45 research outputs found
In situ label-free imaging of hemicellulose in plant cell walls using stimulated Raman scattering microscopy
New methods for cellulose characterization using FT raman spectroscopy and multivariate calibration methods
New method for determining the degree of cellulose I crystallinity by means of FT Raman spectroscopy
A Raman crystallinity index - Xc(Raman) - characterizing the degree of crystallinity of partially crystalline cellulose I samples was created, utilizing the crystallinity dependence of CH2 bending modes. For calibration, physical mixtures containing different mass fractions of crystalline cellulose I and its amorphous form were prepared. Crystallinities from 0 to 60% were generated. Relative intensity ratios of the Raman lines I-1481 (cm-1) and I-1462 (cm-1) characterizing crystalline and amorphous parts of cellulose I correlated linearly with the mass fraction of crystalline cellulose I of the mixtures. Xc(Raman) values of microcrystalline celluloses of different origins and varying degree of crystallinity correlated reasonably with results obtained from NMR spectroscopy (Xc(NMR) values)