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Physical ageing of the contact line on colloidal particles at liquid interfaces

Nature Materials volume 11, pages 138–142 (2012)Cite this article

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Abstract

Young’s law1 predicts that a colloidal sphere in equilibrium with a liquid interface will straddle the two fluids, its height above the interface defined by an equilibrium contact angle2. This has been used to explain why colloids often bind to liquid interfaces3,4, and has been exploited in emulsification5, water purification6, mineral recovery7, encapsulation8 and the making of nanostructured materials9,10. However, little is known about the dynamics of binding. Here we show that the adsorption of polystyrene microspheres to a water/oil interface is characterized by a sudden breach and an unexpectedly slow relaxation. The relaxation appears logarithmic in time, indicating that complete equilibration may take months. Surprisingly, viscous dissipation appears to play little role. Instead, the observed dynamics, which bear strong resemblance to ageing in glassy systems, agree well with a model describing activated hopping of the contact line over nanoscale surface heterogeneities. These results may provide clues to longstanding questions on colloidal interactions at an interface11,12.

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Figure 1: Holographic microscopy reveals the dynamics of particles approaching and breaching an interface.
Figure 2: A dynamic wetting model explains the long relaxation and logarithmic dynamics.
Figure 3: The particle surface controls the rate of relaxation.

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References

  1. Young, T. An essay on the cohesion of fluids. Phil. Trans. R. Soc. Lond. 95, 65–87 (1805).

    Article  Google Scholar 

  2. Binks, B. Colloidal particles at liquid interfaces. Phys. Chem. Chem. Phys. 9, 6298–6299 (2007).

    Article  CAS  Google Scholar 

  3. Ramsden, W. Separation of solids in the surface-layers of solutions and ‘suspensions’ (Observations on surface-membranes, bubbles, emulsions, and mechanical coagulation). Proc. R. Soc. Lond. 72, 156–164 (1903).

    CAS  Google Scholar 

  4. Pickering, S. U. Emulsions. J. Chem. Soc. 91, 2001–2021 (1907).

    Article  Google Scholar 

  5. Aveyard, R., Binks, B. P. & Clint, J. H. Emulsions stabilised solely by colloidal particles. Adv. Colloid Interface Sci. 100–102, 503–546 (2003).

    Article  Google Scholar 

  6. Nguyen, A., Pugh, R. J. & Jameson, G. J. Colloidal Particles at Liquid Interfaces (Cambridge Univ. Press, 2006).

    Google Scholar 

  7. Bhargava, A., Francis, A. V. & Biswas, A. K. Interfacial studies related to the recovery of mineral slimes in a water–hydrocarbon liquid-collector system. J. Colloid Interface Sci. 64, 214–227 (1978).

    Article  CAS  Google Scholar 

  8. Dinsmore, A. et al. Colloidosomes: Selectively permeable capsules composed of colloidal particles. Science 298, 1006–1009 (2002).

    Article  CAS  Google Scholar 

  9. Velikov, K. P. & Velev, O. D. Colloidal Particles at Liquid Interfaces (Cambridge Univ. Press, 2006).

    Google Scholar 

  10. McGorty, R., Fung, J., Kaz, D. & Manoharan, V. N. Colloidal self-assembly at an interface. Mater. Today 13, 34–42 (June, 2010).

    Article  CAS  Google Scholar 

  11. Park, B. J. et al. Direct measurements of the effects of salt and surfactant on interaction forces between colloidal particles at water–oil interfaces. Langmuir 24, 1686–1694 (2008).

    Article  CAS  Google Scholar 

  12. Nikolaides, M. et al. Electric-field-induced capillary attraction between like-charged particles at liquid interfaces. Nature 420, 299–301 (2002).

    Article  CAS  Google Scholar 

  13. Seveno, D. et al. Dynamics of wetting revisited. Langmuir 25, 13034–13044 (2009).

    Article  CAS  Google Scholar 

  14. Redon, C., Brochard-Wyart, F. & Rondelez, F. Dynamics of dewetting. Phys. Rev. Lett. 66, 715–718 (1991).

    Article  CAS  Google Scholar 

  15. Dagastine, R. R. & White, L. R. Forces between a rigid probe particle and a liquid interface II. The general case. J. Colloid Interface Sci. 247, 310–320 (2002).

    Article  CAS  Google Scholar 

  16. Ally, J., Kappl, M., Butt, H. & Amirfazli, A. Detachment force of particles from air–liquid interfaces of films and bubbles. Langmuir 26, 18135–18143 (2010).

    Article  CAS  Google Scholar 

  17. Lee, S. et al. Characterizing and tracking single colloidal particles with video holographic microscopy. Opt. Express 15, 18275–18282 (2007).

    Article  Google Scholar 

  18. Park, B. J. & Furst, E. M. Optical trapping forces for colloids at the oil–water interface. Langmuir 24, 13383–13392 (2008).

    Article  CAS  Google Scholar 

  19. Mbamala, E. & von Grunberg, H. Effective interaction of a charged colloidal particle with an air–water interface. J. Phys. Condens. Matter 14, 4881–4900 (2002).

    Article  CAS  Google Scholar 

  20. Brenner, H. The slow motion of a sphere through a viscous fluid towards a plane surface. Chem. Eng. Sci. 16, 242–251 (1961).

    Article  CAS  Google Scholar 

  21. Paunov, V. N. Novel method for determining the three-phase contact angle of colloid particles adsorbed at air–water and oil–water interfaces. Langmuir 19, 7970–7976 (2003).

    Article  CAS  Google Scholar 

  22. Hodge, I. M. Physical aging in polymer glasses. Science 267, 1945–1947 (1995).

    Article  CAS  Google Scholar 

  23. De Gennes, P., Brochard-Wyart, F. & Quere, D. Capillarity and Wetting Phenomena: Drops, Bubbles, Pearls, Waves (Springer, 2003).

    Google Scholar 

  24. Blake, T. D. & Haynes, J. M. Kinetics of liquid/liquid displacement. J. Colloid Interface Sci. 30, 421–423 (1969).

    Article  CAS  Google Scholar 

  25. Rolley, E. & Guthmann, C. Dynamics and hysteresis of the contact line between liquid hydrogen and cesium substrates. Phys. Rev. Lett. 98, 166105 (2007).

    Article  CAS  Google Scholar 

  26. Prevost, A., Rolley, E. & Guthmann, C. Thermally activated motion of the contact line of a liquid 4He meniscus on a cesium substrate. Phys. Rev. Lett. 83, 348–351 (1999).

    Article  CAS  Google Scholar 

  27. Petrov, J. G., Ralston, J., Schneemilch, M. & Hayes, R. A. Dynamics of partial wetting and dewetting of an amorphous fluoropolymer by pure liquids. Langmuir 19, 2795–2801 (2003).

    Article  CAS  Google Scholar 

  28. Blake, T. D. The physics of moving wetting lines. J. Colloid Interface Sci. 299, 1–13 (2006).

    Article  CAS  Google Scholar 

  29. Brochard-Wyart, F. & de Gennes, P. G. Dynamics of partial wetting. Adv. Colloid Interface Sci. 39, 1–11 (1992).

    Article  CAS  Google Scholar 

  30. Oettel, M. & Dietrich, S. Colloidal interactions at fluid interfaces. Langmuir 24, 1425–1441 (2008).

    Article  CAS  Google Scholar 

  31. Park, B. J., Vermant, J. & Furst, E. M. Heterogeneity of the electrostatic repulsion between colloids at the oil–water interface. Soft Matter 6, 5327–5333 (2010).

    Article  CAS  Google Scholar 

  32. Park, B. J. & Furst, E. M. Attractive interactions between colloids at the oil–water interface. Soft Matter 7, 7676–7682 (2011).

    Article  CAS  Google Scholar 

  33. Stamou, D., Duschl, C. & Johannsmann, D. Long-range attraction between colloidal spheres at the air–water interface: The consequence of an irregular meniscus. Phys. Rev. E 62, 5263–5272 (2000).

    Article  CAS  Google Scholar 

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Acknowledgements

We thank S. Ghosh for his help in the work that inspired these experiments; L. DeLorenzo for her work on sample cell prototypes; S. Rubinstein and H. Stone for critical discussions; and J. MacArthur and S. Cotreau for guidance in construction of the apparatus. This work was supported by the National Science Foundation under CAREER award number CBET-0747625 as well as through the Harvard MRSEC under award number DMR-0820484.

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Author notes

  1. Madhav Mani

    Present address: Present address: Kavli Institute for Theoretical Physics, Department of Physics, University of California, Santa Barbara, California 93106, USA,

  2. David M. Kaz and Ryan McGorty: These authors contributed equally to this work

Authors and Affiliations

  1. Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA

    David M. Kaz, Ryan McGorty & Vinothan N. Manoharan

  2. School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA

    Madhav Mani, Michael P. Brenner & Vinothan N. Manoharan

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  1. David M. Kaz
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  3. Madhav Mani
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  5. Vinothan N. Manoharan
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Contributions

R.M. and D.M.K. designed the experimental apparatus, analysed the data and interpreted the results. M.M. led the development of the model and assisted with interpretation of the data. M.P.B. advised on the model and manuscript. V.N.M. directed the experiments and their interpretation. All authors collaborated on the manuscript.

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Correspondence to Madhav Mani or Vinothan N. Manoharan.

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The authors declare no competing financial interests.

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Kaz, D., McGorty, R., Mani, M. et al. Physical ageing of the contact line on colloidal particles at liquid interfaces. Nature Mater 11, 138–142 (2012). https://doi.org/10.1038/nmat3190

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