Studies on interaction between similarly charged polyelectrolyte: Fatty acid system
Studies on interaction between similarly charged polyelectrolyte: Fatty acid system
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相似电荷聚电解质之间相互作用的研究：脂肪酸体系
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
D. Langevin
中科院分区：
文献类型：
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作者：
A. Gole;S. Phadtare;M. Sastry;D. Langevin
研究了阴离子聚电解质聚丙烯酰胺甲基丙磺酸盐（PAMPS）与阴离子脂肪酸花生酸（AA）在空气-水界面的相互作用。虽然带类似的电荷，但与AA单层的多电解质复合物可能是由除静电外的相互作用驱动的，如疏水和氢键。通过在盐、低pH值或中性表面活性分子（如十八醇（ODO））的存在下进行实验，证明了聚合物和脂肪酸之间没有静电相互作用。还研究了聚合物电荷密度对其与单分子层的相互作用/络合程度的影响。络合的程度取决于聚合物上的净电荷，并随着电荷的减少而增加。为了进一步补充非静电相互作用的作用，我们通过表面张力测量研究了PAMPS与阴离子表面活性剂二辛基磺基琥珀酸酯（AOT）的相互作用。在较低的聚合物浓度下，我们观察到临界聚集浓度（CAC）的存在，这是相互作用系统的典型特征。对聚合物与AA的络合反应进行了表面压力-面积（π-A）等温线和布鲁斯特角显微镜（BAM）分析。试图形成Langmuir-Blodgett （LB）膜的配合物并没有产生任何层状层的逐层堆叠，可能是由于聚合物的体积和所使用的相互作用的性质。石英晶体微重法（QCM）和傅里叶变换红外光谱法（FTIR）已经被用来表征这种薄膜。
Interaction between an anionic polyelectrolyte, poly(acrylamido)methylpropanesulfonate (PAMPS), and anionic fatty acid, arachidic acid (AA), has been studied at the air-water interface. Although similarly charged, the polyelectrolyte complexes with the AA monolayer are possibly driven by interactions other than electrostatic, such as hydrophobic and hydrogen bonding. The absence of electrostatic interaction between the polymer and the fatty acid was demonstrated by performing the experiments in the presence of salt, at low pH, or with a neutral surface-active molecule such as octadecanol (ODO). The effect of polymer charge density on its interaction/degree of complexation with the monolayer has also been investigated. The degree of complexation depends on the net charge on the polymer and increases with the decrease in the charge. To further supplement the role of nonelectrostatic interactions, we have studied the interaction of PAMPS with an anionic surfactant, dioctyl sulfosuccinate (AOT), by surface tension measurements. At lower polymer concentrations, we observe the presence of a critical aggregation concentration (CAC), which is typical for interacting systems. The complexation of polymer with AA has been followed by surface pressure-area (π-A) isotherms and Brewster angle microscopy (BAM). Attempts to form Langmuir-Blodgett (LB) films of the complexes did not yield any lamellar layer by layer stacking, possibly due to the bulkiness of the polymer and the nature of the interactions used. Quartz crystal microgravimetry (QCM) and Fourier transform infrared spectroscopy (FTIR) have been used to characterize such films.