1、Designation: D2402 07 (Reapproved 2018)Standard Test Method forWater Retention of Textile Fibers (Centrifuge Procedure)1This standard is issued under the fixed designation D2402; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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 the measurement of waterretention of man-made and natural fibers as staple, tow, orfil
3、ament and spun yarns. It is intended to give a measure of theamount of water which cannot be removed from thoroughlywetted fiber solely by mechanical means as applied by cen-trifugal force (see 3.2).1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its
4、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.For specific precautionary statements, see Section 9.1.3 This international standard was developed i
5、n 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
6、.1 ASTM Standards:2D123 Terminology Relating to TextilesD629 Test Methods for Quantitative Analysis of TextilesD2258/D2258M Practice for Sampling Yarn for TestingD3333 Practice for Sampling Manufactured Staple Fibers,Sliver, or Tow for TestingD4849 Terminology Related to Yarns and Fibers3. Terminolo
7、gy3.1 For all terminology relating to D13.58, Yarns andFibers, refer to Terminology D4849.3.1.1 The following terms are relevant to this standard:moisture pick-up, water retention.3.2 For all other terminology related to textiles, refer toTerminology D123.4. Summary of Test Method4.1 A specimen is t
8、horoughly wetted-out by immersion,centrifuged for 5 min at an acceleration of 9800 m/s2andweighed wet. Then, the wet specimen is dried and reweighed.Water retention is calculated and reported as a percentage ofthe dry mass.5. Significance and Use5.1 This test method for testing for water retention o
9、f fibersafter centrifuging is not recommended for acceptance testing ofcommercial shipments because the test is more appropriate fordevelopment and research. However, if the test is to be used foracceptance testing, comparative tests as described in 5.1.1 areadvised.5.1.1 In the case of a dispute ar
10、ising from differences inreported test results using Test Method D2402 for acceptancetesting of commercial shipments, the purchaser and the sup-plier should conduct comparative tests to determine if statisti-cal biases exist between their laboratories. As a minimum, thetwo parties should take a grou
11、p of test specimens that are ashomogeneous as possible and that are from a lot of material ofthe type in question. The test specimens should then berandomly assigned in equal numbers to each laboratory fortesting. The average results from the two laboratories should becompared using the Students t-t
12、est for unpaired data with anacceptable probability level chosen by the two parties whiledesigning the test program. If the analysis shows a bias, itscause must be found and corrected, or the purchaser andsupplier must agree to interpret future test data with consider-ation for the known bias.5.2 Th
13、e amount of water retained by a fiber mass increaseswith an increase in the hydrophilic tendency of the fiber. Thusthe data obtained can be used to indicate the following:5.2.1 Differences in water retention between the variousman-made and natural fibers,5.2.2 Degree of cross-linking in cellulosic f
14、ibers,5.2.3 Damage incurred by wool and silk fibers due toalkaline processing, and5.2.4 Persistence of water-repellent treatments.1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Current edition a
15、pproved July 1, 2018. Published July 2018. Originally approvedin 1965T Last previous edition approved in 2012 as D2402 07 (2012). DOI:10.1520/D2402-07R18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMS
16、tandards 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 princi
17、ples 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.16. Apparatus6.1 Stationary Coarse Comb3, approximately 63 mm longand having
18、needles approximately 12.5 mm long and spaced 19needles to the 10 mm, or6.2 Hand Cards.6.3 Centrifuge,4with trunnions capable of holding at least 2tube assemblies. The centrifuge must be capable of operatingto develop an angular speed that will produce a radial accel-eration of 9800 m/s2(1000 g) on
19、the specimen within 5 min.6.4 Tube Assemblies, each consisting of a 15-mL,polypropylene, centrifuge tube with draining holes, shell andsupport wire (see Fig. 1).6.5 Timer, suitable for controlling immersion time andcentrifuge time to 61s.6.6 Balance, with sensitivity of 0.5 mg and a capacity of2000
20、g.6.7 Weighing Containers, air-tight, large enough to hold aspecimen basket.6.8 Oven, convection type, maintained at 105 to 110C.6.9 Desiccator, with an efficient desiccant such as anhy-drous silica gel, anhydrous calcium sulfate, or phosphorouspentoxide.6.10 Bell Jar, optional, see 10.5.1.7. Hazard
21、7.1 Sodium hydroxide (see Note 4) is a strong base andmust be handled with appropriate safety precautions. Refer tothe manufacturers material safety data sheet information.8. Sampling8.1 Lot SampleAs a lot sample for acceptance testing, takeat random the number of shipping containers directed in the
22、applicable material specification or other agreement betweenthe purchaser and supplier, such as an agreement to usePractice D3333 for staple fiber, sliver, top or tow, or to usePractice D2258/D2258M for yarn. Consider the shippingcontainers to be the primary sampling units.NOTE 1An adequate specific
23、ation or other agreement between thepurchaser and supplier requires taking into account the variability betweenshipping containers, between laboratory samples within the shippingcontainer, and between test specimens within a laboratory sample, toprovide a sampling plan with a meaningful producers ri
24、sk, consumersrisk, acceptable quality level, and limiting quality level.8.2 Laboratory SampleAs a laboratory sample for accep-tance testing, proceed as follows:8.2.1 For Staple FiberSystematically take five laboratorysample subunits from each bale in the lot sample as directed inPractice D3333.8.2.2
25、 For Tow and Sliver (or Top)From each shippingcontainer in the lot sample, take at least a metre, or yard, ofmaterial from the leading end of the textile strand that has aclean uniform appearance. If the shipping container has mul-tiple packages, take one package drawn at random from thecontainer fo
26、r that laboratory sample.8.2.3 For Yarn in CasesTake ten yarn packages as di-rected in Practice D2258/D2258M. Remove enough traversesof yarn to obtain a surface free of visible damage or soil, andthen remove at least a gram of yarn for the laboratory samplefrom each laboratory sampling unit.8.2.4 Fo
27、r Yarn on BeamsSample as agreed upon betweenthe purchaser and supplier.8.3 Test SpecimensTest two 0.5 g specimens from eachlaboratory sampling unit, preferably from different sections ofthe laboratory sample units.9. Conditioning9.1 Specimens may be tested without any conditioning.10. Specimen Prepa
28、ration10.1 Foreign Matter and Extractable MatterIf the labo-ratory sample units contain foreign matter, remove the latter bymechanical means (such as hand carding). For samples con-taining nonfibrous natural constituents of the fiber (such as oils3Combs meeting these requirements may be obtained fro
29、m Alfred Suter Co.,Inc., Prel Plaza, Orangeburg, NY 10962.4A clinical safety-head centrifuge is satisfactory for this procedure.FIG. 1 Cross-section View of Centrifuge Tube AssemblyD2402 07 (2018)2and waxes) or substances added by the manufacturer (such asfinish, starch, soaps, waxes, etc.), extract
30、 portions by one ormore of the treatments prescribed in Section 8 on NonfibrousMaterials of Test Methods D629. Use air-drying instead ofoven-drying.NOTE 2In general, avoid use of temperatures above 50C since suchtemperatures often affect fiber structure and, thus, water retention.10.2 Staple:10.2.1
31、Prepare composites of each the laboratory sampleunits by taking about 0.1 g portions from different areas of eachof the five laboratory subunits for 0.5 g specimens.10.2.2 Using a stationary comb or hand cards, carefullyparallelize the fibers.10.2.3 Prepare 0.5 6 0.05 g specimens of the carded fiber
32、and tie the bundles in their midsections, using some of thesame fiber or a small wire (for example 30-gage Nichrome).(See 11.3.) Form a loop with the tying fibers, or hook or loopwith the wire, for suspending the bundle from the support wireof the centrifuge tube. Remove any loose fibers from thebun
33、dle before weighing.NOTE 3If wire is used, it must be weighed as part of the weighingcontainer tare mass (11.3) before use in fastening the specimen bundle.10.3 Tow or Sliver (Top):10.3.1 For tow, cut sections, 500 to 1000 mm in length,from different areas of a laboratory tow sample and split off 0.
34、56 0.05 g specimens from the side. Fasten the specimen asdirected in 10.2.3.10.3.2 For sliver (top), draft short segments from differentsections of a laboratory sample and split off 0.5 6 0.05 gspecimens from the side. Fasten the specimen as directed in10.2.3.10.4 Yarn:10.4.1 Prepare two 0.5 g skein
35、s by winding an appropriatenumber of turns on a tapered mandrel (Note 4) from differentsections of each of the laboratory sample units.NOTE 4A No. 4 rubber stopper, which has been boiled in sodiumhydroxide solution to remove sulfur, has been found to be a convenientsize (see 7.1).10.4.2 Tie each of
36、the skeins in two places about half thecircumfence apart using yarn of the same supply.11. Procedure11.1 Make all weighings in the standard atmosphere fortesting textiles, which is 21 6 1C (70 6 2F) and 65 6 2%relative humidity.11.2 Calculate the angular speed required to produce aradial acceleratio
37、n of 9800 m/s2(1000 g), using Eq 1:n 5 8.943 310631/r!1/2(1)where:n = revolutions per minute, andr = radial distance of the fiber mass from the center ofrotation, mm.11.3 Weigh dry, identified weighing containers and coversto the nearest 0.001 g. If wire is needed to tie specimen bundles(10.2.3), in
38、clude the wire in the individual container taremasses. Record each tare mass, T.11.4 Immerse each prepared specimen in an identifiedbeaker of distilled water at room temperature for 5 min, orlonger if needed to completely wet out the specimen. Recordthe immersion time.11.4.1 If air is entrapped in t
39、he specimen, remove the airbubbles either by (1) mechanical agitation, or (2) covering thebeaker and specimen with a bell jar and lowering the airpressure until the water boils.11.5 At the end of the immersion period, remove thespecimen from the distilled water. Attach the specimen to thetube assemb
40、ly support wire through the yarn skein, or fiber orwire loop or wire hook of the fiber bundle.11.6 Suspend the specimen in an identified centrifuge tubeby the support wire.NOTE 5Dissection needles may be useful in inserting the specimen inthe tube.11.7 Transfer the tubes to the centrifuge. Distribut
41、e thetubes evenly spaced about the centrifuge, filling in with emptytubes as needed to balance the load.11.8 Start the centrifuge and spin for 5 min 6 5 s, includingacceleration time.11.9 At the end of the spin, stop the centrifuge quickly andimmediately transfer the specimens back to their individu
42、alweighing containers and put the covers on.11.10 Weigh the containers with the specimens, and wires ifused, to the nearest 0.001 g. Record each wet mass, M.11.11 Place the wet specimens, weighing containers, covers,and wires, if any, in the oven and dry them at 105 to 110C forabout 1.5 h.11.12 Tran
43、sfer the dry specimens with their weighingcontainers, covers, and wires, if any, to the desiccator and cool.11.13 Weigh the dried specimens with their weighingcontainers, covers, and wires, if any, to the nearest 0.001 g.Record these masses as dry mass, D.12. Calculation12.1 Calculate the water rete
44、ntion, to the nearest 0.1 %,using Eq 2:R 5 100M 2 D!/D 2 T! (2)where:R = water retention, %,M = mass of moist specimen with its tare mass (11.10), g,D = mass of dried specimen with its tare mass (11.13), g,andT = mass of the tare (see 11.3).12.2 Calculate the average percent water retention for thet
45、wo specimens for each laboratory sampling unit, and theaverage for the lot.12.3 If requested, calculate the standard deviation, or coef-ficient of variation, or both, for each laboratory sampling unitand for the lot.D2402 07 (2018)313. Report13.1 State that the samples were tested as described in Te
46、stMethod D2402. Describe the material(s) and product(s)sampled, and the method of sampling used.13.2 Report the following information:13.2.1 The individual and average percent water retentionfor each laboratory sampling unit,13.2.2 The average percent water retention for the lot,13.2.3 The standard
47、deviation, or the coefficient ofvariation, or both, if calculated, and13.2.4 The range for the immersion times for the specimens.14. Precision and Bias14.1 PrecisionBecause of the limited use of Test MethodD2402 for water retention of textile fibers, data has beenobtained for a within laboratory com
48、parison instead of theusual interlaboratory comparison test. Two operators in onelaboratory tested twelve specimens from each of two materials,cotton and polyester, representing two levels of water reten-tion. Data, tabulated below shows more variance at the lowerlevels of water retention. See Table
49、 1.14.2 BiasThe procedure in Test Method D2402 for mea-suring the water retention of fibers has no bias because thevalue for this property can be measured only in terms of a testmethod.15. Keywords15.1 textile fibers; water retentionASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own respons
