No abstract

By thermally treating a commercial cellulose in ethylene glycol, celluloses of controlled low degree of polymerization, DPr = 1000 to 70, can be derived. Two general behaviors are observed in the range studied. At first, the depolymerization reaction is predominant down to a DP equal to 130. Beyond this level, the depolymerization process leads to extensive solubilization of the cellulose. The treated celluloses have been analyzed by X‐ray diffraction, FTIR, TGA, elemental analysis and enzymatic hydrolysis. No chemical change of the cellulose could explain the two different behaviors. A physical modification in the form of depolymerization and destructuration is suspected.

The composition of the ethylene glycol solution resulting from cellulose thermal solvolysis, to produce microcrystal‐line cellulose, has been studied. Liquid and gas chromatographic analyses showed, a) little degradation of the ethylene glycol up to 280°C, and b) an acceleration of the degradation at higher temperatures in the presence of cellulose and glucose. Solubilized compounds resulting from the cellulose depolymerization although numerous were present in too low concentrations to warrant their recovery.