PHASE-TRANSITION OF A POLYMER GEL IN PURE AND MIXED-SOLVENT MEDIA
PHASE-TRANSITION OF A POLYMER GEL IN PURE AND MIXED-SOLVENT MEDIA
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DOI：
10.1143/jpsj.56.233
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发表时间：
1987-01-01
影响因子：
1.7
通讯作者：
HIROTSU, S
中科院分区：
文献类型：
--
作者：
HIROTSU, S
实验研究了聚N-异丙基丙烯酰胺(NIPA)凝胶在几种纯溶剂和混合溶剂中的体积相变。在水中加入少量的醇(<；20%)，NIPA在水中的转变由轻微的不连续转变为更明显的一级转变。随着混合溶剂中醇浓度的进一步增加，体积转变变得模糊并最终消失。根据聚合物溶液平均场理论对实验结果进行了分析，结果表明，聚合物-溶剂相互作用参数χ在体积转变时发生了剧烈的变化。这表明溶液的焓和熵强烈地依赖于聚合物的浓度。
A volume phase transition of poly-N-isopropylacrylamide (NIPA) gel immersed in some pure and mixed solvents has been investigated experimentally. A slightly discontinuous transition of NIPA get in water changed to a more distinctly first-order transition on adding a small amount (<20%) of alcohols to water. As the concentration of alcohols in the mixed solvent increased further, the volume transition blurred and eventually disappeared. Analyzing the experimental results on the basis of the mean field theory of polymer solution, it has been shown that the polymer-solvent interaction parameter χ exhibits a drastic change at the volume transitions. This indicates that the enthalpy and entropy of solution depend strongly on polymer concentration.