Thermal Investigation of Diethylaminoethyl-Substituted Cotton Celluloses

Abstract

The thermal behavior of diethylaminoethyl-substituted cotton celluloses was examined by thermogravimetric analysis, differential thermal analysis, and differential scanning calorimetry. Samples at levels up to 10% substituent content (prepared via an anhydrous sodium cellulosate method) were compared with other samples prepared by the conventional aqueous sodium hydroxide method. All thermal analyses were carried out in purified dry nitrogen or high vacuum at heating rates of 5-40°C/min. Considerable variation was observed when the samples in the base form were compared with those placed in the salt (hydrochloride) form. The effect of basic diethylaminoethyl groups on the cellulosic thermal degradation was shown in altered thermal patterns and Δ H of pyrolysis. In the hydrochloride form, lower Δ H of pyrolysis and decreased decomposition temperature were observed. These observations together with other minor thermal effects which were found to be associated with the decomposition, are compared with recent studies on the effect of inorganic bases on the pyrolysis of cotton cellulose.