Elongational viscosity data of well-characterized solutions of 3–50% weight fraction of monodisperse polystyrene PS-820k (molar mass of 820,000 g/mol) dissolved in oligomeric styrene OS8.8 (molar mass of 8800 g/mol) as reported by André et al. (Macromolecules 54:2797–2810, 2021) are analyzed by the Extended Interchain Pressure (EIP) model including the effects of finite chain extensibility. Excellent agreement between experimental data and model predictions is obtained, based exclusively on the linear-viscoelastic characterization of the polymer solutions. The data were obtained by a filament stretching rheometer, and at high strain rates and lower polymer concentrations, the stretched filaments fail by rupture before reaching the steady-state elongational viscosity. Filament rupture is predicted by a criterion for brittle fracture of entangled polymer liquids, which assumes that fracture is caused by scission of primary C-C bonds of polymer chains when the strain energy reaches the bond-dissociation energy of the covalent bond (Wagner et al., J. Rheology 65:311–324, 2021).

André 报告的 3–50% 重量分数的单分散聚苯乙烯 PS-820k（摩尔质量为 820,000 g/mol）溶解在低聚苯乙烯 OS8.8（摩尔质量为 8800 g/mol）中的良好表征溶液的伸长粘度数据等。(Macromolecules 54:2797–2810, 2021) 通过扩展链间压力 (EIP) 模型进行分析，包括有限链可扩展性的影响。完全基于聚合物溶液的线性粘弹性表征，获得了实验数据和模型预测之间的极好一致性。数据是通过长丝拉伸流变仪获得的，在高应变率和较低的聚合物浓度下，拉伸的长丝在达到稳态拉伸粘度之前因破裂而失效。