State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; Bioproducts Institute, Department of Chemical & Biological Engineering, Department of Chemistry, and Department of Wood Science, 2360 East Mall, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FIN-00076 Aalto, Espoo, Finland.
Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FIN-00076 Aalto, Espoo, Finland.
Carbohydr Polym. 2023 Jan 1;299:120154. doi: 10.1016/j.carbpol.2022.120154. Epub 2022 Sep 27.
Pickering emulsions are stabilized using complexes of cellulose nanocrystals (CNC) and nanochitin (NCh). The colloidal behavior and heteroaggregation in aqueous media are studied in relation to complex formation and net charge. The complexes are remarkably effective in stabilizing oil-in-water Pickering emulsions under conditions of slightly net positive or negative charges, as determined by the CNC/NCh mass ratio. Close to charge neutrality (CNC/NCh ~5), large heteroaggregates form, resulting in unstable emulsions. By contrast, under net cationic conditions, interfacial arrest of the complexes leads to non-deformable emulsion droplets with high stability (no creaming for 9 months). At given CNC/NCh concentrations, emulsions with up to 50% oil fraction are produced. This study shows how to control emulsion properties beyond consideration of the typical formulation variables, for instance, through adjusting CNC/NCh ratio or charge stoichiometry. We highlight the possibilities that are available for emulsion stabilization by using a combination of polysaccharide nanoparticles.
Pickering 乳液是通过纤维素纳米晶体 (CNC) 和纳米几丁质 (NCh) 的复合物稳定的。研究了胶体行为和异质聚集在水介质中的关系，与复合物的形成和净电荷有关。在略微带正电荷或负电荷的条件下，通过 CNC/NCh 质量比确定，复合物在稳定油包水 Pickering 乳液方面非常有效。接近电荷中性 (CNC/NCh~5) 时，会形成大的异质聚集物，导致乳液不稳定。相比之下，在带正电荷的条件下，复合物的界面捕获会导致乳液滴具有高稳定性（9 个月内无浮油）。在给定的 CNC/NCh 浓度下，可以制备高达 50%油分的乳液。本研究表明，如何通过调整 CNC/NCh 比例或电荷化学计量比来控制乳液特性，超越典型配方变量的考虑。我们通过使用多糖纳米粒子的组合突出了可用的乳液稳定的可能性。
