| The purpose of this study was to obtain measurements of elasticity under extensional flow for paper coating fluids and to relate the measurements to misting tendency in the film coating process. To obtain measurements, a filament-stretching rheometer imposed a constant extensional rate on fluids and the elasticity was found using a new technique, which is based on the Hencky strain at filament failure. Coating formulations, dilute polymer solutions, and common fluids were tested using this new technique, and their elasticities were found to increase with extensional rate. A comparison of the measurements for the coating fluids showed that the formulation that was most elastic also had the highest misting tendency in the coating press. |
