Adsorption Kinetics of Polyelectrolyte onto Monolayers

聚电解质在单分子层上的吸附动力学

基本信息

批准号：
01470101
负责人：
MIYANO Kenjiro
金额：
$ 4.16万
依托单位：
The University of Tokyo, Faculty of Engineering
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01470101/
关键词：
Polyion comprex ATR method Monolayer Electrostatic absorption LB film ポリマ-吸着

项目摘要

The adsorption kinetics of an electrolyte polymer onto a monolayer spread on the solution has been studied by means of the attenuated total reflection (ATR) method. The polymer was PSSK (potassium poly-(Stylenesulfonate) : anion) and the monolayer DOAB (dioctadecyl-dimethyl-ammonium-bromide : cation). A glass prism (SFS-1 glass) whose hypotenuse surface was coated with a thin (-500 A) Ag film was pressed onto a monolayer of DOAB spread on pure water. The ATR signal caused by the SPP (surface plasmon polariton) at the Ag/monolayer interface was monitored. The subphase water was then slowly replaced with the polymer solution of varing concentration. The shift of the ATR dip indicates the thickness of the polymer adsorbed onto the monolayer and the width signals the inhomogeneity of the polyemer layer. We found that the adsorption occurred in two steps ; first the adsorbed layer was monomolecular (thickness - 5A), then it grew into a thick and inhomogeneous film. The initial layer thickness was independent of the molecular weight of the polymer. The final thickness, however, depended on the molecular weight weakly (d=16A for n=3500 and d=33A for n=42000, where n is the degree of polymerization) suggesting loops and tails in the film at this stage. We also found that the adsorption was completely absent onto a non-cationic monolayer (stearic acid) within the resolution of our method. CONCLUSION : The polymer adsorption onto a spread monolayer is completely governed by the charge nutrality (at least in the early stage of the adsorption) and a 1 : 1 polyion complex is indeed formed at the solution/monolayer interface as has long been speculated.

已经通过减弱的总反射（ATR）方法研究了电解质聚合物在单层上传播的单层的吸附动力学。聚合物是PSSK（钾硫磺酸盐）：阴离子）和单层doab（二二甲苯二甲基 - 二甲基 - 氨溴化物：阳离子）。玻璃棱镜（SFS-1玻璃）的斜边表面涂有薄（-500 A）Ag膜的涂层，将其按在纯净水上的Doab的单层上。监测由Ag/单层界面处的SPP（表面等离激元极化）引起的ATR信号。然后将亚相水缓慢地用差分浓度的聚合物溶液代替。 ATR倾角的移位表明聚合物的厚度吸附到单层上，并且宽度信号信号是polyemer层的不均匀性。我们发现吸附分为两个步骤。首先，吸附的层是单分子（厚度-5a），然后成长为厚而不均匀的膜。初始层厚度与聚合物的分子量无关。然而，最终厚度取决于分子量弱（n = 3500的d = 16a，n = 42000的d = 33a，其中n是聚合的程度）表明，在此阶段，膜中的循环和尾巴。我们还发现，在我们方法的分辨率中，完全没有吸附在非阳离子单层（硬脂酸）上。结论：在扩散单层上的聚合物吸附完全受电荷营养（至少在吸附的早期阶段）的控制，并且确实在溶液/单层界面上确实形成了1：1 Polyion络合物，这是长期以来推测的。