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The novel oxidant of sodium hypochlorite pentahydrate (NaOCl·5H2O) crystals is now available for industrial and laboratory use. It is superior to conventional aqueous sodium hypochlorite solutions (aq. NaOCl). The crystalline material is 44% NaOCl and contains minimal amounts of sodium hydroxide and sodium chloride, and the aqueous solution, which is prepared from NaOCl·5H2O and water, has a pH of 11–12. Examples of the selective organic synthesis using NaOCl·5H2O involve the oxidations of primary and secondary alcohols, selective oxidations to sulfoxide and sulfone, oxidative cleavage of disulfide to sulfonyl chloride and bromide, oxaziridine synthesis, and oxidative dearomatization of phenols.

The thermal behavior was investigated for the Zn complexes of carbohydrazide and semicarbazide with Sr(NO3)2 and 10% CuO as the oxidizing agent. In both complexes, there was little difference in the various combustion characteristics. The combustion reactivity was relatively low compared with the case of using other oxidizing agents, such as KBrO3, etc. But the participation of CuO in the reaction was supposed to be different based on the analysis of the combustion residue. As for the gas evolution behavior, the evolution of N2, NH3, N2O, NOx and COx gases was confirmed upon ignition at 500°C in both complexes (no H2O analysis). It was interesting that CO gas not evolved from the semicarbazide complex. It was clear that the combustion reactivity and the gas evolution behavior vary in both complexes in spite of the same skeleton and similar oxygen balance.

No abstract

A novel procedure for the preparation of nanosized nitrocellulose (NC) was developed. Cellulose nanofiber (CNF) water suspension was obtained by disk-milling of cotton powder. CNF was first pretreated using sulfonic acid to enhance the esterification process using HNO 3 and H 2 SO 4 . The esterification process generated nitrocellulose nanofiber (NCNF) with a nitrogen content of 9.0 %-13.7 %. The Brunauer-Emmett-Teller (BET) specific surface area of NCNF was ten times larger than that of NC, and the burn-ing rate of NCNF was 3.5 times faster than that of NC. Differential scanning calorimetry (DSC) was conducted to assess the difference between the thermal stability of NCNF and NC. NCNF and NC exhibited the same onset exothermic temperature (200°C), the height of the exothermic peak of NCNF was 20 % higher than that of NC. Thus, NCNF has great potential to be used in explosives due to its high combustion performance.