Adsorption of polyelectrolytes to like-charged substrates induced by multivalent counterions as exemplified by poly(styrene sulfonate) and silica.
Adsorption of polyelectrolytes to like-charged substrates induced by multivalent counterions as exemplified by poly(styrene sulfonate) and silica.
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由多价抗衡离子引起的聚电解质对带相同电荷的基质的吸附，例如聚（苯乙烯磺酸盐）和二氧化硅。
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
M. Borkovec
中科院分区：
文献类型：
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作者：
A. Tiraferri;P. Maroni;M. Borkovec
本研究表明，多价反离子引发聚电解质在等电荷底物上的吸附。用光学反射率法研究了在氯化钠、氯化镁和三氯化镧溶液中，聚苯乙烯磺酸盐在二氧化硅上的吸附。当存在Na(+)时，吸附可以忽略不计，而当存在Mg(2+)和La(3+)时，聚电解质发生吸附。聚电解质的吸附量作为盐浓度的函数经历最大值。这一最大值随着价态的增加而增加，并向较低的盐浓度移动。在低盐浓度下，吸附作用可以忽略不计。在中盐水平，成熟化和多层形成导致了吸附层的持续生长。在较高的盐度下，堵塞和单层的形成导致饱和。这些结果被初步解释为聚电解质-金属络合物的电荷反转。聚电解质的分子质量对吸附行为有重要影响，分子质量越大，其成熟趋势越明显。
The present study demonstrates that multivalent counterions trigger adsorption of polyelectrolytes on a like-charged substrate. In particular, adsorption of polystyrene sulfonate on silica is studied experimentally in NaCl, MgCl2, and LaCl3 solutions by optical reflectivity. While adsorption is negligible in the presence of Na(+), the polyelectrolyte adsorbs in the presence of Mg(2+) and La(3+). The adsorbed amount of the polyelectrolyte goes through a maximum as a function of the salt concentration. This maximum increases with increasing valence and shifts to lower salt concentrations. At low salt concentration, the adsorption is negligible. At intermediate salt level, ripening and multilayer formation leads to continuous growth of the adsorbed layer. At higher salt level, blocking and formation of a monolayer lead to saturation. These results are tentatively interpreted in terms of a charge reversal of the polyelectrolyte-metal complex. The molecular mass of the polyelectrolyte has an important effect on the adsorption behavior, whereby the tendency towards ripening becomes more pronounced at large molecular mass.
影响因子：
5.6
作者：
Rivetti, C;Guthold, M;Bustamante, C
通讯作者：
Bustamante, C