SIST EN ISO 175:2000
(Main)Plastics - Methods of test for the determination of the effects of immersion in liquid chemicals (ISO 175:1999)
Plastics - Methods of test for the determination of the effects of immersion in liquid chemicals (ISO 175:1999)
Migrated from Progress Sheet (TC Comment) (2000-07-10): DIS already initiated--> we will submit the revision of ISO 175:1981 when pu- ++ blished to the UAP procedure (TA/980625)
Kunststoffe - Prüfverfahren zur Bestimmung des Verhaltens gegen flüssige Chemikalien (ISO 175:1999)
Diese Internationale Norm legt ein Verfahren zur Lagerung von Probekörpern aus Kunststoffen ohne äußere Beanspruchungen in flüssigen Chemikalien fest sowie Verfahren zur Bestimmung der Änderungen von Eigenschaften, die sich aus dieser Lagerung ergeben. Nicht erfaßt wird die umweltbedingte Spannungs- rißbildung, die in ISO 4599, ISO 4600 und ISO 6252 beschrieben wird.
Plastiques - Méthodes d'essai pour la détermination des effets de l'immersion dans des produits chimiques liquides (ISO 175:1999)
Polimerni materiali - Preskusne metode za ugotavljanje učinkov pri potapljanju v tekoče kemikalije (ISO 175:1999)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 175:2000
01-december-2000
3ROLPHUQLPDWHULDOL3UHVNXVQHPHWRGH]DXJRWDYOMDQMHXþLQNRYSULSRWDSOMDQMXY
WHNRþHNHPLNDOLMH ,62
Plastics - Methods of test for the determination of the effects of immersion in liquid
chemicals (ISO 175:1999)
Kunststoffe - Prüfverfahren zur Bestimmung des Verhaltens gegen flüssige Chemikalien
(ISO 175:1999)
Plastiques - Méthodes d'essai pour la détermination des effets de l'immersion dans des
produits chimiques liquides (ISO 175:1999)
Ta slovenski standard je istoveten z: EN ISO 175:2000
ICS:
83.080.01 Polimerni materiali na Plastics in general
splošno
SIST EN ISO 175:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 175:2000
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SIST EN ISO 175:2000
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SIST EN ISO 175:2000
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SIST EN ISO 175:2000
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SIST EN ISO 175:2000
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SIST EN ISO 175:2000
INTERNATIONAL ISO
STANDARD 175
Second edition
1999-05-01
Plastics — Methods of test for the
determination of the effects of immersion in
liquid chemicals
Plastiques — Méthodes d'essai pour la détermination des effets de
l'immersion dans des produits chimiques liquides
A
Reference number
ISO 175:1999(E)
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SIST EN ISO 175:2000
ISO 175:1999(E)
Contents
1 Scope .1
2 Normative references .1
3 Principle.2
4 General requirements and procedure.2
4.1 Test liquids.2
4.2 Test conditions .3
4.3 Immersion time .3
4.4 Test specimens.3
4.5 Conditioning.4
4.6 Procedure .4
4.7 Expression of results .5
5 Determination of changes in mass and/or dimensions and/or appearance.5
5.1 General.5
5.2 Apparatus .6
5.3 Test specimens (see also 4.4) .6
5.4 Determination of changes in mass .8
5.5 Determination of changes in dimensions .10
5.6 Determination of changes in colour or other appearance attributes .11
6 Determination of changes in other physical properties .12
6.1 General.12
6.2 Apparatus .12
6.3 Test specimens.12
6.4 Procedure .13
© 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
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SIST EN ISO 175:2000
© ISO
ISO 175:1999(E)
6.5 Calculation and expression of results. 13
7 Precision. 14
8 Test report . 14
Annex A (normative) Types of test liquid . 15
Annex B (informative) Notes on the absorption of moisture by plastic specimens in equilibrium
with a conditioning atmosphere . 18
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SIST EN ISO 175:2000
© ISO
ISO 175:1999(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
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 175 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 6,
Ageing, chemical and environmental resistance.
This second edition cancels and replaces the first edition (ISO 175:1981), which has been technically revised.
Annex A forms a normative part of this International Standard. Annex B is for information only.
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SIST EN ISO 175:2000
© ISO
ISO 175:1999(E)
Introduction
Because of their varied applications, plastics are frequently brought into contact with liquids such as chemical
products, motor fuels, lubricants, etc., and, possibly, with their vapours.
Under the action of a liquid, a plastic material may be subjected to several phenomena which may occur
simultaneously. On the one hand, absorption of liquid and extraction of constituents soluble in the liquid may occur.
On the other hand, a chemical reaction, often resulting in a significant change in the properties of the plastic, may
occur. The equilibrium swelling ratio for a crosslinked polymer in a liquid that is a solvent for the same but non-
crosslinked polymer is a measure of the degree of crosslinking.
The behaviour of plastics in the presence of liquids can be determined only under arbitrarily fixed conditions aimed
at making comparisons between different materials. The choice of test conditions (nature of the liquid, immersion
temperature and immersion time), as well as the choice of the properties in which changes are to be measured,
depends on the eventual application of the plastic under test.
It is not possible, however, to establish any direct correlation between the experimental results and the behaviour of
the plastic in service. These tests do, nevertheless, permit a comparison to be made of the behaviour of different
plastic materials under specified conditions, thus allowing an initial evaluation of their behaviour in relation to certain
groups of liquids.
NOTE In view of its special importance, the particular case of the determination of the quantity of water absorbed is dealt
with in ISO 62. ISO 175 is concerned with the effects of water only where changes in the dimensions and physical properties of
the plastic occur as a result of the action of the water.
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SIST EN ISO 175:2000
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SIST EN ISO 175:2000
INTERNATIONAL STANDARD © ISO ISO 175:1999(E)
Plastics — Methods of test for the determination of the effects of
immersion in liquid chemicals
1 Scope
1.1 This International Standard specifies a method of exposing test specimens of plastic materials, free from all
external restraint, to liquid chemicals, and methods for determining the changes in properties resulting from such
immersion. It does not cover environmental stress cracking (ESC) which is dealt with by ISO 4599, ISO 4600 and
ISO 6252.
1)
1.2 It only considers testing by immersion of the entire surface of the test specimen.
NOTE This method may not be appropriate for simulating partial or infrequent wetting of plastics.
1.3 It is applicable to all solid plastics that are available in the form of moulding or extrusion materials, plates,
tubes, rods or sheets having a thickness greater than 0,1 mm. It is not applicable to cellular materials.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 62:1999, Plastics — Determination of water absorption.
ISO 291:1997, Plastics — Standard atmospheres for conditioning and testing.
ISO 293:1986, Plastics — Compression moulding test specimens of thermoplastic materials.
ISO 294-3:1996, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 3: Small plates.
ISO 295:1991, Plastics — Compression moulding of test specimens of thermosetting materials.
ISO 1817:1999, Rubber, vulcanized — Determination of the effect of liquids.
ISO 2818:1994,
Plastics — Preparation of test specimens by machining.
ISO 3126:1974, Plastics pipes — Measurement of dimensions.
ISO 3205:1976, Preferred test temperatures.
1) Although it is not within the scope of this International Standard, it may also be of interest, when dealing with volatile liquids
or those which give off vapours, to subject the specimen to only the gaseous phase above the liquid. In this event, it is
advisable to proceed exactly as indicated, but to suspend the specimen above the liquid, seal the container and maintain it at
the test temperature throughout.
1
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SIST EN ISO 175:2000
© ISO
ISO 175:1999(E)
ISO 4582:1998, —
Plastics Determination of changes in colour and variations in properties after exposure to
daylight under glass, natural weathering or laboratory light sources.
IEC 60296:1992, Specification for unused mineral insulating oils for transformers and switchgear.
3 Principle
Test specimens are completely immersed in a test liquid for a specified time and at a specified temperature.
Their properties are determined before immersion and after removal from the liquid, as well as after drying, if
applicable. In the last-mentioned case, the determinations are made, if possible, one after the other on the same
specimens.
NOTE The comparison of different plastics by means of this test is valid only if the specimens used are of the same shape,
of the same dimensions (in particular of the same thickness) and in as nearly as possible the same state (of internal stress,
surface, etc.).
Methods are specified for determining the following:
a) changes in mass, dimensions and appearance immediately after removal from the liquid and after removal and
drying;
b) changes in physical properties (mechanical, thermal, optical, etc.) immediately after removal from the liquid and
after removal and drying;
c) the amount of liquid absorbed.
Measurements are made immediately after removal when it is necessary to ascertain the state of the material while
it is still being acted on by the liquid. Measurements are made after removal and drying when it is necessary to
ascertain the state of the material after the liquid, provided it is volatile, has been eliminated. It also allows the
influence of a soluble constituent to be determined.
4 General requirements and procedure
4.1 Test liquids
4.1.1 Choice of test liquid
If information is required about the behaviour of a plastic in contact with a specific liquid, that liquid shall be used.
The test liquid shall be of analytical quality.
Industrial liquid chemicals are not generally of absolutely constant composition. The tests shall be carried out using
defined chemical products, either on their own or as a mixture, which are as representative as possible of the
products under consideration in their effect on the plastic material concerned. When technical-grade chemicals are
used, they shall be of agreed origin and quality, and care shall be taken that only one manufacturing batch is used
for all measurements in any one series.
NOTE If conducting a series of tests in a liquid of doubtful composition, it is important to take all the samples of the liquid
from the same container.
4.1.2 Types of test liquid
Types of test liquid are given in annex A.
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4.2 Test conditions
4.2.1 Test temperatures
The preferred test temperatures are:
a) 23 °C ± 2 °C;
b) 70 °C ± 2 °C.
If a different temperature has to be used in order to correspond to the temperature at which the plastic is to be used,
it shall be selected from the preferred temperatures given in ISO 3205. The following temperatures are
recommended:
0 °C - 20 °C - 27 °C - 40 °C - 55 °C - 85 °C - 95 °C - 100 °C - 125 °C - 150 °C,
with a tolerance of ± 2 °C on temperatures up to and including 100 °C and ± 3 °C on temperatures greater than
105 °C up to and including 200 °C. In the special case of testing plastic pipes, the temperature of 60 °C given in the
annex to ISO 3205 may be used.
NOTE 1 In the event that the test is to be carried out at a temperature above normal ambient conditions, it may be desirable
to condition another series of specimens at this temperature for a period equal to that of the test, and to measure their
properties after this conditioning in order to be able to distinguish the effect of temperature from that of the liquid.
NOTE 2 In the case of long-duration tests, specimens stored in air at 23 °C may undergo a change in properties. Preparation
of an additional series of test specimens is recommended for comparison purposes.
4.2.2 Measurement temperature
The temperature for the determination of changes in mass, dimensions or physical properties is 23 °C ± 2 °C. If the
immersion temperature is different, bring the specimen to 23 °C by the procedure described in 4.6.3.
4.3 Immersion time
The preferred immersion times are:
a) 24 h for a short-duration test;
b) 1 week for a standard test (particularly at 23 °C);
c) 16 weeks for a long-duration test
If other immersion times need to be used, for example if it is desired to perform tests as a function of time or to plot
the curve until equilibrium is reached, it is recommended that the immersion times be chosen from the following
standard scale:
a) 1 h - 2 h - 4 h - 8 h - 16 h - 24 h - 48 h - 96 h - 168 h;
b) 2 weeks - 4 weeks - 8 weeks - 16 weeks - 26 weeks - 52 weeks - 78 weeks;
c) 1,5 years - 2 years - 3 years - 4 years - 5 years.
4.4 Test specimens
Depending upon the measurements to be made after immersion (mass, dimensions, physical properties) and the
nature and form of the plastic material (sheet, film, rod, etc.), the specimens will be of very diverse shapes and
dimensions.
They may be obtained directly by moulding, or by machining. In the latter case, cut surfaces shall be machined to a
fine finish and shall show no trace of carbonization that could be attributed to the method of preparation.
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For the specimens specified in 5.3.1 and 5.3.2, the preferred specimen size is 60 mm ´ 60 mm with a thickness
depending on the type of plastic material:
for thermoplastics, the preferred thickness is 1,0 mm to 1,1 mm;
for moulding compounds, the specimen is identical to that specified in ISO 294-3;
for semi-finished materials, the specimen should preferably be prepared by machining in accordance with
ISO 2818, leaving at least one original surface intact;
for composites, the preferred thickness is at least 2 mm.
NOTE Tests using specimens thinner or thicker than the recommended 1 mm may be conducted to determine whether
specimen thickness effects changes in mass, dimensions, appearance or amount of liquid absorbed.
The number of specimens to be used will be specified in the International Standards relevant to the tests to be
carried out after treatment. In the absence of specific International Standards, at least three specimens shall be
tested.
4.5 Conditioning
Condition the specimens in atmosphere 23/50, class 2, as defined in ISO 291:1997.
NOTE For certain plastics which are known to approach temperature equilibrium and, in particular, humidity equilibrium
rapidly or very slowly, shorter or longer conditioning periods may be specified in the appropriate product specifications (see
annex B).
4.6 Procedure
4.6.1 Quantity of test liquid
The quantity of test liquid used shall be at least 8 ml per square centimetre of the total surface area of the specimen
in order to avoid too high a concentration of any extracted products in the liquid during the course of the test. The
test liquid shall cover the specimen completely.
NOTE A different quantity of liquid may, however, be specified in particular International Standards; for example, for rigid
PVC and polyolefin pipes, where the amount of extractable substances is known to be very small, a smaller quantity of liquid is
specified in the relevant International Standards.
4.6.2 Positioning of specimens
Place each set of test specimens in a suitable container (see 5.2) and completely immerse them in the test liquid
(using a weight if necessary). When several materials of the same composition are to be tested, it is permissible to
put several sets of specimens in the same container.
Ensure that, for every specimen, only an insignificant proportion of the surface of the specimen makes contact with
the surfaces of other specimens, with the walls of the container or with any weight that is used.
During the test, stir the liquid, for example by swirling it in the container, at least once per day.
If the test lasts longer than seven days, replace the liquid with an equal amount of the original liquid every seventh
day (see note 2 to 4.6.3).
If the liquid is unstable (for example in the case of sodium hypochlorite), replace the liquid more frequently.
NOTE If light is likely to affect the action of the test liquid, it is recommended that the test is carried out either in darkness
or under defined illumination conditions.
It may be necessary in certain cases to specify the height of the liquid level above the specimens (for example if
there is a risk of oxidation) or to measure the volume of the liquid absorbed. The volume absorbed by the specimen
is the difference between the initial volume of the liquid and the volume of the remaining liquid. Where it is
necessary to calculate this, the apparatus shall allow the measurement of the volume of the liquid alone.
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ISO 175:1999(E)
4.6.3 Rinsing and wiping
At the end of the period of immersion, bring the temperature of the specimens back to ambient temperature if
necessary by transferring them quickly into a fresh quantity of test liquid at room temperature and leaving them for a
period of 15 min to 30 min.
Use one of the following procedures for rinsing the specimens after they have been removed from the test liquid:
a) For specimens which have been immersed in acid, alkali or other aqueous solutions, rinse thoroughly with
clean water. Hygroscopic reagents such as concentrated sulfuric acid may remain adsorbed on the surface of
the specimens even after rinsing, requiring immediate special treatment to avoid moisture pickup before and
during weighing.
b) For specimens removed from non-volatile, non-water-soluble organic liquids, rinse with a non-aggressive but
volatile solvent such as light naphtha.
NOTE 1 In the case of specimens immersed in volatile liquids such as acetone or alcohol at ambient temperature, rinsing
and wiping may not be necessary.
Wipe the specimens dry with filter paper or a lint-free cloth.
NOTE 2 It may be necessary to examine the test liquid at the end of the test. This examination may be a simple visual
examination, measurement of the volume or mass of the liquid not absorbed, or a more rigorous examination, including, for
example, a titration.
This examination may not be meaningful if the liquid has been replaced during the test.
4.7 Expression of results
4.7.1 Numerical expression
In addition to giving the measurements made before and after immersion, the value of the property after immersion
(X ) may be expressed (except in special cases of changes in mass) as a percentage of the value before immersion
2
(X ), using the following formula:
1
X
2
·100
X
1
4.7.2 Graphical expression
In every case where measurements are made as a function of time, it is recommended that graphs be plotted. Plot
the values obtained (including the original value), or the differences in value, as the ordinates and the immersion
0,5
times t as the abscissae. If it is necessary to shorten the immersion-time scale, either a t scale or a log t scale
may be used.
The double-logarithmic plot as recommended in ISO 62 of, for example, the mass or volume of liquid absorbed
versus the immersion time allows the determination of the concentration at saturation and the diffusion coefficient
over short immersion times if the absorption follows Fick's law.
5 Determination of changes in mass and/or dimensions and/or appearance
5.1 General
These determinations may, if necessary, be carried out on the same specimens.
At least three specimens shall be used.
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ISO 175:1999(E)
5.2 Apparatus
5.2.1 For all tests
5.2.1.1 Beakers, of suitable dimensions, fitted with lids (airtight, if necessary) and fitted with condensers in the
case of volatile liquids or those which give off vapours. The apparatus shall be resistant to the corrosive effects of
the liquids being used. Beakers that can be tightly sealed shall be used when conducting tests above room
temperature, in order to minimize loss of the liquid by evaporation.
5.2.1.2 Enclosure, thermostatically maintained at the test temperature. Venting shall be provided when tests are
conducted at elevated temperatures with volatile liquids.
5.2.1.3 Thermometer, of suitable range and accuracy.
5.2.1.4 Ventilated oven, if required, capable of being maintained at the chosen drying temperature.
In the absence of any special instructions, use an oven maintained at 50 °C ± 2 °C.
5.2.2 For determinations of changes in mass
5.2.2.1 Weighing bottle.
5.2.2.2 Balance, accurate to within 1 mg for specimens of mass equal to or greater than 1 g, or to within 0,1 mg
for specimens of mass less than 1 g.
5.2.3 For determinations of dimensional changes and changes in volume
5.2.3.1 Dial micrometer, with flat anvils, accurate to 0,01 mm.
5.2.3.2 Calliper gauge, capable of measuring to an accuracy of 0,1 mm.
5.2.3.3 Graduated glass tube, to determine the initial volume of the specimen.
5.2.3.4 Specimen-immersion apparatus, capable of determining the volume of the remaining liquid (see
reference [1] in the bibliography), for example two glass bulbs connected by a graduated capillary and completely
sealed [see Figure 1 a)]. To begin the immersion, the apparatus is turned through 180° so that the specimen in
bulb 1 is immersed in the liquid [see Figure 1 b)]. To determine the volume of liquid remaining, the apparatus is
turned back to its starting position. The liquid flows into bulb 2 and the change in volume of the liquid can be read
from the scale on the capillary [see Figure 1 c)]. After reading the volume, the apparatus is turned back through 180°
and the immersion continued.
5.3 Test specimens (see also 4.4)
5.3.1 Moulding materials
Specimens shall be square with an edge 60 mm ± 1 mm long and a thickness between 1,0 mm and 1,1 mm. They
shall be moulded to shape under the conditions specified in the appropriate product specification (or under the
conditions prescribed by the supplier).
NOTE 1 The general principles for the preparation of moulded specimens are described in ISO 293, ISO 294-3 and ISO 295.
NOTE 2 A square specimen measuring 50 mm ´ 50 mm ´ 4 mm may be used by agreement between the interested parties.
Using this 4-mm-thick specimen will increase the time necessary to reach equilibrium by a factor of sixteen relative to
1-mm-thick specimens.
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ISO 175:1999(E)
Key
1 Bulb 1 3 Liquid
2 Bulb 2 4 Specimen
Figure 1 — Specimen-immersion apparatus
5.3.2 Extrusion compounds
Specimens shall be square with an edge 60 mm ± 1 mm long and a thickness between 1,0 mm and 1,1 mm. They
shall be cut from a sheet of this thickness prepared under the conditions given in the appropriate product
specification (or under the conditions given by the supplier of the material).
NOTE A square specimen measuring 60 mm ´ 60 mm ´ 2 mm may be used by agreement between the interested parties.
5.3.3 Sheets and plates
Specimens shall be square with an edge 60 mm ± 1 mm long and shall be machined in accordance with ISO 2818
from the sheet or plate submitted for test.
If the nominal thickness of the sheet or plate is less than or equal to 25 mm, the thickness of the specimens shall be
the same as that of the sheet or plate.
If the nominal thickness is greater than 25 mm, and in the absence of special provisions in the relevant
specification, the thickness of the specimen shall be reduced to between 1,0 mm and 1,1 mm or between 2,0 mm
and 2,1 mm by machining one face only.
NOTE For Fickian diffusion, the time to reach equilibrium increases in proportion to the square of the specimen thickness.
In particular, 25-mm-thick specimens will typically require more than 5 years to reach equilibrium.
5.3.4 Tubes and rods
5.3.4.1 Tubes
2)
If possible, reference shall be made to the relevant International Standards for the material under test In the
absence of specific International Standards, the specimen shall be a piece of tube of length 60 mm ± 1 mm,
obtained by cutting it at right angles to its longitudinal axis.
2) The preparation of methods of test for plastics pipes is the responsibility of ISO/TC 138, Plastics pipes, fittings and valves
for the transport of fluids. The general procedures described in this International Standard have been used as a basis for the
appropriate methods of evaluating the effects of liquid chemicals on plastic pipes.
ISO 4433,
...
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