Understanding heat driven gelation of anionic cellulose nanofibrils: Combining saturation transfer difference (STD) NMR, small angle X-ray scattering (SAXS) and rheology

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:535

Article

Calabrese, Vincenzo¹  Munoz-Garcia, Juan C.²  Schmitt, Julien¹  da Silva, Marcelo A.¹  Scott, Janet L.^1,3  Angulo, Jesus²  Khimyak, Yaroslav Z.²  Edler, Karen J.¹ 

[1] Univ Bath, Dept Chem, Bath BA2 7AY, Avon, England

[2] Univ East Anglia, Sch Pharm, Norwich Res Pk, Norwich NR4 7TJ, Norfolk, England

[3] Univ Bath, Ctr Sustainable Chem Technol, Bath BA2 7AY, Avon, England

关键词: Water confinement;    Hydrogel;    TEMPO oxidised cellulose;    Heat induced gelation;    Saturation transfer difference NMR;    SAXS;    Rheology;   

DOI  :  10.1016/j.jcis.2018.09.085

来源: Elsevier

【 摘 要 】

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 Theological 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. In comparison, cationic cellulose nanofibrils (produced by reaction of cellulose with trimethylglycidylammonium chloride) were found to be heat-unresponsive. (C) 2018 The Authors. Published by Elsevier Inc.

【 授权许可】

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