ASTM_D_5667_-_21.pdf

Designation:D566721Standard Test Method forRubber From Synthetic SourcesTotal and Water SolubleAsh1This standard is issued under the fixed designation D5667;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 a test method for the determi-nation of ash content in synthetic rubber.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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:2D5668 Test Methods for Rubber From Synthetic SourcesVolatile MatterPART ATOTAL ASH3.Summary of Test Method3.1 A dried sample is accurately weighed into a taredcrucible and ignited in a muffle furnace at test temperature untilall the carbonaceous material is oxidized.The crucible is thenallowed to cool in a desiccator and weighed,and the percent-age of ash is calculated.4.Significance and Use4.1 These tests are mainly intended for referee purposes butcan also be used for quality control of rubber production.4.2 The total and water soluble ash content of a rubber canaffect the properties of compounded,vulcanized rubber such aswater absorption,swell,electrical properties,etc.5.Apparatus5.1 Crucible,having a minimum volume of 50 cm3.NOTE1If water soluble ash is to be determined,use a fine-porosityfritted glass or sintered porcelain filtering crucible,placing a small amountof ashless filter paper in the bottom of the crucible in order to prevent lossof liquid pyrolysis products.5.2 Ashless Filter Paper,150 mm in diameter.5.3 Muffle Furnace,capable of being maintained at 550 625 C or 850 6 25 C,or both.5.4 Glass Stirring Rod.5.5 Rubber Policeman.5.6 Drying Oven.6.Sample Preparation6.1 Prepare the sample by drying in accordance with TestMethods D5668.7.Procedure7.1 Accurately weigh 3 to 5 g of the dried sample in thetared crucible,which has been ignited to constant weight at 5506 25 C.In the case of alum-coagulated rubbers,which tend toboil over during ashing,wrap the sample tightly in a 150-mmashless filter paper before ashing.Load the crucible with thedried sample at 300 C.Ramp up the temperature to 550 C.(Slow heating will reduce the possibility of fly loss duringburning/charring of the sample).Allow it to remain there untilthe carbonaceous material has been completely oxidized.NOTE2Caution:Do not open the furnace door for the first 30 minafter reaching test temperature.It is recommended to open for a while andclose the furnace door and continue heating the sample,to ease thecombustion process.NOTE3If fritted glass crucible is used,place the crucible in the mufflefurnace at 300 6 25 C for 30 min.Then raise the temperature to 550 625 C and heat for at least 1 h or until all the carbonaceous material has1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials and is the direct responsibility of Subcommittee D11.11on Chemical Analysis.Current edition approved Nov.1,2021.Published December 2021.Originallyapproved in 1995.Last previous edition approved in 2019 as D5667 95(2019).DOI:10.1520/D5667-21.2For 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.1?been oxidized.Reduce temperature to 300 C before removing.7.2 After the material has been completely oxidized,re-move the crucible from the furnace,cool it to room tempera-ture in the desiccator,and weigh it.If the ash line is within 3mm of the rim of the crucible,discard the ash and rerun theanalysis.7.3 Reheat the crucible and its contents for a minimum of 60min at 550 6 25 C,remove the crucible from the furnace,coolit