Comparison of the structure of polyelectrolyte multilayer films exhibiting a linear and an exponential growth regime: An in situ atomic force microscopy study
Comparison of the structure of polyelectrolyte multilayer films exhibiting a linear and an exponential growth regime: An in situ atomic force microscopy study
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DOI：
10.1021/ma0119833
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发表时间：
2002-05-21
期刊：
影响因子：
5.5
通讯作者：
Picart, C
中科院分区：
文献类型：
--
作者：
Lavalle, P;Gergely, C;Picart, C
我们在此报告由聚（L-谷氨酸）和聚（L-赖氨酸）（PGA/PLL）形成的聚电解质多层膜的结构表征。通过原位原子力显微镜（ATM）和光波导光模式光谱（OWLS）将该系统的生长与聚（苯乙烯磺酸）/聚（烯丙胺盐酸盐）（PSS/PAH）多层的生长进行比较。与随沉积层对 i 的数量线性增长的 (PSS/PAH)(i) 薄膜相反，光学数据证明 (PGA/PLL)(i) 薄膜具有指数增长的特征。 (PSS/PAH)(i) 薄膜的结构分析揭示了被小球覆盖的光滑无特征表面。另一方面，(PGA/PLL)(i) 薄膜形成具有蠕虫状图案的延伸结构。我们提出了一种基于聚电解质扩散进出薄膜以及在薄膜表面形成聚阴离子/聚阳离子复合物的新生长机制，以解释整个结果。
We report here on the structural characterization of polyelectrolytes multilayer films formed by poly(L-glutamic acid) and poly(L-lysine) (PGA/PLL). The growth of this system is compared to that of poly(styrenesulfonate)/poly(allylamine hydrochloride) (PSS/PAH) multilayers by means of in situ atomic force microscopy (ATM) and by optical waveguide lightmode spectroscopy (OWLS). In contrary to the (PSS/PAH)(i) films that are growing linearly with the number of deposited layer pairs i, optical data evidenced that the (PGA/PLL)(i) films are characterized by an exponential growth. The analysis of the structure of the (PSS/PAH)(i) films reveals a smooth featureless surface covered by small globules. On the other hand, (PGA/PLL)(i) films form extended structures that appear with a vermiculate pattern. We propose a new growth mechanism based on polyelectrolyte diffusion in and out of the film coupled to the formation of polyanion/polycation complexes at the surface of the film in order to explain the whole results.