ASTM_D_4572_-_21.pdf

Designation:D457221Standard Test Method forRubber ChemicalsWet Sieve Analysis of Sulfur1This standard is issued under the fixed designation D4572;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 evaluation of the particlesize distribution of the coarse fraction of sulfur.It is limited tothe measurement of those particles greater than 45 m(No.325sieve).1.2 UnitsThe values stated in SI units are to be regardedas the standard.No other units of measurement are included inthis 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesE11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.Significance and Use3.1 This test method is used to evaluate sulfur for suitabilityas a rubber vulcanizing agent.Sulfur particles must be signifi-cantly small enough to dissolve in rubber during cure andproduce a uniform network of cross-links.This test method isused as a quality control method to ensure that no excessivelylarge sulfur particles are present and to see if the productfollows a typical pattern of size distribution.3.2 This procedure is necessary when problems of the sulfurcaking occur with the use of the dry sieving procedure forparticle size.4.Apparatus4.1 Standard Sieves,stainless steel,76 mm diameter con-taining selected stainless steel wire cloth in the range of 45 to250 m mesh count,conforming to Specification E11.Acascade stack/support is recommended to keep cascade sievesin place during analysis.4.2 No.6 Stiff Bristle Artist Brush,having 10 to 15 mm longbristles.4.3 Balance,with a minimum capacity of 150 g sensitive to0.001 g.4.4 Oven,circulating air type,controlled to 70 6 2C.4.5 Beaker,250 cm3.5.Materials5.1 Liquid Detergent.6.Procedure6.1 Weigh 10.0 g of the sulfur sample into a 250-cm3beaker.Wet the sulfur with 25 cm3of water.Mix thoroughlywith a glass stirring rod to guarantee wetting all the sulfur.NOTE1A1%solution of a liquid detergent may be used if the sulfursample does not wet out properly.6.2 Weigh each cleaned and dried sieve to the nearest 0.001g.Assemble preweighed stainless steel sieves in order ofdescending fineness with the coarsest screen on top.Carefullytransfer the wetted sulfur to top screen using additional waterto wash all of the sulfur out of the beaker.Wash the sulfurthrough the top sieve with a gentle stream of water from anozzle and add additional detergent(see 5.1)as needed.Tap orvibrate the screen while washing(not needed if using a cascadestack).Finally,break up all agglomerated sulfur particles usingthe brush.Clean sulfur from the bristles of the brush usingwash water.Be careful that the wash water does not back up onthe finer sieves causing the sulfur slurry to overflow the sievesides.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials and is the direct responsibility of Subcommittee D11.20on Compounding Materials and Procedures.Current edition approved Nov.1,2021.Published November 2021.Originallyapproved in 1986.Last previous edition approved in 2017 as D4572 89(2017).DOI:10.1520/D4572-21.2For 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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.16.3 Remove the top sieve after water passing through sieveis free of any sulfur particles.Wash off any residual sulfurslurry on the underside of the sieve so that it passes through thenext sieve in the cascade.Repeat the washing proceduredescribed in 6.2 ensuring total transport of the fine sulfu