Institute of Physical Chemistry > Research > Film formation from latex dispersions

Film formation from latex dispersions

Is it boring to watch paint dry?  That depends on the paint.  There is a lot of modern technology inside a bucket of paint.

Today, most paints are water-based.  The starting material is a dispersion, that is, a liquid matrix containing many small solid particles.  The particles are so small (~ 0.1 µm) that they do not sediment.  Applying the paint to the substrate initiates the film formation process.  In a first stage, water evaporates, until the particles touch.  The fact that the evaporating liquid is water (as opposed to environmentally more harmful organic solvents) is a central benefit of latex dispersions.  In stage II of the film formation process, the particles deform, until the voids between particles have completely closed.  Finally, different particles fuse together, which involves the rupture of the surfactant membranes in-between different particles and interdiffusion of polymer chains across the interparticle boundaries.  One may increase the film's mechanical strength by chemical crosslinking after film formation.

A major challenge in the film formation process is the creation of a hard coating from a soft starting material (the "film formation dilemma").  Initially, the polymer particles need to be soft enough to undergo deformation.  A related problem is cracking.  In this case, the particles deform and even fuse to some extent, but the cohesion is not good enough to withstand the drying- induce tensile stress.

Selected Publications

     

  • Nikiforow, I.; Adams, J.; Konig, A. M.; Langhoff, A.; Pohl, K.; Turshatov, A.; Johannsmann, D.,

    Self-stratification during film formation from latex blends driven by differences in collective diffusivity.

    Langmuir 2010, 26, (16), 13162-7.

  • Koenig, A. M.; Weerakkody, T. G.; Keddie, J. L.; Johannsmann, D.,

    Heterogeneous drying of colloidal polymer films: Dependence on added salt.

    Langmuir 2008, 24, (14), 7580-7589.

  • Turshatov, A.; Adams, J.; Johannsmann, D.,

    Interparticle contact in drying polymer dispersions probed by time resolved fluorescence.

    Macromolecules 2008, 41, (14), 5365-5372.

  •  

     

 

Contact  Search  Sitemap  Datenschutz  Imprint
© TU Clausthal 2017