Influence of Dynamic Rheological Behavior on Final Coating Properties Part 1: Relationships Between Suspension Rheology at Equilibrium State and Dry Coating..., 1999 Coating Conference Proceedings

Hideaki Nisogi, Douglas W. Bousfield & Pierre LePoutre

Department of Chemical Engineering

University of Maine

The effects of the addition of an associative thickener on the viscoelastic properties of the wet coating and on the dry coating bulk are reported. As the concentration of a hydrophobic thickener increases, the wet coating elasticity increases and the final dry coating void fraction increases. A logarithmic equation describes the relationship between the elastic modulus and the void fraction and the light scattering coefficient. The relationship may be a result of the increased network strength caused by the polymer. This increased strength increases the elastic modulus in the wet state and helps the coating components withstand stresses during coating consolidation. This strengthening results in a direct relationship between the viscoelasticity of the wet coating suspension and the dry coating bulk. This relationship depends on the coating solids: increasing solids increases the elasticity of the coating but decreases the coating bulk. This is first attempt to quantify this relationship between the suspension elasticity and the dry coating bulk.