Cellulose acetates with various acetyl values (D. S. 0_??_3.0) were oxidized with NO
2 gas, and the amounts of their functional groups were determined by infrared spectrometry. The results are as follows:
1) The determination on the film samples gave more sensitive and accurate results than on the KBr disc samples.
2) The treatment of cellulose acetate with purified NO
2 which did not deacetylate the samples, produced carboxyl and nitrate groups in place of hydroxyl groups. The nitration took place rapidly up to 2.7 N % with no futher increase even though hydroxyl groups remained in the samples.
3) Even when a very small amount of H
2O was mixed with NO
2, the extent of oxidation decreased very much, and the nitration took place considerably.
4) The behavior of the cellulose acetate, which had been saponified below D. S. 1.5 in the reaction with NO
2 was almost similar to that of amorphous regenerated cellulose with NO
2.
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