ISO DIS 21400

Description / Abstract: This International Standard provides procedures for the laboratory determination of the total elemental sulphur and the sulphate half-ester content of cellulose nanocrystals (CNCs) by inductively coupled plasma-optical emission spectroscopy and conductometric titration, respectively, including sample preparation, measurement methods and data analysis. It is the intent for this Standard to apply to the characterization of CNCs (a) having all monovalent counterions (particularly hydronium and sodium cations), (b) which are either in the never-dried state in aqueous suspension, or have been re-dispersed from a dried form, and (c) which have been extracted from any naturally occurring cellulose source using a range of sulphuric acid hydrolysis conditions, or have been sulphated posthydrolysis using sulphuric acid.