1、Designation: C613M 97 (Reapproved 2008)1Standard Test Method forConstituent Content of Composite Prepreg by SoxhletExtraction1This standard is issued under the fixed designation C613M; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, 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.1NOTEThis standard was corrected to
3、 a single-designation standard editorially in October 2013.1. Scope1.1 This test method covers a Soxhlet extraction procedureto determine the matrix content, reinforcement content, andfiller content of composite material prepreg. Volatiles content,if appropriate, and required, is determined by means
4、 of TestMethod D3530/D3530M.1.1.1 The reinforcement and filler must be substantiallyinsoluble in the selected extraction reagent and any filler mustbe capable of being separated from the reinforcement byfiltering the extraction residue.1.1.2 Reinforcement and filler content test results are totalrei
5、nforcement content and total filler content; hybrid materialsystems with more than one type of either reinforcement orfiller cannot be distinguished.1.2 This test method focuses on thermosetting matrix ma-terial systems for which the matrix may be extracted by anorganic solvent. However, other, unsp
6、ecified, reagents may beused with this test method to extract other matrix material typesfor the same purposes.1.3 Alternate techniques for determining matrix and rein-forcement content include Test Methods D3171 (matrixdigestion), D2584 (matrix burn-off/ignition), and D3529/D3529M (matrix dissoluti
7、on). Test Method D2584 is preferredfor reinforcement materials, such as glass, quartz, or silica, thatare unaffected by high-temperature environments.1.4 The values stated in SI units are to be regarded asstandard.1.5 This standard does not purport to address all of thesafety concerns, if any, assoc
8、iated 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. Specific precau-tionary statements are given in Section 9 and 7.2.3 and 8.2.1.2. Referenced Document
9、s2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD2584 Test Method for Ignition Loss of Cured ReinforcedResinsD3171 Test Methods for Constituent Content of CompositeMaterialsD3529/D3529M Test Method for Matrix Solids Content andMatrix Content of Composite PrepregD3530/D3530M Test Method for
10、 Volatiles Content of Com-posite Material PrepregD3878 Terminology for Composite MaterialsE122 Practice for Calculating Sample Size to Estimate, WithSpecified Precision, the Average for a Characteristic of aLot or ProcessE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 T
11、erminology Relating to Quality and StatisticsE1309 Guide for Identification of Fiber-ReinforcedPolymer-Matrix Composite Materials in DatabasesE1471 Guide for Identification of Fibers, Fillers, and CoreMaterials in Computerized Material Property Databases2.2 NFPA Standard:NFPA 86 Standard for Ovens a
12、nd Furnaces33. Terminology3.1 DefinitionsTerminology D3878 defines terms relatingto composite materials. Terminology D883 defines termsrelating to plastics. Terminology E456 and Practice E177define terms relating to statistics. In the event of a conflict1This test method is under the jurisdiction of
13、 ASTM Committee D30 onComposite Materialsand is the direct responsibility of Subcommittee D30.03 onConstituent/Precursor Properties.Current edition approved April 1, 2008. Published April 2008. Originallyapproved in 1967. Last previous edition approved in 2008 as C613/C613M 97(2008)1. DOI: 10.1520/C
14、0613M-97R08E01.2For 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.3Available from National Fire Protection Assoc
15、iation (NFPA), 1 BatterymarchPark, Quincy, MA 02269-9101.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1between terms, Terminology D3878 shall have precedenceover the other documents.3.1.1 matrix content, nthe amount of matrix presen
16、t in acomposite or prepreg expressed either as percent by weight orpercent by volume. For polymer matrix composites this is resincontent. D38783.1.2 prepreg, nthe admixture of fibrous reinforcementand polymeric matrix used to fabricate composite materials. Itsform may be sheet, tape, or tow. For the
17、rmosetting matrices ithas been partially cured to a controlled viscosity called “Bstage”. D38783.1.3 resin content, nsee matrix content. D38783.1.4 sample, na small part or portion of a material orproduct intended to be representative of the whole. D8833.1.5 test result, nthe value obtained for a gi
18、ven propertyfrom one test unit.43.1.5.1 DiscussionA test result may be a single observa-tion or a combination of a number of observations when two ormore test specimens are measured for each test.3.1.6 test specimen, na test unit or portion of a test unitupon which a single or multiple observation i
19、s to be made.43.1.7 test unit, na unit or portion of a material that issufficient to obtain a test result(s) for the property or propertiesto be measured.3.1.7.1 DiscussionA test unit may be a subunit of aprimary (first stage) sampling unit or it may be a subunit of acomposite of primary sampling un
20、its or of increments fromthese primary sampling units.3.2 Definitions of Terms Specific to This Standard:3.2.1 dry resin content, nprepreg resin content calculatedby subtracting the average mass loss due to volatiles from theinitial test specimen mass.3.2.2 filler content, nthe amount of filler pres
21、ent in aprepreg or composite expressed either as percent by weight orpercent by volume.3.2.2.1 DiscussionIn this test method the reinforcement isseparated from the remainder of the material, which includesthe matrix and the filler. If the filler is not then separated fromthe matrix to determine the
22、proportion of each, then the fillercontent is included in the matrix content.3.2.3 reinforcement content, nthe amount of reinforce-ment present in a composite or prepreg expressed either aspercent by weight or percent by volume. This is sometimesstated as a fraction, that is, reinforcement volume fr
23、action.3.2.4 replicate, na test specimen tested under nominallyidentical conditions as other test specimens from the samesample.3.2.5 volatiles content, nthe amount of volatiles present ina prepreg expressed as percent by weight.3.2.6 wet resin content, nprepreg resin content determinedby considerin
24、g volatiles as part of the resin mass.3.3 Symbols:3.3.1 Ainitial mass of dry reinforcement during a reagentexposure evaluation.3.3.2 Bfinal mass of dry reinforcement during a reagentexposure evaluation.3.3.3 cpercent reinforcement mass change due to reagentexposure.3.3.4 CVcoefficient of variation s
25、tatistic of a samplepopulation for a given property.3.3.5 Maadditional mass of filler in the test specimen.3.3.6 Memass of the test specimen extraction residue.3.3.7 Miinitial mass of the test specimen.3.3.8 Mrmass of reinforcement in the test specimen.3.3.9 nnumber of replicates in the sample popul
26、ation.3.3.10 sn1standard deviation statistic of a sample popu-lation for a given property.3.3.11 Wfweight percent of filler in prepreg.3.3.12 Wmweight percent of matrix in prepreg.3.3.13 Wrweight percent of reinforcement in prepreg.3.3.14 xitest result for an individual test specimen fromthe sample
27、population for a given property.3.3.15 xaverage value of a sample population for a givenproperty.4. Summary of Test Method4.1 The exposed surface area of the prepreg material testspecimen is increased by cutting the test specimen into smallerpieces. The test specimen is weighed and the matrix materi
28、alremoved by means of Soxhlet extraction. The extracted residueis dried and weighed. If a filler is present in the residue, inaddition to reinforcement, the two components are separatedby filtering the residue. From mass measurements of the initialtest specimen, and of the residue taken at various s
29、tages in theprocess, the matrix content, reinforcement content, and fillercontent are calculated and reported in weight percent.4.1.1 Soxhlet ProcessWhile described in detail in com-mon quantitative chemical analysis textbooks, the Soxhletprocess is summarized as follows. The test specimen is loaded
30、into a filtering extraction thimble, which is placed into theextraction chamber of a Soxhlet extraction assembly (see Fig.1) containing an appropriate extraction reagent. The porousthimble allows the liquid extraction reagent to pass whileretaining the test specimen. Freshly distilled liquid reagent
31、enters from the top of the extraction chamber, filling it until theliquid reaches the highest level of the reagent-return tube. Atthis moment the tube operates as a siphon, draining theextraction chamber completely as it returns the liquid reagentand any extracted material to a reservoir beneath the
32、 extractionchamber. The heated reservoir boils the reagent, the vapor ofwhich is led to a condenser placed above the extractionchamber. The distilled condensate then drips down into thethimble, starting once again the process of filling the extractionchamber. The Soxhlet operation is not a continuou
33、s operation,but rather a sequence of fillings and siphonings, each cycle ofwhich is called a reflux change. The heat input and reagentvolume are adjusted to cause the boiling reagent to return to the4See Form and Style for ASTM Standards.C613M 97 (2008)12extraction flask from the condenser at 3 to 1
34、0 reflux changesper hour, with the extraction continuing for a minimum of 4 hor 20 reflux changes, whichever comes first.4.1.2 Volatiles ContentVolatiles content is primarily ap-plicable to thermosetting materials, and, if required, is deter-mined by Test Method D3530/D3530M. Volatiles contentdeterm
35、ination requires different test specimens than those usedin the extraction process, since the process of determiningvolatiles content renders thermosetting material specimensunsuitable for subsequent organic solvent extraction.5. Significance and Use5.1 The prepreg volatiles content, matrix content,
36、 reinforce-ment content, and filler content of composite prepreg materialsare used to control material manufacture and subsequentfabrication processes, and are key parameters in the specifica-tion and production of such materials, as well as in thefabrication of products made with such materials.5.2
37、 The extraction products resulting from this test method(the extract, the residue, or both) can be analyzed to assesschemical composition and degree of purity.6. Interferences6.1 Extent of Cure in Thermosetting SystemsThe effi-ciency of extraction for thermosetting matrix materials isdirectly relate
38、d to the extent of cure of the resin system. Resinsthat have started to cross-link (such as B-staged resins) will beincreasingly more difficult to extract as the cure advances. Thistest method may not be appropriate for such materials; TestMethods D3171 or D2584 may be better test method choices.6.2
39、 Reagent SelectionThe proper reagent, in a suitablequantity, must be selected for the constituents under test. Thereagents listed in Section 8 are provided for consideration,particularly with regard to thermosetting materials, but cannotbe assured to perform well on all material systems within thesc
40、ope of this test method.6.3 Thimble ContaminationIf the extract is to undergofurther analysis, the thimble must be clean to avoid a signifi-cant source of contamination.6.4 Reinforcement Mass Change As a Result of ReagentThe calculations of this test method assume that the reinforce-ment mass (or fi
41、ller, if filler content is being determined) is notsignificantly affected (whether mass increase or mass loss) byexposure to the reagent. Small, consistent changes in thereinforcement mass caused by exposure to the reagent can becorrected by the process described in 14.4.5. The resultingcorrection m
42、ay be used if this change is sufficiently reproduc-ible under the conditions of the test, and if this change has thesame value for the reinforcement alone as for the reinforcementin the matrix. Otherwise, a different reagent, or another testmethod, must be selected.7. Apparatus7.1 General Requiremen
43、ts:7.1.1 Container VolumeA suggested volume is shown foreach container. However, other sizes may be required depend-ing upon the test specimen size, the amount of reagent neededto complete the extraction process, and the relative sizes ofrelated equipment.7.1.2 Thermal ShockLaboratory equipment that
44、 is sub-jected to non-ambient temperatures (hot or cold) shall be oftempered-glass or PTFE materials.7.1.3 Post-Test Elemental AnalysisIf a post-test elementalanalysis of the extract or residue is to be performed, laboratoryequipment contacting the test specimen shall be constructed ofPTFE and test
45、specimen cutting shall be limited to tools that donot leave an elemental trace.7.2 General Equipment:7.2.1 Analytical BalanceThe analytical balance shall becapable of reading to within 60.1 mg.7.2.2 Muffle FurnaceThe muffle furnace used to conditionglass extraction thimbles shall be capable of maint
46、aining atemperature of 510 6 15C.7.2.3 Air-Circulating Drying OvenThe drying oven shallbe capable of maintaining a temperature of 163 6 3C.(WarningFor safety purposes listed in NFPA86, take care tolimit volatile concentration in the oven by controlling samplequantity, temperature, and ventilation.)7
47、.2.4 DesiccatorThe desiccator shall be capable of con-taining the required test specimens.7.3 Extraction Assembly:7.3.1 Extraction ThimblesThe extraction thimbles shall bedeep, narrow filtering cups, of either borosilicate glass in anappropriate pore size, or fat-extracted cellulose paper, suitablef
48、or use in the extraction chamber.7.3.2 Hot PlateThe hot plate shall have adjustable con-trols suitable for heating the reagent within the reservoir flaskto 260C and shall be capable of controlling the requiredreagent temperature within 615C.7.3.3 Reservoir FlaskThe reservoir flask shall be of boro-s
49、ilicate glass, of suitable volume (125 mL is suggested) for thereagent quantity and extraction chamber volume, and shallhave a ground tapered joint capable of connection with theremainder of the assembly.7.3.4 Soxhlet Extraction ChamberThe extraction chambershall be of borosilicate glass, with an automatic recyclingsiphon that recycles at a suitable liquid volume (50 mL isFIG. 1 Schematic of Soxhlet Extraction ApparatusC613M 97 (2008)13suggested), and with a ground tapered joint at each end capableof connecting with the
