PH, SALT, AND BUFFER DEPENDENT SWELLING IN IONIZABLE COPOLYMER GELS - TESTS OF THE IDEAL DONNAN EQUILIBRIUM-THEORY
PH, SALT, AND BUFFER DEPENDENT SWELLING IN IONIZABLE COPOLYMER GELS - TESTS OF THE IDEAL DONNAN EQUILIBRIUM-THEORY
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DOI：
10.1163/156856294x00130
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发表时间：
1994-01-01
影响因子：
3.6
通讯作者：
SIEGEL, RA
中科院分区：
文献类型：
--
作者：
FIRESTONE, BA;SIEGEL, RA
我们提出的可电离的共聚物凝胶，甲基丙烯酸甲酯/N，N-二甲基氨基乙基甲基丙烯酸酯70/30摩尔%，在缓冲和非缓冲电解质溶液中的平衡溶胀研究的结果。实验条件的设计，以证明在电离凝胶的外部溶液的电解质组合物的溶胀的敏感性。在一般情况下，凝胶溶胀作为溶液离子强度的函数被证明是高度非单调的，是特别敏感的化合价和溶液中存在的离子的浓度。对理想唐南平衡理论的严格检验表明，后者不能以自洽的方式解释所有的数据。然而，基于理想唐南理论的启发式程序可以定性地预测所观察到的趋势。虽然不是定量的，这种启发式的方法提供了相当深入的机制，在各种溶液条件下的溶胀行为。非理想行为的可能原因进行了讨论，并报告和讨论了一些观察到的特定离子效应。
We present results of equilibrium swelling studies of the ionizable copolymer gel, methyl methacrylate/N,N-dimethylaminoethyl methacrylate 70/30 mol%, in buffered and unbuffered electrolyte solutions. The experimental conditions were designed to demonstrate the sensitivity of swelling in ionized gels to the electrolyte composition of the external solution. In general, gel swelling as a function of solution ionic strength is shown to be highly nonmonotonic and is particularly sensitive to the valence and concentrations of ions present in solution. A rigorous test of ideal Donnan equilibrium theory shows that the latter is unable to explain all the data in a self-consistent manner. However, a heuristic procedure based on the ideal Donnan theory can predict qualitatively the observed trends. While not quantitative, this heuristic approach provides considerable insight into the mechanisms underlying the swelling behavior under various solution conditions. Possible causes of nonideal behavior are discussed, and some observed specific ion effects are reported and discussed.