TY - JOUR
T1 - TEMPO-oxidised cellulose nanofibrils; Probing the mechanisms of gelation
T2 - Via small angle X-ray scattering
AU - Schmitt, Julien
AU - Calabrese, Vincenzo
AU - Da Silva, Marcelo A.
AU - Lindhoud, Saskia
AU - Alfredsson, Viveka
AU - Scott, Janet L.
AU - Edler, Karen J.
PY - 2018/6/21
Y1 - 2018/6/21
N2 - The structure of dispersions of TEMPO-oxidised cellulose nanofibrils (OCNF), at various concentrations, in water and in NaCl aqueous solutions, was probed using small angle X-ray scattering (SAXS). OCNF are modelled as rod-like particles with an elliptical cross-section of 10 nm and a length greater than 100 nm. As OCNF concentration increases above 1.5 wt%, repulsive interactions between fibrils are evidenced, modelled by the interaction parameter νRPA > 0. This corresponds to gel-like behaviour, where G′ > G′′ and the storage modulus, G′, shows weak frequency dependence. Hydrogels can also be formed at OCNF concentration of 1 wt% in 0.1 M NaCl(aq). SAXS patterns shows an increase of the intensity at low angle that is modelled by attractive interactions (νRPA < 0) between OCNF, arising from the screening of the surface charge of the fibrils. Results are supported by ζ potential and cryo-TEM measurements.
AB - The structure of dispersions of TEMPO-oxidised cellulose nanofibrils (OCNF), at various concentrations, in water and in NaCl aqueous solutions, was probed using small angle X-ray scattering (SAXS). OCNF are modelled as rod-like particles with an elliptical cross-section of 10 nm and a length greater than 100 nm. As OCNF concentration increases above 1.5 wt%, repulsive interactions between fibrils are evidenced, modelled by the interaction parameter νRPA > 0. This corresponds to gel-like behaviour, where G′ > G′′ and the storage modulus, G′, shows weak frequency dependence. Hydrogels can also be formed at OCNF concentration of 1 wt% in 0.1 M NaCl(aq). SAXS patterns shows an increase of the intensity at low angle that is modelled by attractive interactions (νRPA < 0) between OCNF, arising from the screening of the surface charge of the fibrils. Results are supported by ζ potential and cryo-TEM measurements.
UR - http://www.scopus.com/inward/record.url?scp=85048518901&partnerID=8YFLogxK
U2 - 10.1039/c8cp00355f
DO - 10.1039/c8cp00355f
M3 - Article
AN - SCOPUS:85048518901
SN - 1463-9076
VL - 20
SP - 16012
EP - 16020
JO - Physical chemistry chemical physics
JF - Physical chemistry chemical physics
IS - 23
ER -