发表机构
Department of Chemical Science and Engineering, Kyoto University; Advanced Manufacturing Technology Institute, Kanazawa University（京都大学化学工程系; 金泽大学先进制造技术研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文通过拉伸-取向分解构建本构模型，揭示未缠结聚合物熔体非线性剪切流变的取向起源，模型再现稳态剪切标度并预测有限第二法向应力系数。
AI 中文摘要
通过聚合物动力学的拉伸-取向分解，研究了未缠结聚合物熔体的普适流变性质。通过将拉伸从每个Rouse模式的显式状态中外部化，我们构建了一个具有取向动力学的本构模型，该模型保留了Rouse松弛谱。所得模型再现了所观察到的稳态剪切粘度和第一法向应力系数的标度关系，预测了有限的第二法向应力系数，并近似复现了Cox-Merz和Gleissle-Osaki规则。推导出的稳态-振荡剪切对应关系进一步识别出一个与第一法向应力差相关的弹性贡献，该贡献在传统的Cox-Merz规则中缺失。
英文摘要
Universal rheological properties of unentangled polymer melts are investigated through the stretch-orientation decomposition of polymer dynamics. By externalizing stretch from the explicit state of each Rouse mode, we construct a constitutive model with orientational kinetics that preserves the Rouse relaxation spectrum. The resulting model yields the observed steady-shear scalings of the shear viscosity and first normal-stress coefficient, predicts a finite second normal-stress coefficient, and approximately reproduces the Cox-Merz and Gleissle-Osaki rules. The derived steady-oscillatory shear correspondence further identifies an elastic contribution, associated with the first normal stress difference, that is absent from the conventional Cox-Merz rule.
Comments5 pages, 4 figures. Companion paper: arXiv:2610.00892
