Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue, Waterloo, ON, N2L 3G1, Canada.
Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue, Waterloo, ON, N2L 3G1, Canada.
Carbohydr Polym. 2019 Feb 15;206:520-527. doi: 10.1016/j.carbpol.2018.11.006. Epub 2018 Nov 10.
Cellulose nanocrystals (CNC) are sustainable nanomaterials that possess high tensile strength, stiffness and surface functional groups suitable for various types of modifications. In this study, phosphorylated cellulose nanocrystals (P-CNC) were prepared via acid hydrolysis with phosphoric acid to decorate phosphate groups on the surface of CNC. Also, chitosan was modified with glycidyltrimethylammonium chloride (GTMAC) to improve its solubility. GTMAC-Chitosan (GCh) and phosphorylated cellulose nanocrystals (P-CNC) were complexed via ionic gelation to produce GCh-P-CNC nanoparticles under mild sonication. Although sodium tripolyphosphate (TPP) is a common cross-linking agent used with chitosan, its application is compromised by its metastable structure that resulted in the rapid release of its encapsulated compound. Therefore, phosphorylated cellulose nanocrystal was developed as a "nanoparticle" cross-linker and a Pickering emulsifier. The nanocomplexes transformed from a rod-like to hard sphere and random coil morphology with increasing ratio of GCh/P-CNC. In comparison with TPP-Chitosan emulsion, Pickering emulsion prepared using GCh-P-CNC complex was more stable over 3 months without coalescence and phase separation.
纤维素纳米晶（CNC）是一种可持续的纳米材料，具有高强度、高刚性和表面功能基团，适合进行各种类型的修饰。在这项研究中，通过用磷酸进行酸水解，在 CNC 表面装饰磷酸基团来制备磷酸化纤维素纳米晶（P-CNC）。此外，壳聚糖用氯化 3-（二甲氨基）丙基）甲基（GTMAC）进行修饰以提高其溶解度。通过离子凝胶化将 GTMAC-壳聚糖（GCh）和磷酸化纤维素纳米晶（P-CNC）复合，在温和的超声下产生 GCh-P-CNC 纳米颗粒。尽管三聚磷酸钠（TPP）是一种常用的与壳聚糖交联的交联剂，但由于其亚稳态结构，其应用受到限制，导致其包封化合物的快速释放。因此，开发了磷酸化纤维素纳米晶作为“纳米粒子”交联剂和 Pickering 乳化剂。随着 GCh/P-CNC 比例的增加，纳米复合物从棒状转变为硬球和无规卷曲形态。与 TPP-壳聚糖乳液相比，使用 GCh-P-CNC 复合物制备的 Pickering 乳液在 3 个月内没有聚结和相分离，更加稳定。
