BS EN ISO 11357-4-2014 Plastics Differential scanning calorimetry (DSC) Determination of specific heat capacity《塑料 差示扫描量热法(DSC) 比热容的测定》.pdf

1、BSI Standards PublicationBS EN ISO 11357-4:2014Plastics - Differential scanningcalorimetry (DSC)Part 4: Determination of specific heatcapacityBS EN ISO 11357-4:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO11357-4:2014. It supersedes BS EN ISO 11357-4:

2、2013 which iswithdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/21, Testing of plastics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of

3、a contract. Users are responsible for its correctapplication. The British Standards Institution 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 84698 4ICS 83.080.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the

4、 authority of theStandards Policy and Strategy Committee on 31 July 2014.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 11357-4 June 2014 ICS 83.080.01 Supersedes EN ISO 11357-4:2013English Version Plastics - Differential scanning calori

5、metry (DSC) - Part 4: Determination of specific heat capacity (ISO 11357-4:2014) Plastiques - Analyse calorimtrique diffrentielle (DSC) - Partie 4: Dtermination de la capacit thermique massique (ISO 11357-4:2014) Kunststoffe - Dynamische Differenz-Thermoanalyse (DSC) -Teil 4: Bestimmung der spezifis

6、chen Wrmekapazitt (ISO 11357-4:2014) This European Standard was approved by CEN on 10 July 2014. 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-

7、date lists and bibliographical references concerning such national standards 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 translati

8、on under the responsibility of a CEN member into its own language and 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, F

9、ormer Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COM

10、IT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 11357-4:2014 EBS EN ISO 11357-4:2014EN ISO 11357-4

11、:2014 (E) 3 Foreword This document (EN ISO 11357-4:2014) 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, eit

12、her by publication of an identical text or by endorsement, at the latest by December 2014, and conflicting national standards shall be withdrawn at the latest by December 2014. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN a

13、nd/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 11357-4:2013. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: A

14、ustria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sw

15、eden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 11357-4:2014 has been approved by CEN as EN ISO 11357-4:2014 without any modification. BS EN ISO 11357-4:2014ISO 11357-4:2014(E) ISO 2014 All rights reserved iiiContents PageForeword iv1 Scope . 12 Normative referen

16、ces 13 Terms and definitions . 14 Principle 24.1 General . 24.2 Continuous-scanning method 34.3 Stepwise-scanning method 45 Apparatus . 46 Test specimen 47 Test conditions and specimen conditioning 48 Procedure. 48.1 Selection of crucibles . 48.2 Setting up the apparatus and adjustment of isothermal

17、 baselines . 58.3 Measurement of specific heat capacity of calibration material 68.4 Specimen run 79 Determination of specific heat capacities 79.1 Calculation of specific heat capacities. 79.2 Numerical rounding of the results . 710 Precision and bias . 811 Test report . 8Annex A (informative) An a

18、pproximate expression of the specific heat capacityof pure -alumina 3 to 5. 9Bibliography .12BS EN ISO 11357-4:2014ISO 11357-4:2014(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Int

19、ernational 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 organizations, governmental and non-governmental, in liaison w

20、ith ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directive

21、s, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directivesAttention is drawn to the possibility that some of the e

22、lements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations rece

23、ived. www.iso.org/patentsAny trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence

24、 to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 61, Plastics, Subcommittee SC 5, Physical and chemical properties.This second edition cancels and replaces the first editi

25、on (ISO 11357-4:2005). This minor revision contains the following changes:a) all normative reference were changed into undated ones;b) the term “pan” was replaced by “crucible” within the whole text;c) the endothermic direction, a, was added in all figures and key.ISO 11357 consists of the following

26、 parts, under the general title Plastics Differential scanning calorimetry (DSC): Part 1: General principles Part 2: Determination of glass transition temperature and glass transition step height Part 3: Determination of temperature and enthalpy of melting and crystallization Part 4: Determination o

27、f specific heat capacity Part 5: Determination of characteristic reaction-curve temperatures and times, enthalpy of reaction and degree of conversion Part 6: Determination of oxidation induction time (isothermal OIT) and oxidation induction temperature (dynamic OIT) Part 7: Determination of crystall

28、ization kineticsiv ISO 2014 All rights reservedBS EN ISO 11357-4:2014INTERNATIONAL STANDARD ISO 11357-4:2014(E)Plastics Differential scanning calorimetry (DSC) Part 4: Determination of specific heat capacity1 ScopeThis part of ISO 11357 specifies methods for determining the specific heat capacity of

29、 plastics by differential scanning calorimetry.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for the application of this document. For undated references, the latest edition of the referenced document (including

30、any amendments) applies.ISO 472, Plastics VocabularyISO 11357-1, Plastics Differential scanning calorimetry (DSC) Part 1: General principlesISO 80000-1, Quantities and units Part 1: General3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 472 and ISO 11

31、357-1 and the following apply.3.1calibration materialmaterial of known specific heat capacityNote 1 to entry: Usually, -alumina (such as synthetic sapphire) of 99,9 % or higher purity is used as the calibration material.3.2specific heat capacity (at constant pressure)cpquantity of heat necessary to

32、raise the temperature of unit mass of material by 1 K at constant pressureNote 1 to entry: It is given by the following formula:cp= m1Cp= m1(dQ/dT)p(1)where ISO 2014 All rights reserved 1BS EN ISO 11357-4:2014ISO 11357-4:2014(E)m is the mass of material;cpis the heat capacity and is expressed in kil

33、ojoules per kilogram per K (kJkg1K1) or in joules per gram per K (Jg1K1); subscript p indicates an isobaric process;dQ is the quantity of heat necessary to raise the temperature of the material by dT;Note 2 to entry: This formula is valid in a temperature range where a material shows no first-order

34、phase transition.(dQ/dT) = (dt/dT) (dQ/dt) = (heating rate)1 (heat flow rate) (2)Note 3 to entry: At phase transitions, there is a discontinuity in the heat capacity. Part of the heat is consumed to produce a material state of higher energy and it is not all used in raising the temperature. For this

35、 reason, the specific heat can only be determined properly outside regions of phase transitions.4 Principle4.1 GeneralEach measurement consists of three runs at the same scanning rate (see Figure 1):a) a blank run (empty crucibles in sample and reference holders);b) a calibration run (calibration ma

36、terial in sample holder crucible and empty crucible in reference holder);c) a specimen run (specimen in sample holder crucible and empty crucible in reference holder).2 ISO 2014 All rights reservedBS EN ISO 11357-4:2014ISO 11357-4:2014(E)KeyX temperature T or time t1 blank run2 calibration run3 spec

37、imen runI isothermal baseline at start temperature TsII isothermal baseline at end temperature TfaEndothermic direction.Figure 1 Schematic drawing of typical DSC curves for specific heat capacity measurement (blank, calibration and specimen runs) after baseline adjustment4.2 Continuous-scanning meth

38、odBased on the DSC principle (see ISO 11357-1) and the definition of specific heat capacity given in 3.2, the following relations can be obtained:mc PPsppspspecimenrunblankrun (3)mc PPcalpcalcalibrationrun blankrun (4)where P is the heat flow rate (dQ/dt); superscripts sp and cal represent specimen

39、and calibration material, respectively (see Figure 1).When Pspecimen run, Pcalibration runand Pblank runare measured, cpspcan be calculated using Formula (6), since the values of cpcal, mspand mcalare known:mcmcPPsppspcalpcalspecimenrunblankruncalibrationrun=bblankrun(5)ccmP PmPpsppcalcalspecimenrun

40、blankrunspcalibrationrun=()Pblankrun(6) ISO 2014 All rights reserved 3BS EN ISO 11357-4:2014ISO 11357-4:2014(E)4.3 Stepwise-scanning methodIn the stepwise-scanning method, the total temperature range to be scanned is divided into small intervals and a complete determination consisting of the three r

41、uns mentioned in 4.1 is performed for each temperature interval. Upon integration of the heat flow rate curve, the total heat Q consumed in the interval can be obtained. Dividing Q by the temperature interval T and the mass of the specimen gives the specific heat see Formula (1):mcQTQTsppspsppblankp

42、(7)mcQTQTcalpcalcalpblankp(8)Keeping the temperature intervals T constant, combining Formulae (7) and (8) results in:ccmmQQQQpsppcalcalspsp blankcalblank= (9)5 Apparatus5.1 DSC apparatus. See ISO 11357-1.5.2 Crucibles. See ISO 11357-1.The crucibles for the test specimen and the reference specimen (c

43、alibration material) shall be of the same shape and material and their masses shall not differ by more than 0,1 mg.NOTE The same blank run and calibration run can be used for several measurements, if the instrument is sufficiently stable and the difference in mass between the calibration material cr

44、ucible and the empty crucible is corrected for. An adequate correction can be obtained by adding the term cp, crucible(T)m to the heat flow rate of the calibration run, where cp,crucible(T) is the specific heat capacity of the calibration crucible as a function of temperature, is the heating rate an

45、d m is the difference in mass between the calibration crucible and the empty crucible. The same procedure can also be used for correcting differences in mass between the specimen run and the blank run.5.3 Analytical balance. See ISO 11357-1.6 Test specimenSee ISO 11357-1.7 Test conditions and specim

46、en conditioningSee ISO 11357-1.8 Procedure8.1 Selection of cruciblesPrepare three crucibles and their lids and weigh the crucibles together with their lids. The total mass shall not differ by more than 0,1 mg (see 5.2). In other respects, such as material, size, crucible type (open or sealed), the c

47、rucibles shall be identical.4 ISO 2014 All rights reservedBS EN ISO 11357-4:2014ISO 11357-4:2014(E)8.2 Setting up the apparatus and adjustment of isothermal baselines8.2.1 Place a pair of empty crucibles with lids in the DSC sample and reference holders.8.2.2 If using a continuous-scan programme:a)

48、Set the start and end temperatures (Tsand Tf). The start temperature Tsshould be at least 30 K lower than that at which data are first required.NOTE 1 When more precise results are required over a wide temperature range, the overall range can be divided into two (or more) smaller ranges, each 50 K t

49、o 100 K wide. The start temperature Tsof the second range should be 30 K lower than the end temperature Tfof the first temperature range to ensure sufficient overlap.b) Set the scanning rate.c) Set the time interval between the isothermal stages I and II (see Figure 1) and allow the respective isothermal baselines to stabilize. This interval will usually be between 2 min and 10 min.NOTE 2 Some calorimeters, e.g. those of