Molecular weight-controllable regenerated cellulose nanocrystal for Pickering emulsion application

Abstract

Employing an aqueous NaOH/urea solvent and absolute ethanol as the anti-solvent, regenerated cellulose nanocrystals (RCNC) were fractionated via a multi-step precipitation protocol to yield populations with tunable molecular weights and sequentially reduced yet uniform particle dimensions. Chromatographic and electron-microscopy analyses confirmed that RCNC dimensions scaled inversely with molecular weight across the 36–9 kDa range. Pickering emulsion assays revealed pronounced surfactant-like behaviour for all fractions; the 15 kDa specimen (RCNC-15) outperformed the rest, generating the finest droplet sizes and maintaining maximal stability even at minimal loadings. When this optimal RCNC fraction was employed as a scaffold for in-situ nucleation of zinc oxide nanoparticles, the resulting hybrid catalysed the photodegradation of Nile red within an emulsion medium, attaining 99.5 % decomposition in 100 min and establishing RCNCs as high-efficiency carriers for emulsion-assisted catalytic processes.