The Effects of Various Additive Components on the Sound Absorption Performances of Polyurethane Foams

Figure 12

Curves of absorption coefficients of the PU foams with added triethanolamine. (a) Group 1 with 3.8 parts by weight, (b) Group 2 with 4.1 parts by weight, (c) Group 3 with 4.4 parts by weight, and (d) Group 4 with 4.7 parts by weight.