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A study of the thermodynamic and rheological properties of polymer and polyelectrolyte dilute solutions.

机译：聚合物和聚电解质稀溶液的热力学和流变性质的研究。

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摘要

An incompressible fluid flowing through a porous medium must undergo local velocity fluctuations as the local flow path cross-sectional area varies. If a small amount of a linear polymer is dissolved in the fluid, the fluid drag forces elongate the solvated polymer coils where the fluid is accelerating and compress the polymer coils where the fluid is decelerating. Polymer coil resistance to such deformations can result in a great increase in the fluid apparent viscosity as compared to the solvent apparent viscosity in absence of dissolved polymer.; An apparent correlation exists between dilute polymer solution flow resistance in porous media and the average size of a dissolved polymer coil. A measure of polymer coil size in solution is the solution zero-shear intrinsic viscosity. A model equation was developed from existing theory to describe polymer solution intrinsic viscosity as a function of polymer molecular weight and fluid temperature. The model was verified using intrinsic viscosity data collected experimentally and gathered from the scientific literature. A second model equation was derived from empirical results describing the solution intrinsic viscosity of a charged polymer as a function of solution ionic strength. The model relates three dimensionless groups of parameters that describe a polyelectrolyte in solution. An extensive assembly of experimental data and of data from the scientific literature was used to test the predictive capability of the model. A nearuniversal correlation was established between dimensionless quantities, but data for two polymer types deviated from the trend.; A custom extensional rheometer was used to test the correlation of solution extensional flow resistance with polymer hydrodynamic size. A packed bed of small mesh screens simulated fluid flow through a porous medium, thus creating an extensional fluid flow field. Dilute polymer solution resistances to flow through the packed bed were measured, and polymer coil extensional viscosities were derived from the experimental results. A critical fluid strain rate was identified beyond which polymer coils experience extensional strain and enhance the solution viscosity. Finally, polymer coil extensional viscosity was related to solution intrinsic viscosity, and the fluid yield flow rate for coil extension was related to the polymer coil hydrodynamic diameter. The model equations can, therefore, be used to predict dilute polymer solution flow resistance in porous media based on macromolecular chemical structure and solution conditions.
机译：当局部流动路径的横截面积变化时，流经多孔介质的不可压缩流体必须经历局部速度波动。如果少量的线性聚合物溶解在流体中，则流体的拖曳力会使流体在加速时的溶剂化聚合物线圈伸长，而在流体在减速时会压缩聚合物线圈。与不存在溶解的聚合物的情况下的溶剂表观粘度相比，聚合物线圈对这种变形的抵抗力可导致流体的表观粘度大大提高。多孔介质中稀聚合物溶液的流动阻力与溶解的聚合物线圈的平均尺寸之间存在明显的相关性。溶液中聚合物卷材尺寸的度量是溶液零剪切特性粘度。根据现有理论开发了一个模型方程，用于描述聚合物溶液的特性粘度随聚合物分子量和流体温度的变化。使用通过实验收集并从科学文献中收集的特性粘度数据验证了该模型。从描述带电聚合物的溶液特性粘度随溶液离子强度变化的经验结果中得出了第二个模型方程。该模型涉及描述溶液中的聚电解质的三组无量纲参数。实验数据和来自科学文献的数据的广泛组合用于测试模型的预测能力。在无因次数量之间建立了接近普遍的相关性，但是两种聚合物类型的数据却偏离了趋势。使用定制的拉伸流变仪来测试溶液拉伸流动阻力与聚合物流体力学尺寸的相关性。小筛网的填充床模拟了通过多孔介质的流体流动，因此产生了扩展的流体流场。测量了稀聚合物溶液流经填充床的阻力，并从实验结果中得出了聚合物卷材的拉伸粘度。确定了临界流体应变速率，超过该速率，聚合物卷材将经历拉伸应变并提高溶液粘度。最后，聚合物盘管的拉伸粘度与溶液的特性粘度有关，而用于盘管拉伸的流体屈服流速与聚合物盘管的流体动力学直径有关。因此，基于大分子化学结构和溶液条件，模型方程可用于预测多孔介质中稀聚合物溶液的流动阻力。

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  • 作者

    Rushing, Todd Stephen.;

  • 作者单位

    The University of Southern Mississippi.;

  • 授予单位 The University of Southern Mississippi.;
  • 学科 Chemistry Polymer.; Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2004
  • 页码 131 p.
  • 总页数 131
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 高分子化学（高聚物）;工程材料学;
  • 关键词

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