Understanding heat driven gelation of anionic cellulose nanofibrils: Combining Saturation Transfer Difference (STD) NMR, Small Angle X-ray Scattering (SAXS) and rheology

DOI: 10.1016/j.jcis.2018.09.085

Authors: Vincenzo Calabrese (University of Bath) , Juan C. Muñoz-García (University of East Anglia) , Julien Schmitt (University of Bath) , Marcelo A. Da Silva (University of Bath) , Janet L. Scott (University of Bath) , Jesús Angulo (University of East Anglia) , Yaroslav Z. Khimyak (University of East Anglia) , Karen Edler (University of Bath)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Colloid And Interface Science

State: Published (Approved)
Published: September 2018
Diamond Proposal Number(s): 163641

Abstract: A novel mechanism of heat-triggered gelation for oxidised cellulose nanofibrils (OCNF) is reported. We demonstrate that a synergistic approach combining rheology, small-angle X-ray scattering (SAXS) and saturation transfer difference NMR (STD NMR) experiments enables a detailed characterisation of gelation at different length scales. OCNF dispersions experience an increase in solid-like behaviour upon heating as evidenced by rheological studies, associated with enhanced interfibrillar interactions measured using SAXS. Interactions result in an increased fibrillar overlap and increased population of confined water molecules monitored by STD NMR. By comparison, cationic cellulose nanofibrils (produced by reaction of cellulose with trimethylglycidylammonium chloride) were found to be heat-unresponsive.

Journal Keywords: Water confinement; hydrogel; TEMPO oxidised cellulose; heat induced gelation; saturation transfer difference NMR; SAXS; rheology

Subject Areas: Chemistry, Materials


Instruments: I22-Small angle scattering & Diffraction

Added On: 26/09/2018 09:35

Documents:
1-s2.0-S0021979718311603-main.pdf

Discipline Tags:

Soft condensed matter physics Chemistry Materials Science Polymer Science

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS)