A new value for the heat of fusion of a perfect crystal of cellulose acetate

The enthalpy of fusion of a perfect crystal (Delta H-f degrees) of cellulose acetate was determined in this work. In order to do so, cellulose samples from different sources were heterogeneously acetylated. The cellulose acetate samples were characterized by differential scanning calorimetry (DSC) and wide angle X-ray scattering (WAXS). The diffractograms were deconvoluted into halos and peaks using the Pseudo-Voigt peak function. From these deconvolutions, the hypothesis that best represented the two-phase model was the one in which the amorphous model was represented by the halos at 11 degrees and 21 degrees, considering an ordered amorphous model. The WAXS crystallinities of the samples were then calculated from these values and plotted against the enthalpy of fusion of the materials, and from this relationship the Delta H-f degrees for the cellulose acetate was determined to be 58.8 J/g.