ISO 6031:2025

Functional extenders for special application — Nanoscale diamonds for polymer composites

This document specifies requirements and corresponding test methods for nanoscale diamond as a functional additive in polymer composites.

Titre manque

General Information

• Status: Published
• Publication Date: 06-Jul-2025
• ICS: 87.060.10 - Pigments and extenders
• Technical Committee: ISO/TC 256 - Pigments, dyestuffs and extenders
• Drafting Committee: ISO/TC 256 - Pigments, dyestuffs and extenders
• Current Stage: 6060 - International Standard published
• Start Date: 07-Jul-2025
• Due Date: 19-Jul-2025
• Completion Date: 04-Jul-2025

Standards Content (Sample)

International
Standard
ISO 6031
First edition
Functional extenders for special
2025-07
application — Nanoscale diamonds
for polymer composites
Reference number
© ISO 2025
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: [phone]
Email: [e-mail]
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
4 Abbreviated terms . 2
5 Classification and designation . 3
5.1 Classification .3
5.2 Designation .3
6 Requirements and test methods . 4
6.1 Appearance .4
6.2 Technical requirements and test methods .4
7 Sampling . 5
8 Marking and labelling . 5
9 Test report . 6
Annex A (informative) Examples of basic characteristics and test methods of nanoscale
diamonds in liquid or solid dispersion . 7
Bibliography . 8

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 256, Pigments, dyestuffs and extenders.
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
Diamond is a solid carbon material with a cubic crystal structure, within which each atom is covalently
bonded to four neighbouring atoms forming a regular tetrahedron. This dense packing of carbon atoms
determines the following unique properties of diamond:
— the highest hardness and wear resistance,
— the highest thermal conductivity and high electrical resistivity,
— high refractive index and wide band gap,
— chemical and radiation resistance,
— high biocompatibility.
Nanoscale diamonds, also called nanodiamonds or ultradispersed diamonds, were first discovered in the
Soviet Union in 1963 in a detonation blend obtained by the explosion of a trotyl-hexogen charges in a big,
closed metal detonation chamber in air environment without any additional carbon source. Since then, they
[4][5][6]
have been carefully studied and have become commercially available. At the time of publication of
this document, nanodiamonds are obtained by the detonation of explosives, by laser-induced synthesis from
carbon soot, as well as by crushing and milling microdiamonds. Their main industrial applications include
fine polishing and lapping, antifriction lubrication and electroplating. They are also used as functional
additives to varnishes, paints and adhesives, thermal compounds and other composite materials.
Nanoscale diamonds have an average primary particle size of less than 100 nm. In case of detonation or laser
synthesis, most of them are smaller than 10 nm while their average size usually does not exceed 5 nm. Unlike
ordinary diamonds, a single nanodiamond particle has a complex structure, consisting of an inert diamond
core and a reactive shell of hybrid fullerene-like or amorphous carbon with various functional groups on the
surface (carbonyl, carboxyl, hydroxyl, amine, amide, ether, etc.). Nanodiamonds have a large surface area (up
2 3
to 600 m /g) and a low bulk density (up to 1 g/cm ). They usually aggregate strongly, forming agglomerates
several micrometres in size.
Ready-to-use functional nanodiamond extenders can be supplied in the form of a powder with specially
modified surface that provides disaggregation of nanodiamonds when they are introduced into a specific
production process and mixed. In addition, functional extenders can be supplied in the form of concentrated
dispersions of disaggregated nanodiamonds based on solvents, polymer resins and plastics.
To be used as a functional extender for application in polymer composites, nanoscale diamonds are provided
in powder form or disaggregated and uniformly distributed in a polymer matrix or in a liquid.
Nanoscale diamond uniformly dispersed in polymers can improve polymers in terms of their strength, wear
resistance, flexibility, thermal conductivity, thermal stability, radiation resistance and other functional
properties.
v
International Standard ISO 6031:2025(en)
Functional extenders for special application — Nanoscale
diamonds for polymer composites
1 Scope
This document specifies requirements and corresponding test methods for nanoscale diamond as a
functional additive in polymer composites.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 787-9, General methods of test for pigments and extenders — Part 9: Determination of pH value of an
aqueous suspension
ISO 3262-1, Extenders — Specifications and methods of test — Part 1: Introduction and general test methods
ISO 4618, Paints and varnishes — Vocabulary
ISO 9277, Determination of the specific surface area of solids by gas adsorption — BET method
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
ISO 18451-1, Pigments, dyestuffs and extenders — Terminology — Part 1: General terms
ISO 80004-1, Nanotechnologies – Vocabulary — Part 1: Core vocabulary
IEC/TS 62607-4-6, Nanomanufacturing — Key control characteristics — Part 4-6: Nano-enabled electrical energy
storage — Determination of carbon content for nano-enabled electrode materials, infrared absorption method
IEC/TS 62607-6-13, Nanomanufacturing — Key control characteristics — Part 6-13: Graphene-based
material — Oxygen functional group content: Boehm titration method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618, ISO 18451-1, ISO 80004-1
and the following 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
nanoscale diamonds
nanodiamonds
engineered carbon nanomaterials with cubic crystalline structure
Note 1 to entry: Nanoscale diamonds are normally produced by detonation of explosives in metal chambers, by
physical crushing and milling of natural diamonds or microdiamonds produced by a high-pressure high-temperature
(HPHT) process or by laser treatment of a hydrocarbon compound.

Note 2 to entry: After synthesis or milling, nanodiamonds can be subject to the process of surface modification for
specific applications.
Note 3 to entry: The properties of the materials strongly depend on the production process.
3.2
detonation nanodiamonds
DND
nanoscale diamonds (3.1) synthesized by detonation of explosives, usually having the average size of primary
particles of 4 nm to 5 nm
3.3
high-pressure high-temperature nanodiamonds
HPHTND
nanoscale diamonds (3.1) produced through crushing and milling synthetic microdiamonds obtained by
high-pressure high-temperature (HPHT) synthesis, usually having the average size of primary particles of
30 nm to 100 nm
3.4
laser nanodiamonds
LND
nanoscale diamonds (3.1) produced by laser treatment of a hydrocarbon compound, having an average size of
primary particles of 4 nm to 5 nm
3.5
surface modification
process including purification, if necessary, and surface functionalization of nanoscale diamonds (3.1) to be
compatible with polymers and other materials
3.6
nanodispersion
material in which nano-objects are dispersed in a continuous phase of a different composition
Note 1 to entry: Nanodispersions comprise nanosuspensions and nanoemulsions.
Note 2 to entry: Gaseous matrices are excluded (solid and liquid drops in gases are “aerosols”).
[SOURCE: ISO 18451-1:2019, 3.79]
4 Abbreviated terms
DND detonation nanodiamonds
DND-LDPE-4 4 % (mass fraction) DND dispersed in low density polyethylene
DND-OH hydroxylated DND
DND-W-10 DND dispersed in water in the concentration of 10 % (mass fraction)
FTIR Fourier transform infrared spectroscopy
HPHTND high-pressure high-temperature nanodiamonds
HPHTND-Ep-5 HPHTND in the concentration of 5 % (mass fraction) dispersed in epoxy resin
HPHTND-NH aminated HPHTND
HPHTND-PA66-3 3 % (mass fraction) HPHTND dispersed in polyamide-66 respectively
ICP inductively coupled plasma spectrometry
...

International
Standard
ISO 6031
First edition
Functional extenders for special
application — Nanoscale diamonds
for polymer composites
PROOF/ÉPREUVE
Reference number
© ISO 2025
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: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
PROOF/ÉPREUVE
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Classification and designation . 3
5.1 Classification .3
5.2 Designation .3
6 Requirements and test methods . 4
6.1 Appearance .4
6.2 Technical requirements and test methods .4
7 Sampling . 5
8 Marking and labelling . 5
9 Test report . 6
Annex A (informative) Examples of basic characteristics and test methods of nanoscale
diamonds in liquid or solid dispersion . 7
Bibliography . 8
PROOF/ÉPREUVE
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 256, Pigments, dyestuffs and extenders.
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.
PROOF/ÉPREUVE
iv
Introduction
Diamond is a solid carbon material with a cubic crystal structure, within which each atom is covalently
bonded to four neighbouring atoms forming a regular tetrahedron. This dense packing of carbon atoms
determines the following unique properties of diamond:
— the highest hardness and wear resistance,
— the highest thermal conductivity and high electrical resistivity,
— high refractive index and wide band gap,
— chemical and radiation resistance,
— high biocompatibility.
Nanoscale diamonds, also called nanodiamonds or ultradispersed diamonds, were first discovered in the
Soviet Union in 1963 in a detonation blend obtained by the explosion of a trotyl-hexogen charges in a big,
closed metal detonation chamber in air environment without any additional carbon source. Since then, they
[4][5][6]
have been carefully studied and have become commercially available. At the time of publication of
this document, nanodiamonds are obtained by the detonation of explosives, by laser-induced synthesis from
carbon soot, as well as by crushing and milling microdiamonds. Their main industrial applications include
fine polishing and lapping, antifriction lubrication and electroplating. They are also used as functional
additives to varnishes, paints and adhesives, thermal compounds and other composite materials.
Nanoscale diamonds have an average primary particle size of less than 100 nm. In case of detonation or laser
synthesis, most of them are smaller than 10 nm while their average size usually does not exceed 5 nm. Unlike
ordinary diamonds, a single nanodiamond particle has a complex structure, consisting of an inert diamond
core and a reactive shell of hybrid fullerene-like or amorphous carbon with various functional groups on the
surface (carbonyl, carboxyl, hydroxyl, amine, amide, ether, etc.). Nanodiamonds have a large surface area (up
2 3
to 600 m /g) and a low bulk density (up to 1 g/cm ). They usually aggregate strongly, forming agglomerates
several micrometres in size.
Ready-to-use functional nanodiamond extenders can be supplied in the form of a powder with specially
modified surface that provides disaggregation of nanodiamonds when they are introduced into a specific
production process and mixed. In addition, functional extenders can be supplied in the form of concentrated
dispersions of disaggregated nanodiamonds based on solvents, polymer resins and plastics.
To be used as a functional extender for application in polymer composites, nanoscale diamonds are provided
in powder form or disaggregated and uniformly distributed in a polymer matrix or in a liquid.
Nanoscale diamond uniformly dispersed in polymers can improve polymers in terms of their strength, wear
resistance, flexibility, thermal conductivity, thermal stability, radiation resistance and other functional
properties.
PROOF/ÉPREUVE
v
International Standard ISO 6031:2025(en)
Functional extenders for special application — Nanoscale
diamonds for polymer composites
1 Scope
This document specifies requirements and corresponding test methods for nanoscale diamond as a
functional additive in polymer composites.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 787-9, General methods of test for pigments and extenders — Part 9: Determination of pH value of an
aqueous suspension
ISO 3262-1, Extenders — Specifications and methods of test — Part 1: Introduction and general test methods
ISO 4618, Paints and varnishes — Vocabulary
ISO 9277, Determination of the specific surface area of solids by gas adsorption — BET method
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
ISO 18451-1, Pigments, dyestuffs and extenders — Terminology — Part 1: General terms
ISO 80004-1, Nanotechnologies – Vocabulary — Part 1: Core vocabulary
IEC/TS 62607-4-6, Nanomanufacturing — Key control characteristics — Part 4-6: Nano-enabled electrical energy
storage — Determination of carbon content for nano-enabled electrode materials, infrared absorption method
IEC/TS 62607-6-13, Nanomanufacturing — Key control characteristics — Part 6-13: Graphene-based
material — Oxygen functional group content: Boehm titration method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618, ISO 18451-1, ISO 80004-1
and the following 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
nanoscale diamonds
nanodiamonds
engineered carbon nanomaterials with cubic crystalline structure
Note 1 to entry: Nanoscale diamonds are normally produced by detonation of explosives in metal chambers, by
physical crushing and milling of natural diamonds or microdiamonds produced by a high-pressure high-temperature
(HPHT) process or by laser treatment of a hydrocarbon compound.
PROOF/ÉPREUVE
Note 2 to entry: After synthesis or milling, nanodiamonds can be subject to the process of surface modification for
specific applications.
Note 3 to entry: The properties of the materials strongly depend on the production process.
3.2
detonation nanodiamonds
DND
nanoscale diamonds (3.1) synthesized by detonation of explosives, usually having the average size of primary
particles of 4 nm to 5 nm
3.3
high-pressure high-temperature nanodiamonds
HPHTND
nanoscale diamonds (3.1) produced through crushing and milling synthetic microdiamonds obtained by
high-pressure high-temperature (HPHT) synthesis, usually having the average size of primary particles of
30 nm to 100 nm
3.4
laser nanodiamonds
LND
nanoscale diamonds (3.1) produced by laser treatment of a hydrocarbon compound, having an average size of
primary particles of 4 nm to 5 nm
3.5
surface modification
process including purification, if necessary, and surface functionalization of nanoscale diamonds (3.1) to be
compatible with polymers and other materials
3.6
nanodispersion
material in which nano-objects are dispersed in a continuous phase of a different composition
Note 1 to entry: Nanodispersions comprise nanosuspensions and nanoemulsions.
Note 2 to entry: Gaseous matrices are excluded (solid and liquid drops in gases are “aerosols”).
[SOURCE: ISO 18451-1:2019, 3.79]
4 Abbreviated terms
DND detonation nanodiamonds
DND-LDPE-4 4 % (mass fraction) DND dispersed in low density polyethylene
DND-OH hydroxylated DND
DND-W-10 DND dispersed in water in the concentration of 10 % (mass fraction)
FTIR Fourier transform infrared spectroscopy
HPHTND high-pressure high-temperature nanodiamonds
HPHTND-Ep-5 HPHTND in the concentration of 5 % (mass fraction) dispersed in epoxy resin
HPHTND-NH aminated HPHTND
HPHTND-PA66-3 3 % (mass fraction) HPHTND dispersed in polyamide-66 respectively
ICP inductively coupled plasma spectrometry
PROOF/ÉPREUVE
...

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Functional extenders for special application — Nanoscale diamonds
at: 0 cm, Tab stops: Not at 0.63 cm
for polymer composites
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ISO/PRF 6031:2025(en)
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
Formatted: English (United Kingdom)
Phone: + 41 22 749 01 11
E-mail: [e-mail]
Website: www.iso.org
Formatted: English (United Kingdom)
Formatted: English (United Kingdom)
Published in Switzerland
Formatted: English (United Kingdom)

Formatted: English (United Kingdom)
ii
ISO/PRF 6031:2025(en)
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Classification and designation. 3
5.1 Classification . 3
5.2 Designation . 3
6 Requirements and test methods . 4
6.1 Appearance . 4
6.2 Technical requirements and test methods . 4
7 Sampling . 5
8 Marking and labelling . 5
9 Test report . 6
Annex A (informative) Examples of basic characteristics and test methods of nanoscale
diamonds in liquid or solid dispersion . 7
Bibliography . 8

Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Classification and designation. 3
6 Requirements and test methods . 4
7 Sampling . 5
8 Marking and labelling . 5
9 Test report . 6
Annex A (informative) Examples of basic characteristics and test methods of nanoscale
diamonds in liquid or solid dispersion . 7
Bibliography . 8

iii
ISO/PRF 6031:2025(en)
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).
Formatted: English (United Kingdom)
Formatted: English (United Kingdom)
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.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.htmlwww.iso.org/iso/foreword.html.
Formatted: English (United Kingdom)
This document was prepared by Technical Committee ISO/TC 256, Pigments, dyestuffs and extenders.
Any feedback or questions on this document should be directed to the user’s national standards body. A
Formatted: English (United Kingdom)
complete listing of these bodies can be found at www.iso.org/members.htmlwww.iso.org/members.html.
Formatted: English (United Kingdom)

iv
ISO/PRF 6031:2025(en)
Introduction
Diamond is a solid carbon material with a cubic crystal structure, within which each atom is covalently bonded
to four neighbouring atoms forming a regular tetrahedron. This dense packing of carbon atoms determines
the following unique properties of diamond:
— the highest hardness and wear resistance,
Formatted: List Continue 1, No bullets or numbering
— the highest thermal conductivity and high electrical resistivity,
— high refractive index and wide band gap,
— chemical and radiation resistance,
— high biocompatibility.
Nanoscale diamonds, also called nanodiamonds or ultradispersed diamonds, were first discovered in the
Soviet Union in 1963 in a detonation blend obtained by the explosion of a trotyl-hexogen charges in a big,
closed metal detonation chamber in air environment without any additional carbon source. Since then, they
[4][5][6]
have been carefully studied and have become commercially available . At the time of publication of this
document, nanodiamonds are obtained by the detonation of explosives, by laser-induced synthesis from
carbon soot, as well as by crushing and milling of microdiamonds. Their main industrial applications include
fine polishing and lapping, antifriction lubrication and electroplating. They are also used as functional
additives to varnishes, paints and adhesives, thermal compounds, and other composite materials.
Nanoscale diamonds have an average primary particle size of less than 100 nm. In case of detonation or laser
synthesis, most of them are smaller than 10 nm while their average size usually does not exceed 5 nm. Unlike
ordinary diamonds, a single nanodiamond particle has a complex structure, consisting of an inert diamond
core and a reactive shell of hybrid fullerene-like or amorphous carbon with various functional groups on the
surface (carbonyl, carboxyl, hydroxyl, amine, amide, ether, etc.). Nanodiamonds have a large surface area (up
2 3
to 600 m /g) and a low bulk density (up to 1 g/cm ). They usually aggregate strongly, forming agglomerates
several micrometres in size.
Ready-to-use functional nanodiamond extenders can be supplied in the form of a powder with specially
modified surface that provides disaggregation of nanodiamonds when they are introduced into a specific
production process and mixed. In addition, functional extenders can be supplied in the form of concentrated
dispersions of disaggregated nanodiamonds based on solvents, polymer resins and plastics.
To be used as a functional extender for application in polymer composites, nanoscale diamonds are provided
in powder form or disaggregated and uniformly distributed in a polymer matrix or in a liquid.
Nanoscale diamond uniformly dispersed in polymers can improve polymers in terms of their strength, wear
resistance, flexibility, thermal conductivity, thermal stability, radiation resistance and other functional
properties.
v
ISO/PRF 6031:2025(en)
Functional extenders for special application — Nanoscale diamonds
for polymer composites
1 Scope
This document specifies requirements and corresponding test methods for nanoscale diamond as a functional
additive in polymer composites.
2 Normative references
The following documents are re
...