Nicolet is10 ftir spectrometer

¹H NMR and ¹³C NMR spectra were recorded with JEOL 400 and 600 MHz FT‐NMR spectrometers (Tokyo, Japan) by using [D₆]DMSO or CDCl₃ as the solvent. The DS value with respect to the propionate unit in the chlorinated sample was calculated from the ¹H NMR spectrum by integrating the signal areas of the proton signals of the cellulose backbone (I_{3.4–5.5 ppm}) and the proton signals of the propionate methyl group (I_{0.5‐1.3 ppm}) as follows [Eq. (1)]: ${\displaystyle \mathrm{DS}{}_{\mathrm{propionate}}=\frac{(I{}_{0.5\text{-}1.3\mathrm{ppm}}\times 7)}{(I{}_{3.4-5.5\mathrm{ppm}}\times 3)}}$
The DS value with respect to the azido group was determined from elemental analysis performed with a Micro Order JM10 Organic Elemental Micro Analyzer (J‐Science Lab Co., Ltd., Kyoto, Japan).
FTIR spectra were obtained by using a Thermo Scientific Nicolet iS10 FTIR spectrometer (Waltham, MA, USA) and a GladiATR accessory (Pike Technologies, Madison, WI, USA). An average of 128 scans was taken with a resolution of 2 cm⁻¹.

Cellulose derivatives were characterized by ¹H and ¹³C-NMR spectroscopy in DMSO-d₆ or CDCl₃ as a solvent using a JEOL 400 and 600 MHz FT-NMR spectrometer (Tokyo, Japan). Quantitative ¹³C-NMR measurement was carried out at room temperature with 30 seconds pulse-repetition time and with a scan number of 2000. FTIR spectra were recorded on a Thermo Scientific Nicolet iS10 FTIR spectrometer (Waltham, MA, USA) equipped with a GladiATR accessory (Pike Technologies, Madison, WI, USA) applying a scan number of 128 and a resolution of 2 cm⁻¹.