Table 1.

Index of vibration modes of the FTIR spectra of polyurea, pure magnetite, and 3% magnetite-modified composite.

Characteristic Band Number	Band Assignments
1	N–H stretch amides
2	C–H stretching bond in CH2 and CH3 groups
3
4	N=C=O (isocyanate) stretching
5	C=O & C=C conjugated stretching
6	NO2 aliphatic nitro group
7	N–H bending
8	Nitro compounds NO2 asymmetric
9	C–O–C asymmetrical stretching
10	N–H bending and C–N stretching
11	Carbonates
12
13	Alkene sp2 CH bending
14	Fe-O stretching splitted bands
15