ISO 21400:2018 PDF

Scope: This document specifies procedures for the laboratory determination of the total elemental sulfur and the sulfate 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. This document is applicable to the characterization of CNCs: a) with all monovalent counterions (particularly hydronium and sodium cations); b) which are either in the never-dried state in aqueous suspension, or have been redispersed from a dried form; and c) which have been extracted from any naturally occurring cellulose source using a range of sulfuric acid hydrolysis conditions, or have been sulfated post-hydrolysis using sulfuric acid.

ISO 21400:2018 Referenced Document

ISO 14644-1 Cleanrooms and associated controlled environments - Part 1: Classification of air cleanliness by particle concentration (includes Redline Version)
ISO 3696 Water for analytical laboratory use; Specification and test methods
ISO/TS 80004-1 Nanotechnologies - Vocabulary - Part 1: Core terms
ISO/TS 80004-2 Nanotechnologies - Vocabulary - Part 2: Nano-objects
ISO/TS 80004-6 Nanotechnologies - Vocabulary - Part 6: Nano-object characterization*， 2021-03-01 Update

2018 ISO 21400:2018 Pulp — Determination of cellulose nanocrystal sulfur and sulfate half-ester content