(357c) Rheology of Particle-Laden Polymeric Fluids: A Perspective from Mixing Orders

Polymeric materials serve as key components in almost every can of paints. It is known that the preparation of paints is a complex process, and many factors contribute to the final coating properties. In this study, the order of addition of several key components in an automotive clear coat was varied to understand and demonstrate the impact of the formulation process. It was found that the rheological properties of these multi-component polymeric fluids depend not only on the mixture compositions, but also on the order of addition. For the system studied here specifically, it was found that the relative order between certain polymer and particulate additives plays a vital role in determining the rheological properties of the mixture. Further, NMR tests suggest a competitive interaction between each component, and shed light on the microscopic origin of the observed differences. These findings provide significant practical guidance to the manufacturing.