Studies on the use of nano zinc oxide and modified silica in NR, CR ...

Chapter 3
3.4.7. Fourier transform infrared spectroscopy
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Figure.3.4 FTIR spectrum of ZnO sample prepared by (a) method 1 (b) method 2
(c) Conventional ZnO
Figure 3.4 shows the IR spectra of ZnO samples. The peak at 450 cm -1
shows the distinct stretching vibration of zinc oxide.
3.4.8. Thermogravimetric analysis
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Figure 3.5 Thermogravimetric analysis of zinc oxides (a) ZnO(p) (b) ZnO(s)
From the figure it is seen that TGA curve for the nano ZnO from
pyrolytic method shows the absence of any actual loss in weight. This
indicates the thermal stability and high purity of nano ZnO(s). The TGA
curve for the nano ZnO from precipitation method shows a very small
decrease in weight percentage at around 190°C-250°C. As reported by
Morishige et al. 26 the peaks at around 250°C may be caused by the
decomposition of the condensation dehydration of the hydroxyls.