Enhanced Strain-Dependent Electrical Resistance of Polyurethane Composites with Embedded Oxidized Multiwalled Carbon Nanotube Networks

Table 2

Some peaks in FTIR spectra of TPU and TPU/MWCNT-Ns composites.

Possible assignments	Wavenumber (cm^−1)
	TPU	TPU/MWCNT-N	TPU/MWCNT-N; (H2O2)	TPU/MWCNT-N; (HNO3)	TPU/MWCNT-N; (KMnO4)
C=O stretch	—	1759, 1744	1748	1759, 1743	1759
Free C=O stretch	1728	1726	1715	1723	1725
C=O stretch for hydrogen; bonded urethane group	1706	1710, 1690	1700, 1683	1708, 1689	1707, 1688
C=O stretch for hydrogen; bonded ester group	1662	1665	1652	1664	1662
NH bending + C=C stretch	1597	1574	1573	1574	1577
C–N stretch + N–H bending	1531	1535	1538	1539	1539