2026-04-17T00:45:39Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/3405012026-02-07T10:54:03Zcom_2072_1033col_2072_452950

Patience is a virtue: self-assembly and physico-chemical properties of cellulose nanocrystal allomorphs Delepierre, Gwendoline Eyley, Samuel Thielemans, Wim Weder, Christoph Cranston, Emily Zoppe, Justin Orazio Àrees temàtiques de la UPC::Matemàtiques i estadística Cellulose nanocrystals Cel·lulosa Nanocristalls Cellulose nanocrystals (CNCs) are bio-based rod-like nanoparticles with a quickly expanding market. Despite the fact that a variety of production routes and starting cellulose sources are employed, all industrially produced CNCs consist of cellulose I (CNC-I), the native crystalline allomorph of cellulose. Here a comparative study of the physico-chemical properties and liquid crystalline behavior of CNCs produced from cellulose II (CNC-II) and typical CNC-I is reported. CNC-I and CNC-II are isolated by sulfuric acid hydrolysis of cotton and mercerized cotton, respectively. The two allomorphs display similar surface charge densities and ¿-potentials and both have a right-handed twist, but CNC-II have a slightly smaller average length and aspect ratio, and are less hygroscopic. Interestingly, the self-assembly behavior of CNC-I and CNC-II in water is different. Whilst CNC-I forms a chiral nematic phase, CNC-II initially phase separates into an upper isotropic and a lower nematic liquid crystalline phase, before a slow reorganization into a large-pitch chiral nematic texture occurs. This is potentially caused by a combination of factors, including the inferred faster rotational diffusion of CNC-II and the different crystal structures of CNC-I and CNC-II, which are responsible for the presence and absence of a giant dipole moment, respectively. Peer Reviewed Postprint (published version) 2020 Article https://pubs.rsc.org/en/content/articlelanding/2020/NR/D0NR04491A#!divAbstract http://creativecommons.org/licenses/by-nc-nd/3.0/es/ Restricted access - publisher's policy Attribution-NonCommercial-NoDerivs 3.0 Spain