Application Note #158
Swelling of cellulose nanocrystals (CNC) was studied using MP-SPR. Dry and wet films were studied in various solvents to predict dispersibility of the film for composite applications.
Cellulose nanocrystals (CNCs) are rod-shaped nanomaterials utilized in biomedical devices, emulsion stabilizers, rheological modifiers and in various other composite applications. Multi-Parametric Surface Plasmon Resonance (MP-SPR) is a highly sensitive label-free method used to study surface changes. Swelling of CNC films was measured using MP-SPR to probe particle–particle cohesion in the film and thus predict dispersibility of the film. This study focuses on CNC agglomerates which may be present during nanocomposite compounding.
Water swollen CNC films showed a 14 ± 2% increase in thickness when compared to dry CNC films. Organic solvents increased the volume of hydrophilic CNC films less than water: acetone by 4% and methanol, acetonitrile, isopropanol and ethanol in the range of 6 to 8%. The hydrogen bonding ability of the solvent correlated well with film swelling. Nevertheless, highly polar aprotic acetonitrile was equally effective as alcohols.
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- If you are interested in cellulose, you may also view AN#149 about molecular interactions on cellulose characterization using MP-SPR – Adsorption studies and layer thickness, and AN#159 about cellulose in water vapor.
- Have a look at original publication here: Reid et al. (2016)
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