Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-26T04:50:33.089Z Has data issue: false hasContentIssue false
  • English
  • Français

The mechanical properties of a surface-modified layer on polydimethylsiloxane

Published online by Cambridge University Press:  31 January 2011

K.L. Mills ,
Xiaoyue Zhu ,
Shuichi Takayama  and
M.D. Thouless
K.L. Mills
Affiliation:
Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109
Xiaoyue Zhu
Affiliation:
Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109
Shuichi Takayama
Affiliation:
Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109; and Macromolecular Science and Engineering Program, University of Michigan, Ann Arbor, Michigan 48109
M.D. Thouless*
Affiliation:
Departments of Mechanical Engineering and Materials Science & Engineering, University of Michigan, Ann Arbor, Michigan 48109
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Surface modification of the elastomer polydimethylsiloxane (PDMS) by exposure to oxygen plasma for four minutes creates a thin, stiff film. In this study, the thickness and mechanical properties of this surface-modified layer were determined. Using the phase image capabilities of a tapping-mode atomic force microscope (AFM), the surface-modified region was distinguished from the bulk PDMS; specifically, it suggested a graded surface layer to a depth of about 200 nm. Load-displacement data for elastic indentation using a compliant AFM cantilever was analyzed as a plate bending on an elastic foundation to determine the elastic modulus of the surface (37 MPa). An applied uniaxial strain generated a series of parallel nanocracks with spacing on the order of a few microns. Numerical analyses of this cracking phenomenon showed that the depth of these cracks was in the range of 300–600 nm and that the surface layer was extremely brittle, with toughness in the range of 0.1– 0.3 J/m2.

Keywords

Elastic propertiesNanoscaleThin film
Type
Articles
Information
Journal of Materials Research , Volume 23 , Issue 1 , January 2008 , pp. 37 - 48
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Lotters, J.C., Olthuis, W., Veltink, P.H.Bergveld, P.: The mechanical properties of the rubber elastic polymer polydimethylsiloxane for sensor applications. J. Micromech. Microeng. 7, 145 1997CrossRefGoogle Scholar
2Bietsch, A.Michel, B.: Conformal contact and pattern stability of stamps used for soft lithography. J. Appl. Phys. 88, 4310 2000CrossRefGoogle Scholar
3Kumar, A., Biebuyck, H.A.Whitesides, G.M.: Patterning self-assembled monolayers: Applications in materials science. Langmuir 10, 1498 1994CrossRefGoogle Scholar
4Duffy, D.C., McDonald, J.C., Schueller, O.J.A.Whitesides, G.M.: Rapid prototyping of microfluidic systems in poly(dimethlysiloxane). Anal. Chem. 70, 4974 1998CrossRefGoogle Scholar
5Gu, W., Zhu, X.Y., Futai, N., Cho, B.S.Takayama, S.: Computerized microfluidic cell culture using elastomeric channels and Braille displays. Proc. Natl. Acad. Sci. U.S.A. 101, 15861 2004CrossRefGoogle ScholarPubMed
6Unger, M.A., Chou, H-P., Thorsen, T., Scherer, A.Quake, S.R.: Monolithic microfabricated valves and pumps by multilayer soft lithography. Science 288, 113 2000CrossRefGoogle ScholarPubMed
7Fritz, J.L.Owen, M.J.: Hydrophobic recovery of plasma-treated polydimethylsiloxane. J. Adhes. 54, 33 1995CrossRefGoogle Scholar
8Hillborg, H.Gedde, U.W.: Hydrophobicity changes in silicone rubbers. IEEE Trans. Dielectr. Electr. Insul. 6, 703 1999CrossRefGoogle Scholar
9Bowden, N., Huck, W.T.S., Paul, K.E.Whitesides, G.M.: The controlled formation of ordered, sinusoidal structures by plasma oxidation of an elastomeric polymer. Appl. Phys. Lett. 75, 2557 1999CrossRefGoogle Scholar
10Efimenko, K., Rackaitis, M., Manias, E., Vaziri, A., Mahadevan, L.Genzer, J.: Nested self-similar wrinkling patterns in skins. Nat. Mater. 4, 293 2005CrossRefGoogle ScholarPubMed
11Hillborg, H., Ankner, J.F., Gedde, U.W., Smith, G.D., Yasuda, H.K.Wikstrom, K.: Crosslinked polydimethylsiloxane exposed to oxygen plasma studied by neutron reflectometry and other surface specific techniques. Polymer 41, 6851 2000CrossRefGoogle Scholar
12Zhu, X.Y., Mills, K.L., Peters, P.R., Bahng, J.H., Liu, E.H., Shim, J., Naruse, K., Csete, M.E., Thouless, M.D.Takayama, S.: Fabrication of reconfigurable protein matrices by cracking. Nat. Mater. 4, 403 2005CrossRefGoogle ScholarPubMed
13Huh, D., Mills, K.L., Zhu, X., Burns, M.A., Thouless, M.D.Takayama, S.: Tuneable elastomeric nanochannels for nanofluidic manipulation. Nat. Mater., 6, 424 2007CrossRefGoogle ScholarPubMed
14Hillborg, H., Tomczak, N., Olah, A., Schonherr, H.Vancso, G.J.: Nanoscale hydrophobic recovery: A chemical force microscopy study of UV/ozone-treated cross-linked poly(dimethylsiloxane). Langmuir 20, 785 2004CrossRefGoogle ScholarPubMed
15Bhattacharya, A.K.Nix, W.D.: Analysis of elastic and plastic-deformation associated with indentation testing of thin-films on substrates. Int. J. Solids Struct. 24, 1287 1988CrossRefGoogle Scholar
16Saha, R.Nix, W.D.: Effects of the substrate on the determination of thin film mechanical properties by nanoindentation. Acta Mater. 50, 23 2002CrossRefGoogle Scholar
17ASTM: ASTM D 624-00: Standard test method for tear strength of conventional vulcanized rubber and thermoplastic elastomers ASTM International Warrendale, PA 2000Google Scholar
18ASTM: ASTM D 5045-99: Standard test methods for plane-strain fracture toughness and strain energy release rate of plastic materials ASTM International Warrendale, PA 1999Google Scholar
19Whitesides, G.M., Ostuni, E., Takayama, S., Jiang, X.Y.Ingber, D.E.: Soft lithography in biology and biochemistry. Annu. Rev. Biomed. Eng. 3, 335 2001CrossRefGoogle ScholarPubMed
20Morra, M., Occhiello, E., Marola, R., Garbassi, F., Humphrey, P.Johnson, D.: On the aging of oxygen plasma-treated polydimethylsiloxane surfaces. J. Colloid Interface Sci. 137, 11 1990CrossRefGoogle Scholar
21Tóth, A., Bertóti, I., Blazsó, M., Bánhegyi, G., Bognar, A.Szaplonczay, P.: Oxidative damage and recovery of silicone rubber surfaces: I. X-ray photoelectron spectroscopic study. J. Appl. Polym. Sci. 52, 1293 1994CrossRefGoogle Scholar
22Bar, G., Delineau, L., Hafele, A.Whangbo, M-H.: Investigation of the stiffness change in, the indentation force and the hydrophobic recovery of plama-oxidized polydimethylsiloxane surfaces by tapping mode atomic force microscopy. Polymer 42, 3627 2001CrossRefGoogle Scholar
23Veeco Instruments Inc.: MultiMode AFM Application Notes: Phase Imaging; Beyond Topography Veeco Instruments Inc., Santa Barbara, CA 2004Google Scholar
24Clement, F., Lapra, A., Bokobza, L., Monnerie, L.Menez, P.: Atomic force microscopy investigation of filled elastomers and comparison with transmission electron microscopy: Application to silica-filled silicone elastomers. Polymer 42, 6259 2001CrossRefGoogle Scholar
25Magonov, S.N., Elings, V.Whangbo, M-H.: Phase imaging and stiffness in tapping-mode atomic force microscopy. Surf. Sci. 375, L385 1997CrossRefGoogle Scholar
26Mills, K.L., Zhu, X., Lee, D., Takayama, S.Thouless, M.D.: Properties of the surface-modified layer of plasma-oxidized poly(dimethylsiloxane) in Mechanics of Nanoscale Materials and Devices, edited by A. Misra, J.P. Sullivan, H. Huang, K. Lu, and S. Asif (Mater. Res. Soc. Symp. Proc. 924E, Warrendale, PA, 2006), p. 0924-Z07-08CrossRefGoogle Scholar
27Oliver, W.C.Pharr, G.M.: An improved technique for determining hardness and elastic-modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 1992CrossRefGoogle Scholar
28Olshanskii, V.P.: Green’s function for the bending of a plate on an elastic half-space. J. Appl. Math. Mech. 51, 681 1987CrossRefGoogle Scholar
29Allen, H.G.Analysis and Design of Structural Sandwich Panels 1st ed.Pergamon Press Oxford 1969Google Scholar
30Huang, Z.Y., Hong, W.Suo, Z.: Nonlinear analyses of wrinkles in a film bonded to a compliant substrate. J. Mech. Phys. Solids 53, 2101 2005CrossRefGoogle Scholar
31Lee, D., Triantafyllidis, N., Barber, J.R.Thouless, M.D.: Unpublished work 2007Google Scholar
32Thouless, M.D., Olsson, E.Gupta, A.: Cracking of brittle films on elastic substrates. Acta Metall. Mater. 40, 1287 1992CrossRefGoogle Scholar
33Thouless, M.D.: Crack spacing in brittle films on elastic substrates. J. Am. Ceram. Soc. 73, 2144 1990CrossRefGoogle Scholar
34Shenoy, V.B., Schwartzman, A.F.Freund, L.B.: Crack patterns in brittle thin films. Int. J. Fract. 103, 1 2000CrossRefGoogle Scholar
35Mullins, W.W.: Theory of thermal grooving. J. Appl. Phys. 28, 333 1957CrossRefGoogle Scholar
36Thouless, M.D.: Effect of surface-diffusion on the creep of thin-films and sintered arrays of particles. Acta Metall. Mater. 41, 1057 1993CrossRefGoogle Scholar
37Hui, C.Y., Jagota, A., Lin, Y.Y.Kramer, E.J.: Constraints on microcontact printing imposed by stamp deformation. Langmuir 18, 1394 2002CrossRefGoogle Scholar
38Chaudhury, M.K.Whitesides, G.M.: Direct measurement of interfacial interactions between semispherical lenses and flat sheets of poly(dimethylsiloxane) and their chemical derivatives. Langmuir 7, 1013 1991CrossRefGoogle Scholar