ASTM_D_5028_-_09.pdf

Designation:D502809Standard Test Method forCuring Properties of Pultrusion Resins by ThermalAnalysis1This standard is issued under the fixed designation D5028;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.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 This test method is applicable to pultrusion resin solu-tions with adequate initiator(s).1.3 The normal operating temperature range is from 0 to200C.NOTE1Resin systems that do not form an adequate baseline are notcovered by this test method.1.4 Computer or electronic based instruments or data treat-ment 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 safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specific hazardstatements,see Note 1.NOTE2There is no known ISO equivalent to this test method.2.Referenced Documents2.1 ASTM Standards:2D3418 Test Method for Transition Temperatures and En-thalpies of Fusion and Crystallization of Polymers byDifferential Scanning CalorimetryD3918 Terminology Relating to Reinforced Plastic Pul-truded ProductsE473 Terminology Relating to Thermal Analysis and Rhe-ologyE967 Test Method for Temperature Calibration of Differen-tial Scanning Calorimeters and Differential Thermal Ana-lyzersE2160 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 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 continuously 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.NOTE3Toxic or 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 thermosetting 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 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 approved Sept.1,2009.Published September 2009.Originallyapproved in 1989.Last previous edition approved in 2003 as D5028-96(2003)1.DOI:10.1520/D5028-09.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.2.1 Specimen holders may be open,covered,or sealedtype.6.3 Nitrogen,or other inert purge gas supply.6.4 Flowmeter,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 assumes 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 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 sys