Rubber, vulcanized — Determination of the effect of liquids

Caoutchouc vulcanisé — Détermination de l'action des liquides

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Status
Withdrawn
Publication Date
03-Mar-1999
Withdrawal Date
03-Mar-1999
Current Stage
9599 - Withdrawal of International Standard
Completion Date
25-Oct-2005
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ISO 1817:1999 - Rubber, vulcanized -- Determination of the effect of liquids
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INTERNATIONAL ISO
STANDARD 1817
Third edition
1999-03-01
Rubber, vulcanized — Determination of the
effect of liquids
Caoutchouc, vulcanisé — Détermination de l’action des liquides
A
Reference number
ISO 1817:1999(E)

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ISO 1817:1999(E)
Contents
1 Scope .1
2 Normative references .1
3 Apparatus .2
4 Test liquids.3
5 Test pieces .4
5.1 Preparation.4
5.2 Dimensions.4
5.3 Time interval between vulcanization and testing .4
5.4 Conditioning.4
6 Immersion in the test liquid .5
6.1 Temperature .5
6.2 Duration .5
7 Procedure .5
7.1 General.5
7.2 Change in mass .6
7.3 Change in volume.6
7.4 Change in dimensions .7
7.5 Change in surface area .8
7.6 Change in hardness.8
7.7 Change in tensile stress-strain properties.9
7.8 Test with liquid on one surface only.9
7.9 Determination of extractable matter .10
8 Test report .10
Annex A (normative) Reference liquids .12
©  ISO 1999
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic
or mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet iso@iso.ch
Printed in Switzerland
ii

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© ISO
ISO 1817:1999(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.
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.
International Standard ISO 1817 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products,
Subcommittee SC 2, Physical and degradation tests.
This third edition cancels and replaces the second edition (ISO 1817:1985), of which it constitutes a technical
revision.
Annex A forms an integral part of this International Standard.
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© ISO
ISO 1817:1999(E)
Introduction
The action of a liquid on vulcanized rubber may generally result in
a) absorption of the liquid by the rubber;
b) extraction of soluble constituents from the rubber;
c) a chemical reaction with the rubber.
The amount of absorption [a)] is usually larger than that of extraction [b)] so that the net result is an increase in
volume, commonly termed “swelling”. The absorption of liquid can profoundly alter physical and chemical properties
and hence change tensile strength, extensibility and hardness of the rubber, so it is important to measure these
properties after treatment of the rubber. The extraction of soluble constituents, especially plasticizers and
antidegradants, can likewise alter the rubber's physical properties and chemical resistance after drying (assuming
the liquid to be volatile). Therefore, it is necessary to test these properties following immersion or drying of the
rubber. This International Standard describes the methods necessary for determining the changes in the following
properties:
 change in mass, volume and dimensions;
 extractable matter;
 change in hardness and tensile stress-strain properties after immersion and after immersion and drying.
Although in some respects these tests may simulate service conditions, no direct correlation with service behaviour
is implied. Thus, the rubber giving the lowest change in volume is not necessarily the best one in service. The
thickness of the rubber must be taken into account since the rate of penetration of liquid is time-dependent and the
bulk of a very thick rubber product may remain unaffected for the whole of the projected service life, especially with
viscous liquids. Moreover, it is known that the action of a liquid on rubber, especially at high temperatures, can be
affected by the presence of atmospheric oxygen. The tests described in this International Standard can, however,
provide valuable information on the suitability of a rubber for use with a given liquid and, in particular, constitute a
useful control when used for developing rubbers resistant to oils, fuels, or other service liquids.
The effect of a liquid may depend on the nature and magnitude of any stress within the rubber. In this International
Standard, test pieces are tested in an unstressed condition.
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INTERNATIONAL STANDARD  © ISO ISO 1817:1999(E)
Rubber, vulcanized — Determination of the effect of liquids
WARNING — Persons using this International Standard should be familiar with normal laboratory practice.
This standard 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 International Standard describes methods of evaluating the resistance of vulcanized thermoset or
thermoplastic rubbers to the action of liquids by measurement of properties of the rubbers before and after
immersion in test liquids. The liquids concerned include current service liquids, such as petroleum derivatives,
organic solvents and chemical reagents as well as reference test liquids.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this
International Standard. At the time of publication, the editions indicated were valid. All standards are subject to
revision, and parties to agreements based on this International Standard are encouraged to investigate the
possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain
registers of currently valid International Standards.
ISO 37:1994, Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties.
ISO 48:1994, Rubber, vulcanized or thermoplastic — Determination of hardness (hardness between 10 IRHD and
100 IRHD).
1)
ISO 175:— , Plastics — Methods of test for the determination of the effects of immersion in liquid chemicals.
ISO 471:1995, Rubber — Temperatures, humidities and times for conditioning and testing.
2)
ISO 2592:— , Petroleum products — Determination of flash and fire points — Cleveland open cup method.
ISO 2977:1997, Petroleum products and hydrocarbon solvents — Determination of aniline point and mixed aniline
point.
ISO 3016:1994, Petroleum products — Determination of pour point.
ISO 3104:1994, Petroleum products — Transparent and opaque liquids — Determination of kinematic viscosity and
calculation of dynamic viscosity.

1) To be published. (Revision of ISO 175:1981)
2) To be published. (Revision of ISO 2592:1973)
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© ISO
ISO 1817:1999(E)
ISO 3675:1998,
Crude petroleum and liquid petroleum products — Laboratory determination of density —
Hydrometer method.
ISO 4661-1:1993, Rubber, vulcanized or thermoplastic — Preparation of samples and test pieces — Part 1:
Physical tests.
ISO 5661:1983, Petroleum products — Hydrocarbon liquids — Determination of refractive index.
3 Apparatus
3.1  Total immersion apparatus, designed to take account of the volatility of the test liquid and of the immersion
temperature in order to prevent and minimize evaporation of the test liquid and the ingress of air.
For tests at temperatures considerably below the boiling point of the test liquid, a stoppered glass bottle or tube
shall be used. For tests at temperatures near the boiling point of the test liquid, the bottle or tube shall be fitted with
a reflux condenser or other suitable means of minimizing the evaporation of liquid.
The bottle or tube shall be so dimensioned that the test pieces remain completely immersed and freely exposed on
all surfaces without restraint. The volume of liquid shall be at least 15 times the combined volume of the test pieces
and the volume of air above the liquid shall be kept to a minimum.
The test pieces shall be mounted in jigs, preferably hanging on a rod or wire, and separated from any adjacent test
piece, for instance by glass rings or other non-reactive spacers.
The materials of the apparatus shall be inert to the test liquid and to the rubber; for example materials containing
copper shall not be used.
3.2  Apparatus for testing one surface only, which holds the test piece in contact with the liquid on only one of
its surfaces.
A suitable apparatus is illustrated in figure 1. It comprises a base-plate (A) and an open-ended cylindrical chamber
(B), which is held tightly against the test piece (C) by wing nuts (D) mounted on bolts (E). A hole of approximately
30 mm diameter is allowed in the base-plate for examination of the surface not in contact with the liquid. During the
test, the opening on the top of the chamber shall be closed by a close-fitting plug (F).
3.3  Balance, accurate to 1 mg.
3.4  Instrument for measuring the thickness of the test piece, consisting of a micrometer dial-gauge, of
adequate accuracy, firmly held in a rigid stand over a flat base-plate.
The gauge shall have a scale graduated in divisions of 0,01 mm. The plunger shall be fitted with a flat circular
2
contact having a surface area of approximately 100 mm . The contact shall be perpendicular to the plunger and
parallel to the base-plate. The dial-gauge shall operate to give a pressure on the rubber of approximately 2 kPa.
3.5  Instrument for measuring the length and width of the test piece, having a scale graduated in divisions of
0,01 mm and preferably operating without contact with the test piece, for example using an optical system.
3.6  Instrument for measuring the change in surface area, capable of measuring the lengths of the diagonals of
the test pieces.
It shall have a scale graduated in divisions of 0,01 mm and preferably operates without contact with the test piece,
for example using an optical system.
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© ISO
ISO 1817:1999(E)
Dimensions in millimetres
Figure 1 — Apparatus for testing one surface only
4 Test liquids
The choice of the test liquid shall depend on the purpose of the test.
When information is required on the service behaviour of a vulcanized rubber in contact with a particular liquid, then
this liquid shall, if possible, be chosen for the test. Commercial liquids are not always constant in composition and
the test shall, whenever practicable, include a reference material of known characteristics. Any abnormal results
due to unexpected variations in the composition of the commercial liquid will thus become apparent. It may be
necessary to set aside a bulk supply of the liquid for a particular series of tests.
Mineral oils and fuels are liable to vary considerably in chemical composition even when supplied at a recognized
specification. The aniline point of a mineral oil gives some indication of its aromatic content and helps to
characterize the action of the oil on rubber, but the aniline point alone is not sufficient to characterize a mineral oil;
other things being equal, the lower the aniline point, the more pronounced the action. If a mineral oil is used as test
liquid, the test report shall include the density, refractive index, viscosity and aniline point or aromatic content of the
oil. For the reference mineral oils described in annex A, mineral oil raffinates are employed.
Service oils having similar fluid characteristics to the reference liquids (see annex A, clauses A.1 to A.3) will not
necessarily have the same effect on the material as the reference liquids. Some fuels, particularly gasoline, vary
widely in composition and, for some possible constituents, minor variations can have a large influence on the effect
on rubber. Complete details of the composition of the fuel used shall therefore be included in the test report.
As commercial liquids do not always have a constant composition, a standard liquid consisting of well-defined
chemical compounds or mixtures of compounds shall be used as reference liquid for the purpose of classification of
vulcanized rubbers or quality control. Some suitable liquids are recommended in annex A.
When testing to determine the effect of chemical solutions, the concentration of the solution shall be appropriate to
the intended use.
Ensure that the composition of the test liquid does not change significantly during immersion. The ageing of the test
liquid and any interaction with the test pieces shall be taken into consideration. If there are chemically active
additives in the liquid, or if there is a significant change in composition by extraction, absorption or reaction with the
rubber, either the volume shall be increased, or the liquid shall be replaced with fresh liquid at specified intervals.
3

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© ISO
ISO 1817:1999(E)
5 Test pieces
5.1 Preparation
Test pieces shall be prepared in accordance with ISO 4661-1.
5.2 Dimensions
Data obtained on test pieces having different original thicknesses may not be comparable. Therefore, where
possible, test pieces shall be of uniform thickness of (2 – 0,2) mm.
Test pieces cut from commercial articles may be used. For products thinner than 1,8 mm, use the original thickness.
If the material is thicker than 2,2 mm, reduce the thickness to (2 – 0,2) mm.
3 3
Test pieces for the determination of the change in volume and mass shall have a volume of 1 cm to 3 cm .
Test pieces for the determination of the change in hardness shall have lateral dimensions of no less than 8 mm.
Test pieces for the determination of the change in dimensions shall be quadrilateral with sides between 25 mm and
50 mm, or circular with a diameter of 44,6 mm (internal diameter of type B test piece in ISO 37). This type of test
piece can also be used for the determination of mass and volume.
Test pieces for the determination of the change in surface area shall be rhomboid, with the sides cut cleanly and at
right angles to the top and bottom surfaces. This can be achieved by two consecutive cuts at approximately right
angles to each other, with a cutter consisting of two parallel blades, suitably spaced. The length of the sides shall be
nominally 8 mm.
NOTE For the determination of the change in surface area, it may be convenient to use smaller or thinner test pieces, for
example when cut from products or when rapid attainment of equilibrium is required. However, the results may not be
comparable with those obtained using the specified thickness. Smaller test pieces will reduce the precision of the results.
Test pieces for the determination of tensile properties shall be in accordance with ISO 37, preferably type 2 dumb-
bells. This type of test piece can also be used when determining the changes in mass, volume or hardness.
For tests with liquid contact on one surface only, the test piece shall consist of a disc with a diameter of about
60 mm.
5.3 Time interval between vulcanization and testing
Unless otherwise specified for technical reasons, the following requirements, in accordance with ISO 471 for time
intervals, shall be observed.
For all test purposes, the minimum time between vulcanization and testing shall be 16 h.
For non-product tests, the maximum time between vulcanization and testing shall be 4 weeks and, for evaluations
intended to be comparable, the tests shall be carried out using, as far as possible, the same time interval.
For product tests, whenever possible, the time between vulcanization and testing shall not exceed 3 months. In
other cases, tests shall be made within 2 months of the date of receipt of the product by the customer.
5.4 Conditioning
Test pieces for test in the “as received” condition shall be conditioned for not less than 3 h at one of the standard
laboratory temperatures specified in ISO 471. The same temperature shall be used throughout any test or any
series of tests intended to be comparable.
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© ISO
ISO 1817:1999(E)
6 Immersion in the test liquid
6.1 Temperature
The immersion shall preferably be carried out at one or more of the temperatures listed in 4.3.2 of ISO 471:1995.
As elevated temperatures may greatly increase the oxidation of the rubber, volatilization or decomposition of the
immersion liquid and the effect of any chemically active additives in the liquid (for example in service liquids),
appropriate selection of the test temperatures is very important.
In tests intended to simulate service conditions, and using the actual liquid with which the rubber will be used, the
test conditions shall approximate those found in service, using the closest standard temperature equal to or higher
than the service temperature.
6.2 Duration
Since the rate of penetration of liquids into rubbers depends on the temperature, the type of rubber material and the
type of liquid, the use of only one standard period of immersion is precluded. For acceptance purposes, it is
recommended that repeated determinations be made and recorded after subsequent periods of immersion so as to
indicate the change in properties with time. The total immersion time shall, if possible, extend well beyond the point
of maximum absorption.
For control purposes, a single period of immersion may suffice but maximum absorption should preferably be
reached. For such purposes one of the following periods shall be used:
0 0
24h72h
−2 −2
7 days – 2 h Multiples of 7 days – 2 h.
NOTE 1 Since the amount of liquid absorbed is initially proportional to the square root of time rather than time itself, it is
helpful to assess the “time to maximum absorption” by plotting the amount absor
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