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首页> 外文期刊>Journal of Applied Polymer Science >Novel methods for the characterization of water-soluble polymers
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Novel methods for the characterization of water-soluble polymers

机译：表征水溶性聚合物的新方法

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The liquid chromatography of four water-soluble polymers [pullulan, poly acrylamide, poly(ethylene glycol), and poly(ethylene oxide)] have been investigated and used to categorize separation processes which couple enthalpic and entropic mechanisms. Experiments were carried out with a binary mobile phase which combined a thermodynamically good solvent (water or aqueous 0.02M Na2SO4) and nonsolvent (methanol). The polymer solute was injected in a good solvent. By varying the solvent-nonsolvent ratio in the eluent, conditions could be obtained where the free energies of exclusion and solvation were balanced. This has been given the nomenclature "liquid chromatography under limiting conditions of solubility" (LC-LCS) since the polymer elutes just in front of the system peak at the "limit" of its solubility. Conditions can also be identified where exclusion is balanced with adsorption("liquid chromatography under limiting conditions of adsorption," or LC-LCA). To our knowledge, these are the first experimental reports of LC-LCS for any polymer and the first LC-LCA observation on water-soluble macromolecules. All measurements were carried out over a poly(hydroxymethylacrylate) sorbent. Cloud point curves were found to generally distinguish the regions where LC-LCA or LC-LCS dominate. The data illustrate the need to consider the polymer when analyzing LC-LCA. Conversely, polymer adsorption may play an important role in LC-LCS. (C) 1998 John Wiley & Sons, Inc. [References: 13]
机译：已经研究了四种水溶性聚合物的液相色谱法（普鲁兰聚糖，聚丙烯酰胺，聚乙二醇和聚环氧乙烷），并将其用于分离耦合焓和熵机制的分离过程。用二元流动相进行实验，该流动相结合了热力学良好的溶剂（水或0.02M Na2SO4水溶液）和非溶剂（甲醇）。将聚合物溶质注入良好的溶剂中。通过改变洗脱液中溶剂与非溶剂的比例，可以获得平衡排阻和溶剂化自由能的条件。由于聚合物在其溶解度的“极限”处刚好在系统峰的前面洗脱，因此命名为“在有限的溶解度条件下的液相色谱法”（LC-LCS）。还可以确定排除条件与吸附平衡的条件（“在限制吸附条件下的液相色谱”或LC-LCA）。据我们所知，这是任何聚合物的LC-LCS的第一个实验报告，也是水溶性大分子的第一个LC-LCA观察结果。所有测量均在聚（丙烯酸羟甲基酯）吸附剂上进行。发现浊点曲线通常可以区分LC-LCA或LC-LCS占主导地位的区域。数据说明在分析LC-LCA时​​需要考虑聚合物。相反，聚合物吸附可能在LC-LCS中起重要作用。 （C）1998 John Wiley＆Sons，Inc. [参考：13]

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