1、Designation:D778 97(Reapproved 2007)An American National StandardStandard Test Methods forHydrogen Ion Concentration(pH)of Paper Extracts(Hot-Extraction and Cold-Extraction Procedures)1This standard is issued under the fixed designation D778;the number immediately following the designation indicates
2、 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 cover two procedures for determi-na
3、tion of the hydrogen ion concentration,expressed in terms ofpH,of an aqueous extract of paper.1.2 These test methods may be applied to writing,printing,and sized industrial papers.1.3 These test methods are not intended to be used fordetermination of pH of insulating papers,for that see TestMethods
4、D202.1.4 The test methods appear as follows:SectionTest Method ApH of Paper(Unfiltered Extract)AfterExtraction for 1 h in Cold(25 6 5C)Water11.1Test Method BpH of Paper(Unfiltered Extract)AfterExtraction for 1 h in Boiling Water11.21.5 Specifications may be based on Test Method A or TestMethod B,or
5、both.1.6 Where a specification or specific instructions or agree-ment to use only one of these test methods is absent,determinepH using both procedures,and interpret results based onSection 12.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It i
6、s 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:2D202 Test Methods for Sampling and Testing UntreatedPaper Used for Electrical Insul
7、ationD585 Practice for Sampling and Accepting a Single Lot ofPaper,Paperboard,Fiberboard,and Related ProductD1193 Specification for Reagent WaterD1293 Test Methods for pH of WaterD1968 Terminology Relating to Paper and Paper ProductsE70 Test Method for pH of Aqueous Solutions With theGlass Electrode
8、E122 Practice for Calculating Sample Size to Estimate,With Specified Precision,the Average for a Characteristicof a Lot or Process3.Terminology3.1 Definitions shall be in accordance with TerminologyD1968 and the Dictionary of Paper.34.Summary of Test Methods4.1 Test Method A consists of the extracti
9、on of a 1-g testspecimen in 70 mL of cold distilled water(25 6 5C)for 1 h,and determination of pH without filtration using a commercialpH meter.4.2 Test Method B consists of the extraction of a 1-g testspecimen in 70 mL of boiling distilled water for 1 h,followedby cooling of the extract and determi
10、nation of the pH withoutfiltration using a commercial pH meter.5.Significance and Use5.1 The acidity or alkalinity of a paper sample extract isimportant because of the effect of paper acidity or paperalkalinity on the permanence of the paper.Although acidity oralkalinity may be determined by titrati
11、on the pH is often moreindicative of the stability of paper than is the total acidity oralkalinity.6.Apparatus6.1 pH MeterUse a pH meter of Type II or Type III asspecified in Test Methods D1293.In general terms this is a pHmeter accurate to 0.01 pH units with temperature compensationsuitable for mak
12、ing pH measurements over the 0 to 14-pHrange.6.2 Reflux condensers,preferably water cooled,West orAllihn Type,with 300-mm jackets,standard taper inner joints1These test methods are under the jurisdiction of ASTM Committee D06 onPaper and Paper Products and are the direct responsibility of Subcommitt
13、ee D06.92on Standard Documents Relating to Paper and Paper Products.Current edition approved Dec.1,2007.Published December 2007.Originallyapproved in 1944.Last previous edition approved in 2002 as D778 97(2002).DOI:10.1520/D0778-97R07.2For referenced ASTM standards,visit the ASTM website,www.astm.or
14、g,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from Technical Association of the Pulp and Paper Industry(TAPPI),15 Technology Parkway South,Norcross,GA 30092,http:/www
15、.tappi.org.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.NOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest information.and drip tips;or air
16、condensers,10-mm diameter and 1000 mmlong with ST inner joints and drip tips,ST joints to fit the flasks(required on hot-extraction procedure,only).7.Reagents7.1 Distilled WaterThe distilled water used in these testmethods must comply with Type II or Type III reagent water asspecified in Specification D1193.7.2 Standard Buffer Solutions:7.2.1 If buffer solutions are prepared in the laboratory,theirpreparation and corporation must comply with applicablesections of Test Method E70 or Test Methods
