1、BRITISH STANDARD BS EN 12614:2004 Products and systems for the protection and repair of concrete structures Test methods Determination of glass transition temperatures of polymers The European Standard EN 12614:2004 has the status of a British Standard ICS 91.080.40 BS EN 12614:2004 This British Sta
2、ndard was published under the authority of the Standards Policy and Strategy Committee on 14 October 2004 BSI 14 October 2004 ISBN 0 580 44592 5 National foreword This British Standard is the official English language version of EN 12614:2004. The UK participation in its preparation was entrusted by
3、 Technical Committee B/517, Concrete, to Subcommittee B/517/8, Protection and repair of concrete structures, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement i
4、nternational or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not
5、purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European comm
6、ittee 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. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to
7、9 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN12614 October2004 ICS91.080.40 Englishversion Productsandsystemsfortheprotec
8、tionandrepairofconcrete structuresTestmethodsDeterminationofglasstransition temperaturesofpolymers Produitsetsystmespourlaprotectionetlarparationdes structuresenbtonMthodesdessaiDterminationde latempraturedetransitionvitreuse ProdukteundSystemefrdenSchutzunddie InstandsetzungvonBetontragwerkenPrfver
9、fahren BestimmungderGlasbergangstemperaturvonPolymeren ThisEuropeanStandardwasapprovedbyCENon27February2004. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibli
10、ographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheCentralSecretariatortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifie
11、dtotheCentralSecretariathasthesamestatusast heofficial versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,Cyprus,CzechRepublic,Denmark,Estonia,Finland,France, Germany,Greece,Hungary,Iceland,Ireland,Italy,Latvia,Lithuania,Luxembourg,Malta,Netherlands,Norway,Poland,Portugal, Slovakia,
12、Slovenia,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2004CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN12614:2
13、004:EEN 12614:2004 (E) 2 Contents page Foreword3 1 Scope4 2 Terms and definitions .4 3 Test principle4 4 General requirements for testing.5 4.1 Apparatus.5 4.2 Calibration of the temperature scale of the apparatus 5 5 Preparation of sample .6 5.1 General6 5.2 Powdered or granular sample 6 5.3 Moulde
14、d or pelleted samples .6 5.4 Film or sheet samples .6 6 Test procedure.6 7 Test report9 EN 12614:2004 (E) 3 Foreword This document (EN 12614:2004) has been prepared by Technical Committee CEN /TC 104, “Concrete and related products“, the secretariat of which is held by DIN. It has been elaborated by
15、 Sub-Committee 8 “Products and systems for the protection and repair of concrete structures“ (Secretariat AFNOR). 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 April 2005, and conflicting nation
16、al standards shall be withdrawn at the latest by April 2005. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
17、Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 12614:2004 (E) 4 1 Scope This document covers a test method for the determination of glass transition
18、temperature (GTT) of polymers by differential scanning calorimetry (DSC) or differential thermal analysis (DTA). This test method is applicable to polymers in granular form (below 60 mesh, 250 , avoiding grinding if possible) or to any fabricated shape from which appropriate samples can be cut. This
19、 test method is useful for specification acceptance. This test method determines the structural behaviour of a polymer according to the variations of temperatures. 2 Terms and definitions For the purposes of this document, the following terms and definitions apply. 2.1 differential scanning calorime
20、try (DSC) differential scanning calorimetry can be carried out according to two principles, depending on the method of measurement used Power compensation differential scanning calorimetry records in function of time or temperature the required power to maintain a zero temperature difference between
21、 the polymer and an inert reference, when they are subjected to a controlled temperature program (Power-compensation DSC). Heat-flux differential scanning calorimetry records in function of time or temperature the difference of heat-flux diffusing between the sample holder, the reference holder and
22、the testing unit of the equipment (Heat-flux DSC). For the two principles, the recording chart gives a DSC curve with, at the Y-axis, the heat flow and, at the X-axis, the temperature or time. 2.2 differential thermal analysis (DTA) differential thermal analysis records the temperature difference be
23、tween the polymer sample and an inert reference, while they are subjected to a controlled temperature program The recording chart gives a DTA curve with, at the Y-axis, the temperature difference between the sample and the reference and, at the X-axis, the temperature or time. 3 Test principle The t
24、est method consists of heating or cooling the sample at a controlled rate in a controlled atmosphere. A suitable sensing device monitors continuously: temperature difference between the sample and the reference for differential thermal analysis; power or heat-flux changes for differential scanning c
25、alorimetry. Glass transition of the sample is characterized on the recording chart by a change of the baseline during the heating or the cooling. The test shall be carried out under an inert blanket (nitrogen) to avoid any reaction of the sample with air during the temperature cycle. The output of t
26、he inert gas shall be controlled by a flowmeter. In addition, some polymers can react near the transition temperature; care shall be used to distinguish between reaction and transition. EN 12614:2004 (E) 5 4 General requirements for testing 4.1 Apparatus 4.1.1 Differential thermal analyzer or differ
27、ential scanning calorimeter capable of heating or cooling at rates up to at least (10 1) K/min and of automatically recording any difference in temperature (or difference in heat input) between the sample and a reference material, to the required sensitivity and precision. Increasing the heating rat
28、e has been found to produce sharper transition curves. For comparison the same heating rate shall be used. 4.1.2 Sample tubes or pans or other sample holders made of aluminium or other metal of high thermal conductivity shall be used, unless the product is aggressive toward this, in which cases boro
29、silicate glass shall be used. 4.1.3 The measuring head shall be provided by a probe or thermocouple the reference temperature of which is obtained by putting one of the solderings in a stirred bath of ice/water or by an electronic device. 4.1.4 Reference material - glass beads, alumina powder, silic
30、on carbide, or any material known to be unaffected by repeated heating - cooling and free from interfering transitions. The thermal diffusivity of the reference should be as close as possible to that of the sample. 4.1.5 Recording charts for temperature recording apparatus, with suitable graduations
31、 for measurement of either temperature differential or energy differential against temperature or time. 4.1.6 Nitrogen or other inert gas supply, for blanketing sample. 4.2 Calibration of the temperature scale of the apparatus Using the same heating rate to be used for samples, calibrate the tempera
32、ture scale of the apparatus with appropriate standard reference materials (Analytical Reagents) covering the temperature range of interest. For many commercial polymers, this range may be defined by the following substances (see Table 1). Table 1 Melting points of reference materials Standard Meltin
33、g point (K) n-heptane 182,65 n-octane 216,35 n-decane 242,85 Water 273,15 Benzoc acid 395,55 Indium 429,55 Tin 505,05 Lead 600,55 Zinc 692,65 When lead is used as a standard, a fresh sample should be used each time. EN 12614:2004 (E) 6 5 Preparation of sample 5.1 General Sample shall be homogeneous
34、and representative. 5.2 Powdered or granular sample Avoid grinding if preliminary thermal cycles as outlined in 6.2 is not performed. Grinding or similar techniques for size reduction often introduce thermal effects because of friction or orientation, or both, and thereby change the thermal history
35、of the sample. 5.3 Moulded or pelleted samples Cut the samples with a microtome, razor blade, hypodermic punch, paper punch, or cork borer (size No 2 or 3) to appropriate size, in thickness or diameter and length that will best fit the sample holder and will approximate the desired weight in the sub
36、sequent procedure. 5.4 Film or sheet samples For films thicker than 0,04 mm see 5.3. For thinner films, cut slivers to fit in the sample tubes or punch disks, if circular sample pans are used. 6 Test procedure 6.1 Sample weight Use a sample weight appropriate for the material to be tested. In most c
37、ases sample weights of 10 mg to 20 mg for DSC, 10 mg to 100 mg for DTA are satisfactory. NOTE Since milligram quantities of sample are used it is essential to ensure that samples are homogeneous and representative. 6.2 Preliminary thermal cycle The preliminary thermal cycle involves heating of the s
38、ample at a rate of 10 K/min under nitrogen inert gas with a controlled flow adapted to the apparatus, from ambient temperature to 30 K above the melting point or up to a temperature high enough to erase previous thermal history. The time of exposure to high temperature shall be minimized, to avoid s
39、ublimation or decomposition of the sample. The selection of this temperature and duration of maintaining are crucial in case of studies about tempering. The preliminary thermal cycle may interfere with the transition of interest, causing an incorrect transition or eliminating a transition. Where it
40、has been shown that this effect is present, omit the preliminary thermal cycle. 6.3 Quench cooling Quench cool to 50 K below the transition temperature of interest. Hold temperature for 10 min. EN 12614:2004 (E) 7 6.4 Test thermal cycle Repeat heating (6.2) at a rate of 10 K/min, and record the heat
41、ing curve until all desired transitions have been completed. Measurements below ambient temperature may be carried out by cooling down the apparatus by the means of liquid nitrogen - as far as the apparatus is designed for this technique - followed by the same temperature cycle as described above. 6
42、.5 Measurements Measure defined temperature Tf, Tg, Te, Tm (see Figure 1): where Tf is extrapolated onset temperature, in K; Tg is glass transition temperature, in K; Te is extrapolated end temperature, in K; Tm is mid point temperature, in K. The temperature at which a tangent to the curve intercep
43、ts an extension of the base line on the low temperature side shall be designated Tf, and the temperature at which a tangent to the curve interceps on extension of the base line on the high temperature side shall be designated Te. Tm is the mid point temperature, defined at 2 h , h being the distance
44、 between Tf and Te, measured parallel to the ordinate. The glass transition temperature, Tg, is defined equal to Tm. However for most applications the Tf temperature is more meaningful and may be used as Tg in place of the midpoint of the Tg temperature. Devices which calculate the above given tempe
45、ratures, automatically or semi automatically, after putting in the straight lines by the means of a computer should work in a comparable manner. EN 12614:2004 (E) 8 Key Y Heat flow (mJ/sec) (DSC) Temperature difference (K) (DTA) X Temperature (K) Figure 1 Typical glass transition 6.6 Precision Dupli
46、cate determinations of glass transition temperatures on two specimens of the same sample by the same analyst should not differ more than 2,5 K. 6.7 Reproducibility Duplicate determination of glass transition temperatures on specimens of the same sample analysed in different laboratories should not d
47、iffer by more than 4 K. EN 12614:2004 (E) 9 7 Test report The test report shall include the following information : a) complete identification of the injection product or system tested, including source, manufacturers code numbers and history; b) date of the test; c) name and address of the testing
48、laboratory; d) identification number, date of test report and signature; e) complete indication and description of the material tested, including manufacturers code; f) description of instructions used for the test; g) reference to this document; h) statement of the dimensions, geometry, and materials of the sample holder ; and the average rate of linear temperature change; i) statement of the weight of the sample; j) description of temperature calibration procedure; k) nature of the reference material in ATD; l) ide
