(517e) Propellant Dough Screening using Squeeze Flow Characterization

The benefit of the squeeze flow durometer is to remove variability in propellant processing by providing a quantitative means of assessing when a propellant mix is at the proper consistency for further processing (e.g. extrusion, cutting, etc). Currently the mixer operator determines when a propellant mix is ready by handling the material and making a qualitative decision as to whether the propellant is properly mixed and contains the correct level of residual solvent. While a properly trained operator may be able to consistently determine when a mix is ready for further processing, results vary between operators, introducing batch to batch propellant variation. The durometer decreases operator variability through more accurate and reproducible means of measurement. This presentation covers the method of data collection and interpretation for the squeeze flow durometer, as well as results showing how consistent solvent level aids in further propellant processing.