A mathematical model describing elastic response of hybrid hydrogel from TEMPO-oxidized cellulose nanofibrils and graphene oxide

Krajnc, Matjaž (avtor), Alič, Branko (avtor), Malnarič, Iris (avtor), Šebenik, Urška (avtor)

This study introduces a mathematical model to elucidate the long-term elastic behavior of hybrid hydrogels, combining TEMPO-oxidized cellulose nanofibrils (TOCNF) and graphene oxide (GO), both in the presence and absence of calcium ions. The model quantifies the influence of hydrogel composition, specifically the TOCNF/GO ratio and calcium ion concentration, on elasticity. The elasticity is precisely measured by the equilibrium shear modulus, derived by fitting experimental data to the generalized Maxwell model. The model's parameters effectively assess the diverse interactions contributing to the hydrogel's overall elasticity. It was found that the elasticity of individual TOCNF and GO hydrogels increases with their respective concentrations, attributable to various interparticle interactions. The incorporation of calcium chloride markedly enhances elasticity through the formation of ionic bridges, which emerge as the dominant factor governing elastic properties. Notably, the efficiency of these ionic crosslinks remains consistent across both TOCNF and GO hydrogels, although the overall elastic contribution is comparatively lower for GO systems. In hybrid TOCNF/GO hydrogels lacking Ca$^{2+}$, negative deviations from standard mixing rules' predictions suggest inhibitory interactions, such as electrostatic repulsion. Conversely, the presence of Ca$^{2+}$ leads to significant positive deviations, indicative of a synergistic effect. Here, calcium ions facilitate crucial crosslinks not only within the individual TOCNF and GO networks but, more importantly, at their interfacial regions. This interfacial bridging substantially enhances the long-term elasticity of the ternary hydrogel system. The developed model accurately quantifies these intricate and complex interactions.

• Jezik: Angleški jezik
• Ključne besede: nanocellulose, TEMPO-oxidized cellulose nanofibrils, graphene oxide, hydrogel, rheology, mathematical model
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Datum objave: 15.11.2025
• Leto izida: 2025
• Št. strani: 12 str.
• Številčenje: Vol. 524, art. 169811
• PID: 20.500.12556/RUL-175295
• UDK: 678.54:620.3
• ISSN pri članku: 1385-8947
• DOI: 10.1016/j.cej.2025.169811
• COBISS.SI-ID: 254509827
• Datum objave v RUL: 23.10.2025

Gradivo je del revije

• Naslov: Chemical engineering journal
• Skrajšan naslov: Chem. eng. j.
• Založnik: Elsevier Sequoia
• ISSN: 1385-8947
• COBISS.SI-ID: 2110998

Licence

• Licenca: CC BY-NC-ND 4.0, Creative Commons Priznanje avtorstva-Nekomercialno-Brez predelav 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc-nd/4.0/deed.sl
• Opis: Najbolj omejujoča licenca Creative Commons. Uporabniki lahko prenesejo in delijo delo v nekomercialne namene in ga ne smejo uporabiti za nobene druge namene.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: nanoceluloza, TEMPO oksidirana celuloza, grafen oksid, hidrogel, reologija, matematični model

Projekti

• Financer: ARIS - Javna agencija za znanstvenoraziskovalno in inovacijsko dejavnost Republike Slovenije
• Številka projekta: P2-0191-2020
• Naslov: Kemijsko inženirstvo