EN ISO 175:2010

Plastics - Methods of test for the determination of the effects of immersion in liquid chemicals (ISO 175:2010)

ISO 175:2010 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 the various parts of ISO 22088.
It only considers testing by immersion of the entire surface of the test specimen.
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.

Kunststoffe - Prüfverfahren zur Bestimmung des Verhaltens gegen flüssige Chemikalien (ISO 175:2010)

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
Spannungsrissbildung, die in den unterschiedlichen Teilen der ISO 22088 beschrieben wird.
1.2 Diese Norm berücksichtigt nur die Prüfung durch Eintauchen der gesamten Oberfläche des
Probekörpers.0F
1) 31H1F
ANMERKUNG Zur Veranschaulichung einer nur teilweisen oder selten auftretenden Feuchtigkeitseinwirkung auf
Kunststoffe ist dieses Verfahren möglicherweise ungeeignet.
1.3 Die vorliegende Norm ist auf alle festen Kunststoffe anwendbar, die aus Form- oder
Strangpressmaterialien bestehen oder in Form von Platten, Rohren, Stäben oder Folien vorliegen und dicker
als 0,1 mm sind. Auf Schaumstoffmaterialien ist sie nicht anwendbar.

Plastiques - Méthodes d'essai pour la détermination des effets de l'immersion dans des produits chimiques liquides (ISO 175:2010)

L'ISO 175:2010 spécifie une méthode d'exposition d'éprouvettes en plastique exemptes de toute contrainte extérieure à des produits chimiques liquides, ainsi que des méthodes de détermination des variations des caractéristiques résultant d'une telle exposition. Elle ne concerne pas la fissuration sous contrainte dans un environnement donné (ESC) qui est traitée dans les différentes parties de l'ISO 22088.
Elle n'envisage que l'essai par immersion sur toute la surface de l'éprouvette.
Elle est applicable à tous les plastiques compacts se présentant sous forme de matières à mouler ou à extruder, de plaques, tubes, joncs ou feuilles ayant une épaisseur supérieure à 0,1 mm. Elle n'est pas applicable aux matériaux alvéolaires.

Polimerni materiali - Preskusne metode za ugotavljanje učinkov pri potapljanju v tekoče kemikalije (ISO 175:2010)

Ta mednarodni standard določa metodo izpostavljanja preskusnih vzorcev polimernih materialov brez zunanjih omejitev tekočim kemikalijam in metode za določevanje sprememb v lastnostih zaradi takega potapljanja. Ne zajema razpokanja zaradi okoljskih vplivov (ESC), ki ga obravnavajo različni deli ISO 22088. Obravnava le preskušanje s potapljanjem celotne površine preskušanca.

General Information

• Status: Published
• Publication Date: 14-Oct-2010
• Withdrawal Date: 29-Apr-2011
• ICS: 83.080.01 - Plastics in general
• ICS: 83.080.10 - Thermosetting materials
• Technical Committee: CEN/TC 249 - Plastics
• Drafting Committee: CEN/TC 249 - Plastics
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 15-Oct-2010
• Completion Date: 15-Oct-2010
• Ref Project: SIST EN ISO 175:2011 - Plastics - Methods of test for the determination of the effects of immersion in liquid chemicals (ISO 175:2010)

Relations

• Replaces: EN ISO 175:2000 - Plastics - Methods of test for the determination of the effects of immersion in liquid chemicals (ISO 175:1999)
• Effective Date: 24-Oct-2009

Overview - EN ISO 175:2010 (Plastics - Immersion in Liquid Chemicals)

EN ISO 175:2010 / ISO 175:2010 specifies standardized test methods for exposing plastic test specimens, free from external restraint, to liquid chemicals and for determining the resulting changes in properties. The standard covers complete immersion of the entire specimen surface and applies to solid plastics available as mouldings, extrusions, plates, sheets, rods or tubes with thickness > 0.1 mm. It excludes cellular materials and does not address environmental stress cracking (ESC).

Key topics and technical requirements

• Scope & applicability: Tests apply to solid plastics (>0.1 mm) and full-surface immersion only; ESC covered by ISO 22088.
• Test liquids: Use analytical-grade or representative technical liquids; single-batch sourcing recommended for reproducibility.
• Specimen condition: Specimens must be free from external restraint, conditioned per standard atmospheres (see ISO 291), and prepared by moulding or machining (ISO 294-3, ISO 2818).
• Immersion parameters: Control of immersion time, temperature, and liquid composition is essential. Tests can be tailored to simulate service conditions.
• Measurements: Determine changes in mass, dimensions, colour/appearance, and other physical properties (mechanical, thermal, optical) before immersion, immediately after removal, and after drying where applicable.
• Absorption: Procedures for quantifying absorbed liquid and distinguishing reversible (swelling) vs irreversible changes (chemical reaction or extraction of constituents).
• Procedure & reporting: Requirements for apparatus, testing sequence, expression of results, precision, and comprehensive test reporting.

Practical applications and who uses this standard

EN ISO 175:2010 is used for:

• Material selection & specification - compare chemical resistance of candidate plastics.
• Quality control & incoming inspection - confirm batch-to-batch behavior in contact with chemicals.
• R&D and formulation - evaluate effects of solvents, fuels, lubricants or process chemicals on new polymers and additives.
• Failure analysis & lifetime assessment - investigate property changes after liquid exposure.
• Typical users: materials engineers, polymer scientists, testing laboratories, product designers in automotive, chemical processing, piping, packaging, electrical insulation and consumer goods sectors, and regulatory/compliance teams.

Related standards

• ISO 22088 (environmental stress cracking)
• ISO 62 (water absorption)
• ISO 291 (conditioning atmospheres)
• ISO 294-3, ISO 2818 (specimen preparation)
• ISO 3126, ISO 4582 (dimensional and appearance testing)
• IEC 60296 (insulating fluids)

EN ISO 175:2010 provides a reproducible, comparative method for assessing how plastics respond to liquid chemicals - a core tool for ensuring material performance and reliability in chemical exposure environments.

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2011
1DGRPHãþD
SIST EN ISO 175:2000
3ROLPHUQLPDWHULDOL3UHVNXVQHPHWRGH]DXJRWDYOMDQMHXþLQNRYSULSRWDSOMDQMXY
WHNRþHNHPLNDOLMH,62
Plastics - Methods of test for the determination of the effects of immersion in liquid
chemicals (ISO 175:2010)
Kunststoffe - Prüfverfahren zur Bestimmung des Verhaltens gegen flüssige Chemikalien
(ISO 175:2010)
Plastiques - Méthodes d'essai pour la détermination des effets de l'immersion dans des
produits chimiques liquides (ISO 175:2010)
Ta slovenski standard je istoveten z: EN ISO 175:2010
ICS:
83.080.01 Polimerni materiali na Plastics in general
splošno
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 175
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2010
ICS 83.080.01 Supersedes EN ISO 175:2000
English Version
Plastics - Methods of test for the determination of the effects of
immersion in liquid chemicals (ISO 175:2010)
Plastiques - Méthodes d'essai pour la détermination des Kunststoffe - Prüfverfahren zur Bestimmung des Verhaltens
effets de l'immersion dans des produits chimiques liquides gegen flüssige Chemikalien (ISO 175:2010)
(ISO 175:2010)
This European Standard was approved by CEN on 14 October 2010.

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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 175:2010: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
This document (EN ISO 175:2010) has been prepared by Technical Committee ISO/TC 61 "Plastics" in
collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by April 2011, and conflicting national standards shall be withdrawn at the
latest by April 2011.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 175:2000.
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, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 175:2010 has been approved by CEN as a EN ISO 175:2010 without any modification.

INTERNATIONAL ISO
STANDARD 175
Third edition
2010-10-15
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

Reference number
ISO 175:2010(E)
©
ISO 2010
ISO 175:2010(E)
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ii © ISO 2010 – All rights reserved

ISO 175:2010(E)
Contents Page
Foreword .iv
Introduction.v
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 .2
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, dimensions and appearance .6
5.1 General .6
5.2 Apparatus.6
5.3 Test specimens.7
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.12
6 Determination of changes in other physical properties.13
6.1 General .13
6.2 Apparatus.13
6.3 Test specimens.13
6.4 Procedure.13
6.5 Calculation and expression of results .14
7 Precision .14
8 Test report.15
Annex A (normative) Types of test liquid.16
Annex B (informative) Notes on the absorption of moisture by plastic specimens in equilibrium
with a conditioning atmosphere .19
Bibliography.20

ISO 175:2010(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 175 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 6, Ageing, chemical
and environmental resistance.
This third edition cancels and replaces the second edition (ISO 175:1999), of which it constitutes a minor
revision.
iv © ISO 2010 – All rights reserved

ISO 175:2010(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.

INTERNATIONAL STANDARD ISO 175:2010(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 the various
parts of ISO 22088.
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 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.
ISO 291:2008, Plastics — Standard atmospheres for conditioning and testing
ISO 294-3, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 3: Small plates
ISO 2818, Plastics — Preparation of test specimens by machining
ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions
ISO 4582, Plastics — Determination of changes in colour and variations in properties after exposure to
daylight under glass, natural weathering or laboratory light sources
IEC 60296, Fluids for electrotechnical applications — Unused mineral insulating oils for transformers and
switchgear
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.
ISO 175:2010(E)
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.
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.
4.2 Test conditions
4.2.1 Test temperatures
The preferred test temperatures are:
a) (23± 2) °C;
b) (70± 2) °C.
2 © ISO 2010 – All rights reserved

ISO 175:2010(E)
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 one of the following temperatures:
−269 °C; −196 °C; −161 °C; −70 °C; −55 °C; −40 °C; −25 °C; −10 °C; 0 °C; 5 °C; 25 °C; 40 °C; 55 °C;
70 °C; 85 °C; 100 °C; 105 °C; 125 °C; 150 °C; 175 °C; 200 °C; 225 °C; 250 °C; 275 °C; 300 °C; 350 °C;
400 °C; 450 °C; 500 °C; 600 °C; 700 °C; 800 °C; 900 °C; 1 000 °C
NOTE These temperatures originate from ISO 3205:1976.
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 3205:1976 may be used.
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.
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:
d) 1 h — 2 h — 4 h — 8 h — 16 h — 24 h — 48 h — 96 h — 168 h;
e) 2 weeks — 4 weeks — 8 weeks — 16 weeks — 26 weeks — 52 weeks — 78 weeks;
f) 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.
ISO 175:2010(E)
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.
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 can 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 291:2008.
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 can 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 might, 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.
4 © ISO 2010 – All rights reserved

ISO 175:2010(E)
If light is likely to affect the action of the test liquid, it is recommended that the test be 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.
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 could be a simple visual
examination, a 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 (X ), using the following formula:
X
×100
X
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
0,5
immersion times t as the abscissae. If it is necessary to shorten the immersion-time scale, either a t
...