Complex Interactions with the Surroundings Dictate a Tagged Chain's Dynamics in Unentangled Polymer Melts

摘要: For more than half a century the theoretical landscape for single chain dynamics dense polymeric solutions and melts below entanglement threshold has been dominated by Rouse model independent phantom chains, supported ideas of hydrodynamic screening. There exists, however, large body literature from experiments, Monte Carlo, molecular simulations on deviations behavior unentangled homopolymer melts, showcased mostly in subdiffusive center-of-mass tagged chains at intermediate times, with subdiffusion exponent reported range 0.75–0.85. The influence surrounding length Ns motion N is key test, which, through high-precision numerical simulation we show that fails. Our central results are times chain’s moves subdiffusively, ⟨Δr2cm⟩ ∝ tα α = 0.87 ± ...