ASTM_D_3346_-_12.pdf

Designation:D334612Standard Test Methods forRubber PropertyProcessability of Emulsion SBR(Styrene-Butadiene Rubber)With the Mooney Viscometer(DeltaMooney)1This standard is issued under the fixed designation D3346;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 These test methods explain the use of the shearing diskviscometer to obtain an indication of the processability ofnon-pigmented emulsion styrene-butadiene rubbers(SBR).They may also be used to separate those polymers that are easyto process from those that are difficult to process within a groupof polymers of the same type.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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 ASTM Standards:2D1646 TestMethodsforRubberViscosity,StressRelaxation,andPre-VulcanizationCharacteristics(Mooney Viscometer)D3182 Practice for RubberMaterials,Equipment,and Pro-cedures for Mixing Standard Compounds and PreparingStandard Vulcanized SheetsD3896 Practice for Rubber From Synthetic SourcesSamplingD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustries3.Terminology3.1 Definitions:3.1.1 Mooney,nthe difference in Mooney viscosityrecorded for a rubber at specified times during a test.3.1.2 Mooney viscosity,nmeasure of the viscosity of arubber or rubber compound determined in a Mooney shearingdisk viscometer;viscosity is indicated by the torque required torotate a disk embedded in a rubber specimen and enclosed inthe die cavity under specified conditions.4.Summary of Test Methods4.1 In Test Method A,the difference in Mooney viscosity at100C(212F)is determined at two specified times.Eithermassed or unmassed samples may be used.4.2 In Test Method B,the Mooney viscosity difference forunmassed samples is determined between the minimum re-corded directly after starting the rotor and the subsequentmaximum(see Fig.1).5.Significance and Use5.1 These empirical tests have been found to be suitable forranking a series of unpigmented emulsion SBR in order ofprocessability.They may also be used for comparing a produc-tion lot with a standard of known processability characteristics.The difference between Mooney viscosities at two specifiedtimes will rank those emulsion SBR polymers that differappreciably in this property according to their processability.The actual values obtained for a given polymer depend onwhether or not the sample was massed,and may vary betweenlaboratories or with the type of machine used,and with thespecified times at which Mooney viscosity values were taken.6.Apparatus6.1 The apparatus shall be in accordance with theApparatussection of Test Methods D1646.6.2 The large rotor shall be used.7.Sample Preparation7.1 For sampling procedure,refer to Practice D3896.7.2 Condition the sample until it has reached room tempera-ture of 23 6 3C(73 6 5.4F)throughout.1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.12 on ProcessabilityTests.Current edition approved May 1,2012.Published June 2012.Originallyapproved in 1974.Last previous edition approved in 2007 as D3346 07.DOI:10.1520/D3346-12.2For 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 7.3 The tests can be performed using specimens taken fromeither massed or unmassed samples.7.3.1 To mass a sample,pass 250 6 5 g of the samplebetween the rolls of the standard laboratory mill described inPractice D3182.The mill shall have a roll temperature of 50 65C(122 6 9F)and a distance between the rolls of 1.4 6 0.1mm(0.055 6 0.005 in.)as determined by a lead slug.Immediately fold the sample in half and insert the folded endinto the mill for a second pass.Repeat this procedure until atotal of nine passes have been completed.Immediately insertthe rubber without folding into the mill for a tenth pass.Do notallow the sample to rest between passes or to band on the millrolls at any time.7.3.2 Allow the massed samples to rest at room temperaturefor at least 30 min before preparing the specimens andmeasuring their viscosity.7.4 Condition unmassed samples until they have attainedroom temper