Structural Changes of Water in Carboxymethyl Cellulose Nanofiber Hydrogels during Vapor Swelling and Drying.

ABSTRACT: Carboxymethyl cellulose nanofiber (CMCF) forms mechanically strong hydrogels via freeze cross-linking. We investigated the vapor swelling and drying processes of the freeze cross-linked CMCF hydrogels using infrared spectroscopy and X-ray diffraction. From the shifts of the O-H and C=O stretching modes, the structural changes of water and carboxymethyl celluloses (CMC) were analyzed. The results show that two types of bound water exist in CMCF hydrogels due to a difference in hydrophilicity between the amorphous and crystalline regions of CMCF. Bound water adsorbed on the amorphous region forms a strong hydrogen bond with dangling O-H or C=O bonds of CMC, whereas that adsorbed on the crystalline region has a weak hydrogen bond with the localized hydrophilic groups on the hydrophobic surfac

SUBMITTER: Takahara Y 

PROVIDER: S-EPMC11561596 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature