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Solution Properties of Intramolecularly Crosslinked Polyelectrolyte.

分子内交联聚电解质的溶液性质。

基本信息

批准号：
02650652
负责人：
OCHIAI Hiroshi
金额：
$ 1.22万
依托单位：
Hiroshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

项目摘要

The present study was carried out to clarify the mutual interaction in the polymer solution from view point of the intrachain crosslinks, polyelectrolyte, and interaction among counterions.About an interesting polyelectrolyte solution behabior observed in aqueous poly(vinyl alcohol)(PVA)/Borax(Na_2B_4O_7) systems, the following experimental facts were revealed : 1, complexations(mono-diol and di-diol) of PVA with borate ion, B(OH)_4^-, which introduce simultaneously the charges and crosslinks to the PVA chain, occur only intramolecularly, being unchanged the molecular weight of PVA. 2, the formation constants of both complexes decrease sharply with borax concentration C_b and this decrease levels off at higher C_b, as well as the second virial coefficient does.These results can well interpret the polyelectrolyte behaviorof PVA/Borax systems in terms of a favorable balance between expansion due to charges and contraction due to intrachain crosslinks in the complexed PVA. Also, the mutual charge repulsion between the complexing borate ion and the charges on the complexed PVA chain depresses strongly a further complexation onto the PVA chain.In relation to the above-polyelectrolyte solution behavior, we found also that a relatively small hydrophobic ion(ethylbenzensulfonate anion), which has not self-association ability itself, can associate each other around a polyion(poly(allylammonium)cation)through its hydrophobic interaction.

本研究从链内交联、聚电解质和反离子相互作用等方面阐明了聚合物溶液中的相互作用。在聚乙烯醇(PVA)/硼砂（Na_2B_4O_7）水溶液体系中观察到一个有趣的聚电解质溶液行为，揭示了以下实验事实：1、PVA与硼酸盐离子B(OH)_4^-的络合作用（单二醇和双二醇），在PVA链上同时引入电荷和交联，仅发生在分子内，而PVA的分子量不变。2、两种配合物的形成常数随硼砂浓度C_b急剧下降，且在较高的C_b时下降趋于平稳，第二维里系数也是如此。这些结果可以很好地解释PVA/硼砂体系的聚电解质行为，因为在络合的PVA中，电荷引起的膨胀和链内交联引起的收缩之间存在良好的平衡。此外，配合硼酸盐离子与配合的PVA链上的电荷之间的相互电荷排斥强烈地抑制了进一步的配合到PVA链上。对于上述聚电解质溶液的行为，我们还发现一个相对较小的疏水离子（乙基苯磺酸阴离子），其本身没有自缔合能力，可以通过其疏水相互作用在聚离子（聚（烯丙基铵）阳离子）周围相互缔合。