Charge-driven interfacial gelation of cellulose nanofibrils across the water/oil interface.
Soft Matter
; 16(2): 357-365, 2020 Jan 02.
Article
en En
| MEDLINE
| ID: mdl-31720672
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.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Idioma:
En
Revista:
Soft Matter
Año:
2020
Tipo del documento:
Article
País de afiliación:
Reino Unido