Cellulose, explosives Normal

Table XI, page 144, gives indications of temperatures of processing for a number of materials. With cellulose nitrate plastics in particular there was a risk of explosion if over-heating took place, so besides all normal safety precautions for press-work the operating temperature of presses was subject to strict control.

Observe normal precautions appropriate to the circumstances and quantity of material handled. Hydroxyethyl cellulose dust may be irritant to the eyes and eye protection is recommended. Excessive dust generation should be avoided to minimize the risks of explosion. Hydroxyethyl cellulose is combustible. 

Table 1 summarizes some representative solvents or solvent systems for cellulose. The xanthate system has been used for a longtime to make viscose rayon and sponge. However, rayon production, where H2S is released to varying amounts during the recovery system of spent solvent, is shrinking because of environmental issues. On the other hand, cellulose is soluble in aqueous NaOH alone under limited conditions. Microcrystalline cellulose with DP 200—300 is soluble in 6—9% NaOH by freezing and defrosting procedures. Pretreatments of cellulose such as steam explosion are necessary for complete dissolution in the aqueous NaOH for normal bleached wood pulp and cotton linters with DP of more than 500. ... 

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