DIN EN ISO 10927-2011 Plastics - Determination of the molecular mass and molecular mass distribution of polymer species by matrix-assisted laser desorption ionization time-of-fligh1.pdf

1、July 2011 Translation by DIN-Sprachendienst.English price group 11No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 8

2、3.080.01!$sSq“1804878www.din.deDDIN EN ISO 10927Plastics Determination of the molecular mass and molecular mass distribution ofpolymer species by matrix-assisted laser desorption/ionizationtime-of-flight mass spectrometry (MALDI-TOF-MS) (ISO 10927:2011)English translation of DIN EN ISO 10927:2011-07

3、Kunststoffe Bestimmung der Molmasse und Molmassenverteilung von polymeren Species durchmatrixuntersttzte Laser-Desorptions/Ionisations-Flugzeit-Massenspektrometrie(MALDI-TOF-MS) (ISO 10927:2011)Englische bersetzung von DIN EN ISO 10927:2011-07Plastiques Dtermination de la masse molculaire et de la d

4、istribution des masses molculaires despolymres par spectromtrie de masse, temps de vol, aprs dsorption/ionisation laserassiste par matrice (SM-MALDI-TOF) (ISO 10927:2011)Traduction anglaise de DIN EN ISO 10927:2011-07SupersedesDIN 55674:2006-12www.beuth.deDocument comprises pagesIn case of doubt, th

5、e German-language original shall be considered authoritative.1907.11 DIN EN ISO 10927:2011-07 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee ISO/TC 61 “Plastics”, Subcommittee SC 5 “Physical-chemical properties” (Secretariat: DIN, Ge

6、rmany) in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was the Normenausschuss Beschichtungsstoffe und Beschichtungen (Coatings and Coating Materials Standards Committee), Working Committ

7、ee NA 002-00-02 AA Lackrohstoffe, Working Group NA 002-00-02-03 AK Gelpermeationschromatographie. The DIN Standard corresponding to the International Standard referred to in this document is as follows: ISO 472 DIN EN ISO 472 Amendments This standard differs from DIN 55674:2006-12 as follows: a) the

8、 text of ISO 10927:2011 has been adopted without any modification; b) the number of the standard has been changed from DIN 55674 to DIN EN ISO 10927; c) in Clause 1 “Scope”, the molecular mass has been modified; d) Subclause 7.2.4 “Preparation and spotting of biopolymer/matrix solutions” has been ad

9、ded. Previous editions DIN 55674: 2006-12 National Annex NA (informative) Bibliography DIN EN ISO 472, Plastics Vocabulary EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 10927 April 2011 ICS 83.080.01 English Version Plastics - Determination of the molecular mass and molecular mass distrib

10、ution of polymer species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) (ISO 10927:2011) Plastiques - Dtermination de la masse molculaire et de la distribution des masses molculaires des polymres par spectromtrie de masse, temps de vol, aprs dsorption/

11、ionisation laser assiste par matrice (SM-MALDI-TOF) (ISO 10927:2011) Kunststoffe - Bestimmung der Molmasse und Molmassenverteilung von polymeren Species durch matrixuntersttze Laser-Desorptions/Ionisations-Flugzeit-Massenspektrometrie (MALDI-TOF-MS) (ISO 10927:2011)This European Standard was approve

12、d by CEN on 14 April 2011. 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 sta

13、ndards 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

14、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, Lith

15、uania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011

16、CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 10927:2011: EContents EN ISO 10927:2011 (E) DIN EN ISO 10927:2011-07 2 Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Principle6 5

17、Reagents.7 5.1 Matrices 7 5.2 Solvents 7 5.3 Salts 7 5.4 Molecular mass standards7 6 Apparatus .7 6.1 General7 6.2 Sample introduction chamber/target.7 6.3 Laser source.8 6.4 Flight tube.8 6.5 Detector 9 6.6 Data recording9 6.7 Data handling .9 7 Procedure .9 7.1 General9 7.2 Sample preparation .9 7

18、.3 Instrument settings10 7.4 Recording spectra .11 8 Data acquisition and processing .12 8.1 General12 8.2 Calibration 12 8.3 Generation of calibration curve13 8.4 Signal intensity axis calibration.13 9 Expression of results 13 9.1 Calculation of molecular mass distribution13 9.2 Calculation of the

19、average molecular masses13 10 Precision.13 11 Test report 14 Annex A (normative) Calibrants 15 Annex B (informative) Precision data16 Bibliography 17 Foreword This document (EN ISO 10927:2011) has been prepared by Technical Committee ISO/TC 61 Plastics” in collaboration with Technical Committee CEN/

20、TC 139 “Paints and varnishes” the secretariat of which is held by DIN. 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 October 2011, and conflicting national standards shall be withdrawn at the la

21、test by October 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. According to the CEN/CENELEC Internal Regulations, the national

22、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, Norw

23、ay, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 10927:2011 has been approved by CEN as a EN ISO 10927:2011 without any modification. EN ISO 10927:2011 (E) DIN EN ISO 10927:2011-07 3 “Introduction The molecular m

24、ass and molecular mass distribution of a synthetic polymer are fundamental characteristics that result from the polymerization process. They may be used for a wide variety of correlations for fundamental studies and for processing and product applications. Determination of the molecular mass and mol

25、ecular mass distribution is used for quality control of polymers and for specification purposes in the commerce of polymers. The comparability of MALDI-TOF-MS results obtained in different laboratories can be ensured by using standardized conditions of measurement, identical samples and identical ma

26、trix preparation methods. The classification of MALDI-TOF-MS as an equitable (standardized) method compared with other established methods of polymer characterization could result in a significant increase in the use of MALDI-TOF-MS. EN ISO 10927:2011 (E) DIN EN ISO 10927:2011-07 4 1 Scope This Inte

27、rnational Standard specifies a general method for determining the average molecular mass and molecular mass distribution of polymers (see Reference 1) from 2 000 gmol1to 20 000 gmol1by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The average molecular

28、masses and molecular mass distributions are calculated from a calibration curve constructed using synthetic-polymer and/or biopolymer standards. This method is therefore classified as a relative method. The method is not applicable to polyolefins or to polymers with a polydispersity 1,2. 2 Normative

29、 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 472, Plastics Vocabulary 3 Terms

30、and definitions For the purposes of this document, the terms and definitions given in ISO 472 and the following apply. 3.1 matrix-assisted laser desorption/ionization time-of-flight-mass spectrometry MALDI-TOF-MS a mass-spectrometric technique in which the separation is based on different flight tim

31、es in a field free flight tube depending on the mass of formed polymer ions after ionization by a laser, desorption and acceleration by high voltage 3.2 molecular mass M sum of the masses of the atoms making up a molecule NOTE Molecular weight is also used for molecular mass. EN ISO 10927:2011 (E) D

32、IN EN ISO 10927:2011-07 5 3.3 average molecular mass Three possible types of average molecular mass are defined by the following equations, where Niis the number of molecules of species i of molecular mass Mi; miis the mass of the ith species (i.e. mi= NiMi); zi= miMi/mi. 3.3.1 number-average molecu

33、lar mass Mn1n1()iiiiiNMMN=(1) 3.3.2 mass-average molecular mass Mw211w11()()ii iiii iNM mMMNM m=(2) 3.3.3 z-average molecular mass Mz()32111z2111()()ii ii iiii ii iNM mM zMMNM mM z=(3) 4 Principle The MALDI process involves the desorption and the ionization of an analyte dispersed in an organic smal

34、l-molecule matrix. The matrix must be able to absorb the laser energy. A metal salt may be added to cationize the analyte. A polymer is co-crystallized or co-mixed with the matrix molecule and deposited on the target. A short-duration UV laser pulse is used to desorb the matrix and the analyte. The

35、laser energy is transferred to the matrix molecules, causing them to vaporize. Analyte and matrix molecules leave the target surface in a plume. Due to the very short desorption time, polymer molecules do not degrade. The polymer in the desorption plume gains a cation and is accelerated by a high vo

36、ltage, drifts down the field-free flight tube and is detected at the end of the flight tube. The time of flight of the species is a measure of its mass. From the distribution of arrival times and the calibration of the arrival times with known mass standards, the mass distribution of the polymer is

37、determined. EN ISO 10927:2011 (E) DIN EN ISO 10927:2011-07 6 5 Reagents 5.1 Matrices 2,5-dihydroxybenzoic acid (gentisic acid, DHB) and 1,8,9-trihydroxyanthracene (dithranol) are the recommended matrices for this method. All of these materials shall be at least 97 % pure. They shall be stored in a f

38、reezer and warmed to room temperature immediately before use. 5.2 Solvents The recommended solvent is tetrahydrofuran (THF). THF with an antioxidant, such as 2,6-di-tert-butyl-4-methylphenol (dibutylated hydroxytoluene, BHT) at a concentration of 0,025 % to 0,1 % (m/V), shall be stored in an amber c

39、ontainer. If THF without an antioxidant is used, it shall be stored in an amber container under an inert gas. Otherwise, it will react with oxygen to form peroxides which are hazardous on evaporative concentration. Depending on the solubility of the polymer being investigated, toluene, methanol and

40、acetone may also be used. High-purity solvents are recommended. 5.3 Salts Lithium, sodium, potassium and silver trifluoroacetate are recommended since they are soluble in THF and toluene. AgNO3with ethanol as solvent may be used with the polymer and matrix in THF. The salts shall be soluble in the s

41、olvent chosen for the polymer and the matrix. When silver nitrate is used, relevant safety aspects should be borne in mind. 5.4 Molecular mass standards The calibration of the mass spectrometer shall be carried out using biopolymers and/or synthetic polymers with known repeating units and end groups

42、. The molecular masses of the standards shall lie within the range of the molecular mass of the polymer being investigated. The software of the mass spectrometer shall be used for calibration. A list of recommended biopolymers and their molecular masses is given in Annex A. 6 Apparatus 6.1 General A

43、 schematic diagram of a MALDI-TOF mass spectrometer is shown in Figure 1. The main components are a sample introduction chamber, a laser source, an ion source, a flight tube with an acceleration region and an ion detector. The instruments may have additionally an ion deflector and a reflector detect

44、or. Both commercially available TOF mass spectrometers and systems assembled in the laboratory may be used for this method, provided they meet the required levels of performance. 6.2 Sample introduction chamber/target A MALDI test sample consists of a film, containing the analyte, the matrix and a s

45、alt mixture, deposited as so-called “spots” on a metal plate. The entire plate, with the sample spots, is often referred to as the MALDI target. The MALDI target is introduced into the spectrometer vacuum chamber by either a manual or an automatic operation. The target is moveable, so that all the s

46、ample spots on the target are accessible to the laser beam. EN ISO 10927:2011 (E) DIN EN ISO 10927:2011-07 7 412910768531112Key 1 laser source 2 counter 3 optical system with beam splitter and attenuator 4 test sample introduction chamber 5 target 6 ion acceleration optics 7 reflector 8 linear detec

47、tor 9 reflector detector 10 vacuum pump system 11 data recording 12 computer Figure 1 Schematic diagram of a MALDI-TOF mass spectrometer 6.3 Laser source The laser system is comprised of a pulsed laser, an attenuator which allows the adjustment of the laser power, beam splitters to direct a fraction

48、 of the laser light to a photodiode to start the timing for the TOF measurement, and a lens and mirror system to direct the laser beam onto the MALDI target. The wavelength of the laser shall be in the absorption range of the matrix. Typically, UV-lasers are used. 6.4 Flight tube The target is at a

49、high voltage of several kilovolts and situated just behind the acceleration optics. The analyte/matrix/salt mixture is deposited on this target and exposed to the pulsed laser beam. Thereby, gaseous analyte ions are formed which are accelerated by the electric field, exit the source and pass through into the flight tube. The flight tube is a field-free drift region. EN ISO 10927:2011 (E) DIN EN ISO 10927:2011-07 8 6.5 Detector Ion detection in a TOF mass analyser is based on the fast measurement of t