Supplement Information
Probing crystallinity of never-dried wood cellulose with Raman spectroscopy
Umesh P. Agarwala,*, Sally A. Ralpha, Richard S. Reinera, Carlos Baeza
aFiber and Chemical Sciences Research, USDA FS, Forest Products Laboratory, 1 Gifford Pinchot Drive Madison, WI 53726-2398.
*To whom correspondence should be addressed. Email:
Fiber and Chemical Sciences Research, USDA FS, Forest Products Laboratory, 1 Gifford Pinchot Drive Madison, WI 53726-2398
Ph: 608-231-9441
Table SI1: % O6s that are D2O accessible under various models of crystalline celluloseCrystal model* / Surface chains / Interior chains / N = Ratio of surface-to-total chains / N/2 = D2O accessible O6s / % O6s D2O accessible
36 chain, square cross section / 20 / 16 / 0.56 / 0.28 / 28
30 chain, rectangular cross section (6 x 5) / 18 / 12 / 0.60 / 0.30 / 30
24 chain rectangular cross section (6 x 4) / 16 / 8 / 0.67 / 0.33 / 33
18 chain rectangular
cross section (6 x 3) / 14 / 4 / 0.78 / 0.39 / 39
*A microfibril arises from a rosette of six particles on the plasma membrane. Therefore, it is
reasonable to assume that a microfibril comprises of a multiple of six cellulose chains.
Fig. SI1(a): Raman spectra of SA2-ND in D2O and H2O, 850 – 1550 cm-1 region.
Fig. SI1(b): Raman spectra of SA7-ND in D2O and H2O, 850 – 1550 cm-1 region.
Fig. SI1(c): Raman spectra of SA18 in D2O and H2O, 850 – 1550 cm-1 region.
Fig. SI1(d): Raman spectra of SA19 in D2O and H2O, 850 – 1550 cm-1 region.
Fig. SI2: Plot showing increase in intensity at 1380 cm-1is related to presence of Raman contribution in the O-D stretch region. OD = oven dried from D2O; FD – free dried from D2O.
Fig. SI3: A 6 x6 cellulose crystal model with square cross sectional shape. The model consists of 16 interior (green in [200]) and 20 surface chains.
Fig. SI4: Low frequency Raman spectra of various celluloses that produced cellulose nanocrystals upon acid hydrolysis.
Fig. SI5:XRD full width at half maximum (FWHM) of various samples
Fig. SI 6:Variation of 2θ for [200] diffraction peak
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