ISO/TS 20477:2023

TECHNICAL ISO/TS
SPECIFICATION 20477
Second edition
2023-05
Nanotechnologies — Vocabulary for
cellulose nanomaterial
Nanotechnologies — Vocabulaire pour les nanomatériaux à base de
cellulose
Reference number
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Core nanotechnology terms related to cellulose nanomaterials . 1
3.2 Prerequisite non-nanotechnology terms related to cellulose nanomaterials . 2
3.3 Terms related specifically to cellulose nanomaterials . 3
Annex A (informative) Images of cellulose nanomaterials . 5
Annex B (informative) Cellulose micromaterials . 7
Bibliography . 8
Index . 9
iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all
such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 229, Nanotechnologies.
This second edition cancels and replaces the first edition (ISO/TS 20477:2017), which has been
technically revised.
The main changes are as follows:
— some existing definitions have been revised;
— new terms and definitions have been introduced;
— micrographic images of cellulose nanomaterials have been introduced to illustrate some of the
defined terms.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
Introduction
Cellulose is a polymer produced in nature. In plants, animals, algae and bacteria, cellulose is extruded
from terminal enzyme complexes (TC). TCs are made up of many identical subunits, each containing at
least one catalytic site from which a single cellulose chain is synthesized. Cellulose chains from a single
TC combine to form an elementary fibril. As TCs in plants, animals, algae and bacteria have different
numbers and configurations of subunits, the elementary fibrils they produce have different geometries.
[1]
Whether cellulose nanomaterials are separated by industrial processes or produced directly by
organisms, they all contain a common structural component, which is the elementary fibril. This
common component, the elementary fibril, provides a way to describe cellulose nanomaterials from all
manufacturing methods and cellulose sources.
Cellulose nanomaterials can be manufactured industrially by conversion of wood pulp through chemical,
biological or mechanical processes. Bacterium-based cellulose nanomaterials are produced directly by
bacteria and can be further acid-hydrolysed to smaller dimensions. Besides trees and bacteria, algae are
another potential source of cellulose nanomaterials for industrial applications. Owing to their unique
properties and renewable nature, cellulose nanomaterials have developed into platform materials that
have application potential in a wide range of products including those that currently utilize petroleum-
based ingredients.
At the current stage of development, several terms that describe cellulose nanomaterials coexist and
have created confusion among users. The difficulty of measuring sizes in the low micrometre and
nanometre scale has given rise to confusion in the classification of materials, particularly for the
fibrillate materials. Rather than delaying standards development until knowledge accumulated with
research advancement and market maturity, there is an opportunity to define a standard vocabulary for
cellulose nanomaterials, and for clarity, describe micro-scale cellulose materials, as given in Annex B.
Although terms in the ISO/IEC 80004 series were not developed for specific types of nanomaterials such
as cellulose nanomaterials, to be consistent with existing ISO/TC 229 hierarchy, this document utilizes
terms from the ISO/IEC 80004 series. It is anticipated that as the market for cellulose nanomaterials
matures, so too will the standard vocabulary. Beginning to define a standard vocabulary now will
facilitate future communication, eliminate confusion, remove trade barriers, and provide policy makers
and regulators with a set of consensus-based terms.
v
TECHNICAL SPECIFICATION ISO/TS 20477:2023(E)
Nanotechnologies — Vocabulary for cellulose nanomaterial
1 Scope
This document defines terms and definitions for different types of cellulose nanomaterials including
secondary components found in cellulose nanomaterials originating from their manufacturing
processes. This document also provides information on cellulose micromaterials in Annex B.
Where necessary, terms from the ISO/IEC 80004 series are included in this document. Terms in this
document are applicable to all types of cellulose nanomaterials, regardless of production methods and
their origin (plants, animals, algae or bacteria).
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 Core nanotechnology terms related to cellulose nanomaterials
3.1.1
nanoscale
length range approximately from 1 nm to 100 nm
Note 1 to entry: Properties that are not extrapolations from larger sizes are predominantly exhibited in this
length range.
[SOURCE: ISO/TS 80004-1:2015, 2.1]
3.1.2
nanomaterial
material with any external dimension in the nanoscale (3.1.1) or having internal structure or surface
structure in the nanoscale
Note 1 to entry: This generic term is inclusive of nano-object (3.1.3) and nanostructured material (3.1.5).
Note 2 to entry: See also definitions of engineered nanomaterial, manufactured nanomaterial and incidental
nanomaterial in ISO/TS 80004-1:2015.
[SOURCE: ISO/TS 80004-1:2015, 2.4, modified — Note 2 to entry has been added.]
3.1.3
nan
...