Three types of nanocelluloses, including bacterial cellulose (BC), cellulose nanofiber (CNF) and cellulose nanocrystal (CNC), were used to prepare oil-in-water Pickering emulsions with the objective to disclose the effect of fiber flexibility on emulsification. In aqueous suspensions, the shortest CNC is rigid, while the longest BC fully flexible, which result in large difference in their dilute-to-semi-dilute concentrations, and in the rheological percolations. Thus, these cellulosic nanofibers play different roles during emulsification. Flexible BC nearly has no emulsifying capacity, whereas semi-flexible CNF and rigid CNC can be well used to stabilize emulsions. For the CNF-stabilized system, depletion effect is dominant, leading to the formation of droplet clusters easily, while for the CNC-stabilized one, repulsive effect plays more important role. Visible evidence regarding relaxation of long-term structure of droplets is further disclosed by dynamic rheology. This work proposes interesting views around tailoring morphology and viscoelasticity of Pickering emulsions by regulating fiber flexibility.

三种类型nanocelluloses的，包括细菌纤维素（BC），纤维素纳米纤维（CNF）和纤维素纳米晶体（CNC），用于制备油中-水Pickering乳液，目的是公开的纤维柔韧性上乳化的效果。在水性悬浮液中，最短的CNC是刚性的，而最长的BC是完全柔性的，这导致它们的稀释度差异很大。-半稀释浓度，流变渗透。因此，这些纤维素纳米纤维在乳化过程中起着不同的作用。柔性BC几乎没有乳化能力，而半柔性CNF和刚性CNC可以很好地用于稳定乳液。对于CNF稳定的系统，耗尽效应占主导地位，容易导致液滴簇的形成；而对于CNC稳定的系统，排斥效应起着更重要的作用。动态流变学进一步公开了有关液滴长期结构松弛的可见证据。这项工作提出了关于通过调节纤维柔韧性来调整Pickering乳液的形态和粘弹性的有趣观点。