Development of a thermal aging model for sound-absorbing polyurethane foam

Abstract

This research aims to establish a reliable thermal aging model of sound-absorbing polyurethane foam (PUF). To achieve this objective, accelerated testing was conducted in a heat chamber under various conditions. The transport parameters (open porosity, high-frequency limit of the dynamic tortuosity, viscous characteristic length, thermal characteristic length, and static thermal permeability) of original and aged PUF were characterized and investigated. Curve fitting was performed to predict the value of each transport parameters corresponding to the level of thermal aging from the collected data. The thermal aging model of PUF was constructed using the Layton model and Arrhenius equations, which showed good agreement with the measured data. By employing the proposed thermal aging model, it became possible to forecast the acoustic behavior of PUF at different aging temperatures and aging periods. Subsequent testing of PUF sample materials confirmed the validity and efficiency of the developed aging model. These findings provide a crucial reference for creating a predictive model for the acoustic behavior of PUFs undergoing thermal aging and offer valuable insights for designing an accelerated testing approach.