Abstract

Interfacial gels, obtained by the interaction of water-dispersible oxidised cellulose nanofibrils (OCNF) and oil-soluble oleylamine (OA), were produced across water/oil (W/O) interfaces. Surface rheology experiments showed that the complexation relies on the charge coupling between the negatively-charged OCNF and OA. Complexation across the W/O interface was found to be dependent on the ζ-potential of the OCNF (modulated by electrolyte addition), leading to different interfacial properties. Spontaneous OCNF adsorption at the W/O interface occurred for particles with ζ-potential more negative than -30 mV, resulting in the formation of interfacial gels; whilst for particles with ζ-potential of ca. -30 mV, spontaneous adsorption occurred, coupled with augmented interfibrillar interactions, yielding stronger and tougher interfacial gels. On the contrary, charge neutralisation of OCNF (ζ-potential values more positive than -30 mV) did not allow spontaneous adsorption of OCNF at the W/O interface. In the case of favourable OCNF adsorption, the interfacial gel was found to embed oil-rich droplets-a spontaneous emulsification process.
Original languageEnglish
Pages (from-to)357-365
JournalSoft Matter
Volume16
Issue number2
Early online date7 Nov 2019
DOIs
Publication statusPublished - 14 Jan 2020

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    Dataset for Charge-driven interfacial gelation of cellulose nanofibrils across the water/oil interface

    Calabrese, V. (Creator), da Silva, M. (Creator), Schmitt, J. (Creator), Hossain, Z. (Creator), Scott, J. L. (Creator) & Edler, K. (Creator), University of Bath, 7 Nov 2019

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