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

Table 2

Foam formulation and design.

Main component	Group 1	Group 2	Group 3	Group 4
	(parts by weight)	(parts by weight)	(parts by weight)	(parts by weight)
3630	28	28	28	28
330N	52	52	52	52
MDI	28.8	28.8	28.8	28.8
Catalyst A1	0.04	0.04	0.04	0.04
Catalyst A33	0.9	0.9	0.9	0.9
Silicone	0.9	0.9	0.9	0.9