Fractionation of cellulose trinitrates by gel permeation chromatography

Abstract

AbstractSamples of the four polymorphic forms of cellulose (I, II, III, and IV) have been nitrated and examined by means of gel permeation chromatography (GPC). Shifts in the differential and integral distribution curves indicate that the processes for lattice conversion affect the molecular weight distribution of the cellulose molecules in the samples. Weight‐average and number‐average degrees of polymerization for the four samples exhibit trends parallel to those observed in the average degrees of polymerization of the initial celluloses measured viscometrically where the celluloses were dissolved in cupriethylene diamine and in cadmium ethylene diamine hydroxide solutions. The weight‐ and number‐average values, however, are markedly greater than the viscosity values. The order of magnitude of the GPC data, however, was similar to average degrees of polymerization of cellulose reported in the literature which were obtained by other methods.