1、BRITISH STANDARDBS EN ISO 62:2008Plastics Determination of water absorptionICS 83.080.01g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 62
2、:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 March 2008 BSI 2008ISBN 978 0 580 60709 7National forewordThis British Standard is the UK implementation of EN ISO 62:2008. It supersedes BS EN ISO 62:1999 which is withdrawn.The UK part
3、icipation in its preparation was entrusted to Technical Committee PRI/21, Testing of plastics.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsib
4、le for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since publicationDate CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 62February 2008ICS 83.080.01 Supersedes EN ISO 62:1999 English VersionPlast
5、ics - Determination of water absorption (ISO 62:2008)Plastiques - Dtermination de labsorption deau (ISO62:2008)Kunststoffe - Bestimmung der Wasseraufnahme (ISO62:2008)This European Standard was approved by CEN on 28 January 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulatio
6、ns which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This Europea
7、n Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national
8、 standards bodies of Austria, Belgium, Bulgaria, 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
9、 Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 62:2008: EFore
10、word This document (EN ISO 62:2008) 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
11、 an identical text or by endorsement, at the latest by August 2008, and conflicting national standards shall be withdrawn at the latest by August 2008. 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 b
12、e held responsible for identifying any or all such patent rights. This document supersedes EN ISO 62:1999. 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, Cyp
13、rus, 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 6
14、2:2008 has been approved by CEN as a EN ISO 62:2008 without any modification. BS EN ISO 62:2008ISO 62:2008(E) iiiContents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Principle. 2 4 Apparatus 2 5 Test specimens . 2 5.1 General. 2 5.2 Square-shaped test specimens for homog
15、eneous plastics. 3 5.3 Test specimens of reinforced plastics affected by anisotropic diffusion effects 3 5.4 Tubular test specimens 3 5.5 Rod-shaped test specimens 4 5.6 Specimens cut from finished products, extrusion compounds, sheets or laminates 4 6 Test conditions and procedures . 4 6.1 General.
16、 4 6.2 General conditions . 4 6.3 Method 1: Determination of amount of water absorbed after immersion in water at 23 C 5 6.4 Method 2: Determination of amount of water absorbed after immersion in boiling water . 5 6.5 Method 3: Determination of water-soluble matter lost during immersion 6 6.6 Method
17、 4: Determination of amount of water absorbed after exposure to 50 % relative humidity . 6 7 Expression of results . 6 7.1 Percentage by mass of water absorbed. 6 7.2 Determination of the water content at saturation and the water diffusion coefficient using Ficks laws . 7 8 Precision 8 9 Test report
18、 . 9 Annex A (informative) Correlation between water absorption by test specimens and Ficks diffusion laws 10 Annex B (informative) Precision statement. 12 Bibliography . 15 BS EN ISO 62:2008ISO 62:2008(E) iv Foreword ISO (the International Organization for Standardization) is a worldwide federation
19、 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.
20、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 wit
21、h 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 approv
22、al 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 62 was prepared by Technical Committee I
23、SO/TC 61, Plastics, Subcommittee SC 6, Ageing, chemical and environmental resistance. This third edition cancels and replaces the second edition (ISO 62:1999), to which a precision statement has been added. BS EN ISO 62:2008ISO 62:2008(E) vIntroduction Plastics exposed to water are subject to severa
24、l different effects: a) dimensional changes (e.g. swelling) caused by absorption of water; b) extraction of water-soluble components; c) changes in other properties. However, exposure to humidity, immersion and exposure to boiling water can result in distinctly different material responses. The equi
25、librium moisture content can be used to compare the amount of water absorbed by different types of plastics when they are exposed to moisture. Moisture content determined under non-equilibrium conditions can be used to compare different batches of the same material and to determine the diffusion con
26、stant of the material when determined under carefully controlled non-equilibrium conditions of exposure to moisture and when using plastic specimens of defined dimensions. BS EN ISO 62:2008blank1Plastics Determination of water absorption 1 Scope 1.1 This International Standard describes a procedure
27、for determining the moisture absorption properties in the “through-the-thickness” direction of flat or curved-form solid plastics. This International Standard also describes procedures for determining the amount of water absorbed by plastic specimens of defined dimensions, when immersed in water or
28、when subjected to humid air under controlled conditions. The “through-the-thickness” moisture diffusion coefficient can be determined for single-phase material by assuming Fickian diffusion behaviour with constant moisture absorption properties through the thickness of the test specimen. This model
29、is valid for homogeneous materials and for reinforced polymer-matrix composites tested below their glass transition temperature. However, some two-phase matrices such as hardened epoxies may require a multi-phase absorption model which is not covered by this International Standard. 1.2 Ideally, the
30、best comparison of the water absorption properties and/or diffusion coefficients of materials should be carried out only using the equilibrium moisture content of plastics exposed to identical conditions. The comparison of materials using properties at moisture equilibrium does not assume, and is th
31、erefore not limited to, single-phase Fickian diffusion behaviour. 1.3 Alternatively, water absorption of plastic specimens of defined dimensions exposed to immersion or humidity under controlled conditions but for an arbitrary time period can be used to compare different batches of the same material
32、 or for quality control tests of a given material. For this type of comparison, it is essential that all test specimens be of identical dimensions and, as nearly as possible, have the same physical attributes, e.g. surface smoothness, internal stresses, etc. However, moisture equilibrium is not reac
33、hed under these conditions. Therefore, results from this type of test cannot be used to compare the water absorption properties of different types of plastics. For more reliable results, simultaneous tests are recommended. 1.4 The results obtained using the methods described in this International St
34、andard are applicable to most plastics but are not applicable to cellular plastics, granulates or powders, which can show additional absorption and capillary effects. Plastics exposed to moisture under controlled conditions for defined periods of time provide relative comparisons between them. The t
35、ests described for the determination of the diffusion coefficient may not be applicable to all plastics. Plastics that do not retain their shape when immersed in boiling water should not be compared using method 2 (see 6.4). 2 Normative references The following referenced documents are indispensable
36、 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 175:1999, Plastics Methods of test for the determination of the effects of immersion in liquid ch
37、emicals 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 BS EN ISO 62:2008ISO 62:2008(E) ISO 62:2008(E) 2 3 Principle Test specimens are immersed in distilled water at 23 C or in boi
38、ling distilled water, or exposed to 50 % relative humidity at given temperatures, for prescribed periods. The amount of water absorbed by each test specimen is determined by measuring its change in mass, i.e. the difference between its initial mass and that after exposure to water, the change being
39、expressed as a percentage of the initial mass. If required, the amount of water lost after drying the test specimens can also be determined. In some applications, 70 % to 90 % relative humidity and temperatures of 70 C to 90 C may be necessary. Relative humidities and temperatures higher than those
40、recommended in this International Standard may be used by agreement between the interested parties. When relative humidity and temperature conditions other than those recommended are used, a complete description of these conditions (with appropriate tolerances) shall be included in the test report.
41、4 Apparatus 4.1 Balance, with an accuracy of 0,1 mg (see also 6.1.3). 4.2 Oven, with forced-air convection or vacuum, maintained at (50,0 2,0) C or at any other agreed temperature (see also 6.1.2). 4.3 Containers, containing distilled water or water of equivalent purity, equipped with a means of hea
42、ting capable of maintaining the temperature specified. 4.4 Desiccator, with a desiccant (e.g. P2O5). 4.5 Means of measuring the dimensions of the test specimens to an accuracy of 0,1 mm, if required. 5 Test specimens 5.1 General For each material evaluated, test at least three test specimens. Test s
43、pecimens of the required dimensions may be prepared by moulding or extrusion. The methods used for preparation of all test specimens shall be included in the test report. NOTE The results of this method may be influenced by surface effects. For some materials, different results can be obtained betwe
44、en moulded specimens and specimens cut from a larger sheet. Any contaminant on the test specimen surface which could influence water absorption shall be removed by a cleaning agent which does not attack the plastic, the degree of attack being determined in accordance with ISO 175 for example, the no
45、tation “none” (no change in appearance) in ISO 175:1999, Table 1. Allow specimens to dry at 23 C and 50 % relative humidity for at least 2 h after cleaning and before beginning the test. Wear clean gloves when handling test specimens to prevent contamination. The cleaning agent shall have no effect
46、on the the water absorption. When determining the moisture equilibrium content in accordance with 6.3 (method 1) and 6.6 (method 4), the effects of the cleaning agent can be ignored. BS EN ISO 62:2008ISO 62:2008(E) 35.2 Square-shaped test specimens for homogeneous plastics Unless otherwise specified
47、 or agreed by all interested parties, the dimensions and dimensional tolerances of the square-shaped specimens shall be the same as those given in ISO 294-3, with a thickness of (1,0 0,1) mm. They can be prepared by moulding in accordance with ISO 294-3, using conditions given in standards applicabl
48、e to the material being tested (or using conditions recommended by the material supplier). For some materials, such as polyamides, polycarbonates and some reinforced plastics, use of a 1 mm thick specimen may not give meaningful results. Furthermore, some product specifications require the use of th
49、icker test specimens for the determination of water absorption. In these cases, test specimens of (2,05 0,05) mm thickness may be used. If specimens of thickness other than 1 mm are used, the specimen thickness shall be indicated in the test report. There are no requirements for the radii of the edges and corners. However, they shall be smooth and clean to prevent material from the edges and corners from being lost during the test. Some materials may exhibit mould shrinkage. If specimens of these materials are prepared using a mould with dimensi
