1、Designation: D4446/D4446M 13Standard Test Method forAnti-Swelling Effectiveness of Water-Repellent Formulationsand Differential Swelling of Untreated Wood When Exposedto Liquid Water Environments1This standard is issued under the fixed designation D4446/D4446M; the number immediately following the d
2、esignation indicates theyear of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method is designe
3、d to evaluate the effective-ness of water-repellent compositions for retarding dimensionalchanges in coated wood submerged in water. It can also be usedto measure the differential swelling of untreated wood whenexposed to liquid water environments. The compositions testedare designed to be mixed unt
4、il uniform and applied by brush,roller, dip or spray to an exterior wood surface.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of t
5、he other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 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 pra
6、ctices and determine the applica-bility of regulatory limitations prior to use.2. Summary of Method2.1 Wood samples in the form of elongated slats thatrepresent the timber species or product/treatment combinationto be evaluated are exposed in soak containers. The elongatedslats are immersed in the w
7、ater-repellent formulation, condi-tioned with appropriate weighing, then subjected to immersionin distilled water for a prescribed period. The untreated slatsomit the immersion in the water-repellent formulation. Theswelling resulting from immersion for the selected time periodis determined by readi
8、ng a dial gage calibrated in increments of0.025 mm 0.001 in.2.2 A water repellent efficiency of 60 % is required to passthis test.3. Significance and Use3.1 This test method is useful in determining the relativeanti-swelling efficiency of various water-repellent formulationswhen applied to wood. It
9、is the initial means of estimating theability of water-repellent treated wood to perform satisfactorilywhen exposed to liquid water environments.3.2 The swelling differences of untreated wood specieswhen subjected to water immersion can also be determined bythis test method.3.3 This method is a basi
10、c screening test and thus providesan initial determination of the anti-swelling efficiency of waterrepellents. It is a qualitative method designed to provide areproducible means of establishing: (1) the anti-swelling effi-ciency of water-repellent formulations, and (2) the relativeswelling of untrea
11、ted wood species when both are exposed toliquid water environments.4. Apparatus4.1 Conditioning Room or Chamber, having a controlledtemperature of 23 6 2C 73.5 6 3.5F, and a controlledrelative humidity of 50 6 5 %. This room is used to establisha uniform moisture content in the test specimens.In all
12、 studiesthe temperature and relative humidity selected by the investi-gator must be stated and must remain constant throughout agiven conditioning and test period.4.2 Balance, sensitive to at least 0.01 g.4.3 Treating Tank (Fig. 1).4.4 Swellometer, as illustrated in Fig. 2, Fig. 3, and Fig. 4.Appara
13、tus can be built to be used for both 5 in. and 10 in.wafers.5. Test Specimens5.1 Wood used for these tests must be straight-grained,flat-sawn, clear, kiln-dried Ponderosa pine sapwood or othersuitable species. Cut the parent boards in a manner to givespecimens 6 mm 14 in. in the longitudinal dimensi
14、on, 38 mm112 in. in the radial dimension, and 254 mm 10 in. or 127mm 5 in. in the tangential dimension. Cut with a sharp,1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.42
15、on Architectural Coatings.Current edition approved Nov. 1, 2013. Published December 2013. Originallyapproved in 1995. Last previous edition approved in 2012 as D4446 08 (2012).DOI: 10.1520/D4446_D4446M-13.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2
16、959. United States1fine-toothed saw to obtain as smooth a surface as possiblewithout sanding. Number each specimen for identification andreference.5.1.1 Selection of Ponderosa pine sapwood can be assuredby the following quick chemical test: (1) prepare a solution of5 g of benzidine in 25 g of hydroc
17、hloric acid and 970 g ofwater, and (2) prepare a second solution consisting of a 10 %concentration of sodium nitrite in water. When the test is to bemade, pour equal amounts of the two solutions together andthen apply to the wood surface by means of brushing ordipping. The sapwood immediately shows
18、a yellowish color,while the heartwood turns dark red-brown. The colors remaindistinct after drying.5.2 Determine the swelling of an untreated specimen fromeach parent board before testing begins. Do this by equilibrat-ing the specimen in accordance with 7.1 and then testing inaccordance with 7.5.1.
19、The swelling shall not be less than 8.25mm 0.325 in. See Table 1.6. Formulations6.1 Treat the test specimens with the ready-to-use formula-tion as advocated by the manufacturer of the formulation.FIG. 1 Treating TankFive Samples Tested SimultaneouslyFIG. 2 Single Test Swellometer Tank and One Sample
20、FIG. 3 Single Test Swellometer TankWith One Sample In PlaceD4446/D4446M 1326.2 Test, experimental or control formulations may be addedto the test as desired.6.3 Establish adequate records, reference samples and iden-tification to permit independent review and analysis.7. Test Procedure7.1 Cut two ad
21、jacent specimens, both either tangentially orlongitudinally, from each board. Specimen pairs from tendifferent boards (20 test specimens in all) make a set (inaccordance with 7.3 and 7.4) for testing the water-repellency ofone formulation at one retention level. Each additional reten-tion level requ
22、ires ten additional samples. Store the testspecimens with space between each one on a raised screen orrack in the conditioning room or chamber until they reachconstant weight as determined by a uniform weight over a 48-hperiod.7.2 In comparing different water-repellent formulations, it isnecessary t
23、o determine the quantity of formulation picked upand retained by the test specimen. If the specimens are weighedbefore treatment and again immediately after being dipped inthe water-repellent formulation the difference is the weight ofthe formulation absorbed. To remove the unabsorbed treatmentfrom
24、the specimens it is recommended for water-thin viscositytype solutions to be stood on edge and rotated to ensure auniform film. For a thicker viscosity treatment it is recom-mended to use a treatment saturated brush or lint free cloth toremove excess treatment to ensure a uniform film. Then, ifrewei
25、ghed just before being placed in the swellometer, thedifference between excess treatment weight and the finalweight is the weight of the material actually retained by thespecimen.7.3 First Test:7.3.1 Maintain the formulation to be tested at a minimumtemperature of 21C 70F and thoroughly mix immediat
26、elybefore immersing the test specimens.7.3.2 Fully immerse in the Treating Tank (Fig. 1) five of theten test specimens (one from each board) in the formulation tobe tested. The immersion time for solvent-based formulationsshall be 30 s. Because of the small size of the specimens (6 mm14 in. thick) a
27、 30-s immersion period is adequate forformulation pickup. This 30-s immersion period will reflectappropriate screening test results, but is not intended to reflectthe proper treatment time for use on commercial products. Theimmersion time for water-based formulations shall be 3 min.Treat the test sp
28、ecimens while in the conditioning room/chamber or within 30 s after removal from the conditioningroom/chamber. Five untreated specimens, one from each of theboards, serve as controls.7.3.3 Place both the five treated and the five untreatedspecimens separately on a raised screen or other suitable rac
29、kthat will allow free access of air to them, and place thespecimens in the conditioning room or chamber. After 24 h,remove all specimens from the conditioning room or chamberand allow them to volatilize under normal laboratory condi-tions for 3 days. Then place all ten specimens back into theconditi
30、oning room or chamber until they reach constantweight.7.4 Second Test:FIG. 4 SwellometerTABLE 1 Natural Tangential Swelling of Selected SpeciesASpeciesTangentialSwelling,%Pine, ponderosa 6.2southern yellow 7.5Oak, red 9.5white 10.5Maple 8.3Beech 11.9Douglas-fir 7.6ASource: “Wood Handbook,” Agricultu
31、re Handbook No. 72, USDA, ForestService, Washington, DC, 1974.D4446/D4446M 1337.4.1 Pour the formulation remaining after treating (7.3.2)into a sealable glass container and allow to stand for 2 monthsat a temperature of 21 to 38C 70 to 100F. After this2-month period, decant and again test the formul
32、ation withoutshaking in accordance with 7.3. The formulation must passboth tests.7.5 Testing the Water-Repellency:7.5.1 Compare the swelling of the untreated controls withthe swelling of the matched treated specimens after each hasbeen submerged in distilled water. Measure the swelling bymeans of th
33、e Swellometer (illustrated in Fig. 2, Fig. 3, and Fig.4). Insert a specimen in the guides of the swellometer, placedso that one end bears firmly on the adjusted base and the otherend contacts the plunger of the dial. Adjustments can be madeto the sliding bar to allow for use of either the 5 in. or 1
34、0 in.wafer. Take a reading of the dial before immersing the samplein the water. Arrange the instrumented sample in the containerof distilled water maintained at 24 6 3C 75 6 5F so thatthe specimen is completely submerged (but the dial and dialstem are dry) for 30 min. At the end of the 30-min period
35、, takea second dial reading and note the difference. Test the group offive untreated controls and the group of five treated specimensseparately using fresh distilled water for each group.8. Evaluation of Results8.1 Results from the first (ten samples, that is, five pairs oftreated specimens and cont
36、rols) and second tests (ten samples)shall be separately recorded and computed. The differencebetween the swelling of each treated specimen and the swellingof its matching untreated control specimen is divided by theswelling of the untreated control specimen and multiplied by100. The average of the f
37、ive percentages calculated for eachtest represents the percent effectiveness of the water-repellentformulation per test. The average of the results from both testsrepresents the final percent of water-repellent effectiveness ofthe formulation.8.2 Historically a minimum water-repellent efficiency of6
38、0 % is required to pass this test method.9. Precision and Bias29.1 The precision of this test method is based on aninterlaboratory study of D4446, Test Method for Anti-SwellingEffectiveness of Water-Repellent Formulations and DifferentialSwelling of Untreated Wood When Exposed to Liquid WaterEnviron
39、ments, conducted from 20062007. Each of six labo-ratories tested the effectiveness of four different water repellentformulations on 10 in. and 5 in. wafers. Every “test result”represents an individual determination. All laboratories ob-tained two replicate test results for every material.2(See Table
40、2 and Table 3.)9.1.1 Repeatability (r)Two test results obtained withinone laboratory shall be judged not equivalent if they differ bymore than the “r” value for that material; “r” is the intervalrepresenting the critical difference between two test results forthe same material, obtained by the same
41、operator using thesame equipment on the same day in the same laboratory.9.1.2 Reproducibility (R)Two test results shall be judgednot equivalent if they differ by more than the “R” value for thatmaterial; “R” is the interval representing the difference be-tween two test results for the same material,
42、 obtained bydifferent operators using different equipment in different labo-ratories.9.1.3 Any judgment in accordance with these two state-ments would have an approximate 95 % probability of beingcorrect.9.2 BiasAt the time of the study, there was no acceptedreference material suitable for determini
43、ng the bias for this testmethod, therefore no statement on bias is being made.9.3 The precision statement was determined through statis-tical examination of 94 results, from six laboratories, on fourmaterials. These four fluids were described as the following:2Supporting data have been filed at ASTM
44、 International Headquarters and maybe obtained by requesting Research Report RR:D01-1175. ContactASTM CustomerService at serviceastm.org.TABLE 2 10 in. Wafer Swelling (%)FluidAverageXRepeatabilityStandardDeviationsrReproducibilityStandardDeviationsRRepeatabilityLimitrReproducibilityLimitRA 76.20 1.8
45、0 2.96 5.03 8.30B 63.17 1.92 3.50 5.36 9.80C 73.84 3.25 4.10 9.09 11.49D 9.45 1.25 3.71 3.50 10.38TABLE 3 5 in. Wafer Swelling (%)FluidAverageXRepeatabilityStandardDeviationsrReproducibilityStandardDeviationsRRepeatabilityLimitrReproducibilityLimitRA 83.26 2.42 3.69 6.78 10.32B 66.18 11.52 13.25 32.
46、25 37.11C 72.35 10.32 11.27 28.88 31.54D 7.79 3.24 3.96 9.08 11.08D4446/D4446M 134Material A: 8.4 % solids oil based clear water repellentMaterial B: clear 5 % paraffin wax petroleum distillatesolutionMaterial C: 10 % solids water based clear water repellentMaterial D: 39 % solids paraffin wax emuls
47、ion9.3.1 To judge the equivalency of two test results, it isrecommended to choose the water repellent material closest incharacteristics to the test material.10. Keywords10.1 anti-swelling; liquid water; water repellentASTM International takes no position respecting the validity of any patent rights
48、 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 responsibility.This standard is subject to revision at any ti
49、me by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the
