Polymer brushes atomic force microscopy

Kelly T W ef a/1998 Direct force measurements at polymer brush surfaces by atomic force microscopy Macromoiecuies 31 4297-300... 

The thickness ho of the PDMS films on top of the PDMS brush, as measured by ellipsometry, was varied in the range of 30-150 nm. All films were obtained by spin-coating dilute heptane solutions directly (Mito the coated substrates. As indicated in Fig. 4, isothermal dewetting of the thin polymer films, i.e., the retraction of a contact line, was followed in real time (0 by optical microscopy. The morphology of the rim was also investigated by atomic force microscopy (AFM). More details on sample preparation and dewetting measurements can be found in [146, 147],... 

Ito, Y., Park, Y.S. and Imanishi, Y. 1997b. Imaging of pH-sensitive polymer brush on a porous membrane using atomic force microscopy in aqueous solution. MacromoL o Commm. 18 221-224. 

The thicknesses of monolayers and polymer brushes on the silicon substrates were evaluated as the height difference between the monolayer surface and bared Si-wafer surface by atomic force microscopy (AFM). The thickness of the OTMS monolayer was estimated to be ca. 2.0 nm. An ellipsometer (Imaging Ellipsometer, MORITEX Co., Tokyo) equipped with a YAG (yttrium aluminum garnet) laser (532.8 nm) was also used to determine the thickness of the polymer brushes. 

However, it is also of interest to examine the properties of the brush near the entrance of the pores up to a depth of several nanometers. For such a scope, surface analytical techniques may be implemented for the determination of near-surface composition. Ito et al. [24] have visualized in situ, by atomic force microscopy (AFM), the entrance of brush-coated pores and found a correlation between the observed pore opening and its permeation properties. Also x-ray photoelectron spectroscopy (XPS) was performed [22] on layer-by-layer sputtered dry brush-coated membranes, in order to determine the in-depth distribution of polymer chains. 

Yamamoto, S., Ejaz, M., Tsuji, Y., Matsumoto, M., and Fukuda, T. 2000. Surface Interaction forces of well-defined, high-density polymer brushes studied by atomic force microscopy. 2. Effect of graft density. Macromolecules 33 5608-5612. 

Goodman, D., Kizhakkedathu, J.N., Brooks, D.E. 2004. Attractive Bridging Interactions in Dense Polymer Brushes in Good Solvent Measured by Atomic Force Microscopy, ngjpjiir 20 2333-2340. 

Polydispersity Estimation of Adsorbing Polymer Brushes by Atomic Force Microscopy, 20 3297-3303. 

Surface interaction forces of well-defined, high-density polymer brushes studied by atomic force microscopy. 1. Effect of chain length. 33 ... 

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