Cellulose materials, denitration

An ESCA Investigation Of The Surface Chemistry Of The Nitration And Denitration Of Cellulose Materials... 

It is clear therefore that ESCA provides a new dimension to this complex problem of the nitration-denitration of cellulose materials and the work described here provides a strong basis for the study of the even more complex systems represented by double and triple based propellant formulations. 

Several processes have evolved for the preparation of regenerated cellulose. One, developed as far back as 1884, converts it first to a nitrate ester. The nitrated material is dissolved in a mixture of ethyl alcohol and diethyl ether and extruded into fibers. The fibers are then denitrated by treatment with ammonium hydrogen sulfide at about 40 °C. The product is called Chardonnet silk. It appears that this process is no longer practiced anywhere. 

At about the same time as Edison was undertaking his work in the USA, Sir Joseph Swan in England had invented an electric lamp and in 1883, produced a precursor material for his carbon fiber lamp filaments by extruding a solution of nitrocellulose dissolved in acetic acid through a small hole into a bath of ethanol and collecting the drawn coagulated fiber, which he later denitrated with a solution of ammonium sulfide, to regenerate the initial cellulose. 

The first form of regenerated cellulose was developed in 1884 by de Chardonnet. Cellulose was nitrated and dissolved in a mixture of ether and ethanol. The solution was extruded through a small orifice and the solvent evaporated to leave a fibre. The fibre (which was too inflammable for direct use) was then passed through aqueous ammonium hydrogen sulphide at about 40°C this treatment resulted in denitration. The product (often called Chardonnet s/ifc) was popular for many years but was gradually displaced by other synthetic fibres. Commercial production of the material ceased in 1949. 

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