NP-聚合物吸引力的抑制机制，以阻碍在吸附聚合物的NP迁移率，然后量化有效粘度的依赖性η _EFF由NP的吸附持续时间τ毡_广告上的NP的聚合物的使用标度理论分析和分子动力学模拟。我们建议，并确认在NP运动吸附链的参与，在τ以外的时间间隔分手_广告由于聚合物链段的在NP表面的重排，其占菲克扩散NP的发作上的时间刻度吨≈τ_广告。我们开发幂定律，η _EFF〜（τ_广告）^ν，其中ν是聚合物线圈尺寸对链长度的依赖性，所述标度指数，这导致对于PNCS的设计和纳米带通过期望的应用的理论基础调整聚合物的吸附时间。