Table 3.

Foaming behavior of the PU resins.

Code	Cream time (s)	End of rise time (s)	Tack-free time (s)	Volume expansion (%)
P-2-2	32	62	90	250
P-2-3	33	62	81	360
P-2-4	31	62	83	500
P-3-2	26	46	58	300
P-3-3	26	48	60	340
P-3-4	29	56	80	380
P-4-2	22	47	54	300
P-4-3	28	47	60	330
P-4-4	23	41	59	350