Study on temperature-dependent changes in hydrogen bonds in cellulose Iβ by infrared spectroscopy with perturbation-correlation moving-window two-dimensional correlation spectroscopy

Infrared (IR) spectra were measured for cellulose I beta prepared from the mantle of Halocynthia roretzi over a temperature range of 30-260 degrees C to explore the temperature-dependent changes in hydrogen bonds ( H-bonds) in the crystal. Structural changes at the phase transition temperature of 220 C are elucidated at the functional group level by perturbation-correlation moving-window two-dimensional (PCMW2D) correlation spectroscopy. The PCMW2D correlation spectra show that the intensities of bands arising from O3-H3 center dot center dot center dot O5 and O2- H2 center dot center dot center dot O6 intrachain H-bonds dramatically decrease at 220 degrees C, whereas the intensity changes of bands due to interchain H-bonds are not observed adequately. These results suggest that the phase transition is induced by the dissociation of the O3-H3 center dot center dot center dot O5 and O2- H2 center dot center dot center dot O6 intrachain H-bonds. However, the interchain H-bonds are not so much responsible for the transition directly.