利用Poiseuille方程确定聚乙烯醇在粘度计毛细管管壁上吸附层的厚度

Thickness of the Polyvinyl Alcohol Layers Adsorbed on the Wall of Viscometer Capillary Determined According to Poiseuille Equation

利用高分子溶液流过时间测量之前和之后纯溶剂流过时间的变化不仅再次证实了极低浓度区高分子溶液反常粘度行为的起源和校正方法,而且找到了定量研究粘度计毛细管管壁上高分子吸附层厚度的实验方法。研究结果表明,溶剂的性质对高分子吸附层厚度有着显著影响。

The flow time of polymer solution and solvent will be affected by the polymer layers adsorbed on the wall of viscometer capillary. As a result, the viscosity behavior of the polymer solution in extremely dilute concentrations is greatly changed with the flow time of the solvent by which the viscosity of the polymer solution is determined. Both the flow time of the solvent t0', obtained after the flow of polymer solution, and the flow time of the solvent t0, obtained before the flow of polymer solution were determined. By using t0' and t0 , the abnormal viscosity behavior of the polymer solution at extremely dilute concentrations was interpreted reasonably and the influence of the adsorbed polymer upon the viscosity of the polymer solution was deleted completely. It is peculiarly interesting is that the difference between t'0 and t0 can be used to determine the thickness of the polymer layers absorbed on the wall of viscometer capillary quantitatively. And noted that the thickness of the adsorbed polymer layers is greatly associated with the solvent by which the polymer molecules are dissolved. 