Sodium stearate, infrared

Infrared evidence for the formation of an acid-soap complex is, of course, most cogent for the species existing in phase 2, where the main absorption band of the C=0 group centers at a frequency different from that of either of the two constituents. Similar absorption at 6.1 microns for the 1 to 1 sodium stearate-stearic acid complex had been observed by one of us (S. G.). Some of the acid-soaps show a complete absence of the 6.4-micron absorption band (Table II). It is therefore likely that this band in the spectra of the other acid-soaps results from the presence of a small amount of unreacted soap which has very strong absorption at this frequency. On the other hand, acid-soaps in the 1 (or 3) phase are seldom completely free of 6.1-micron absorbing material—i.e., phase... 

Figure 3.18 shows infrared spectroscopic information of aluminum borate whiskers before and after being modified with sodium stearate. As shown in Figure 3.18, when aluminum borate whiskers are modified, the infrared adsorption peaks at 2918 cm" (asymmetrical stretching vibration of C-H bond in CHj) and 2851 cm" (symmetrical stretching vibration... 

To characterize further the mode of action of sodium stearate molecules and the surface of the whiskers, we apply the same approach to the aluminum borate whiskers. Infrared spectra of aluminum borate whiskers before and after modification are shown in Figure 5.11. 

Figure 5.12 Infrared spectra of calcium carbonate whiskers before and after modification, (a) Calcium carbonate whiskers before modification. (b) Calcium carbonate whiskers after modification, (c) Sodium stearate.

Rg. 5.8. CH2 wag band progression seen in the solid state infrared spectrum of sodium stearate. 

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