ASTM_D_7029_-_09.pdf

Designation:D702909Standard Test Method forDetermination of Reactivity of Unsaturated Polyesters andVinyl Esters at 180.0F(82.2C)1This standard is issued under the fixed designation D7029;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 standard provides a standardized test method fordetermining the gelation and exotherm curve of unsaturatedpolyester and vinyl ester resins.This method provides guid-ance for measurement of the“Standard 180F(82.2C)Exo-therm Curve”along with information on variances of themeasurement which may be required for special resins.Thistest method provides information concerning the reactivity ofunsaturated polyester and vinyl ester resins as they go throughpolymerization after mixing with the initiator.NOTE1There is no known ISO equivalent to this standard,althoughISO 584 is similar.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in nonconformancewith the standard.1.3 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.2.Referenced Documents2.1 Society of Plastics Industry,Inc.:Handbook of Reinforced Plastics“Procedure for RunningExotherm Curves Using the Block Test Method”2.2 ISO Standard:ISO 584 Reinforced Plastics Based on Unsaturated PolyesterResinsDetermination of Reactivity at 80C23.Terminology3.1 Definitions:3.1.1 gel timethe period of time in minutes and secondsrequired for the recording pyrometer to go from a temperaturebelow(usually 10 to 30F or 5.5 to 16C)bath temperature to10F(5.55C)above the bath temperature,typically 150F(65.5C)to 190F(78.8C)for a bath at 180F(82.2C).3.1.2 cure timethe period of time in minutes and secondsrequired for the recording pyrometer to go from a temperaturebelow(usually 10 to 30F or 5.5 to 16C)bath temperature tothe maximum temperature reading,typically 150F(65.5C)tothe maximum temperature for a bath at 180F(82.2C).3.1.3 interval timethe period of time in minutes andseconds required for the recording pyrometer to go from 10F(5.5C)above the bath temperature to the maximum tempera-ture reading,typically 190F(78.8C)to the maximum tem-perature.Thus,interval time is cure time minus gel time.3.1.4 peak exothermthe maximum temperature reachedduring the testing.3.1.5 recording pyrometera broad class of temperaturemeasuring devices including thermocouples with the ability forcontinuous temperature recording.3.1.6 initiatora compound that generates free radicals tostart the free radical polymerization of the unsaturated polyes-ter and vinyl ester resins.It is typically a single peroxide,buta combination of initiators could be used.4.Summary of Test Method4.1 Polyester or vinyl ester resin is mixed with the initia-tor(s)in a beaker causing a polymerization of the resin tooccur.Heat will accelerate the polymerization reaction.Theexotherm generated by the resin as it cures is measured usinga thermocouple.The curve is plotted and the time to reachvarious temperatures along with the peak temperature obtained(peak exotherm)is determined.The initiator normally em-ployed to generate the test results is benzoyl peroxide,althoughthe method may be used with other initiator systems.4.2 The test method is useful in providing information aboutthe heat generated during cure of the resin and the length oftime the resin remains in the liquid state prior to polymeriza-tion into solid form.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 2004.Last previous edition approved in 2004 as D7029-04.DOI:10.1520/D7029-09.2Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Significance and Use5.1 This test method is used to measure the reactivity ofdifferent lots of unsaturated polyester and vinyl ester resins.The information provided by this test can be used for assessingthe predicted performance of a resin when used in elevatedtemperature as part of the process used to convert the resin intoa finished product.5.2 The method is used in research and development bycompanies that manufacture resins and for incoming qualitycon