Amine Sarah, Montembault Alexandra, Fumagalli Matthieu, Osorio-Madrazo Anayancy, David Laurent
Ingénierie des Matériaux Polymères IMP UMR 5223-CNRS, Université Claude Bernard Lyon 1, Université de Lyon, 69622 Villeurbanne, France.
Laboratory for Sensors, Institute of Microsystems Engineering-IMTEK, University of Freiburg, 79110 Freiburg, Germany.
Polymers (Basel). 2021 Jun 21;13(12):2023. doi: 10.3390/polym13122023.
We prepared chitosan (CHI) hydrogels reinforced with highly charged cellulose nanofibrils (CNF) by the desalting method. To this end, the screening of electrostatic interactions between CHI polycation and CNF polyanion was performed by adding NaCl at 0.4 mol/L to the chitosan acetate solution and to the cellulose nanofibrils suspension. The polyelectrolyte complexation between CHI polycation and CNF polyanion was then triggered by desalting the CHI/CNF aqueous mixture by multistep dialysis, in large excess of chitosan. Further gelation of non-complexed CHI was performed by alkaline neutralization of the polymer, yielding high reinforcement effects as probed by the viscoelastic properties of the final hydrogel. The results showed that polyelectrolyte association by desalting can be achieved with a polyanionic nanoparticle partner. Beyond obtaining hydrogel with improved mechanical performance, these composite hydrogels may serve as precursor for dried solid forms with high mechanical properties.
我们通过脱盐法制备了用高电荷纤维素纳米纤维（CNF）增强的壳聚糖（CHI）水凝胶。为此，通过向壳聚糖醋酸盐溶液和纤维素纳米纤维悬浮液中添加0.4 mol/L的NaCl，对CHI聚阳离子与CNF聚阴离子之间的静电相互作用进行了筛选。然后，通过多步透析对大量过量壳聚糖的CHI/CNF水性混合物进行脱盐，引发CHI聚阳离子与CNF聚阴离子之间的聚电解质络合。通过聚合物的碱性中和对未络合的CHI进行进一步凝胶化，最终水凝胶的粘弹性性能表明产生了高增强效果。结果表明，脱盐的聚电解质缔合可以与聚阴离子纳米颗粒伙伴实现。除了获得具有改善机械性能的水凝胶外，这些复合水凝胶还可以用作具有高机械性能的干燥固体形式的前体。
