1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 16014-3:2012Plastics Determination ofaverage molecular mass andmolecular mass distribution ofpolymers using size-exclusionchromatographyPart 3: Low-temperature methodBS IS
2、O 16014-3:2012 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 16014-3:2012.It supersedes BS ISO 16014-3:2003 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/21, Testing of plastics.A list of organizations repr
3、esented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580
4、65173 1ICS 83.080.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 July 2012.Amendments issued since publicationDate Text affectedBS ISO 16014-3:2012 ISO 2012P
5、lastics Determination of average molecular mass and molecular mass distribution of polymers using size-exclusion chromatography Part 3: Low-temperature methodPlastiques Dtermination de la masse molculaire moyenne et de la distribution des masses molculaires des polymres par chromatographie dexclusio
6、n strique Partie 3: Mesurage aux basses tempraturesINTERNATIONAL STANDARDISO16014-3Second edition2012-07-01Reference numberISO 16014-3:2012(E)BS ISO 16014-3:2012ISO 16014-3:2012(E)ii ISO 2012 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2012All rights reserved. Unless otherwise specified, no
7、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 either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale
8、56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 16014-3:2012ISO 16014-3:2012(E) ISO 2012 All rights reserved iiiContents PageForeword iv1 Scope 12 Normative references . 13 Terms and definitions . 14 Principle . 15 R
9、eagents 15.1 Eluent 15.2 Reagent for column evaluation . 25.3 Molecular mass standards 25.4 Reagent for flow rate marker (internal standard) . 25.5 Additives 26 Apparatus 26.1 General . 26.2 Eluent reservoir . 26.3 Pumping system 26.4 Injector . 26.5 Columns . 36.6 Detector 36.7 Tubing . 36.8 Temper
10、ature control . 36.9 Recorder and plotter . 36.10 Data-processing system 36.11 Other components 37 Procedure 37.1 Preparation of solutions of molecular mass standards . 37.2 Preparation of sample solutions . 47.3 Preparation of solutions for column performance evaluation 47.4 Setting up the apparatu
11、s . 47.5 Operating parameters 57.6 Number of determinations 58 Data acquisition and processing 59 Expression of results . 510 Precision 610.1 General . 610.2 Experimental conditions . 610.3 Results of round-robin tests 711 Test report . 8Annex A (informative) Further information on applicability of
12、method . 9Annex B (informative) Further information on reagents 10Annex C (informative) Further information on round-robin tests 11Bibliography .17BS ISO 16014-3:2012ISO 16014-3:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bo
13、dies (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 organizatio
14、ns, 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 I
15、SO/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
16、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 16014-3 was prepared by Technical Committee ISO/TC 61, Plastics, Subc
17、ommittee SC 5, Physical-chemical properties.This second edition cancels and replaces the first edition (ISO 16014-3:2003), which has been technically revised. The main changes are as follows:a) the normative references have been updated (see Clause 2);b) Subclause 7.1 (concerning the preparation of
18、solutions of molecular mass standards) has been revised;c) the maximum mass of the polymer sample which may be injected has been reduced from 0,1 mg to 0,05 mg per cubic centimetre of empty column (see 7.5.2);d) Subclause 7.6 (concerning the number of determinations) has been revised;e) further info
19、rmation has been added on the round-robin tests carried out between 1995 and 1998 (see Annex C);f) a bibliography has been added.ISO 16014 consists of the following parts, under the general title Plastics Determination of average molecular mass and molecular mass distribution of polymers using size-
20、exclusion chromatography: Part 1: General principles Part 2: Universal calibration method Part 3: Low-temperature method Part 4: High-temperature method Part 5: Method using light-scattering detectioniv ISO 2012 All rights reservedBS ISO 16014-3:2012INTERNATIONAL STANDARD ISO 16014-3:2012(E)Plastics
21、 Determination of average molecular mass and molecular mass distribution of polymers using size-exclusion chromatography Part 3: Low-temperature method1 ScopeThis part of ISO 16014 specifies a method for determining the average molecular mass and the molecular mass distribution of polymers by size-e
22、xclusion chromatography (SEC) using an organic eluent at a temperature lower than 60 C. The average molecular mass and the molecular mass distribution are calculated from a calibration curve prepared using polymer standards. Therefore, this test method is classified as a relative method (see ISO 160
23、14-1:2012, Annex A).2 Normative referencesThe 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 472,
24、 Plastics VocabularyISO 16014-1:2012, Plastics Determination of average molecular mass and molecular mass distribution of polymers using size-exclusion chromatography Part 1: General principlesISO 16014-2, Plastics Determination of average molecular mass and molecular mass distribution of polymers u
25、sing size-exclusion chromatography Part 2: Universal calibration method3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 472 and in ISO 16014-1 apply.4 PrincipleSee ISO 16014-1:2012, Clause 4.5 Reagents5.1 EluentFor a general discussion of eluents, see
26、ISO 16014-1:2012, 5.1.For examples of eluents used for SEC measurements at temperatures 15 000, and the resolution factor R shall be 1,5 close to the polymer peak. The asymmetry factor shall be within the range 1,00 0,15. The set of columns used should preferably cover the whole range of molecular m
27、asses being determined, and the calibration curve shall be as linear as possible (the correlation factor shall be very close to 1). Determination of the theoretical plate number, the resolution factor and the asymmetry factor of the columns shall be carried out as described in ISO 16014-1:2012, 6.5.
28、The column temperature-control equipment shall be capable of keeping the columns within 0,5 C of the temperature set, to ensure adequate reproducibility of the results.6.6 DetectorSee ISO 16014-1:2012, 6.6.The detector temperature-control equipment shall be capable of keeping the detector within 1 C
29、 of the temperature set, in order to meet the requirements for flow rate and baseline stability (sensitivity). It is recommended that the columns and detector be kept at the same temperature.6.7 TubingSee ISO 16014-1:2012, 6.7.The temperature of the tubing shall be kept constant to ensure that the c
30、olumn performance requirements are met, but it is not necessary to keep the tubing at the same temperature as the column.6.8 Temperature controlOne of the important factors in SEC is that all components need to be kept at a constant temperature. Therefore, an accurate temperature-control system is e
31、ssential to meet the performance requirements for SEC.6.9 Recorder and plotterSee ISO 16014-1:2012, 6.9.6.10 Data-processing systemSee ISO 16014-1:2012, 6.10.6.11 Other componentsIn addition to the components described above, a column guard filter, pressure monitor, pulse damper or related component
32、s may be used, if necessary.7 Procedure7.1 Preparation of solutions of molecular mass standardsThe molecular mass standards used to prepare the calibration curve should preferably be selected so as to cover the range of molecular masses of the polymer being analysed and so that there are at least tw
33、o standards in each molecular mass decade. Solutions may be prepared which contain more than one narrow molecular mass distribution standard, but only when the standards are perfectly separated from each other on the chromatogram. ISO 2012 All rights reserved 3BS ISO 16014-3:2012ISO 16014-3:2012(E)A
34、 solution of mixed molecular mass standards containing standards of high molecular mass ( 1 000 000) might give peaks which are retarded and/or deformed because of the high viscosity of the solution. In such cases, the solutions of high molecular mass standards shall be prepared separately.If molecu
35、lar mass standards having the same chemical structure as the polymer being analysed are not available, the calibration curve may be prepared using standards consisting of a different type of polymer, and a universal calibration curve prepared for this different type of polymer (see ISO 16014-2).If g
36、entle shaking and/or stirring or heating is required to accelerate dissolution, the time shall be as short as possible to avoid any rupture of the polymer chains.Filtration of the solutions is recommended to protect the column from clogging. In such cases, membrane filters or sintered-metal filters
37、with a pore size between 0,2 m and 1 m shall be used. If solid material is observed on the filter, indicating incomplete dissolution, repeat the dissolution process. If a membrane filter is used, the membrane and backing shall be inert to the solvent being used.In general, use solutions within 48 h
38、of preparation. However, longer storage times are allowed if the solution is kept in a cool, dark place to prevent polymer degradation and solvent evaporation.Recommended concentrations for solutions of molecular mass standards are as follows:Mp105have a slow rate of dissolution, however, and it mig
39、ht be necessary to continue beyond 30 min to ensure complete dissolution. Filtration of solutions is recommended to avoid clogging of the column.Sample solution concentrations shall not exceed the following limits:Mw0,3 %, the deviation in Mn 3 % and the deviation in Mw 2 %, the measurements shall b
40、e repeated.8 Data acquisition and processingSee ISO 16014-1:2012, Clause 8.9 Expression of resultsSee ISO 16014-1:2012, Clause 9. ISO 2012 All rights reserved 5BS ISO 16014-3:2012ISO 16014-3:2012(E)10 Precision10.1 GeneralThe precision of this method has been determined in several round-robin tests
41、carried out between 1995 and 1998 in accordance with ISO 5725-1 and ISO 5725-2.10.2 Experimental conditionsThe test samples, which included three types of polystyrene, one type of poly(methyl methacrylate) and one type of polyacrylonitrile, and the calibration standards of narrow molecular mass dist
42、ribution were distributed to the participating laboratories by the organizer. The details of the round-robins were as follows:1st round-robin (1995)Polymer samples (three samples) Polystyrene PS-1Polystyrene PS-2Polystyrene PS-3Calibration 14 polystyrene standardsColumn packing material Polystyrene
43、gelEluent TetrahydrofuranColumn temperature 40 CNumber of laboratories 132nd round-robin (1996) Polymer sample Poly(methyl methacrylate) (PMMA)Calibration 14 polystyrene standardsColumn packing material Polystyrene gelEluent TetrahydrofuranColumn temperature 40 CNumber of laboratories 143rd round-ro
44、bin (1997-1998) Polymer sample Polyacrylonitrile (PAN)Calibration a) 14 polystyrene standardsb) 14 poly(ethylene glycol) and poly(ethylene oxide) standardsColumn packing materials a) Polystyrene gelb) Poly(vinyl alcohol) gelEluent N,N-dimethylformamide (additive: 20 mM of LiBr)6 ISO 2012 All rights
45、reservedBS ISO 16014-3:2012ISO 16014-3:2012(E)Column temperature 40 CNumber of laboratories a) 8 for polystyrene gel columnb) 10 for poly(vinyl alcohol) gel column10.3 Results of round-robin testsThe results, expressed as repeatability and reproducibility, are summarized in Table 1. The raw data are
46、 shown in Annex C.NOTE Both the repeatability and the reproducibility of this method are sufficient for it to be the standard method except when measurements are carried out using non-ideal SEC conditions as shown in the 3rd round-robin using polystyrene gel columns and N,N-dimethylformamide, with 2
47、0 mM of LiBr as additive, as eluent. In this round-robin, large deviations in sRwere caused by interactions between the polystyrene gel column and the polymer sample and/or the standards used for calibration. Therefore this test method cannot be used for polymers that exibit appreciable secondary ef
48、fects, such as adsorption of the polymer molecules on the column packing material or repulsion between the polymer molecules and the packing material.Table 1 Results of round-robin testsPolymerAverage values of Mnand MwaRepeatability, sra%Reproducibility, sRa%Round-robinPS-1Mn= 137 000Mw= 373 0003,1
49、1,38,08,11stPS-2Mn= 70 400Mw= 226 0003,12,15,66,11stPS-3Mn= 38 000Mw= 157 0002,82,46,94,91stPMMAbMn= 163 000Mw= 617 0002,11,79,07,82ndPMMAcMn= 215 000Mw= 834 0002,41,45,78,42ndPANdMn= 202 000Mw= 467 0002,30,728,219,83rdPANeMn= 79 200Mw= 208 0003,21,118,78,23rdPANfMn= 126 000Mw= 418 0002,30,45,85,13rdPANgMn= 77 800Mw= 468 0001,90,76,46,63rdaOutliers were eliminated by Grubbs and Cochrans methods1,3.bCalibration: polystyrene standards.cCalibration: poly(methyl methacrylate) standards.dColumn: polystyrene ge
