ASTM_D_2165_-_94_2012e1.pdf

Designation:D216594(Reapproved 2012)1Standard Test Method forpH of Aqueous Extracts of Wool and Similar Animal Fibers1This standard is issued under the fixed designation D2165;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.This standard has been approved for use by agencies of the Department of Defense.1NOTEThe terminology section was updated in July 2012.1.Scope1.1 This test method covers the determination of the pH ofaqueous extracts from wool and similar animal fibers.It isapplicable to fibers in any conditionraw wool,scoured wool,sliver,top,yarn,or fabric.1.2 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 specificprecautionary statements,see Section 11.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD2525 Practice for Sampling Wool for MoistureD4845 Terminology Relating to WoolE70 Test Method for pH of Aqueous Solutions With theGlass Electrode3.Terminology3.1 For all terminology related to D13.13,refer to Termi-nology D4845.3.1.1 The following terms are relevant to this standard:aqueous extract,pH.3.2 For all other terminology related to textiles,see Termi-nology D123.4.Summary of Test Method4.1 An extract is prepared using distilled water or 0.1 Nsodium chloride solution at the boil under reflux,or at roomtemperature with agitation.The pH of the extract is measuredelectrometrically with a glass electrode.5.Significance and Use5.1 The pH values of the extracts give an indication of theacidity or alkalinity of the fiber and its water-soluble impuri-ties.These values are useful in indicating previous processingand in anticipating subsequent performance.For particularpurposes,the pH of an extract prepared by one method may bea more informative index than another and as a consequencefour optional extraction procedures are included.5.2 This test method is not recommended for acceptancetesting because the between-laboratory precision is relativelypoor.In some cases,the purchaser and the seller may have totest a commercial shipment of one or more specific materialsby the best available method,even though the method has notbeen recommended for acceptance testing of commercialshipments.In such a case,if there is disagreement arising fromdifferences in values reported by the purchaser and the sellerwhen using this method for acceptance testing,the statisticalbias,if any,between the laboratory of the purchaser and thelaboratory of the seller should be determined,with eachcomparison being based on testing specimens randomly drawnfrom one sample of material of the type being evaluated.6.Apparatus and Materials6.1 All glassware coming in contact with the liquid shall beof a chemical-resistant glass,3in which the contacting surfaceshave been soaked for two days in 0.1 N hydrochloric acid andthen rinsed thoroughly with distilled water(see 7.1)until therinsings have a pH of 6.0 or higher.NOTE1It is desirable but not mandatory that the glassware bereserved for extraction tests only and be filled with distilled water duringstorage between tests.6.2 Apparatus for Extraction at Room Temperature:6.2.1 Erlenmeyer Flasks,250-ml,wide-mouth,withground-glass stoppers.1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.13 on Wool and Felt.Current edition approved July 1,2012.Published August 2012.Originallyapproved in 1961.Last previous edition approved in 2006 as D2165 94(2006).DOI:10.1520/D2165-94R12E01.2For 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.3Borosilicate glass has been found satisfactory.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.2.2 Laboratory Shaker or Agitator,with apparatus forattaching the flasks,holding at least three flasks,to provideagitation that will not raise the temperature more than 5.5C in2 h.6.3 Additional Equipment Needed for Extraction at TheBoil:6.3.1 Erlenmeyer Flask,500-mL,with ground-glass joint.6.3.2 Air Condenser,Glass,reflux,to fit the flask.6.3.3 Tube,to hold absorbent for acidic and basic gases.6.3.4 Glass Stopper,for flask,equipped with a stopcock andthermometer with a range from 0 to 105C.6.4 pH Meter and Glass Electrode,conforming to therequirements of Sections 5 and 6 of Test Method E70.7.Reagents7.1 Distilled Water,having a pH of between 6.2 and 7.0.Ifnot in th