The sound absorption coefficient of polyurethane foams is high (0.8 1.0) in high frequencies in the range 300 to 10000Hz while it is found to be low (0 to 0.5) at low frequencies (10 to 200 Hz). The sound absorption coefficient of filled PU foams increases from 0.5 to 0.8 with frequency increase from 100 to 200 Hz at higher content of the nanofillers employed.
The sound absorption coefficient of polyurethane foams is high (0.8 1.0) in high frequencies in the range 300 to 10000Hz while it is found to be low (0 to 0.5) at low frequencies (10 to 200 Hz). The sound absorption coefficient of filled PU foams increases from 0.5 to 0.8 with frequency increase from 100 to 200 Hz at higher content of the nanofillers employed.<br>