Laboratory of Experimental Methods in Transport Phenomena (LaMEFT) Mechanical Engineering Department, Technological Center, Federal University of Espírito Santo, 29075-910 Vitória, ES, Brazil.
Laboratory of Experimental Methods in Transport Phenomena (LaMEFT) Mechanical Engineering Department, Technological Center, Federal University of Espírito Santo, 29075-910 Vitória, ES, Brazil.
Int J Biol Macromol. 2019 Sep 15;137:1121-1129. doi: 10.1016/j.ijbiomac.2019.07.042. Epub 2019 Jul 9.
Drag reduction by the addition of polymer additives has been widely studied. However, there are only a few studies on binary polymer mixtures, here named blends. In this work, xanthan gum, polyacrylamide and poly(ethylene oxide) were associated with guar gum and drag reduction was used as a parameter to determine the synergistic interaction between polymers. The aim was to verify the relation of the synergy with the rigidity of the polymeric chains, the molecular weights and the magnitude of the molecular interactions between the studied polymers. To that end, several ratios of mixtures were tested at different Reynolds numbers in a rotational rheometer with double-gap concentric cylinders geometry. Finally, experiments were done to verify the behaviour of the blends over time at a fixed Reynolds number. From all these tests, it was documented that blends containing rigid chain polymers show positive synergism in the interaction in at least one of the ratios and that this interaction is more pronounced when the molecular weights are closer and intermolecular forces are stronger. It was also noted that, in general, blends are great substitutes for solutions containing only one type of polymer.
聚合物添加剂的减阻作用已得到广泛研究。然而，关于二元聚合物混合物（这里称为共混物）的研究却很少。在这项工作中，黄原胶、聚丙烯酰胺和聚氧化乙烯与瓜尔胶结合，并将减阻作用作为参数来确定聚合物之间的协同相互作用。目的是验证协同作用与聚合物链的刚性、分子量以及研究聚合物之间分子相互作用的大小之间的关系。为此，在具有双隙同心圆柱几何形状的旋转流变仪中，在不同的雷诺数下测试了几种混合物的比例。最后，在固定雷诺数下进行了实验以验证混合物随时间的行为。从所有这些测试中，可以证明至少在一个比例中，含有刚性链聚合物的共混物在相互作用中表现出正协同作用，并且当分子量更接近且分子间作用力更强时，这种相互作用更为明显。还注意到，一般来说，共混物是仅含有一种类型聚合物的溶液的很好替代品。
