SIST EN ISO 11337:2023
(Main)Plastics - Polyamides - Determination of ε-caprolactam and ω-laurolactam by gas chromatography (ISO 11337:2023)
Plastics - Polyamides - Determination of ε-caprolactam and ω-laurolactam by gas chromatography (ISO 11337:2023)
ISO 11337:2010 specifies a method for determining epsilon‑caprolactam and omega‑laurolactam in polyamides by gas chromatography. It is suitable particularly for the determination of epsilon‑caprolactam in polyamide 6 and omega‑laurolactam in polyamide 12. Bearing in mind that gas chromatography offers a wide range of possible conditions, the method specified is that shown to have been suitable in practice.
Two variants of the basic method are specified:
Method A is an extraction method with boiling methanol, and the extract is injected into a gas chromatograph.
Method B is a method using a solvent, and the solution is injected into a gas chromatograph.
Kunststoffe - Polyamide - Gaschromatographische Bestimmung von ε-Caprolactam und ω-Laurolactam (ISO 11337:2023)
Dieses Dokument legt ein gaschromatographisches Verfahren zur Bestimmung des ε Caprolactamgehaltes und des ω-Laurolactamgehaltes in Polyamiden fest. Es ist besonders zur Bestimmung von ε Caprolactam in Polyamid 6 und von ω Laurolactam in Polyamid 12 anwendbar.
Zwei Varianten des Basisverfahrens sind festgelegt.
Verfahren A ist ein Extraktionsverfahren unter Anwendung von siedendem Methanol, bei dem das Extrakt in einen Gaschromatographen injiziert wird.
Verfahren B ist ein Verfahren unter Anwendung eines Lösemittels, bei dem die Lösung in einen Gaschromatographen injiziert wird.
SICHERHEITSHINWEIS — Anwender dieses Dokuments sollten mit der üblichen Laborpraxis, sofern zutreffend, vertraut sein. Dieses Dokument beabsichtigt nicht alle mit seiner Anwendung verbundenen Sicherheitsprobleme, soweit solche vorhanden sind, anzusprechen. Es liegt in der Verantwortung des Anwenders, geeignete Sicherheits- und Gesundheitsschutzmaßnahmen zu treffen und zutreffende gesetzliche Beschränkungen vor der Anwendung zu bestimmen.
Plastiques - Polyamides - Détermination du ε-caprolactame et du ω-laurolactame par chromatographie en phase gazeuse (ISO 11337:2023)
L'ISO 11337:2010 spécifie une méthode de dosage du epsilon-caprolactame et du omega-laurolactame dans les polyamides par chromatographie en phase gazeuse. Elle convient particulièrement au dosage du epsilon-caprolactame dans le polyamide 6 et du omega-laurolactame dans le polyamide 12. Compte tenu du fait que la chromatographie en phase gazeuse présente un large éventail de conditions possibles, la méthode spécifiée est celle qui a fait ses preuves dans la pratique.
Deux variantes de la méthode de base sont spécifiées:
Méthode A, par extraction au méthanol en ébullition, où les extraits sont injectés dans un chromatographe en phase gazeuse.
Méthode B, utilisant un solvant, où la solution est injectée directement dans un chromatographe en phase gazeuse.
Polimerni materiali - Poliamidi - Določanje ε-kaprolaktama in ω-laurolaktama s plinsko kromatografijo (ISO 11337:2023)
Standard ISO 11337:2010 določa metodo za določanje epsilon-kaprolaktama in omega-laurolaktama v poliamidih s plinsko kromatografijo. Primeren je zlasti za določanje epsilon-kaprolaktama v poliamidu 6 in omega-laurolaktama v poliamidu 12. Glede na to, da plinska kromatografija ponuja širok razpon možnih pogojev, se je v praksi izkazalo, da je navedena metoda primerna.
Določeni sta dve različici osnovne metode:
Metoda A je metoda ekstrakcije z vrelim metanolom, ekstrakt pa se vbrizga v plinski kromatograf.
Metoda B je metoda z uporabo topila, raztopina pa se vbrizga v plinski kromatograf.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 11337:2023
01-april-2023
Polimerni materiali - Poliamidi - Določanje ε-kaprolaktama in ω-laurolaktama s
plinsko kromatografijo (ISO 11337:2023)
Plastics - Polyamides - Determination of ε-caprolactam and ω-laurolactam by gas
chromatography (ISO 11337:2023)
Kunststoffe - Polyamide - Gaschromatographische Bestimmung von ε-Caprolactam und
ω-Laurolactam (ISO 11337:2023)
Plastiques - Polyamides - Détermination du ε-caprolactame et du ω-laurolactame par
chromatographie en phase gazeuse (ISO 11337:2023)
Ta slovenski standard je istoveten z: EN ISO 11337:2023
ICS:
83.080.20 Plastomeri Thermoplastic materials
SIST EN ISO 11337:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 11337:2023
---------------------- Page: 2 ----------------------
SIST EN ISO 11337:2023
EN ISO 11337
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2023
EUROPÄISCHE NORM
ICS 83.080.20 Supersedes EN ISO 11337:2010
English Version
Plastics - Polyamides - Determination of e-caprolactam
and ¿-laurolactam by gas chromatography (ISO
11337:2023)
Plastiques - Polyamides - Détermination du e- Kunststoffe - Polyamide - Gaschromatographische
caprolactame et du ¿-laurolactame par Bestimmung von e-Caprolactam und ¿-Laurolactam
chromatographie en phase gazeuse (ISO 11337:2023) (ISO 11337:2023)
This European Standard was approved by CEN on 6 January 2023.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11337:2023 E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 11337:2023
EN ISO 11337:2023 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 4 ----------------------
SIST EN ISO 11337:2023
EN ISO 11337:2023 (E)
European foreword
This document (EN ISO 11337:2023) has been prepared by Technical Committee ISO/TC 61 "Plastics"
in collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by
NBN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by August 2023, and conflicting national standards shall
be withdrawn at the latest by August 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 11337:2010.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 11337:2023 has been approved by CEN as EN ISO 11337:2023 without any modification.
3
---------------------- Page: 5 ----------------------
SIST EN ISO 11337:2023
---------------------- Page: 6 ----------------------
SIST EN ISO 11337:2023
INTERNATIONAL ISO
STANDARD 11337
Third edition
2023-01
Plastics — Polyamides —
Determination of ε-caprolactam and
ω-laurolactam by gas chromatography
Plastiques — Polyamides — Détermination du ε-caprolactame et du
ω-laurolactame par chromatographie en phase gazeuse
Reference number
ISO 11337:2023(E)
© ISO 2023
---------------------- Page: 7 ----------------------
SIST EN ISO 11337:2023
ISO 11337:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© 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
© ISO 2023 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 11337:2023
ISO 11337:2023(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Method A: Extraction method .1
4.1 Principle . 1
4.2 Reagents . 1
4.3 Apparatus and materials . 2
4.4 Preparation of test sample . 3
4.5 Procedure . 4
4.5.1 Test portion . 4
4.5.2 Extraction . 4
4.5.3 Preparation of internal-standard solution . 4
4.5.4 Preparation of sample solution . 4
4.5.5 Preparation of calibration solution . 4
4.5.6 Gas-chromatographic analysis of sample and calibration solutions . 4
4.5.7 Evaluation of gas chromatographic peaks . 5
4.6 Expression of results . . 5
4.7 Precision . . . 5
4.8 Test report . 6
5 Method B: Dissolution method . 6
5.1 Principle . 6
5.2 Reagents . 6
5.3 Apparatus . 7
5.4 Preparation of internal-standard solutions . 8
5.4.1 General . 8
5.4.2 Internal standard for unextracted polyamide 6 . 8
5.4.3 Internal standard for extracted polyamide 6 . 8
5.4.4 Internal standard for polyamide 12 . 8
5.4.5 Preparation of calibration solutions . 9
5.4.6 Calibration . . . 10
5.5 Procedure . 10
5.5.1 Preparation and injection of sample solution . 10
5.5.2 Evaluation of gas-chromatographic peaks. 10
5.5.3 Solvent recovery . 10
5.6 Expression of results . . 11
5.7 Precision . . . 11
5.8 Test report . 11
iii
© ISO 2023 – All rights reserved
---------------------- Page: 9 ----------------------
SIST EN ISO 11337:2023
ISO 11337:2023(E)
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
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 61, Plastics, Subcommittee SC 9,
Thermoplastic materials, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 249, Plastics, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 11337:2010), which has been technically
revised.
The main changes are as follows:
— isopropanol has been added as suitable internal standard for method A;
— the use of packed and capillary columns has been indicated specifically;
— the specification of suitable detectors has been opened.
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
© ISO 2023 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 11337:2023
INTERNATIONAL STANDARD ISO 11337:2023(E)
Plastics — Polyamides — Determination of ε-caprolactam
and ω-laurolactam by gas chromatography
SAFETY STATEMENT — Persons using this document should be familiar with normal laboratory
practice, if applicable. This document does not purport to address all of the safety concerns, if
any, associated with its use. It is the responsibility of the user to establish appropriate safety
and health practices and determine the applicability of regulatory limitations prior to use.
1 Scope
This document specifies a method for determining ε-caprolactam and ω-laurolactam in polyamides by
gas chromatography. It is applicable particularly to the determination of ε-caprolactam in polyamide 6
and ω-laurolactam in polyamide 12.
Two variants of the basic method are specified.
— Method A is an extraction method with boiling methanol, and the extract is injected into a gas
chromatograph.
— Method B is a method using a solvent, and the solution is injected into a gas chromatograph.
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 amendment) applies.
ISO 472, Plastics — Vocabulary
ISO 565, Test sieves — Metal wire cloth, perforated metal plate and electroformed sheet — Nominal sizes
of openings
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 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/
4 Method A: Extraction method
4.1 Principle
A test portion is extracted with boiling methanol and a small volume of the extract is injected into a
gas chromatograph equipped with a suitable detector to separate and detect the volatile components.
The extract contains 1-dodecanol as an internal standard.
4.2 Reagents
During the analysis, use only reagents of recognized analytical grade.
1
© ISO 2023 – All rights reserved
---------------------- Page: 11 ----------------------
SIST EN ISO 11337:2023
ISO 11337:2023(E)
4.2.1 Solvent, such as methanol.
4.2.2 Internal standard, such as 1-dodecanol or isopropanol.
4.2.3 ε-Caprolactam.
4.3 Apparatus and materials
Ordinary laboratory apparatus, plus the following.
4.3.1 Mill, for reducing the sample to the required grain size.
A mill in which the sample is ground at a low temperature is preferred. Large pieces may be reduced in
size with a pair of scissors before they are fed to the mill.
4.3.2 Two sieves, with aperture sizes of 710 µm and 500 µm, respectively, in accordance with the
requirements of ISO 565.
4.3.3 Extraction apparatus, that can accommodate an extraction crucible or porous ceramic thimble
containing the test portion.
The apparatus shall be of such a design that the crucible or thimble is heated by the rising methanol
vapour or the apparatus shall be constructed of an extraction flask with a Soxhlet-type reflux condenser.
Examples of suitable extraction apparatus designed along these lines are
EXAMPLE 1
— 250 ml extraction flask;
— extraction chamber to accommodate the extraction crucible so that it is enveloped on all sides by the rising
methanol vapour and the condensed methanol drips through it continuously;
— glass triangle to support the crucible;
— reflux condenser;
— sintered-glass filter crucible, pore size 40 µm to 50 µm, capacity 30 ml;
— porcelain filter-plate of slightly smaller diameter than the crucible, with holes of diameter 0,4 mm.
EXAMPLE 2
— 250 ml extraction flask;
— jacketed Soxhlet extractor;
— reflux condenser;
— sintered-glass filter crucible, pore size 40 µm to 50 µm, capacity 30 ml, or a porous ceramic thimble of similar
capacity (the dimensions shall be such that the crucible or thimble can be satisfactorily accommodated in the
Soxhlet apparatus);
— porcelain filter-plate of slightly smaller diameter than the crucible or thimble, as appropriate, with holes of
diameter 0,4 mm.
4.3.4 Heating device, suitable heating device for extraction apparatus.
4.3.5 Analytical balance, accurate to ±0,2 mg.
4.3.6 Liquid nitrogen or solid carbon dioxide, if necessary.
2
© ISO 2023 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 11337:2023
ISO 11337:2023(E)
4.3.7 Gas chromatograph, with suitable detector.
Both, packed and capillary columns may be used.
a) Column
The following columns are suitable:
1)
— a packed column, e.g. a glass column (3 mm Ø × 1,6 m), packed with acid-washed Chromosorb® W
of particle diameter 0,149 mm to 0,177 mm (80 mesh to 100 mesh) coated with 10 % (by mass)
poly(ethylene glycol) 20M;
TM1)
— a capillary column, e.g. a megabore Carbowax column (0,53 mm Ø × 15 m), of corresponding
separation efficiency.
The method of packing is not specified but shall be such as to obtain satisfactory separation efficiency.
Other column dimensions may be used as long as a sufficient separation efficiency is achieved.
A capillary column may also be used.
Suggested operating conditions for using a glass column and an FID detector are shown in Table 1.
a
Table 1 — Operating conditions for gas chromatograph with packed column and FID detector
Item Value
Column temperature 200 °C
Injector temperature 250 °C
Detector temperature 250 °C
Carrier gas Helium or nitrogen
Carrier gas flow rate 20 ml/min
a
These values apply to the packed column indicated in 4.3.7 a)
Other types of columns and/or detectors can require different operating temperatures and types and
flow rates of carrier and makeup gas.
b) Detector
Use a suitable detector with adequate selection of operating t
...
SLOVENSKI STANDARD
oSIST prEN ISO 11337:2022
01-september-2022
Polimerni materiali - Poliamidi - Določanje e-kaprolaktama in w-laurolaktama s
plinsko kromatografijo (ISO/DIS 11337:2022)
Plastics - Polyamides - Determination of e-caprolactam and w-laurolactam by gas
chromatography (ISO/DIS 11337:2022)
Kunststoffe - Polyamide - Gaschromatographische Bestimmung von ε-Caprolactam und
ω-Laurolactam (ISO/DIS 11337:2022)
Plastiques - Polyamides - Détermination du e-caprolactame et du w-laurolactame par
chromatographie en phase gazeuse (ISO/DIS 11337:2022)
Ta slovenski standard je istoveten z: prEN ISO 11337
ICS:
83.080.20 Plastomeri Thermoplastic materials
oSIST prEN ISO 11337:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN ISO 11337:2022
---------------------- Page: 2 ----------------------
oSIST prEN ISO 11337:2022
DRAFT INTERNATIONAL STANDARD
ISO/DIS 11337
ISO/TC 61/SC 9 Secretariat: KATS
Voting begins on: Voting terminates on:
2022-06-09 2022-09-01
Plastics — Polyamides — Determination of e-caprolactam
and w-laurolactam by gas chromatography
Plastiques — Polyamides — Détermination du e-caprolactame et du w-laurolactame par chromatographie
en phase gazeuse
ICS: 83.080.20
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
ISO/CEN PARALLEL PROCESSING
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 11337:2022(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022
---------------------- Page: 3 ----------------------
oSIST prEN ISO 11337:2022
ISO/DIS 11337:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
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
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
oSIST prEN ISO 11337:2022
ISO/DIS 11337:2022(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Method A: Extraction method .1
4.1 Principle . 1
4.2 Reagents . 2
4.3 Apparatus and materials . 2
4.4 Preparation of test sample . 3
4.5 Procedure . 4
4.5.1 Test portion . 4
4.5.2 Extraction . 4
4.5.3 Preparation of internal-standard solution . 4
4.5.4 Preparation of sample solution . 4
4.5.5 Preparation of calibration solution . 4
4.5.6 Gas-chromatographic analysis of sample and calibration solutions . 4
4.5.7 Evaluation of gas chromatographic peaks . 5
4.6 Expression of results . . 5
4.7 Precision . . . 5
4.8 Test report . 6
5 Method B: Dissolution method . 6
5.1 Principle . 6
5.2 Reagents . 6
5.3 Apparatus . 7
5.4 Preparation of internal-standard solutions . 8
5.4.1 General . 8
5.4.2 Internal standard for unextracted polyamide 6 . 8
5.4.3 Internal standard for extracted polyamide 6 . 8
5.4.4 Internal standard for polyamide 12 . 8
5.4.5 Preparation of calibration solutions . 8
5.4.6 Calibration . . . 9
5.5 Procedure . 10
5.5.1 Preparation and injection of sample solution . 10
5.5.2 Evaluation of gas-chromatographic peaks. 10
5.5.3 Solvent recovery . 10
5.6 Expression of results . . 10
5.7 Precision . . . 11
5.8 Test report . 11
iii
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
oSIST prEN ISO 11337:2022
ISO/DIS 11337:2022(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International
Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies
casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 11337 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 5, Physical-
chemical properties.
This second edition cancels and replaces the first edition (ISO 11337:2004), which has been technically
revised. It also incorporates the Technical Corrigendum ISO 11337:2004/Cor.1:2007.
iv
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
oSIST prEN ISO 11337:2022
DRAFT INTERNATIONAL STANDARD ISO/DIS 11337:2022(E)
Plastics — Polyamides — Determination of e-caprolactam
and w-laurolactam by gas chromatography
SAFETY STATEMENT — Persons using this document should be familiar with normal laboratory
practice, if applicable. This document does not purport to address all of the safety concerns, if
any, associated with its use. It is the responsibility of the user to establish appropriate safety
and health practices and to ensure compliance with any regulatory requirements.
1 Scope
This document specifies a method for determining ε-caprolactam and ω-laurolactam in polyamides by
gas chromatography. It is applicable particularly to the determination of ε-caprolactam in polyamide 6
and ω-laurolactam in polyamide 12.
Two variants of the basic method are specified:
— Method A is an extraction method with boiling methanol, and the extract is injected into a gas
chromatograph.
— Method B is a method using a solvent, and the solution is injected into a gas chromatograph.
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 amendment)
applies.
ISO 472, Plastics — Vocabulary
ISO 565, Test sieves — Metal wire cloth, perforated metal plate and electroformed sheet — Nominal sizes
of openings
3 Terms and definitions
For the purposes for this document, the terms and definitions given in ISO 472 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
4 Method A: Extraction method
4.1 Principle
A test portion is extracted with boiling methanol and a small volume of the extract injected into a gas
chromatograph equipped with a suitable detector to separate and detect the volatile components.
The extract contains 1-dodecanol as an internal standard.
1
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
oSIST prEN ISO 11337:2022
ISO/DIS 11337:2022(E)
4.2 Reagents
During the analysis, use only reagents of recognized analytical grade.
4.2.1 Solvent such as methanol.
4.2.2 Internal standard such as 1-dodecanol or isopropanol.
4.2.3 ε-Caprolactam.
4.3 Apparatus and materials
Ordinary laboratory apparatus, plus the following:
4.3.1 Mill, for reducing the sample to the required grain size.
A mill in which the sample is ground at a low temperature is preferred. Large pieces can be reduced in
size with a pair of scissors before they are fed to the mill.
4.3.2 Two sieves, with aperture sizes of 710 µm and 500 µm respectively, complying with the
requirements of ISO 565.
4.3.3 Extraction apparatus, that will accommodate an extraction crucible or porous ceramic
thimble containing the test portion.
The apparatus shall be of such a design that the crucible or thimble is heated by the rising methanol
vapour or the apparatus shall be constructed of an extraction flask with a Soxhlet-type reflux condenser.
Examples of suitable extraction apparatus designed along these lines are
EXAMPLE 1
— 250 ml extraction flask;
— extraction chamber to accommodate the extraction crucible so that it is enveloped on all sides by
the rising methanol vapour and the condensed methanol drips through it continuously;
— glass triangle to support the crucible;
— reflux condenser;
— sintered-glass filter crucible, pore size 40 µm to 50 µm, capacity 30 ml;
— porcelain filter-plate of slightly smaller diameter than the crucible, with holes of diameter 0,4 mm.
EXAMPLE 2
— 250 ml extraction flask;
— jacketed Soxhlet extractor;
— reflux condenser;
— sintered-glass filter crucible, pore size 40 µm to 50 µm, capacity 30 ml, or a porous ceramic thimble
of similar capacity (the dimensions shall be such that the crucible or thimble can be satisfactorily
accommodated in the Soxhlet apparatus);
— porcelain filter-plate of slightly smaller diameter than the crucible or thimble, as appropriate, with
holes of diameter 0,4 mm.
2
© ISO 2022 – All rights reserved
---------------------- Page: 8 ----------------------
oSIST prEN ISO 11337:2022
ISO/DIS 11337:2022(E)
4.3.4 Suitable heating device for extraction apparatus.
4.3.5 Analytical balance, accurate to 0, 2 mg.
4.3.6 Liquid nitrogen or solid carbon dioxide, if necessary.
4.3.7 Gas chromatograph, with suitable detector.
a) Column
The following columns are suitable:
1)
— a glass column (3 mm Æ × 1,6 m), packed with acid-washed Chromosorb® W of particle diameter
0,149 mm to 0,177 mm (80 mesh to 100 mesh) coated with 10 % (by mass) poly(ethylene glycol)
20M;
TM1)
— a megabore Carbowax column (0,53 mm Æ × 15 m) of corresponding separation efficiency.
The method of packing is not specified but shall be such as to obtain satisfactory separation efficiency.
Other column dimensions may be used as long as a sufficient separation efficiency is achieved.
A capillary column may also be used.
Suggested operating conditions for using a glass column and a FID detector are shown in Table 1.
Table 1 — Operating conditions for gas chromatograph
Item Value
Column temperature 200 °C
Injector temperature 250 °C
Detector temperature 250 °C
Carrier gas Helium or nitrogen
Carrier gas flow rate 20 ml/min
Other types of columns and/or detectors may require different operating temperatures and types and
flow rates of carrier and makeup gas.
b) Detector
Use a suitable detector with adequate selection of operating temperature and type and flow rate of
carrier and makeup gas so that:
— the sensitivity is high;
— the relationship between response and concentration is linear over the whole measurement range;
— small changes in flow rate produce only insignificant effects on response and sensitivity.
4.3.8 Microsyringes, with capacities from 1 µl to 10 µl.
4.4 Preparation of test sample
Take a representative sample of the polymer and grind it in the mill (4.3.1). Grind the material in small
portions to prevent undue heat development (i.e. to avoid the temperature rising above about 40 °C),
letting the mill cool down in between portions. Solid carbon dioxide or liquid nitrogen (4.3.6) may be
1) Examples of suitable products available commercially. This information is given for the convenience of users of
this International Standard and does not constitute an endorsement by ISO of these products.
3
© ISO 2022 – All rights reserved
---------------------- Page: 9 ----------------------
oSIST prEN ISO 11337:2022
ISO/DIS 11337:2022(E)
ground together with the polymer to prevent heat build-up. With a large mill having a greater heat
capacity, these precautions may not be required. Collect the fraction that passes through a sieve with
mesh aperture 710 µm (4.3.2), but not through the one with mesh aperture 500 µm.
4.5 Procedure
4.5.1 Test portion
Weigh, to the nearest 0,001 g, (5 ± 0,5) g (mass m ) of the test sample into the filter crucible or porous
0
thimble (4.3.3). With low-concentration samples, it is preferable to increase the mass of the test portion
so that it contains approximately 0,01 g to 0,05 g of ε-caprolactam.
NOTE Polyamides can contain a small amount of water, forming part of the mass of the test portion (m ).
0
This water is not allowed for in the calculation of the methanol-extractable matter content since its effect is small
compared the variance of the determination.
4.5.2 Extraction
Cover the test portion (see 4.5.1) with the filter-plate, pour about 50 ml of methanol (4.2.1) into the
extraction flask, place the crucible or thimble containing the test portion in the extraction chamber and
fit the condenser to the chamber. Heat the solvent in the flask to boiling. When the apparatus described
in 4.3.3, Example 1, is used, a
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.