M C. Paina et al. / Carbon 41(2003)1399-1409 1403 Activation energies and rate constants determined by the Kissinger method [8] Precursor Activation energy erage reaction verage frequency (KJ/mol) factor(s) VT 112 7×10 0)FIbers L OOE-O1 8.00E02 E02 UV 2400E02 irradiated 2.00E02 一Mm 0.00E+00 360031002600210016001100600 mber(cm-1 b)VT Fibers 4.00E02 3.00E02 10OE02 -As spu 0.00E+00 38003400300026002200180014001000600 Fig. 5. ATR-FT-IR spectra of (a) M fibers and (b)VT fibersM.C. Paiva et al. / Carbon 41 (2003) 1399–1409 1403 T able 2 Activation energies and rate constants determined by the Kissinger method [8] Precursor f Tm Activation energy Average reaction Average frequency 21 (K/min) (K) (KJ/mol) order factor (s ) 12 M 5 553.6 157 1.0 3310 10 564.1 20 575.7 7 VT 5 571.5 112 1.0 7310 10 586 20 604 Fig. 5. ATR-FT-IR spectra of (a) M fibers and (b) VT fibers