ISO 11443 – Rheology of low viscosity fluid for spray application

Rheology analyzes the flow properties of fluids and is key to understand their behavior under industrial processing conditions. Low viscosity fluids are usually tested with rotational rheometers, but this is not enough when high-shear processing conditions need to be simulated. So depending on the application, this kind of fluids (such as paints, glues, adhesives, etc…) should preferably be tested by means of a capillary rheometer.

We were asked to test glue and paint samples consisting of water based polymer dispersion, in order to investigate suitability of a spraying process (very high shear). We used a capillary rheometer, managed through the dedicated software.

Rheological tests (ISO 11443) were performed at room temperature by applying constant shear rate steps in a range from 3’000 to 2’000’000 1/s, and measuring pressure at equilibrium. Tests were repeated three times on each sample in order to evaluate the repeatability of results.