Solubility of highly charged anionic polyelectrolytes in presence of multivalent cations: Specific interaction effect
作者:I. Sabbagh、M. Delsanti
DOI:10.1007/s101890050009
日期:2000.1.1
Studies performed on strong polyelectrolytes and on a weak polyelectrolyte, sodium poly(acrylate), show that their stability in presence of multivalent cations depends on the chemical nature of the charged side groups of the polymer. For sulfonate groups (SO3-) or sulfate groups (OSO3-) phase separation generally occurs in presence of inorganic cations of valency 3 (as La3+) or larger and a resolubilization
对强聚电解质和弱聚电解质聚丙烯酸酯钠进行的研究表明,它们在多价阳离子存在下的稳定性取决于聚合物带电侧基的化学性质。为磺酸酯基团(SO 3 - )或硫酸盐基团(OSO 3 - )相分离通常发生在3价的无机阳离子的存在下(如拉3+)或更大和再增发生在高盐浓度。聚电解质与多价阳离子的相互作用是静电起源的,并且相图弱地取决于聚合物主链的化学性质和抗衡离子的特异性。对于丙烯酸酯基团,(COO -),在高盐浓度下,当化合价为2或更高价的无机阳离子(Ca 2+)更大时,观察到相分离。相分离是由于同一链的两个相邻单体的阳离子与丙烯酸酯基团之间的化学缔合。这种化学缔合通过使单体和阳离子脱水而形成疏水复合物。与有机三价阳离子,如亚精胺+ ħ 3 N(CH 2)4 NH 2 +(CH 2)3 NH 3 +,其中没有化学协会与带电侧基发生COO -或SO 3 - 对于该聚电解质,无论在高三价阳离子浓度下具有再溶解的聚电解质,都观察到相似的相图。