Materials produced from plant biomass: part II: evaluation of crystallinity and degradation kinetics of cellulose

Abstract

In this study Eucalyptus grandis (CEG) and Pinus taeda (CPT) cellulose fibers obtained from kraft and sulfite pulping process, respectively, were characterized using Fourier transform infrared (FTIR) spectroscopy and thermogravimetry (TGA). The degradation kinetic parameters were determined by TGA using Coats and Redfern method. FTIR results showed that CPT presented a more ordered structure with higher crystallinity than CEG. Thermogravimetric results showed that CPT had a higher thermal stability than CEG. The kinetic results revel that for CEG the degradation mechanism occurs mainly by random nucleation, although phase boundary controlled reactions also occurs while for CPT the degradation process is more related with phase boundary controlled reactions. Results demonstrated that differences between thermal stability and degradation mechanisms might be associated with differences in the cellulose crystalline structure probably caused by different pulping processes used for obtaining the cellulose fibers.

Analysis of the physical properties of developing cotton fibres

“…indicates that fibres contain more cellulose chains in a well ordered form leading to a higher HBI between neighbouring cellulose chains, resulting in higher crystallinity [60]. This is also in agreement with obtained results for birefringence (Figure 7a), where the most significant changes in crystallinity occur due to the drawing of the fibre.…”

Fabrication of bacterial cellulose thin films self-assembled from sonochemically prepared nanofibrils and its characterization

“…TCI is proportional to the crystallinity degree of cellulose, while LOI is related to the overall degree of order in cellulose [36]. Poletto et al report that cellulose samples with higher TCI, LOI and HBI might demonstrate higher crystallinity.…”

Materials produced from plant biomass: part III: degradation kinetics and hydrogen bonding in lignin

“…Several techniques have been used to characterize the structural aspects and functional groups present in lignin [1][2][3][4][5] . Therefore, infrared spectroscopy has been proven to be a highly effective means of investigating specific interactions within and between molecules [6][7][8] . FTIR can be used to qualitatively and quantitatively study the mechanism of intermolecular interactions through hydrogen bonding [7][8] .…”