ASTM_D_3312_-_04_2013.pdf

Designation:D331204(Reapproved 2013)Standard Test Method forPercent Reactive Monomer in Solventless Varnishes1This standard is issued under the fixed designation D3312;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 the determination of the percentof volatile reactive monomer having a vapor pressure exceed-ing 13.3 Pa(0.1 Torr)at 25C in an uncatalyzed solventlessvarnish.Experience has shown this method does not accuratelydetermine percent reactive monomer when the vapor pressureis less than 13.3 Pa(0.1 Torr).1.2 The values stated in SI units are the standard.The valuesgiven in parentheses are for information only.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.For a specificprecaution,see Section 5.NOTE1There is no similar or equivalent ISO/IEC standard.2.Referenced Documents2.1 ASTM Standards:2D1711 Terminology Relating to Electrical InsulationD5423 Specification for Forced-Convection Laboratory Ov-ens for Evaluation of Electrical Insulation3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 reactive monomer,nin solventless electrical varnish,a substance,that,when added to a resin,will combinechemically with that resin under specified conditions.3.2 See Terminology D1711 for definitions of other termsrelating to electrical insulation.4.Significance and Use4.1 The percent of reactive monomer in solventless var-nishes will affect the viscosity,the handling,and the processingproperties of the uncured resin.The percent of reactivemonomer will possibly affect the degree of hardness andshrinkage which in turn will affect the physical and electricalproperties of the cured resin.5.Safety Precautions5.1 It is unsafe to use varnish at temperatures above theflash point without adequate ventilation,especially if thepossibility exists that flames or sparks are present.Storevarnish in sealed containers.6.Apparatus6.1 Balance,capable of weighing to nearest 0.0001 g.6.2 ThermometerA glass thermometer having a rangefrom 0 to 200C(30 to 400F)and accurate within 61C(62F).6.3 OvenA forced-draft constant-temperature oven con-forming to Specification D5423,Type II.6.4 Bottle and Drying DishesA stoppered bottle andflat-bottom aluminum drying dish.having an inside diameter ofapproximately 70 mm(234in.)and a depth of 8 mm(516in.).6.5 DesiccatorAsuitable desiccator containing anhydrouscalcium chloride(CaCl2).7.Test Specimens7.1 Preparing SpecimensPlace a portion of the uncata-lyzed solventless varnish in a stoppered bottle and weigh.Transfer a specimen weighing between 0.2 and 0.3 g from theweighed stoppered bottle to a weighed drying dish,which hasbeen previously heated for 30 min at 150C(300F)and cooledin a desiccator.Weigh the stoppered bottle with the remainingcontents again.Determine the exact weight of the specimentransferred to the drying dish by the difference in weight of thestoppered bottle.Prepare two specimens from the contents ofthe stoppered bottle.8.Procedure8.1 Dilution of SpecimensAdd 5 6 1 mL of methylisobutyl ketone(MIBK)to each specimen in the drying dish.1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.01 on Electrical Insulating Varnishes,Powders and Encapsulat-ing Compounds.Current edition approved April 1,2013.Published April 2013.Originallyapproved in 1974.Last previous edition approved in 2009 as D3312 04(2009).DOI:10.1520/D3312-04R13.2For 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 Mix the specimen and the MIBK by moving the drying dishesin a circular direction.Mixing on a hot plate at temperaturesbelow 65C(150F)is permissible.Take care to prevent anyloss of solvent or specimen by spillage.8.2 Drying SpecimensPlace the specimens in constant-temperature oven which has been stabilized at 150C(300F)within 15 min after mixing.Keep the specimens in the 150C(300F)oven for 15 min.8.3 Weighing Dried SpecimensAt the termination of the15-min heating period,remove the specimens to a desiccatorand cool to room temperature.Weigh each specimen immedi-ately upon removal from the desiccator.9.Calculation9.1 Calculate the percentage of monomer by weight as aratio of the weight loss of the dried