POLYELECTROLYTE GELS IN SALT SOLUTIONS
POLYELECTROLYTE GELS IN SALT SOLUTIONS
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DOI：
10.1002/pol.1955.120157906
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发表时间：
1955-01-01
影响因子：
3.4
通讯作者：
MICHAELI, I
中科院分区：
文献类型：
--
作者：
KATCHALSKY, A;MICHAELI, I
将大多数经典的亲水凝胶和许多离子交换剂作为多电解质体系来处理是有利的。因此，明胶、果胶和琼脂凝胶以及合成的低交联度离子交换剂可被认为是聚电解质凝胶。虽然对这些系统进行了大量的实验研究，但结果还没有被一个一般的理论所综合。虽然宝洁和威尔逊的经典理论在解释凝胶行为方面起到了很好的指导作用，但它是基于一个模型的，当用于描述高电荷的聚电解质系统时，它过于简化了。由于缺乏足够的理论，只能用经验方程来描述聚电解质凝胶的基本性质，如收缩压力或小离子的活性因子。因此，Gl~ eckauf,~ D~ ncan，~和Davies和Yeoman5将这些体系视为简单的电解质溶液，并使用Harned规则计算凝胶相中小离子的活度因子。此外，这些作者允许凝胶收缩性对Donnan分布的影响，以Gregor提出的方式，6使用从实验中得出的收缩压力值。然而，对聚电解质凝胶性质的完整理论推导（一般来说）应该明确地包括聚合物的未来电荷所贡献的静电能和凝胶网络的弹性能。前一个因素在聚电解质溶液中得到了广泛的研究^，而后一个因素在非极性凝胶中得到了成功的处理。本文提出了高度膨胀的聚电解质凝胶的一般理论，该理论结合了聚电解质溶液的自由能方程和非极性网络的自由能方程。该理论是基于Katchalsky、Lifson和Ei~ enberg的治疗方法。由于在他们的简短说明中没有给出详细的计算，他们的处理，适用于凝胶在无盐水中膨胀的特殊情况，将在这里更充分地介绍。然后对聚电解质凝胶在盐溶液中的作用进行理论分析，计算值为com-
It is advantageous to treat most of the classical liydrophilic gels and many ion exchangers as polyelectrolyte systems. Thus gelatin, jellies of pectin and agar, as well as synthetic ion exchangers of low degree of crosslinking, may be considered as polyelectrolyte gels. Although numerous experimental investigations of these systems have been carried out, l the results have not been integrated by a general theory. While the classical theory of Procter and Wilson2 served well as a guide in the explanation of gel behavior, it is based on a model which is oversimplified when used in describing highly charged polyelectrolyte systems. For lack of an adequate theory, empirical equations had to be used to describe such fundamental properties of polyelectrolyte gels as the contractile pressure, or the activity factors of the small ions. Thus Gl~ eckauf,~ D~ ncan,~ and Davies and Yeoman5 treated these systems as simple electrolyte solutions and used the Harned rule to calculate the activity factors of the small ions in the gel phase. In addition, these authors allowed for the effect of gel contractility on the Donnan distribution, in a manner proposed by Gregor, 6 using for the contractile pressure values derived from experiment. However, a full theoretical derivation of the properties of polyelectrolyte gels (in general) should include, explicitly, both the electrostatic energy contributed by the fured charges of the polymer and the elastic energy of the gel network. The former factor has been extensively studied in polyelectrolyte solution^,^ while the latter has been successfully treated in the case of nonpolar gels. 8This paper presents a general theory of highly swollen polyelectrolyte gels which combines the equations for the free energy of polyelectrolyte solutions and those for the free energy of a nonpolar network. The theory is based on the treatment of Katchalsky, Lifson, and Ei~ enberg.~ As no detailed calculations were given in their short note, their treatment, as applied to the special case of swelling of gels in salt-free water, will be presented here more fully. A theoretical analysis of polyelectrolyte gels in salt solutions will then be presented, and the calculated values will be com-