1、Designation: D 5028 09Standard Test Method forCuring Properties of Pultrusion Resins by ThermalAnalysis1This standard is issued under the fixed designation D 5028; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last re
2、vision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers determination of curing param-eters of pultrusions resins by differential scanning calorimetry.1.2 Th
3、is test method is applicable to pultrusion resin solu-tions with adequate initiator(s).1.3 The normal operating temperature range is from 0 to200C.NOTE 1Resin systems that do not form an adequate baseline are notcovered by this test method.1.4 Computer or electronic based instruments or data treat-m
4、ent equivalent to this practice may also be used.1.5 The values stated in SI units are to be regarded asstandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate sa
5、fety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements, see Note 1.NOTE 2There is no known ISO equivalent to this test method.2. Referenced Documents2.1 ASTM Standards:2D 3418 Test Method for Transition Temperatures and En-tha
6、lpies of Fusion and Crystallization of Polymers byDifferential Scanning CalorimetryD 3918 Terminology Relating to Reinforced Plastic Pul-truded ProductsE 473 Terminology Relating to Thermal Analysis and Rhe-ologyE 967 Test Method for Temperature Calibration of Differ-ential Scanning Calorimeters and
7、 Differential ThermalAnalyzersE 2160 Test Method for Heat of Reaction of ThermallyReactive Materials by Differential Scanning Calorimetry3. Terminology3.1 Definitions:3.1.1 onset temperaturean extrapolated point representingan intersection of the baseline and the front slope of theexothermic curing
8、curve.3.1.2 peak temperaturean extrapolated point representingan intersection of both front and rear slopes of the exothermiccuring curve.4. Summary of Test Method4.1 The test method consists of heating of the test materialat a controlled rate of temperature increase in a controlledatmosphere and co
9、ntinuously monitoring with a suitable sens-ing device the difference in heat input between a referencematerial and a test material due to changes of state in thematerial. A curing transition is marked by a release of energyby the specimen resulting in a corresponding exothermic curve.NOTE 3Toxic or
10、corrosive effluents, or both, may be released whenheating the material, and could be harmful to the personnel or to theapparatus.5. Significance and Use5.1 Differential scanning calorimeters are used to determinechemical reaction thermal profiles of materials. One suchreaction is the curing of therm
11、osetting resins.5.2 This test method is useful for both specification accep-tance and for research.6. Apparatus6.1 Differential Scanning Calorimeter, capable of heating atest specimen and a reference material at a controlled rate up toat least 20C/min and of automatically recording the differen-tial
12、 heat flow.6.2 Specimen Holders, composed of clean aluminum or ofother high thermal conductivity material.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.18 on Reinforced Thermoset-ting Plastics.Current edition approve
13、d Sept. 1, 2009. Published September 2009. Originallyapproved in 1989. Last previous edition approved in 2003 as D 5028 - 96(2003)1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inform
14、ation, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2.1 Specimen holders may be open, covered, or sealedtype.6.3 Nitrogen, or other inert purge gas supply.6.4 Flowm
15、eter, for purge gas.6.5 Recording Charts, for temperature recording apparatuswith suitable graduation for measurements of energy differen-tial against temperature or time.7. Technical Hazards7.1 An increase or decrease in heating rate from thosespecified may alter the test results. This practice ass
16、umes lineartemperature indication.7.2 Since milligram quantities of sample are used, it isessential to ensure that samples are homogeneous and repre-sentative.7.3 Sample sizes larger than those specified in the testmethod may alter the test results.7.4 For comparison, the same heating rate, the same
17、 samplesize and the same type of pan and lid shall be used.7.5 For low viscosity resin systems, a sealed type of pan andlid shall be used to prevent excessive volatile componentevaporation during the test.8. Test Specimen8.1 Thermoset resin system containing initiator(s) capableof curing in range fr
18、om room temperature to 200C.8.2 Following the addition of initiator, the sample shall beheld for a minimum of12 h before commencing the test.9. Calibration9.1 Using the same heating rate to be used for samples,calibrate the apparatus with appropriate standard referencematerials. For temperature rang
19、e of this standard, the followingmaterial may be used (NIST or equivalent quality):Standard_Melting Point, C_Indium 156.410. Procedure10.1 Weigh a sample of 5 to 10 mg.10.1.1 Crimp a flat metal cover against the pan with thesample sandwiched between them to ensure good heat transfer.Take care to ens
20、ure that the cover contacts the resin surface.Place sample in the DSC cell.10.1.2 Intimate thermal contact between the sample andclean thermocouple or other temperature probe is essential forreproducible results.10.1.3 It is recommended to balance the energy flow into orout of the sample. Start the
21、heating cycle when no movementof the recording pen is visible.10.2 Select appropriate x and y axis sensitivities to yield anarea of 30 to 60 cm3(5 to 10 in.2) under the curing exotherm.10.3 Purge the cell with nitrogen at 60 to 80 mL/min gasflow rate.10.4 Perform and record the thermal cycle by heat
22、ing thesample at a rate of 10C/min under the nitrogen atmospherefrom ambient to temperature high enough to achieve the entireexothermic curing curve information.10.5 Measure the corrected temperatures for the desiredpoints on the curves: To, Tp(see Fig. 1),where:To= extrapolated onset temperature, C
23、, andTp= extrapolated peak temperature, C.11. Report11.1 Report the following information:11.1.1 Complete identification and description of the mate-rial tested, including source, and manufacturers code,11.1.2 Description of instrument used for the test,11.1.3 Statement of the mass, dimension, geome
24、try, andmaterials of the sample holder, and the heating rate used,11.1.4 Description of calibration procedure,11.1.5 Identification of the sample atmosphere by gas flowrate, purity, and composition, and11.1.6 Values of the transition measured using the tempera-ture parameters (To, Tp) cited in Fig.
25、1.12. Precision312.1 This precision data was generated as part of an industryround-robin between eight participating laboratories usingresins from various suppliers standard inventory.12.2 Repeatability (r)the critical difference within whichtwo averages of three observations each, obtained on the s
26、amematerial by a single operator using the same instrument, can beexpected to lie 95 % of the time because of random variationwithin a laboratory.12.2.1 The following criteria were established from tests ofthe resins indicated:3Supporting data are available from ASTM Headquarters. Request RR:D20 116
27、0.FIG. 1 Typical Exothermic Curing CurveD5028092IsophthalicPolyester AIsophthalicPolyester B Vinyl EsterOn-setTemperature, C Unfilled: 2.2 2.0 2.6Filled: 2.0 1.6 1.2PeakTemperature, C Unfilled: 1.4 2.9 2.4Filled: 1.3 2.2 1.112.2.2 If the results and average working data on a givensample tested in th
28、e same laboratory differ by more than thevalues indicated in 12.2.1, the averages can be consideredsignificantly different.12.3 Reproducibility (R)the critical difference withinwhich two averages of three observations each, obtained bytwo different operators using different instruments in differentl
29、aboratories, can be expected to lie 95 % of the time because ofvariation within and between laboratories.12.3.1 The following criteria were established for the resinsindicated:IsophthalicPolyester AIsophthalicPolyester B Vinyl EsterOn-setTemperature, C Unfilled: 3.8 3.4 3.1Filled: 2.6 4.6 2.3PeakTem
30、perature, C Unfilled: 2.8 5.2 3.9Filled: 2.7 3.9 4.312.3.2 If the results and average working data on a givensample test from different laboratories differ by more than thevalues indicated in 12.3.1, the averages can be consideredsignificantly different.ASTM International takes no position respectin
31、g the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standa
32、rd is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Internationa
33、l Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.Th
34、is standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax)
35、, or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 1 DSC Indium Calibration SummaryParticipantMeasured IndiumMelting PointCorrectionFactorDSC InstrumentationAshland 157.8 1.2 duPont 9900Cargil 156.3 +0.3 Perkin Elmer DSC 4Dow Chemical 158.8 2.2 duPont 1090Koppers 157.7 1.
36、1 Perkin Elmer DSC-2CMMFG 156.4 +0.2 Omnitherm QC .25OCF 156.0 +0.6 duPont 1090PPG 157.0 0.4 Perkin Elmer 7R. D. Werner 155.6 +1.0 Omnitherm QC .25Indium Standard 156.6 TABLE 2 On-Set Temperature Precision Data Calculations Basedon “Original” Test ValuesMaterialMeanAverage, XOverall RelativeStandard
37、Deviation ofPrecision TestMethod, VR,%RepeatabilityInterval, IrRepeatabilityInterval, IR1 93.07 0.815 2.148 4.3812 92.47 0.751 1.967 4.1713 95.32 0.729 1.967 4.3704 96.35 0.582 1.585 5.6975 102.82 0.878 2.558 4.2226 102.41 0.400 1.160 4.590TABLE 3 Peak Temperature Precision Data Calculations Basedon
38、 “Adjusted Test ValuesMaterialMeanAverage, XOverall RelativeStandardDeviation ofPrecision TestMethod, VR,%RepeatabilityInterval, IrRepeatabilityInterval, IR1 92.72 0.818 2.148 3.7842 92.12 0.754 1.967 2.6353 94.97 0.731 1.967 3.3544 96.00 0.584 1.585 4.5875 102.47 0.882 2.558 3.0686 102.06 0.401 1.1
39、60 2.270TABLE 4 Peak Temperature Precision Data Calculations Basedon “Original Test ValuesMaterialMeanAverage, XOverall RelativeStandardDeviation ofPrecision TestMethod, VR,%RepeatabilityInterval, IrRepeatabilityInterval, IR1 105.57 0.454 1.356 3.5432 105.45 0.418 1.248 3.5693 107.85 0.958 2.929 5.5
40、524 107.36 0.725 2.202 4.5055 112.28 0.759 2.408 4.6276 111.62 0.344 1.087 6.011TABLE 5 Peak Temperature Precision Data Calculations Basedon “Adjusted Test ValuesMaterialMeanAverage, XOverall RelativeStandardDeviation ofPrecision TestMethod, VR,%RepeatabilityInterval, IrRepeatabilityInterval, IR1 105.35 0.455 1.356 2.8332 105.10 0.420 1.248 2.7343 107.50 0.961 2.929 5.2074 107.01 0.727 2.202 3.9035 111.93 0.762 2.408 3.9396 111.27 0.345 1.087 4.299D5028093
