Mercerization ofAgave americanaL. fibers

This study investigates the change in crystalline structure of Agave americana L. fibers during alkali process at different NaOH concentrations. X-ray diffraction spectroscopy was used to determine the crystallinity, the crystal size, and the unit cell dimensions of the treated Agave samples. The X-ray diffractograms of both untreated (0% NaOH) and alkali-treated samples show a pattern quite similar to the four peaks characteristic of native cellulose (cellulose I). The intensity of the (0 0 2) crystallographic plane increased significantly by alkali treatment of Agave fiber. When treated with 2% wt/v NaOH, the polymorphic transformation of cellulose I to cellulose II occurs as indicated by the appearance of the diffraction at 2θ = 20.5° resulting from the lattice plane of cellulose II. The unit cell parameters of Agave americana L. fibers vary with NaOH concentration which results from the formation of different alkali celluloses during the mercerization process. As far as mechanical properties are concerned, treatments with low alkali concentrations produce fibers that are stronger than the untreated fibers, whereas treatments with high concentrations (>2% wt/v) result in weaker fibers.