A thorough study is made of the dependences on salt concentration and polymer chain lengths of the low-frequency plateau of coacervates of poly (diallyl dimethyl ammonium chloride), PDADMAC, and poly (sodium 4-styrenesulfonate), PSS. The reliability and reproducibility of these measurements are carefully checked by determining the frequency-dependent stress limits of the rheometer through the use of reference fluids and by repeat experiments with coacervates. Long-time frequency sweeps show that coacervates with less salt are more repeatable than those with higher salt. A low-frequency plateau reliably appears only below a critical salt concentration, and the magnitude of the plateau depends strongly on salt concentration and chain lengths of both polycation and polyanion. It is only present for the molecular weight of the polycation, PDADMAC, higher than 100 kDa, but the magnitude of the plateau is more strongly influenced by the chain length of the polyanion, PSS. Possible causes of the low-frequency plateau are discussed.

中文翻译：

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聚电解质凝聚层线性粘弹性的低频弹性平台

对聚（二烯丙基二甲基氯化铵）、PDADMAC 和聚（4-苯乙烯磺酸钠）、PSS 的凝聚层低频平台对盐浓度和聚合物链长度的依赖性进行了深入研究。这些测量的可靠性和可重复性通过使用参考流体和通过凝聚层的重复实验确定流变仪的频率相关应力极限来仔细检查。长时间的频率扫描表明，含盐量少的凝聚层比含盐量高的凝聚层更具可重复性。低频平台只出现在临界盐浓度以下，平台的大小很大程度上取决于盐浓度和聚阳离子和聚阴离子的链长。它仅针对聚阳离子 PDADMAC 的分子量而存在，高于 100 kDa，但平台的大小受聚阴离子链长 PSS 的影响更大。讨论了低频平台的可能原因。