Hollow Polyelectrolyte Multilayer Tubes: Mechanical Properties and Shape Changes

详细信息    查看全文

• 作者：Renate Mueller ; Lars Daehne ; Andreas Fery
• 刊名：Journal of Physical Chemistry B
• 出版年：2007
• 出版时间：July 26, 2007
• 年：2007
• 卷：111
• 期：29
• 页码：8547 - 8553
• 全文大小：480K
• 年卷期：v.111,no.29(July 26, 2007)
• ISSN：1520-5207

文摘

In this paper, novel hollow polyelectrolyte multilayer tubes from poly(diallyldimethylammonium chloride)(PDADMAC), poly(styrene sulfonate) (PSS), and poly(allylamine hydrochloride) (PAH) were prepared:Readily available glass fiber templates are coated with polyelectrolytes using the layer-by-layer technique,followed by subsequent fiber dissolution. Depending on the composition of the polymeric multilayer, stablehollow tubes or tubes showing a pearling instability are observed. This instability corresponds to the Rayleighinstability and is a consequence of an increased mobility of the polyelectrolyte chains within the multilayer.The well-defined stable tubes were characterized with fluorescence microscopy, confocal laser scanningmicroscopy, and atomic force microscopy (AFM). The tubes were found to be remarkably free of defects,which results in an impermeable tube wall for even low molecular weight molecules. The mechanical propertiesof the tubes were determined with AFM force spectroscopy in water, and because continuum mechanicalmodels apply, the Young's modulus of the wall material was determined. Additionally, scaling relations forthe dependency of tube stiffness on diameter and wall thickness were validated. Because both parameters canbe experimentally controlled by our approach, the deformability of the tubes can be varied over a broadrange and adjusted for the particular needs.