SIST EN 60450:2005

SLOVENSKI SIST EN 60450:2005
STANDARD
januar 2005
Merjenje povprečne viskozimetrične stopnje polimerizacije novih in staranih
celuloznih elektroizolacijskih materialov (IEC 60450:2004)
(istoveten EN 60450:2004)
Measurement of the average viscometric degree of polymerization of new and aged
cellulosic electrically insulating materials (IEC 60450:2004)
ICS 29.035.01 Referenčna številka
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

EUROPEAN STANDARD EN 60450
NORME EUROPÉENNE
EUROPÄISCHE NORM June 2004
ICS 17.220.99; 29.035.01
English version
Measurement of the average viscometric degree of polymerization
of new and aged cellulosic electrically insulating materials
(IEC 60450:2004)
Mesure du degré de polymérisation Messung des durchschnittlichen
moyen viscométrique des matériaux viskosimetrischen Polymerisationsgrades
isolants cellulosiques neufs et vieillis von neuen und gealterten
à usage électrique cellulosehaltigen Elektroisolierstoffen
(CEI 60450:2004) (IEC 60450:2004)

This European Standard was approved by CENELEC on 2004-06-01. CENELEC 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 Central Secretariat or to any CENELEC 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 CENELEC member into its own language and
notified to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2004 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 60450:2004 E
Foreword
The text of document 15E/229/FDIS, future edition 2 of IEC 60450, prepared by SC 15E, Methods of
test, of IEC TC 15, Insulating materials, was submitted to the IEC-CENELEC parallel vote and was
approved by CENELEC as EN 60450 on 2004-06-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2005-03-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2007-06-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60450:2004 was approved by CENELEC as a European
Standard without any modification.
__________
- 3 - EN 60450:2004
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following referenced documents are indispensable for the application 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.
NOTE Where an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
1) 2)
IEC 60814 - Insulating liquids - Oil-impregnated paper EN 60814 1997
and pressboard - Determination of water
by automatic coulometric Karl Fischer
titration
1)
ISO 287 - Paper and board - Determination of - -
moisture content - Oven-drying method

1)
ISO 3105 - Glass capillary kinematic viscometers - - -
Specification and operating instructions

1)
Undated reference.
2)
Valid edition at date of issue.

NORME CEI
INTERNATIONALE
IEC
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
2004-04
Mesure du degré de polymérisation moyen
viscosimétrique des matériaux isolants
cellulosiques neufs et vieillis à usage électrique

Measurement of the average viscometric degree
of polymerization of new and aged cellulosic
electrically insulating materials

 IEC 2004 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
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Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
CODE PRIX
S
PRICE CODE
Commission Electrotechnique Internationale
International Electrotechnical Commission
Международная Электротехническая Комиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue

60450  IEC:2004 – 3 –
CONTENTS
FOREWORD.5
INTRODUCTION.9

1 Scope.11
2 Normative references.11
3 Terms, definitions and symbols .11
3.1 Terms and definitions .11
3.2 Symbols.13
4 Principle.15
5 Apparatus and reagents.15
6 Specimens.17
6.1 Preparation of specimens.17
7 Experimental procedure.19
7.1 Measurement of water content of paper.19
7.2 Determination of viscosity.19
8 Test report.31

Annex A (normative) Cuen solution.33
Annex B (normative) Preparation of Cuen solution.35
c
En
Annex C (normative) Procedure for the verification of the ratio of the Cuen solution.41
c
Cu
.
Annex D (informative) Numerical values of the product [v] c as a function of v
s
according to Martin's formula .43

Bibliography.45

Table 1 – Symbols .13
Table 2 – DP values of specimen .19
v
.
Table D.1 – [ν] c as a function of ν (k = 0,14). .43
s
Figure 1 – Chemical structure of cellulose .11
Figure 2 – Ubbelohde viscometer tube.27

60450  IEC:2004 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
–––––––––––
MEASUREMENT OF THE AVERAGE VISCOMETRIC DEGREE OF
POLYMERIZATION OF NEW AND AGED CELLULOSIC ELECTRICALLY
INSULATING MATERIALS
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60450 has been prepared by subcommittee 15E: Methods of test,
of IEC technical committee 15: Insulating materials.
This second edition cancels and replaces the first edition, published in 1974, and constitutes
a technical revision. Experience has indicated the need for improved description of the
experimental method. It describes a revised procedure that overcomes the limitations of the
first edition.
The text of this standard is based on the following documents:
FDIS Report on voting
15E/229/FDIS 15E/235/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.

60450  IEC:2004 – 7 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.
The committee has decided that this publication remains valid until 2008. At this date, in
accordance with the committee’s decision, the publication will be
 reconfirmed;
 withdrawn;
 replaced by a revised edition, or
 amended.
60450  IEC:2004 – 9 –
INTRODUCTION
Experience has indicated the need for an improved description of the experimental method for
the reproducible determination of the average viscometric degree of polymerization of new
and aged cellulosic electrically insulating material.
The major error appears to arise from oxidative degradation occurring during processing and
effluxing. Other significant factors include the need to ensure that all of the material is
dissolved and used, as well as the effect of the speed of effluxing.

60450  IEC:2004 – 11 –
MEASUREMENT OF THE AVERAGE VISCOMETRIC DEGREE OF
POLYMERIZATION OF NEW AND AGED CELLULOSIC ELECTRICALLY
INSULATING MATERIALS
1 Scope
This International standard describes a standardized method for the determination of the
average viscometric degree of polymerization ( DP ) of new and aged cellulosic electrically
ν
insulating materials. It may be applied to all cellulosic insulating materials such as those used
in transformer, cable or capacitor manufacturing.
The methods described can also be used for the determination of the intrinsic viscosity of
solutions of chemically modified kraft papers, provided that these dissolve completely in the
selected solvent.
Caution should be taken if the method is applied to loaded kraft papers.
NOTE Within a sample of material, all the cellulose molecules do not have the same degree of polymerization so
that the mean value measured by viscometric methods is not necessarily the same as that which may be obtained
by, for instance, osmotic or ultra centrifuging methods.
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 60814, Insulating liquids – Oil-impregnated paper and pressboard – Determination of
water by automatic coulometric Karl Fischer titration
ISO 287, Paper and board – Determination of moisture content – Oven-drying method
ISO 3105, Glass capillary kinematic viscometers – Specifications and operating instructions
3 Terms, definitions and symbols
For the purposes of this document, the following terms, definitions and symbols apply.
3.1 Terms and definitions
3.1.1
degree of polymerization of a cellulose molecule
number of anhydrous-β-glucose monomers, C H O , in the cellulose molecule
6 10 5
NOTE Figure 1 shows the chemical structure of cellulose.
CH OH
CH OH
OH
O O
HO
HO
O
O
HO
HO
OH
O
OH
OH
CH OH
n – 2
IEC  424/04
Figure 1 – Chemical structure of cellulose

60450  IEC:2004 – 13 –
3.1.2
Cuen
1 mol/l aqueous solution of bis(ethylenediamine)copper(II) hydroxide
Cu(H NCH CH NH ) (OH) . [CAS 14552-35-3]
2 2 2 2 2 2
NOTE In some countries the abbreviation CED is used for bis(ethylenediamine)copper(II) hydroxide.

3.1.3
paper
cellulosic electrically insulating material, such as paper, presspaper, pressboard and
components made thereof
NOTE In the present document such paper is termed “paper”.
3.2 Symbols
Symbols used in this standard are shown in Table 1.
Table 1 – Symbols
Symbol Definition
Mark Houwink constant of the cellulose monomer
α
c Molarity of copper in Cuen solution

Cu
Molarity of ethylenediamine in Cuen solution
c
En
Constants for viscometer tubes 0, 1 and 2 respectively
C , C and C
0 1 2
c Concentration of solution
Average viscometric degree of polymerization
DP
ν
Kinematic viscosity of solution
ν
v Kinematic viscosity of solvent
K Mark Houwink characteristic constant of the polymer/solvent system
k Constant in Martin's formula
m Mass of dry paper
D
Mass of swollen paper in tared vessel
m
T
Mass of added water
m
H O
Density of water
ρ
H O
v Volume of added water
H O
Volume of added Cuen
v
Cu
Intrinsic viscosity
[ν]
v Specific viscosity
s
Efflux time for tests A and B on dissolved specimen 1
t t
,
1A 1B
Efflux time for tests A and B on dissolved specimen 2
t , t
2A 2B
t t Efflux time for tests A and B on pure solvent
,
0A 0B
t Efflux time for diluted Cuen solvent (50 % Cuen and 50 % water)
t Efflux time for Cuen dissolved specimen
S
———————
Chemical Abstracts Service (CAS) Registry numbers®

60450  IEC:2004 – 15 –
4 Principle
The specific viscosity ν of a solution of the paper in Cuen is determined. From this result the
s
intrinsic viscosity [ν] of the solution is deduced, and from this the degree of polymerization is
calculated.
NOTE Solutions of cellulose are non-Newtonian fluids. Their viscosity decreases as the flow velocity increases
(sometimes known as “structural viscosity”). Although the viscosity of dilute solutions varies only slightly with the
gradient of the velocity modulus, the use of conditions outside those specified in this standard may result in
unacceptable errors.
Specific viscosity ν is defined by
s
viscosity of paper solution − viscosity of solvent
ν = (1)
s
viscosity of solvent
Intrinsic viscosity [ν] is defined by
ν
 
s
νlim (2)
=
 
c→0 c
 
where c is the concentration of the solution.
The average viscometric degree of polymerization DP (the ratio of the mean molecular mass
ν
indicated viscometrically to the molecular mass of the monomeric unit) is related to the
intrinsic viscosity [ν] by the equation:
α
[ν] = K ⋅ DP (3)
ν
K and α being characteristic Mark Houwink coefficients of the polymer-solvent system
(paper/Cuen) and of the monomer respectively.
v
The intrinsic viscosity [ν] is calculated from the specific viscosity and the concentration c
s
by Martin’s empirical formula:
� ⋅[]ν�
ν = [ν] ⋅ c ⋅10 (4)
s
where k is Martin’s constant. For kraft papers k = 0,14.
5 Apparatus and reagents
NOTE 1 Apparatus and reagents for the preparation of Cuen are given separately in Annexes A and B.
During the analysis, unless otherwise specified, use only reagents of recognized analytical
grade and only distilled /de-ionized water or equivalent quality.
A glass fronted, thermostatically controlled bath, suitable for the immersion of the viscometer
tubes, capable of maintaining a temperature of 20 °C to within ±0,1 K and fitted with
appropriate means for illuminating the tubes. It shall be fitted with a means of displaying the
temperature to within an accuracy of ±0,05 K.
NOTE 2 To obtain the required degree of temperature stability, it may be necessary to use a refrigeration unit in
addition to the bath heater.
60450  IEC:2004 – 17 –
Calibrated capillary type viscometer tubes according to ISO 3105 with a capillary constant of
0,005 or 0,01. Non calibrated tubes can be used as long as the viscosities of the Cuen solvent
and solution of paper in Cuen are measured in the same tube.
A timer/stopwatch capable of measuring to within an accuracy of ±0,1 s.
Suitable blender or grinder to “activate” the paper sample to allow dissolution.
Suitable vials (typically 25 ml to 50 ml) with lids (not paper) that make an effective seal for the
preparation of paper/Cuen solution. Alternative glass containers can be used. However, these
shall be sealed during dissolution to minimize oxidative degradation of the Cuen.
Cuen (see Annex A).
Distilled or de-ionized water.
Low oxygen content nitrogen supply (minimum 99,9 % nitrogen).
Acetone minimum 99,0 % pure.
Pentane or hexane minimum 99,0 % .
20 % aqueous nitric acid.
Vented drying oven thermostatically controlled to 105 °C ± 2 K.
Analytical balance capable of weighing 20 g to within ±0,1 mg.
Soxhlet extractor.
Pipette to deliver ±0,1 ml.
Mechanical shaker capable of holding the glass vials used to prepare the paper/Cuen
solutions or a magnetic stirrer can be used to dissolve the paper/Cuen solution.
6 Specimens
6.1 Preparation of specimens
The paper under evaluation shall only be handled with gloves or forceps. It shall not be
touched by hand.
Pressboard with a thickness greater than 1 mm, shall be split into layers of less than 1 mm.
The samples shall be cut into pieces sufficiently small to facilitate the subsequent processes.
For very thin paper, the material may be cut into small pieces using scissors.

60450  IEC:2004 – 19 –
6.1.1 Impregnated papers
Impregnated papers shall be degreased before weighing and absorbing solution.
Wash a sufficient amount of the pape
...