Table 6. Assignments for Selected Key Bands Apparent in the PCA of the Raman Vibrational Spectra.

peak range (cm–1)	proposed assignment	reference source
1615–1620	C–C stretch in benzene ring	(31, 32)
1584–1590	C–C stretch in benzene ring	(31)
1575	C–C stretch in benzene ring	(31)
1486–1489	C–H bend in CH2	(27, 33)
1451–1455	CH2 scissoring (ring)	(26, 27)
1434	CH2 scissoring (ring)	(26, 27)
1308–1325	CH2 wag	(27, 33)
1285–1288	C–H bridge	(31, 33)
1205–1215	C–O–C or possibly C–N–C asymmetric stretch (ring closed)	(27)
1192	C–N–C asymmetric stretch (ring closed)	(27)
1172–1174	C–H bending (ring)	(33)
1118	Wilson 18b (ring closed)	(27)
1104	C–N–C symmetric stretch (ring closed)	(27)
1049–1052	C–O–C symmetric stretch of ring or during cure	(33) (ring), (27) (curing)
1033	C–C stretching vibration of ring	(33)
999	C–C bending vibration of ring	(27)
860	C–N–C symmetric stretch (ring closed)	(27)
745–751	benzoxazine ring breathing	(27)