Abstract The hydrodynamic properties of uncharged polymers of acrylamide has been investigated in 1,4-dioxane (DO) + water mixed solvent media at 303 K, 313 K and 323 K temperatures as probed by viscometry to explore the dimension and conformation of individual polymer molecules. In this study three different average molar masses of PAM, e.g., 8.9 × 106 (designated as Type-A), 1.6 × 106 (designated as Type-B), and 2.3 × 105 (designated as Type-C) g·mol−1 were employed. The unperturbed dimensions () under non-theta condition of polymer molecules has been determined for various solvent compositions clearly indicates that though DO acts as poor solvent in our system but some compositions of solvent acts as a good solvent. The temperature coefficient of unperturbed dimension has been found negative for polyacrylamide in the mixed solvent systems indicating a weak helical nature. Rheological stress sweep measurements of Type-A PAM solutions at 298 K reveal marked increase in elasticity upon addition of DO in the mixed solvent compared to that in pure solvent. In the shear viscosity profile a significant increase in critical shear rate is observed with increase in temperature from 293 K to 298 K. The results are discussed in the light of microstructural arrangement of the PAM aggregates under different physiological conditions. Graphical Abstract

中文翻译：

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聚丙烯酰胺在 1,4-二恶烷 + 水混合溶剂介质中的溶液和流变性能

摘要 丙烯酰胺不带电荷聚合物在 1,4-二恶烷 (DO) + 水混合溶剂介质中的流体力学性质已在 303 K、313 K 和 323 K 温度下通过粘度测定法探测，以探索单个聚合物分子的尺寸和构象。 . 在本研究中，三种不同的 PAM 平均摩尔质量，例如 8.9 × 106（指定为 Type-A）、1.6 × 106（指定为 Type-B）和 2.3 × 105（指定为 Type-C）g·mol− 1人被聘用。对于各种溶剂组合物，聚合物分子在非θ条件下的未扰动尺寸 () 清楚地表明，尽管 DO 在我们的系统中充当不良溶剂，但某些溶剂组合物充当良溶剂。已发现混合溶剂系统中聚丙烯酰胺的未扰动尺寸温度系数为负值，表明其具有弱螺旋性质。A 型 PAM 溶液在 298 K 下的流变应力扫描测量表明，与纯溶剂相比，在混合溶剂中加入 DO 后弹性显着增加。在剪切粘度曲线中，随着温度从 293 K 增加到 298 K，观察到临界剪切速率显着增加。根据不同生理条件下 PAM 聚集体的微观结构排列讨论结果。图形概要 在剪切粘度曲线中，随着温度从 293 K 增加到 298 K，观察到临界剪切速率显着增加。根据不同生理条件下 PAM 聚集体的微观结构排列讨论结果。图形概要 在剪切粘度曲线中，随着温度从 293 K 增加到 298 K，观察到临界剪切速率显着增加。根据不同生理条件下 PAM 聚集体的微观结构排列讨论了结果。图形概要