1、 Reference number ISO 7270-1:2003(E) ISO 2003INTERNATIONAL STANDARD ISO 7270-1 First edition 2003-04-15 Rubber Analysis by pyrolytic gas-chromatographic methods Part 1: Identification of polymers (single polymers and polymer blends) Caoutchouc Mthodes danalyse par pyrolyse et chromatographie en phas
2、e gazeuse Partie 1: Identification des polymres (un seul polymre ou un mlange de polymres) ISO 7270-1:2003(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which
3、 are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Inco
4、rporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event th
5、at a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO 2003 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 an
6、d microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii
7、 ISO 2003 All rights reservedISO 7270-1:2003(E) ISO 2003 All rights reserved iiiContents Page Foreword iv 1 Scope 1 2 Normative references . 1 3 Principle . 1 4 Single polymers and blends 2 5 Reagents 3 6 Apparatus. 3 7 Procedure. 4 8 Interpretation of results 5 9 Test report 5 Table 1 List of pyrog
8、rams contained in this part of ISO 7270 6 Table 2 Recommended operating conditions for micro-furnace pyrolysis followed by chromatography with a capillary column 7 Table 3 Recommended operating conditions for Curie-point pyrolysis followed by chromatography with a capillary column 23 Table 4 Recomme
9、nded operating conditions for micro-furnace pyrolysis followed by chromatography with a packed column 36 Table 5 Recommended operating conditions for Curie-point pyrolysis followed by chromatography with a packed column 42 ISO 7270-1:2003(E) iv ISO 2003 All rights reservedForeword ISO (the Internati
10、onal 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
11、 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 standa
12、rdization. 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
13、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
14、such patent rights. ISO 7270 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing and analyses. This part of ISO 7270 cancels and replaces ISO 7270:1987, which has been technically revised. ISO 7270 consists of the following parts, under the general t
15、itle Rubber Analysis by pyrolytic gas- chromatographic methods: Part 1: Identification of polymers (single polymers and polymer blends) Part 2: Determination of styrene/butadiene/isoprene ratio At the time of publication of this part of ISO 7270, Part 2 was in preparation. INTERNATIONAL STANDARD ISO
16、 7270-1:2003(E) ISO 2003 All rights reserved 1Rubber Analysis by pyrolytic gas-chromatographic methods Part 1: Identification of polymers (single polymers and polymer blends) WARNING Persons using this part of ISO 7270 should be familiar with normal laboratory practice. This part of ISO 7270 does no
17、t purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1 Scope This part of ISO 7270 specifies a method for the ident
18、ification of polymers, or blends of polymers, in raw rubbers and in vulcanized or unvulcanized compounds from pyrograms (pyrolysis-gas chromatographic patterns) obtained under the same conditions. This allows qualitative identification of single rubbers or blends, with exceptions discussed below. Th
19、is part of ISO 7270 is not intended for quantitative analysis. The method applies first and foremost to single polymers. When the pyrogram indicates a characteristic hydrocarbon, the method is also applicable to blends. For details, see Clause 4. The method may be also applicable to other types of p
20、olymer, but this must be verified by the analyst in each particular case. NOTE The use of this part of ISO 7270 pre-supposes sufficient working knowledge of the principles and techniques of gas chromatography to enable the analyst to carry out the operations described and to interpret the results co
21、rrectly. 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 1407:1992, Ru
22、bber Determination of solvent extract ISO 1629:1995, Rubber and latices Nomenclature 3 Principle 3.1 Raw or vulcanized rubbers and/or their blends are pyrolysed and the pyrolysis products are subjected to gas-chromatographic analysis under predefined conditions. The chromatograms produced are referr
23、ed to as pyrograms. 3.2 Pyrograms are interpreted by comparison with reference pyrograms produced from the same rubbers and/or blends, prepared and analysed under the same conditions. ISO 7270-1:2003(E) 2 ISO 2003 All rights reserved4 Single polymers and blends 4.1 General The rubbers in the followi
24、ng listing are grouped in accordance with ISO 1629. 4.2 Group M a) Chlorinated polyethylene (CM) and chlorosulfonated polyethylene (CSM). NOTE 1 The pyrogram will not differentiate between these chlorinated polyethylenes. b) Ethylene-propylene copolymers (EPMs) and ethylene-propylene-diene terpolyme
25、rs (EPDMs). NOTE 2 The pyrogram can differentiate terpolymers from copolymers when the pyrogram indicates characteristic “diene” monomer pyrolysis products. c) Acrylic rubbers (ACMs). 4.3 Group O Epichlorohydrin rubbers homopolymer (CO), copolymer (ECO) and terpolymers. NOTE The pyrogram will not di
26、fferentiate betwen these various types of epichlorohydrin polymer. 4.4 Group Q Polysiloxanes. 4.5 Group R a) Polybutadiene (BR). NOTE 1 The pyrogram will not differentiate between polymers containing different proportions of isomers. b) Polychloroprene (CR). NOTE 2 The pyrogram will not differentiat
27、e between the various types of polychloroprene rubber, or polychloroprene rubber from other types of chlorinated rubber. c) Isobutene-isoprene copolymer (IIR). NOTE 3 The pyrogram will not differentiate butyl rubber from its halogenated forms or from isobutene. d) Polyisoprene (NR or IR). NOTE 4 The
28、 pyrogram will not differentiate natural from synthetic polyisoprenes. e) Acrylonitrile-butadiene copolymer (NBR). NOTE 5 In some cases, NBR can be differentiated from hydrogenated acrylonitrile-butadiene copolymer (HNBR). The pyrogram will not differentiate a single NBR from an NBR/BR blend or a bl
29、end of various types of NBR. f) Styrene-butadiene copolymer (SBR). NOTE 6 In some cases, block polymers can be differentiated from random polymers. The pyrogram will not differentiate a single SBR from an SBR/BR blend or a blend of various types of SBR. ISO 7270-1:2003(E) ISO 2003 All rights reserve
30、d 34.6 Blends With the exception of blends containing both styrene-butadiene copolymer and polybutadiene, the method enables blends of the following polymers to be identified: a) polyisoprene (NR or IR); b) polybutadiene (BR); c) isobutene-isoprene copolymers (IIRs); d) styrene-butadiene copolymers
31、(SBRs). 5 Reagents All reagents shall be of analytical grade. 5.1 Solvents for extraction purposes The following solvents are suitable (see 7.2): 5.1.1 Acetone. 5.1.2 Methanol. 5.1.3 Methyl ethyl ketone. 5.2 Carrier gas 5.2.1 Nitrogen. 5.2.2 Helium. 5.3 Gas for flame-ionization detector: hydrogen pl
32、us purified compressed air. 6 Apparatus 6.1 Extraction apparatus As specified in ISO 1407. 6.2 Pyrolysis/chromatography system 6.2.1 General The apparatus utilized to obtain pyrograms consists of four parts: the pyrolysis device, the gas chromatograph, the gas-chromatographic column and the data-han
33、dling equipment. 6.2.2 Pyrolysis device The following types of electrically heated pyrolysis device are suitable: 6.2.1.1 Micro-furnace, with quartz tubes in which the test portion is pyrolysed. ISO 7270-1:2003(E) 4 ISO 2003 All rights reserved6.2.1.2 Curie-point pyrolyser, with a holder (pyrolysis
34、probe) containing ferromagnetic material which surrounds the test portion and is heated to the Curie-point temperature to pyrolyse the test portion. 6.2.1.3 Platinum-filament pyrolyser, with a holder (pyrolysis probe) containing a platinum filament which surrounds the test portion and is heated to p
35、yrolyse the test portion. 6.2.3 Gas chromatograph A wide variety of chromatographs using either a flame-ionization detector (FID) or a thermal conductivity detector (TCD) are suitable for use in this part of ISO 7270. Selective detectors such as ECD (electron capture detector), FPD (flame photometri
36、c detector), FTD (flame thermionic detector), AED (atomic emission detector) can give useful information. For identification of pyrolysis products, a mass spectrometer detector can be utilized. 6.2.4 Chromatographic columns A variety of column lengths and diameters and stationary and liquid phases a
37、re suitable for use in this part of ISO 7270, the main requirement being good resolution of the volatile pyrolysis products. NOTE 1 Capillary columns with good separation efficiency are suitable, but not essential. NOTE 2 Capillary columns containing non-polar polydimethylsiloxanes and partially mod
38、ified (diphenyl-, cyanopropylphenyl- or other) semi-polar silicones are suitable. NOTE 3 Usually, capillary columns require little evaluation, while it often is necessary to evaluate many conditions for polar and non-polar packed columns. The conditions chosen will depend on the column used. Typical
39、 operating conditions for the gas chromatograph with both polar and non-polar columns can be found in Tables 1 to 5. Typical pyrograms obtained can be found in Figures 1 to 44. 6.2.5 Data-handling equipment A recorder, an integrator or a computer data-analysis system may be used. 7 Procedure 7.1 Acc
40、urate comparison of the pyrogram of an unknown polymer with the reference is only possible under the same conditions. 7.2 Extraction of test samples is recommended to remove additives which may interfere with the chromatographic separation. For oil-extended materials, extraction of the extender oil
41、is essential otherwise this oil may cause serious interference in the pyrogram. Carry out the extraction following the general principles of either method A or method B in ISO 1407:1992. The chosen solvent shall not affect the polymer and shall remove as much of the additives as possible. After extr
42、action, dry the test sample, as residual solvent may cause interference with the pyrolysis products (see 8.4). 7.3 Take a test portion of mass appropriate to the apparatus used. Generally, this will be between 0,1 mg to 5 mg. For good reproducibility, the size of the test portion should be as small
43、as practicable. 7.4 Place the test portion in the pyrolysis device and pyrolyse. An appropriate pyrolysis temperature is 400 C to 800 C for a micro-furnace or Curie-point pyrolyser, and 800 C to 1 200 C for a platinum-filament pyrolyser. 7.5 Record the pyrogram for comparison with the pyrogram of a
44、known polymer or polymer blend obtained under the same conditions. ISO 7270-1:2003(E) ISO 2003 All rights reserved 58 Interpretation of results 8.1 Each polymer will be characterized by the retention times of its main peaks. Some polymers produce characteristic hydrocarbons and their identification
45、is relatively easy. Examples of this type are as follows: a) polyisoprene, which yields mainly isoprene and dipentene (isoprene dimer); b) styrene-butadiene copolymers, which yield mainly butadiene, 4-vinyl-1-cyclohexene (butadiene dimer) and styrene; c) polybutadiene, which yields mainly butadiene
46、and 4-vinyl-1-cyclohexene (butadiene dimer); d) isobutene-isoprene copolymers, which yield mainly isobutene. 8.2 Some polymers do not yield characteristic hydrocarbons, and careful inspection of the pyrogram is required. Supplementary tests, such as those for halogen and nitrogen, may be an aid to m
47、ore definite identification. 8.3 The characteristic hydrocarbons in the unknown polymer are identified by comparison of retention times for a known blend of polymer, or by direct injection of the pure hydrocarbon into the chromatograph. Results may be tabulated for ready reference. 8.4 The analyst s
48、hould be aware of additives which may not be extractable and which may or may not affect the chromatographic pattern. 9 Test report The test report shall contain the following information: a) all details necessary for full identification of the sample analysed; b) the type of pyrolysis device used;
49、c) the pyrolysis temperature; d) the gas-chromatographic conditions used; e) the data-handling equipment used; f) the polymer or polymer blend found in the sample. ISO 7270-1:2003(E) 6 ISO 2003 All rights reservedTable 1 List of pyrograms contained in this part of ISO 7270 Number of figure Micro- furnace Curie point Micro- furnace Curie point Group Rubber (example) Semi-polar capillary column Semi-polar capillary column Polar packed column Non-polar packed column Group M CM Chlorinated polyethylene 1
