Monitoring the continuous manufacture of a polymeric foam via a thermokinetic-informed acoustic technique

Polymer foams are difficult to characterise due rapidly evolving physical features from liquid porous solid. Swift changes in volume, porosity and moduli render many techniques challenging for the characterisation of foam curing during a manufacturing process. A technique that employs longitudinal speed sound an ultrasonic signal, informed by thermokinetic model, is proposed as situ, in-line, non-destructive continuous monitoring tool production rigid polyurethane foams. This study demonstrates measurements suitable (a) different foaming stages polymer reaction curing; (b) determining degree cure foams, (c) predicting mechanical properties (i.e., stiffness Poisson's ratio) cured samples. The validity this confirmed comparison with well-established methods use characteristics (e.g., expansion rate, electrical properties), thermo-kinetic models testing. method positions itself convenient material production.