Solid Coating Development

Solid Coating Development

After successful deposition of a coating liquid, coatings are solidified by drying, curing, cooling, or coalescence. During solidification, microstructure and properties develop.

Solidification must be understood at a fundamental level in order to maximize the overall yield of a coating process, and to develop the desired microstructure and properties of the final coating. Diffusion and mass transport (drying), chemical reaction kinetics (curing), heat transfer (cooling), particle-particle interactions (coalescence) and often combinations of these are at the heart of solidification research. Coupled with solidification is the development of stress, which along with adhesion and coating mechanical properties, determines the durability and likelihood of defects, such as delamination. Additionally, the microstructure and nanostructure of the coating is born during solidification, and it is the microstructure that eventually impacts the properties and performance of the coating. The connections between the solidification process, the development of stress and microstructure, and the coating properties create a complex, but interesting and important platform for research projects.

Our research approach combines experimental methods that are particularly geared to characterizing solid coating development as it happens: a computer controlled system monitors weight loss during drying, cryo-SEM captures microstructure of dispersions and coatings as they dry, cantilever beam measurement monitors accumulation of stress, FTIR and Raman spectroscopies follow composition and structure change, and so on. Whenever possible, theory-based models complement the experiments.

Read more about Coating Flows.

Current research topics

  • Drying — kinetics, microstructure effects
  • Curing — E-beam, UV, network modeling
  • Colloidal self assembly
  • Latex coalescence and microstructure
  • Nanoparticle coatings
  • Cryo-SEM of coatings
  • Microstructure of particulate coatings
  • Stress development
  • Mechanical properties

Coating Images

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Cryo-SEM of aqueous dispersion of nanoparticles and latex
From H. Luo, L. E. Scriven, L. F. Francis, J. Colloid Interface Sci. 316 (2007) 500-509.

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SEM of nanotiled zeolite coating prepared by convective self assembly 
From J. A. Lee, L. Meng, D. J. Norris, L. E. Scriven, Langmuir. 22 (2006) 5217 - 5219.

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Prediction of gelation through the thickness of a coating that forms wrinkles on curing
From S. Basu, J. A. Chung, L. F. Francis, A. V. McCormick and L. E. Scriven Ind. Eng. Chem. Res., 46(2007), 3358 -3365.