基于详细分子动力学模拟的环形聚合物在附近交叉区域的构象和粘度标度律

Scaling Laws for the Conformation and Viscosity of Ring Polymers in the Crossover Region around from Detailed Molecular Dynamics Simulations.

作者信息

Tsalikis Dimitrios G, Alatas Panagiotis V, Peristeras Loukas D, Mavrantzas Vlasis G

机构信息

Department of Chemical Engineering, University of Patras and FORTH/ICE-HT, Patras, GR 26504, Greece.

Molecular Thermodynamics and Modeling of Material Laboratory, Institute of Nanoscience and Nanotechnology, National Center of Scientific Research "Demokritos", GR-15310 Aghia Paraskevi, Greece.

出版信息

ACS Macro Lett. 2018 Aug 21;7(8):916-920. doi: 10.1021/acsmacrolett.8b00437. Epub 2018 Jul 13.

DOI:10.1021/acsmacrolett.8b00437

PMID:35650965

Abstract

We present results from detailed, atomistic molecular dynamics (MD) simulations of pure, strictly monodisperse linear and ring poly(ethylene oxide) (PEO) melts under equilibrium and nonequilibrium (shear flow) conditions. The systems examined span the regime of molecular weights () from sub-Rouse ( < ) to reptation ( ∼ 10 ), where denotes the characteristic entanglement molecular weight of linear PEO. For both PEO architectures (ring and linear), the predicted chain center-of-mass self-diffusion coefficients as a function of PEO are in remarkable agreement with experimental data. From the flow simulations under shear, we have extracted and analyzed the zero-shear viscosity of ring and linear PEO melts as a function of .

摘要

我们展示了在平衡和非平衡（剪切流）条件下，对纯的、严格单分散的线性和环状聚环氧乙烷（PEO）熔体进行详细的原子分子动力学（MD）模拟的结果。所研究的体系涵盖了分子量（）从低于Rouse链段（<）到缠结链段（~10）的范围，其中表示线性PEO的特征缠结分子量。对于两种PEO结构（环状和线性），预测的链质心自扩散系数作为PEO的函数，与实验数据显著吻合。从剪切流模拟中，我们提取并分析了环状和线性PEO熔体的零剪切粘度作为的函数。