Jump to main content
Jump to site search

Issue 40, 2014
Previous Article Next Article

Quantitative mechanical analysis of thin compressible polymer monolayers on oxide surfaces

Author affiliations

Abstract

A clear understanding of the mechanical behavior of nanometer thick films on nanostructures, as well as developing versatile approaches to characterize their mechanical properties, are of great importance and may serve as the foundation for understanding and controlling molecular interactions at the interface of nanostructures. Here we report on the synthesis of thin, compressible polyethylene glycol (PEG) monolayers with a wet thickness of <20 nm on tin dioxide (SnO2) nanofibers through silane-based chemistries. Nanomechanical properties of such thin PEG films were extensively investigated using atomic force microscopy (AFM). In addition, tip–sample interactions were carefully studied, with different AFM tip modifications (i.e., hydrophilic and hydrophobic) and in different ionic solutions. We find that the steric forces dominate the tip–sample interactions when the polymer film is immersed in solution with salt concentrations similar to biological media (e.g., 1× phosphate buffer solution), while van der Waals and electrostatic forces have minimal contributions. A Dimitriadis thin film polymer compression model shows that the linear elastic regime is reproducible in the initial 50% indentation of these films which have tunable Young's moduli ranging from 5 MPa for the low molecular weight films to 700 kPa for the high molecular weight PEG films. Results are compared with the same PEG films deposited on silicon substrates which helped quantify the structural properties and understand the relationship between the structural and the mechanical properties of PEG films on the SnO2 fibers.

Graphical abstract: Quantitative mechanical analysis of thin compressible polymer monolayers on oxide surfaces

Back to tab navigation

Supplementary files

Publication details

The article was received on 12 Jul 2014, accepted on 13 Aug 2014 and first published on 13 Aug 2014


Article type: Paper
DOI: 10.1039/C4SM01530D
Author version
available:
Download author version (PDF)
Soft Matter, 2014,10, 8001-8010
  • Open access: Creative Commons BY license
  •   Request permissions

    Quantitative mechanical analysis of thin compressible polymer monolayers on oxide surfaces

    Q. Huang, I. Yoon, J. Villanueva, K. Kim and D. J. Sirbuly, Soft Matter, 2014, 10, 8001
    DOI: 10.1039/C4SM01530D

    This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements