Cellulose nitrate or nitrite prepn. - by reacting cellulose with dinitrogen tetroxide or nitrosyl chloride

摘要

Prepn. comprises reacting cellulose contg. 4-12 wt.% of uniformly dispersed H2O with N2O4 or NOCl in the presence of a proton acceptor and a solvent which swells or solubilises the cellulose nitrite product. The reaction temp. is 50 degrees C (pref. 30 degrees C), and the solvent is used in an amt. of =3 pts. wt. per pt. wt. of cellulose. The resulting cellulose nitrite is opt. further reacted with HNO3 at ca. 110 degrees C to form the nitrate. The products can be converted into alkali metal cellulose sulphates with a low but uniform degree of substitution (DS). Sulphates with DS = 0.3-1.0 form viscous aq. solns. and can be used as dispersant additives for drilling fluids, thickeners for waterflood drive fluids, cosmetic emolli thickeners and stabilisers for food products and cleaning compsns.; and additives for adhesives, wax emulsions, paints and photographic emulsions. Sulphates with DS 0.3 are insoluble but swellable and can be used as absorbents. The nitrites can also be converted into films and fibres.