Gel permeation chromatography (GPC) - Part 1: Tetrahydrofuran (THF) as eluent (ISO 13885-1:2020)

This document specifies the determination of the molar-mass distribution and the average molar mass values Mn (number average) and Mw (weight average) of polymers that are soluble in tetrahydrofuran (THF) by gel permeation chromatography (GPC).
NOTE   Also known as size exclusion chromatography (SEC).
Even though the chromatograms obtained show good repeatability, it is possible that this method cannot be used with certain polymer types because of specific interactions (e.g. adsorption) within the sample/eluent/column system.
The conditions specified in this document are not applicable to the GPC analysis of polymer samples with Mw values greater than 106 g/mol and/or of polymers with elution limits outside the calibration range (see 7.6 and Annex C).
This document includes no correction method (e.g. for the elimination of peak broadening. If absolute molar-mass values are required, an absolute method (e.g. membrane osmometry for Mn or light scattering for Mw) can be used.

Gelpermeationschromatographie (GPC) - Teil 1: Tetrahydrofuran (THF) als Elutionsmittel (ISO 13885-1:2020)

Dieses Dokument legt die Ermittlung der Molmassenverteilung und der Molmassenmittelwerte Mn (Zahlenmittel) und Mw (Gewichtsmittel) von in Tetrahydrofuran (THF) löslichen Polymeren durch Gelpermeationschromatographie (GPC) fest.
ANMERKUNG Im Englischen auch als „size exclusion chromatography“ (SEC), übersetzt „Größenausschluss-chromatographie“, bekannt.
Auf Grund spezifischer Wechselwirkungen (z. B. Adsorption) in dem System aus Probe/Elutionsmittel/Trennmaterial ist es möglich, dass dieses Verfahren trotz guter Wiederholbarkeit der resultierenden Chromatogramme auf einzelne Polymere nicht angewandt werden kann.
Die in diesem Dokument festgelegten Bedingungen sind nicht anwendbar bei GPC-Analysen von Polymerproben mit Mw-Werten größer 106 g/mol und/oder von Polymeren, deren Elutionsgrenzen außerhalb des Kalibrierbereiches liegen (siehe 7.6 und Anhang C).
Dieses Dokument umfasst keine Korrekturverfahren (z. B. Elimination der Peakverbreiterung). Wenn absolute Molmassenwerte benötigt werden, kann auf ein Absolutverfahren (z. B. Membranosmometrie für Mn oder Lichtstreuung für Mw) zurückgegriffen werden.
WARNUNG - Dieses Dokument kann den Umgang mit gefährlichen Substanzen und Ausrüstungsteilen und die Ausführung gefährlicher Arbeitsgänge einschließen. Es erhebt nicht den Anspruch, auf alle gegebenenfalls vorhandenen und mit seiner Anwendung verbundenen Sicherheitsprobleme hinzuweisen. Es liegt in der Verantwortung des Anwenders, geeignete Vorkehrungen für den Arbeits‑ und Gesundheitsschutz zu treffen und die Übereinstimmung mit jeglichen nationalen Bestimmungen sicherzustellen.

Chromatographie par perméation de gel (GPC) - Partie 1: Utilisation de tétrahydrofurane (THF) comme éluant (ISO 13885-1:2020)

Gelska permeacijska kromatografija (GPC) - 1. del: Tetrahidrofuran (THF) kot izpiralna tekočina (eluent) (ISO 13885-1:2020)

General Information

Status
Published
Public Enquiry End Date
01-Jun-2021
Publication Date
11-Oct-2021
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Oct-2021
Due Date
06-Dec-2021
Completion Date
12-Oct-2021

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SLOVENSKI STANDARD
SIST EN ISO 13885-1:2021
01-november-2021
Gelska permeacijska kromatografija (GPC) - 1. del: Tetrahidrofuran (THF) kot
izpiralna tekočina (eluent) (ISO 13885-1:2020)

Gel permeation chromatography (GPC) - Part 1: Tetrahydrofuran (THF) as eluent (ISO

13885-1:2020)

Gelpermeationschromatographie (GPC) - Teil 1: Tetrahydrofuran (THF) als Elutionsmittel

(ISO 13885-1:2020)

Chromatographie par perméation de gel (GPC) - Partie 1: Utilisation de tétrahydrofurane

(THF) comme éluant (ISO 13885-1:2020)
Ta slovenski standard je istoveten z: EN ISO 13885-1:2021
ICS:
87.060.20 Veziva Binders
SIST EN ISO 13885-1:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN ISO 13885-1:2021
---------------------- Page: 2 ----------------------
SIST EN ISO 13885-1:2021
EN ISO 13885-1
EUROPEAN STANDARD
NORME EUROPÉENNE
September 2021
EUROPÄISCHE NORM
ICS 87.060.20
English Version
Gel permeation chromatography (GPC) - Part 1:
Tetrahydrofuran (THF) as eluent (ISO 13885-1:2020)

Chromatographie par perméation de gel (GPC) - Partie Gelpermeationschromatographie (GPC) - Teil 1:

1: Utilisation de tétrahydrofurane (THF) comme éluant Tetrahydrofuran (THF) als Elutionsmittel (ISO 13885-

(ISO 13885-1:2020) 1:2020)
This European Standard was approved by CEN on 23 August 2021.

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, Turkey 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

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13885-1:2021 E

worldwide for CEN national Members.
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SIST EN ISO 13885-1:2021
EN ISO 13885-1:2021 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 13885-1:2021
EN ISO 13885-1:2021 (E)
European foreword

The text of ISO 13885-1:2020 has been prepared by Technical Committee ISO/TC 35 "Paints and

varnishes” of the International Organization for Standardization (ISO) and has been taken over as

EN ISO 13885-1:2021 by Technical Committee CEN/TC 139 “Paints and varnishes” the secretariat of

which is held by DIN.

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 March 2022, and conflicting national standards shall

be withdrawn at the latest by March 2022.

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.

Any feedback and questions on this document should be directed to the users’ national standards body.

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, Turkey and the

United Kingdom.
Endorsement notice

The text of ISO 13885-1:2020 has been approved by CEN as EN ISO 13885-1:2021 without any

modification.
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SIST EN ISO 13885-1:2021
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SIST EN ISO 13885-1:2021
INTERNATIONAL ISO
STANDARD 13885-1
Third edition
2020-07
Gel permeation chromatography
(GPC) —
Part 1:
Tetrahydrofuran (THF) as eluent
Chromatographie par perméation de gel (GPC) —
Partie 1: Utilisation de tétrahydrofurane (THF) comme éluant
Reference number
ISO 13885-1:2020(E)
ISO 2020
---------------------- Page: 7 ----------------------
SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

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 2020 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 2

5 Apparatus ..................................................................................................................................................................................................................... 2

5.1 Eluent supply ............................................................................................................................................................................................ 2

5.2 Pump ................................................................................................................................................................................................................ 3

5.3 Injection system ..................................................................................................................................................................................... 3

5.4 Separation columns ............................................................................................................................................................................ 3

5.5 Column temperature control ...................................................................................................................................................... 5

5.6 Detector ......................................................................................................................................................................................................... 5

6 Reagents ........................................................................................................................................................................................................................ 5

7 Calibration of the apparatus .................................................................................................................................................................... 6

7.1 General ........................................................................................................................................................................................................... 6

7.2 Requirements for the calibration standards ................................................................................................................. 6

7.3 Preparation of the calibration solutions for injection ........................................................................................... 7

7.4 Conditions for calibration runs ................................................................................................................................................. 7

7.5 Measurement of elution volume .............................................................................................................................................. 7

7.6 Plotting the calibration curve ..................................................................................................................................................... 7

8 Sampling ........................................................................................................................................................................................................................ 8

9 Preparation for the test ................................................................................................................................................................................. 8

9.1 Preparation of the injection solution ................................................................................................................................... 8

9.2 Preparation of the apparatus ...................................................................................................................................................... 9

10 Analytical parameters ..................................................................................................................................................................................... 9

11 Data acquisition and evaluation ........................................................................................................................................................... 9

11.1 General ........................................................................................................................................................................................................... 9

11.2 Calculation of the net chromatogram from the raw data ................................................................................10

11.2.1 Determination of the baseline ...........................................................................................................................10

11.2.2 Correction of the measured values and of the net chromatogram ....................................10

11.2.3 Evaluation limits ...........................................................................................................................................................10

11.3 Calculation of the average values .........................................................................................................................................10

11.4 Calculation of the distribution curves ..............................................................................................................................11

12 Precision ....................................................................................................................................................................................................................12

12.1 General ........................................................................................................................................................................................................12

12.2 Repeatability ..........................................................................................................................................................................................12

12.3 Reproducibility ....................................................................................................................................................................................12

13 Test report ................................................................................................................................................................................................................13

13.1 General ........................................................................................................................................................................................................13

13.2 General data on the equipment and settings .............................................................................................................13

13.2.1 Data on the equipment used ...............................................................................................................................13

13.2.2 Calibration ..........................................................................................................................................................................13

13.2.3 Evaluation ...........................................................................................................................................................................14

13.3 Special data on the sample ........................................................................................................................................................14

Annex A (informative) Conversion of experimental parameters for variant column sizes ......................16

Annex B (informative) Example of a data sheet for a polymer standard .....................................................................17

Annex C (informative) Explanations ..................................................................................................................................................................18

© ISO 2020 – All rights reserved iii
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SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)

Bibliography .............................................................................................................................................................................................................................23

iv © ISO 2020 – All rights reserved
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SIST EN ISO 13885-1:2021
ISO 13885-1:2020(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 35, Paints and varnishes.

This third edition cancels and replaces the second edition (ISO 13885-1:2008), which has been

technically revised. The main changes compared to the previous edition are as follows:

— this document has been adapted to the actual state of the art, especially with regards to software

engineering;
— the scope has been revised;
— the definition for gel-permeation chromatography has been revised;
— the text has been revised editorially.
A list of all parts in the ISO 13885 series can be found on the ISO website.

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.
© ISO 2020 – All rights reserved v
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SIST EN ISO 13885-1:2021
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SIST EN ISO 13885-1:2021
INTERNATIONAL STANDARD ISO 13885-1:2020(E)
Gel permeation chromatography (GPC) —
Part 1:
Tetrahydrofuran (THF) as eluent

WARNING — This document can involve hazardous materials, operations or equipment. It

does not purport to address all of the safety problems, 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 national regulatory conditions.
1 Scope

This document specifies the determination of the molar-mass distribution and the average molar mass

values M (number average) and M (weight average) of polymers that are soluble in tetrahydrofuran

n w
(THF) by gel permeation chromatography (GPC).
NOTE Also known as size exclusion chromatography (SEC).

Even though the chromatograms obtained show good repeatability, it is possible that this method

cannot be used with certain polymer types because of specific interactions (e.g. adsorption) within the

sample/eluent/column system.

The conditions specified in this document are not applicable to the GPC analysis of polymer samples

with M values greater than 10 g/mol and/or of polymers with elution limits outside the calibration

range (see 7.6 and Annex C).

This document includes no correction method (e.g. for the elimination of peak broadening. If absolute

molar-mass values are required, an absolute method (e.g. membrane osmometry for M or light

scattering for M ) can be used.
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 1513, Paints and varnishes — Examination and preparation of test samples
ISO 4618, Paints and varnishes — Terms and definitions

ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 4618 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
© ISO 2020 – All rights reserved 1
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SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)
3.1
gel permeation chromatography
GPC

separation of molecules, mainly based on exclusion effects such as differences in the size and/or shape

of molecules (size exclusion chromatography) or in charge (ion exclusion chromatography)

3.2
system peak

signal peculiar to the gel permeation chromatography (3.1) using a refractive index detector

Note 1 to entry: These signals appear at the total penetration limit of the columns and are not part of the sample,

but of the overall system.
4 Principle

The dissolved (molecularly disperse) molecules of a polymer sample are fractionated on a porous

column material, with separation taking place according to the size of the molecule (or, more precisely,

the polymer coil size which forms in this eluent). Small molecules diffuse into the pores of the column

material more frequently and are therefore retarded more than large molecules. Thus, large molecules

are eluted earlier, small molecules later. Under the test conditions given, the elution volume is solely a

function of the coil size of the molecule.

The polymer content of a sample is determined, the sample is then diluted with eluent to give a

concentration of less than 5 g/l and an aliquot of the diluted sample is injected into the GPC system. The

concentration of the molecules eluted from the column is measured in order of decreasing coil size with

a concentration-sensitive detector (typically a differential refractometer). With the aid of a calibration

curve that has been determined for the particular GPC system, the relative molar-mass distribution, the

relative quantities M and M and the heterogeneity or polydispersity M /M are calculated from the

n w w n
chromatogram obtained.
5 Apparatus

The apparatus shall consist of the components shown in Figure 1, which are described below.

All the components which come into contact with the eluent or the sample solution shall be resistant

and shall not exhibit adsorption or memory effects in any form. The individual components of the GPC

apparatus, which in this case uses THF as eluent, shall be connected to capillary tubes made of high-

quality steel or titanium.
Figure 1 — Block diagram of a GPC apparatus
5.1 Eluent supply

The eluent reservoir shall adequately protect the eluent against external influences such as the

atmosphere and light, if necessary by means of a blanket of inert gas above the liquid level.

The eluent reservoir shall contain a sufficient quantity of the eluent to bring the apparatus to

equilibrium and to carry out several repeat analyses.
2 © ISO 2020 – All rights reserved
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SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)

The eluent shall be degassed, either before it is introduced into the reservoir or by use of a device fitted

between the reservoir and the pump, to prevent malfunctions of the pump or the formation of bubbles

in the detector. The method of degassing used (e.g. bubble trap, online purging with helium, or vacuum

degassing) is open to choice.
5.2 Pump

The pump shall ensure that the eluent flow through the separation column is as smooth and pulse free

as possible. The flow rate shall be 1 ml/min (see Annex A). To fulfil these requirements, the pump shall

operate at optimum efficiency at this flow rate.
The flow rate of the pump used shall have a variation of max. 0,1 %.
5.3 Injection system

The injection system serves to introduce a given amount of the sample solution into the eluent stream

in a rapid and smooth fashion. This introduction may be carried out either manually or automatically.

If the introduction is carried out manually, ensure that the sample loop is filled completely with solvent

before loading with the sample.

Memory effects from the previous sample solution in the injection system shall be avoided by adequate

flushing.
5.4 Separation columns

The apparatus shall have one or more columns connected in series and packed with spherical porous

material, the diameter of the pores corresponding to the size of the polymer molecules being analysed.

The packing material typically consists of a styrene/divinylbenzene copolymer (S/DVB), produced by

a special polymerization process, which swells only slightly in the solvent and therefore cannot deform

under the pressure developed at the set flow rate.

In addition to these macroporous spherical S/DVB particles, packing materials based on other organic

monomers or on silicon dioxide (silica) are also used. The criterion for their use is that no adsorptive

interaction shall occur between their surface and the polymer molecules in the sample. Furthermore,

the sample being analysed shall not be changed, either chemically or structurally, within the

chromatographic system.

Certain polymers interact with the surface of the packing material (e.g. by adsorption) and other effects

can sometimes interfere with the GPC separation mechanism. Details of such effects and notes on

possible remedies are discussed in Annex C. If it is intended to compare analyses of such polymers by

different laboratories, the laboratories shall agree on details of the test conditions that are not covered

by this document.

For good repeatability of test results, it is necessary to adhere to the minimum requirements specified

below with regard to peak broadening (expressed in terms of a number of theoretical plates) and

separation efficiency.
a) Number of theoretical plates

The number of theoretical plates, N, shall be determined, for the apparatus used per metre of

column used, from the peak width at half height (see Figure 2). Inject up to 20 µl of ethylbenzene

(mass concentration 1 g/l) on to the column (see Annex A) and evaluate the chromatogram obtained

under the same conditions as are used for analysing polymers, using Formula (1):
© ISO 2020 – All rights reserved 3
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SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)
 
100
N =×55, 4   × (1)
 
1/2
 
where
V is the elution volume at the peak maximum;

W is the peak width at half height (see Figure 2); the same units shall be used for V and W ;

1/2 e 1/2
L is the length of the column (column combination), in centimetres.

Express as the result the number of theoretical plates per metre of column length. To conform to the

requirements of this document, the column combination shall have at least 20 000 theoretical plates

per metre.

NOTE See Annex C for tailing and fronting (asymmetry) of the peak used to calculate the plate count.

Key
X elution volume
Y peak intensity
1 injection
V elution volume at the peak maximum
W peak width at the half maximum height of the peak
1/2
h maximum peak height
σ standard deviation

Figure 2 — Determination of the number of theoretical plates by the half-height method

b) Separation efficiency

To ensure adequate resolution, the log M versus the elution volume, V , calibration curve for the

10 e

column combination used shall not exceed a specified gradient. For the purposes of this document,

the relation given in Formula (2) shall apply to the area of the peak maximum for the polymer

sample under investigation:
VV−
e,M e, 10×M
x x
>60, (2)
where
4 © ISO 2020 – All rights reserved
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SIST EN ISO 13885-1:2021
ISO 13885-1:2020(E)
V is the elution volume for polystyrene of molar mass M , in cubic centimetres;
e,M
V is the elution volume for 10 times that molar mass, in cubic centimetres;
e,10×M
A is the cross-sectional area of the column, in square centimetres.

M is the molar mass, that shall be selected such that the peak maximum for the poly-

mer sample under investigation lies in approximately halfway between these two
elution volumes.
5.5 Column temperature control

Carry out the test at room temperature (15 °C to 35 °C) or at a higher temperature of max. 40 °C. The

temperature of the column shall not change by more than 1 °C during the analysis (see Annex C).

5.6 Detector

Use a differential refractometer detector. The cell volume shall not exceed 0,010 ml.

NOTE For the restriction to a single detector type, see Annex C.

If copolymer samples or polymer blends are analysed, ensure that all the components give a similar

response factor (ratio of detector signal to concentration of analyte in the eluate or, in the case of

the differential refractometer, specific refractive index increment dn/dc), i.e. the relationship of the

response factors k and k for components i and j respectively is as follows:
i j
02, ≤≤5 (3)

If the ratio of the response factors does not fall within this range in the analysis of a set of samples,

a different detector or
...

SLOVENSKI STANDARD
oSIST prEN ISO 13885-1:2021
01-maj-2021
Gelska permeacijska kromatografija (GPC) - 1. del: Tetrahidrofuran (THF) kot
izpiralna tekočina (eluent) (ISO 13885-1:2020)

Gel permeation chromatography (GPC) - Part 1: Tetrahydrofuran (THF) as eluent (ISO

13885-1:2020)

Gelpermeationschromatographie (GPC) - Teil 1: Tetrahydrofuran (THF) als Elutionsmittel

(ISO 13885-1:2020)

Chromatographie par perméation de gel (GPC) - Partie 1: Utilisation de tétrahydrofurane

(THF) comme éluant (ISO 13885-1:2020)
Ta slovenski standard je istoveten z: prEN ISO 13885-1
ICS:
87.060.20 Veziva Binders
oSIST prEN ISO 13885-1:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 13885-1:2021
---------------------- Page: 2 ----------------------
oSIST prEN ISO 13885-1:2021
INTERNATIONAL ISO
STANDARD 13885-1
Third edition
2020-07
Gel permeation chromatography
(GPC) —
Part 1:
Tetrahydrofuran (THF) as eluent
Chromatographie par perméation de gel (GPC) —
Partie 1: Utilisation de tétrahydrofurane (THF) comme éluant
Reference number
ISO 13885-1:2020(E)
ISO 2020
---------------------- Page: 3 ----------------------
oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

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 2020 – All rights reserved
---------------------- Page: 4 ----------------------
oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 2

5 Apparatus ..................................................................................................................................................................................................................... 2

5.1 Eluent supply ............................................................................................................................................................................................ 2

5.2 Pump ................................................................................................................................................................................................................ 3

5.3 Injection system ..................................................................................................................................................................................... 3

5.4 Separation columns ............................................................................................................................................................................ 3

5.5 Column temperature control ...................................................................................................................................................... 5

5.6 Detector ......................................................................................................................................................................................................... 5

6 Reagents ........................................................................................................................................................................................................................ 5

7 Calibration of the apparatus .................................................................................................................................................................... 6

7.1 General ........................................................................................................................................................................................................... 6

7.2 Requirements for the calibration standards ................................................................................................................. 6

7.3 Preparation of the calibration solutions for injection ........................................................................................... 7

7.4 Conditions for calibration runs ................................................................................................................................................. 7

7.5 Measurement of elution volume .............................................................................................................................................. 7

7.6 Plotting the calibration curve ..................................................................................................................................................... 7

8 Sampling ........................................................................................................................................................................................................................ 8

9 Preparation for the test ................................................................................................................................................................................. 8

9.1 Preparation of the injection solution ................................................................................................................................... 8

9.2 Preparation of the apparatus ...................................................................................................................................................... 9

10 Analytical parameters ..................................................................................................................................................................................... 9

11 Data acquisition and evaluation ........................................................................................................................................................... 9

11.1 General ........................................................................................................................................................................................................... 9

11.2 Calculation of the net chromatogram from the raw data ................................................................................10

11.2.1 Determination of the baseline ...........................................................................................................................10

11.2.2 Correction of the measured values and of the net chromatogram ....................................10

11.2.3 Evaluation limits ...........................................................................................................................................................10

11.3 Calculation of the average values .........................................................................................................................................10

11.4 Calculation of the distribution curves ..............................................................................................................................11

12 Precision ....................................................................................................................................................................................................................12

12.1 General ........................................................................................................................................................................................................12

12.2 Repeatability ..........................................................................................................................................................................................12

12.3 Reproducibility ....................................................................................................................................................................................12

13 Test report ................................................................................................................................................................................................................13

13.1 General ........................................................................................................................................................................................................13

13.2 General data on the equipment and settings .............................................................................................................13

13.2.1 Data on the equipment used ...............................................................................................................................13

13.2.2 Calibration ..........................................................................................................................................................................13

13.2.3 Evaluation ...........................................................................................................................................................................14

13.3 Special data on the sample ........................................................................................................................................................14

Annex A (informative) Conversion of experimental parameters for variant column sizes ......................16

Annex B (informative) Example of a data sheet for a polymer standard .....................................................................17

Annex C (informative) Explanations ..................................................................................................................................................................18

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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)

Bibliography .............................................................................................................................................................................................................................23

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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(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 35, Paints and varnishes.

This third edition cancels and replaces the second edition (ISO 13885-1:2008), which has been

technically revised. The main changes compared to the previous edition are as follows:

— this document has been adapted to the actual state of the art, especially with regards to software

engineering;
— the scope has been revised;
— the definition for gel-permeation chromatography has been revised;
— the text has been revised editorially.
A list of all parts in the ISO 13885 series can be found on the ISO website.

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.
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oSIST prEN ISO 13885-1:2021
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oSIST prEN ISO 13885-1:2021
INTERNATIONAL STANDARD ISO 13885-1:2020(E)
Gel permeation chromatography (GPC) —
Part 1:
Tetrahydrofuran (THF) as eluent

WARNING — This document can involve hazardous materials, operations or equipment. It

does not purport to address all of the safety problems, 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 national regulatory conditions.
1 Scope

This document specifies the determination of the molar-mass distribution and the average molar mass

values M (number average) and M (weight average) of polymers that are soluble in tetrahydrofuran

n w
(THF) by gel permeation chromatography (GPC).
NOTE Also known as size exclusion chromatography (SEC).

Even though the chromatograms obtained show good repeatability, it is possible that this method

cannot be used with certain polymer types because of specific interactions (e.g. adsorption) within the

sample/eluent/column system.

The conditions specified in this document are not applicable to the GPC analysis of polymer samples

with M values greater than 10 g/mol and/or of polymers with elution limits outside the calibration

range (see 7.6 and Annex C).

This document includes no correction method (e.g. for the elimination of peak broadening. If absolute

molar-mass values are required, an absolute method (e.g. membrane osmometry for M or light

scattering for M ) can be used.
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 1513, Paints and varnishes — Examination and preparation of test samples
ISO 4618, Paints and varnishes — Terms and definitions

ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 4618 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)
3.1
gel permeation chromatography
GPC

separation of molecules, mainly based on exclusion effects such as differences in the size and/or shape

of molecules (size exclusion chromatography) or in charge (ion exclusion chromatography)

3.2
system peak

signal peculiar to the gel permeation chromatography (3.1) using a refractive index detector

Note 1 to entry: These signals appear at the total penetration limit of the columns and are not part of the sample,

but of the overall system.
4 Principle

The dissolved (molecularly disperse) molecules of a polymer sample are fractionated on a porous

column material, with separation taking place according to the size of the molecule (or, more precisely,

the polymer coil size which forms in this eluent). Small molecules diffuse into the pores of the column

material more frequently and are therefore retarded more than large molecules. Thus, large molecules

are eluted earlier, small molecules later. Under the test conditions given, the elution volume is solely a

function of the coil size of the molecule.

The polymer content of a sample is determined, the sample is then diluted with eluent to give a

concentration of less than 5 g/l and an aliquot of the diluted sample is injected into the GPC system. The

concentration of the molecules eluted from the column is measured in order of decreasing coil size with

a concentration-sensitive detector (typically a differential refractometer). With the aid of a calibration

curve that has been determined for the particular GPC system, the relative molar-mass distribution, the

relative quantities M and M and the heterogeneity or polydispersity M /M are calculated from the

n w w n
chromatogram obtained.
5 Apparatus

The apparatus shall consist of the components shown in Figure 1, which are described below.

All the components which come into contact with the eluent or the sample solution shall be resistant

and shall not exhibit adsorption or memory effects in any form. The individual components of the GPC

apparatus, which in this case uses THF as eluent, shall be connected to capillary tubes made of high-

quality steel or titanium.
Figure 1 — Block diagram of a GPC apparatus
5.1 Eluent supply

The eluent reservoir shall adequately protect the eluent against external influences such as the

atmosphere and light, if necessary by means of a blanket of inert gas above the liquid level.

The eluent reservoir shall contain a sufficient quantity of the eluent to bring the apparatus to

equilibrium and to carry out several repeat analyses.
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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)

The eluent shall be degassed, either before it is introduced into the reservoir or by use of a device fitted

between the reservoir and the pump, to prevent malfunctions of the pump or the formation of bubbles

in the detector. The method of degassing used (e.g. bubble trap, online purging with helium, or vacuum

degassing) is open to choice.
5.2 Pump

The pump shall ensure that the eluent flow through the separation column is as smooth and pulse free

as possible. The flow rate shall be 1 ml/min (see Annex A). To fulfil these requirements, the pump shall

operate at optimum efficiency at this flow rate.
The flow rate of the pump used shall have a variation of max. 0,1 %.
5.3 Injection system

The injection system serves to introduce a given amount of the sample solution into the eluent stream

in a rapid and smooth fashion. This introduction may be carried out either manually or automatically.

If the introduction is carried out manually, ensure that the sample loop is filled completely with solvent

before loading with the sample.

Memory effects from the previous sample solution in the injection system shall be avoided by adequate

flushing.
5.4 Separation columns

The apparatus shall have one or more columns connected in series and packed with spherical porous

material, the diameter of the pores corresponding to the size of the polymer molecules being analysed.

The packing material typically consists of a styrene/divinylbenzene copolymer (S/DVB), produced by

a special polymerization process, which swells only slightly in the solvent and therefore cannot deform

under the pressure developed at the set flow rate.

In addition to these macroporous spherical S/DVB particles, packing materials based on other organic

monomers or on silicon dioxide (silica) are also used. The criterion for their use is that no adsorptive

interaction shall occur between their surface and the polymer molecules in the sample. Furthermore,

the sample being analysed shall not be changed, either chemically or structurally, within the

chromatographic system.

Certain polymers interact with the surface of the packing material (e.g. by adsorption) and other effects

can sometimes interfere with the GPC separation mechanism. Details of such effects and notes on

possible remedies are discussed in Annex C. If it is intended to compare analyses of such polymers by

different laboratories, the laboratories shall agree on details of the test conditions that are not covered

by this document.

For good repeatability of test results, it is necessary to adhere to the minimum requirements specified

below with regard to peak broadening (expressed in terms of a number of theoretical plates) and

separation efficiency.
a) Number of theoretical plates

The number of theoretical plates, N, shall be determined, for the apparatus used per metre of

column used, from the peak width at half height (see Figure 2). Inject up to 20 µl of ethylbenzene

(mass concentration 1 g/l) on to the column (see Annex A) and evaluate the chromatogram obtained

under the same conditions as are used for analysing polymers, using Formula (1):
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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)
 
100
N =×55, 4   × (1)
 
1/2
 
where
V is the elution volume at the peak maximum;

W is the peak width at half height (see Figure 2); the same units shall be used for V and W ;

1/2 e 1/2
L is the length of the column (column combination), in centimetres.

Express as the result the number of theoretical plates per metre of column length. To conform to the

requirements of this document, the column combination shall have at least 20 000 theoretical plates

per metre.

NOTE See Annex C for tailing and fronting (asymmetry) of the peak used to calculate the plate count.

Key
X elution volume
Y peak intensity
1 injection
V elution volume at the peak maximum
W peak width at the half maximum height of the peak
1/2
h maximum peak height
σ standard deviation

Figure 2 — Determination of the number of theoretical plates by the half-height method

b) Separation efficiency

To ensure adequate resolution, the log M versus the elution volume, V , calibration curve for the

10 e

column combination used shall not exceed a specified gradient. For the purposes of this document,

the relation given in Formula (2) shall apply to the area of the peak maximum for the polymer

sample under investigation:
VV−
e,M e, 10×M
x x
>60, (2)
where
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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)
V is the elution volume for polystyrene of molar mass M , in cubic centimetres;
e,M
V is the elution volume for 10 times that molar mass, in cubic centimetres;
e,10×M
A is the cross-sectional area of the column, in square centimetres.

M is the molar mass, that shall be selected such that the peak maximum for the poly-

mer sample under investigation lies in approximately halfway between these two
elution volumes.
5.5 Column temperature control

Carry out the test at room temperature (15 °C to 35 °C) or at a higher temperature of max. 40 °C. The

temperature of the column shall not change by more than 1 °C during the analysis (see Annex C).

5.6 Detector

Use a differential refractometer detector. The cell volume shall not exceed 0,010 ml.

NOTE For the restriction to a single detector type, see Annex C.

If copolymer samples or polymer blends are analysed, ensure that all the components give a similar

response factor (ratio of detector signal to concentration of analyte in the eluate or, in the case of

the differential refractometer, specific refractive index increment dn/dc), i.e. the relationship of the

response factors k and k for components i and j respectively is as follows:
i j
02, ≤≤5 (3)

If the ratio of the response factors does not fall within this range in the analysis of a set of samples,

a different detector or suitable combination of detectors may be used. If it is intended to compare

the results obtained by different laboratories for such a set of samples, the type of detector shall be

agreed upon. If a different detector is used, the reasons for using it shall be stated in the test report. See

Annex C.

The detector response obtained using the injection amounts specified in this document shall, at the

lowest setting for electronic damping, exhibit a noise level of less than 1 % of the maximum height of

the polymer peak. As the noise level is influenced by variations in pressure, temperature and flow rate,

particularly in the differential refractometer, suitable measures are to be taken to maintain a constant

temperature and to damp out pulses.

The signals from the detector are recorded by means of an electronic data system (see Clause 11 for

details).
6 Reagents
The eluent shall consist of THF with the following specification:
THF >99,5 % (mass fraction)
Water <0,05 % (mass fraction)
Peroxide <0,005 % (mass fraction)

THF may be stabilized with 2,6-di-tert-butyl-4-methylphenol (BHT) (up to a maximum of 0,250 g/l) to

prevent the formation of peroxides.

The peroxide content of THF shall be checked before use (e.g. using test strips).

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oSIST prEN ISO 13885-1:2021
ISO 13885-1:2020(E)

In exceptional cases, which shall be explained in the test report, it may be necessary to incorporate

further components in the THF eluent, up to a maximum of 10 g/l, to avoid interference with the

analysis of certain samples (see Annex C for details).

Discard the eluent used to condition the columns or to perform the analyses, and do not return it to the

eluent reservoir.
7 Calibration of the apparatus
7.1 General

The method is not an absolute one and requires calibration with commercially available unbranched

polystyrene standards that have been characterized by independent absolute methods. The results for

samples of polymers with different chemical structures are therefore only comparable within groups of

samples of the same type.

Calibrate the GPC apparatus with a series of unbranched polystyrene standards of narrow molar mass

distribution (see Annex C) and whose molar masses have been determined by independent, absolute

methods. The result is a calibration curve for the evaluation of GPC analyses of polystyrene samples.

If this calibration curve is used to analyse samples of other compositions, containing molecules with

[3]

other structures, the results shall be expressed as the “polystyrene molar mass equivalent” .

7.2 Requirements for the calibration standards

The molar-mass distribution of the standards shall be narrower than the limits given below as a

function of the molar mass at the peak maximum, M :
M < 2 000 g/mol M /M ≤ 1,2
p w n
2 000 g/mol ≤ M < 10 g/mol M /M ≤ 1,05
p w n
10 g/mol ≤ M M /M ≤ 1,2
p w n

The empirical peak-asymmetry factor for each chromatogram, calculated from the peak widths A and

B at half height before and after the perpendicular through the peak maximum, shall lie in the range

given by Formula (4).
=±10,,00 15 (4)

The widths A and B shall be determined from electronically acquired data on peaks defined by at least

60 measuring points.

The following minimum requirements shall be fulfilled in the characterization of each individual

polystyrene standard used for calibration:

a) at least one average molar mass value, M , M or M , shall be determined by an absolute method;

n w z
b) at least one method shall be used to determine the molar-mass distribution;
c) all the parameters involved in the method used shall be indicated;

d) the results and data for each batch analysed shall be presented in a comprehensible form for the user.

NOTE An example of a data sheet is given in Annex B.

If the calibration standards give a shoulder on either side of the peak, pre-peaks or a tailing peak, the

area represented by these anomalies shall be less than 2,0 % of the peak area, otherwise the calibr

...

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