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

Cite this

@article{531fa48c545a46a9a0f0f95e3534581d,
title = "Charge-driven interfacial gelation of cellulose nanofibrils across the water/oil interface",
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.",
author = "Vincenzo Calabrese and {da Silva}, Marcelo and Julien Schmitt and Zakir Hossain and Scott, {Janet L} and Edler, {Karen J}",
year = "2020",
month = "1",
day = "14",
doi = "10.1039/C9SM01551E",
language = "English",
volume = "16",
pages = "357--365",
journal = "Soft Matter",
issn = "1744-683X",
publisher = "Royal Society of Chemistry",
number = "2",

}

TY - JOUR

T1 - Charge-driven interfacial gelation of cellulose nanofibrils across the water/oil interface

AU - Calabrese, Vincenzo

AU - da Silva, Marcelo

AU - Schmitt, Julien

AU - Hossain, Zakir

AU - Scott, Janet L

AU - Edler, Karen J

PY - 2020/1/14

Y1 - 2020/1/14

N2 - 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.

AB - 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.

U2 - 10.1039/C9SM01551E

DO - 10.1039/C9SM01551E

M3 - Article

VL - 16

SP - 357

EP - 365

JO - Soft Matter

JF - Soft Matter

SN - 1744-683X

IS - 2

ER -