Mean interaction parameter between polymer and other components of coating colors

In a previous paper, we showed that the three dimensional network structure of a coating color system is significantly controlled by the polymer components. Here we analyse the data using a simple model. We introduce the mean interaction parameters between the components of the coating color such as starch and styrene-butadiene latex (SBL). Comparing the shear rate dependence of the viscosity of the coating color with that of the aqueous starch solution and/or aqueous SBL dispersion, we determine the interaction parameter assuming that the viscosity of each system increases exponentially with increasing weight fraction of starch and/or SBL. From this analysis we discuss the structure change of the coating color by shear and found at high shear rate, the clay-clay interaction increases due to the parallel orientation of the clay particles. We also found that the critical starch concentration needed to form the three dimensional network structure corresponds to that of the inflection point of starch concentration dependence of the coating color viscosity.