《BS-EN-ISO-960-1998.pdf》由会员分享,可在线阅读,更多相关《BS-EN-ISO-960-1998.pdf(20页珍藏版)》请在三一文库上搜索。
1、BRITISH STANDARD BS EN ISO 960:1998 Plastics Polyamides (PA) Determination of water content The European Standard EN ISO 960:1997 has the status of a British Standard ICS 83.080.20 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN ISO 96
2、0:1998 This British Standard, having been prepared under the direction of the Sector Board for Materials and Chemicals, was published under the authority of the Standards Board and comes into effect on 15 October 1998 BSI 05-1999 ISBN 0 580 30425 6 National foreword This British Standard is the Engl
3、ish language version of EN ISO 960:1997. It is identical with ISO 960:1988. The UK participation in its preparation was entrusted to Technical Committee PRI/35, Speciality thermoplastics moulding materials, which has the responsibility to: aid enquirers to understand the text; present to the respons
4、ible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on requ
5、est to its secretary. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement these international or E
6、uropean publications may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a cont
7、ract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN ISO title page, page 2,
8、the ISO title page, page ii, pages 1 to 11 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No.DateComments Licensed Copy:
9、sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN ISO 960:1998 BSI 05-1999i Contents Page National forewordInside front cover Foreword2 Forewordii Text of ISO 9601 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontro
10、lled Copy, (c) BSI ii blank Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 960 November 1997 ICS Descriptors: See ISO document English version Plastics Polyamides (PA) Determination o
11、f water content (ISO 960:1988) Plastiques Polyamides (PA) Dtermination de la teneur en eau (ISO 960:1988) Kunststoffe Polyamide (PA) Bestimmung des Wassergehaltes (ISO 960:1988) This European Standard was approved by CEN on 16 October 1997. CEN members are bound to comply with the CEN/CENELEC Intern
12、al 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 CEN member.
13、 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 Central Secretariat has the same status as the official versions. CEN members ar
14、e the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation
15、 Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1997 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 960:1997 E Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00
16、2006, Uncontrolled Copy, (c) BSI EN ISO 960:1997 BSI 05-1999 2 Foreword The text of the International Standard from Technical Committee ISO/TC 61 “Plastics” of the International Organization for Standardization (ISO) has been taken over as an European Standard by Technical Committee CEN/TC 249 “Plas
17、tics”, the secretariat of which is held by IBN. 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 May 1998, and conflicting national standards shall be withdrawn at the latest by May 1998. According
18、 to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Sp
19、ain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of the International Standard ISO 960:1988 has been approved by CEN as a European Standard without any modification. NOTENormative references to International Standards are listed in Annex ZA (normative). contents Page 1Sco
20、pe1 2Normative references1 3Method A Extraction with anhydrous methanol1 4Method B Extraction by melting under vacuum2 5Method C Extraction by dissolution in a mixture of 3-methylphenol and toluene 3 6Determination of water content by the Karl Fischer method4 7Method D Manometric method5 8Test repor
21、t7 Annex ZA (normative) Normative references to international publications with their relevant European publications11 Figure 1 Automatically filling pipette for method A (extraction with anhydrous methanol)8 Figure 2 Apparatus for determination of water content by method B (vacuum melting)9 Figure
22、3 Apparatus for determination of water content by method D (manometric)10 Table 16 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN
23、ISO 960:1997 ii BSI 04-1999 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 intereste
24、d 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 Com
25、mission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISO Council. They are approved in accordance with ISO procedu
26、res requiring at least 75 % approval by the member bodies voting. International Standard ISO 960 was prepared by Technical Committee ISO/TC 61, Plastics. It cancels and replaces ISO Recommendation R 960:1969, of which it constitutes a technical revision. Descriptors: Plastics, polyamide, chemical an
27、alysis, determination of content, water, test equipment. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 960:1997 BSI 05-19991 1 Scope 1.1 This International Standard specifies methods for the determination of the water content of pol
28、yamides and copolyamides as granules and finished articles. The methods are applicable for the determination of water contents down to 0,01 % (m/m). The water content is of importance in connection with the processing of PA, during which it should have a low value to prevent degradation, and for che
29、cking the moisture content of test specimens and finished articles. 1.2 Four alternative methods are specified in this International Standard. Method A is an extraction method using anhydrous methanol and titration of the water by the Karl Fischer method. It is applicable to granules having a maximu
30、m size of 4 mm 4 mm 3 mm and can be used for all polyamides and copolyamides. Method B is a method of extraction by melting under vacuum and titration of the water by the Karl Fischer method. It may be applied to granules or pieces of mouldings but not to fine powders (particle size less than 400 4m
31、). For low water content (less than 0,1 % (m/m) and precise determination, it is necessary to make a correction for the water of polycondensation1). This method is not recommended when, during the determination, due to a change in molecular mass, additional water is formed or existing water is bound
32、, except when appropriate correction can be made. Method C is a method of extraction by dissolving in a mixture of 3-methylphenol and toluene and titration of the water by the Karl Fischer method. It yields results close to those obtained by method A. It has the advantage of being applicable to gran
33、ules and powders of all sizes and to finished articles with little or no reduction in size. NOTEThe three methods A, B and C differ in the procedure for isolating the water, which is determined in all three cases by the Karl Fischer method. Method D is a manometric method. The water content is deter
34、mined from the pressure increase after evaporation of the water under vacuum. This method cannot be used for polyamides polymerized with strong acids. 1.3 Method C is the reference method. 2 Normative references The following standards contain provisions which, through reference in this text, consti
35、tute 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 t
36、he standards listed below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 760:1978, Determination of water Karl Fischer method (General method). ISO 3146:1985, Plastics Determination of melting behaviour (melting temperature or melting range) of semi-crysta
37、lline polymers. 3 Method A Extraction with anhydrous methanol 3.1 Principle Extraction of a test portion with anhydrous methanol and determination of the extracted water by the Karl Fischer method. 3.2 Reagents During the analysis, use only reagents of recognized analytical grade. 3.2.1 Methanol, an
38、hydrous, having a water content less than 0,1 % (m/m). 3.2.2 Karl Fischer reagent (see 6.2). 3.3 Apparatus Ordinary laboratory apparatus and 3.3.1 Glass flasks, of capacity 250 ml, provided with ground glass or rubber stoppers. 3.3.2 Conical titration flasks, of capacity 150 ml, with standard ground
39、 necks and provided with ground glass stoppers. 3.3.3 Reflux condensers, with ground neck capable of being fitted on to the flasks (3.3.2) and on to the tubes (3.3.4). 3.3.4 Tubes, straight, containing calcium chloride, or other means of drying, with ground joints. 3.3.5 Means for heating the flasks
40、 (3.3.2), electrically, by hot air, or by any other suitable means. 3.3.6 Automatically filling pipettes, of capacity 50 ml (see Figure 1). 3.3.7 Woolf bottles, with two tubes. 3.3.8 Calcium chloride tubes, curved or U-shaped. 3.3.9 Rubber bulb. 1) See KLINE, G.M., Analytical Chemistry of Polymers.
41、Intersc. Pub., Part 1, p. 282 (1958). Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 02:18:50 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 960:1997 2 BSI 05-1999 3.3.10 Pipette, of capacity 10 ml. 3.3.11 Desiccator, containing calcium chloride or another suitable drying agent. 3.3.12 Ba
42、lance, accurate to 0,2 mg. 3.3.13 Apparatus for determining water content by the Karl Fischer method, in accordance with ISO 760. 3.4 Preparation of test sample 3.4.1 Granules Place a representative test sample of approximately 100 g in a perfectly dry glass flask (3.3.1) and immediately close the f
43、lask with either a ground glass or a rubber stopper. NOTEIt is desirable to predry the container in an oven and to cool it above a suitable water absorbent, for example silica gel. 3.4.2 Finished articles Cut or saw the test sample into pieces of a few millimetres dimensions. Proceed quickly to mini
44、mize moisture absorption. Store the test sample as specified in 3.4.1. 3.5 Number of tests Carry out two determinations for each sample. Use test portions of 10 to 15 g, depending on the estimated water content. 3.6 Procedure 3.6.1 Carefully dry the apparatus. 3.6.2 Weigh the test portion to the nea
45、rest 1 mg into a conical titration flask fitted with a ground glass stopper (3.3.2); let m be the mass, in grams, of this test portion. Measure 50 ml of anhydrous methanol (3.2.1) with an automatically filling pipette (3.3.6) and add it to the conical flask containing the test portion. At the same t
46、ime, add 50 ml of anhydrous methanol to another conical flask for a blank test. Stopper the flasks. Keep the stoppered flasks in the desiccator (3.3.11), pending continuation of the test. 3.6.3 Unstopper the flasks and quickly attach them to the reflux condensers (3.3.3) fitted on top with the calci
47、um chloride tubes (3.3.4). Boil the contents of the conical flasks under reflux for 3 h and leave for 45 minutes to cool to room temperature. Separate the flasks from the condensers, quickly stopper them and place them in the desiccator. 3.6.4 Titrate the contents of each flask with the Karl Fischer
48、 reagent as indicated in clause 6. 4 Method B Extraction by melting under vacuum 4.1 Principle Melting of a test portion under vacuum at a temperature approximately 30 C above the melting point of the resin and determination of the amount of water collected by the Karl Fischer method. 4.2 Reagents D
49、uring the analysis, use only reagents of recognized analytical grade. 4.2.1 Methanol, anhydrous, having a water content less than 0,1 % (m/m). 4.2.2 Karl Fischer reagent (see 6.2). 4.3 Apparatus Ordinary laboratory apparatus, and 4.3.1 Vacuum melting unit, capable of maintaining a pressure of less than 500 Pa2). A four-directional unit, given as an example (see Figure 2), comprises the following parts: 4.3.1.1 Heating block, made up of an insulated aluminium cylinder equipped with an electric heating collar having approximat
链接地址:https://www.31doc.com/p-3747981.html