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ASTM_D_1108_-_21.pdf

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1、Designation:D110821Standard Test Method forDichloromethane Solubles in Wood1,2This standard is issued under the fixed designation D1108;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

2、 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 determination of the dichlo-romethane soluble content of wood,which is a measure of thewaxes,fats,resins,oils,and similar materials.

3、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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.Spec

4、ific precautionary statements are given in 4.1.1.3 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

5、 World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Significance and Use2.1 Dichloromethane extractable content of wood is a mea-sure of substances such as waxes,fats,resins,phytosterols,andnonvolatile hydrocarbons.The amount is influenced by season-ing or drying the wood.3.Apparatu

6、s3.1 Filtering CruciblesAlundum or fritted-glass filteringcrucibles of coarse porosity shall be used.3.2 Extraction ApparatusA compact form of Soxhlet ex-traction apparatus,with ground-glass joints,is preferable.Theapparatus shall consist of the following items:3.2.1 Soxhlet Extraction Flask,having

7、a capacity of 250mL.3.2.2 Soxhlet Extraction Tube,45 to 50 mm in insidediameter,having a capacity to the top of the siphon ofapproximately 100 mL and a siphon tube approximately 55mm in height.Extraction tubes of these dimensions siphonmore rapidly than extractors with higher siphon tubes.3.2.3 Cond

8、enser,water cooled.4.Reagent4.1 Dichloromethane,98%,CH2Cl2,USP.(WarningDichloromethane causes narcosis when inhaled and can beirritating to the eyes.Proper caution should be used.)5.Test Specimen5.1 The test specimen shall consist of 2 g of air-driedsawdust that has been ground to pass a 425-m(40 me

9、sh sieve)and be retained on a 250-m(60 mesh)sieve.6.Procedure6.1 Weigh two 2-g test specimens in tared Alundum orfritted-glass crucibles.Dry one specimen in an oven for 2 h at100 to 105C;then place in a loosely stoppered weighingbottle,cool in a desiccator,and weigh.Continue the drying for1-h period

10、s until the weight is constant.Calculate the propor-tion of moisture-free sawdust in the air-dry specimen.6.2 This step must be carried out in a fume hood.Place theother specimen in a Soxhlet extraction apparatus having a taredSoxhlet extraction flask.Set a small disk of fine-mesh screenwire in the

11、top of the crucible to prevent loss of sample.Extractwith 150 mL of dichloromethane for 6 to 8 h,keeping thesolvent boiling briskly.This should provide at least six to eightsiphonings per hour.6.3 After evaporating the solvent from the extraction flask,preferably using a rotary evaporator,dry the fl

12、ask and contentsin an oven for 1 h at 100 to 105C,cool in a desiccator,andweigh.Continue the drying until there is no further loss inweight.7.Calculation and Report7.1 Report the results as percentage by weight of dichlo-romethane soluble matter in the moisture-free wood,calculatedas follows:dichlor

13、omethane soluble matter,%5W2/W1P!3100(1)where:W2=weight of dried extract(6.3),W1=weight of test specimen used in 6.2,and1This test method is under the jurisdiction of ASTM Committee D07 on Woodand is the direct responsibility of Subcommittee D07.01 on Fundamental TestMethods and Properties.Current e

14、dition approved Feb.1,2021.Published March 2021.Originallyapproved in 1950.Last previous edition approved in 2013 as D1108 96(2013).DOI:10.1520/D1108-21.2This standard was originally based upon TAPPI Standard Method T 204-os-76,which has been replaced by T 204 cm-17.Copyright ASTM International,100

15、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 Recommen

16、dations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1P=proportion of moisture-free sawdust in the air-dryspecimen 6.1.7.2 Base the results on the average of at least two determi-nations.8.Precision and Bias38.1 Values obtained in a round robin test involving fivelaboratories and two woods indicated a repeatability of 4%and a reproducibility of 21%.8.2 Bias is unknown.9.Keywords9.1 dichloromethane;woodASTM International takes no position respecting the validit

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