1、Designation: D6111 13D6111 13aStandard Test Method forBulk Density And Specific Gravity of Plastic Lumber andShapes by Displacement1This standard is issued under the fixed designation D6111; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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. Scope*1.1 This test method covers the determination of the bulk density and specific gravity of plastic lum
3、ber and shapes in their “asmanufactured” form. As such, this is a test method for evaluating the properties of plastic lumber or shapes as a product and nota material property test method.1.2 This test method is suitable for determining the bulk specific gravity or bulk density by immersion of the e
4、ntire item or arepresentative cross section in water. This test method involves the weighing of a one piece specimen in water, using a sinker withplastics that are lighter than water. This test method is suitable for products that are wet by, but otherwise not affected by waterfor the duration of th
5、e test.1.3 Plastic lumber and plastic shapes are currently made predominately from recycled plastics. However, this test method wouldalso be applicable to similar manufactured plastic products made from virgin resins where the product is non-homogeneous in thecross-section.1.4 The values stated in S
6、I units are to be regarded as standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylim
7、itations prior to use.NOTE 1There is no known ISO equivalent to this test method.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1622 Test Method for Apparent Density of Rigid Cellular PlasticsD1898 Practice for Samp
8、ling of Plastics (Withdrawn 1998)3D5033 Guide for Development of ASTM Standards Relating to Recycling and Use of Recycled Plastics (Withdrawn 2007)3D6108 Test Method for Compressive Properties of Plastic Lumber and ShapesE1 Specification for ASTM Liquid-in-Glass ThermometersE12 Terminology Relating
9、to Density and Specific Gravity of Solids, Liquids, and Gases (Withdrawn 1996)3E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3. Terminology3.1 Definitions:3.1.1 density, bulkthe weight per unit volume of a material including voids inherent in materi
10、al as tested. (Terminology D883)3.1.1.1 DiscussionSpecific gravity at 23/23C can be converted to density 23C, g/cm3, as follows:D23C,g/cm35sp gr 23/23C30.9976 (1)1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.20 on
11、Plastic Lumber (SectionD20.20.01).Current edition approved June 1, 2013Sept. 1, 2013. Published June 2013September 2013. Originally approved in 1997. Last previous edition approved in 20092013 asD6111 - 09.D6111 - 13. DOI: 10.1520/D6111-13.10.1520/D6111-13A.2 For referencedASTM standards, visit theA
12、STM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is
13、not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropri
14、ate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1
15、3.1.2 plastic lumber, na manufactured product made primarily from plastic materials (filled or unfilled), typically used as abuilding material for purposes similar to those of traditional lumber, which is usually rectangular in cross-section. (TerminologyD883)3.1.2.1 DiscussionPlastic lumber is typi
16、cally supplied in sizes similar to those of traditional lumber board, timber and dimension lumber; howeverthe tolerances for plastic lumber and for traditional lumber are not necessarily the same. (Terminology D883)3.1.3 plastic shape, na manufactured product composed of more than 50 weight percent
17、resin, and in which the productgenerally is not rectangular in cross-section, may be filled or unfilled, and may be composed of single or multiple resin blends.3.1.4 resin, na solid or pseudosolid organic material often of high molecular weight, which exhibits a tendency to flow whensubjected to str
18、ess, usually has a softening or melting range, and usually fractures conchoidally. (Terminology D883)3.1.4.1 DiscussionIn a broad sense, the term is used to designate any polymer that is a basic material for plastics.3.1.5 specific gravity, bulk (of solids)the ratio of the weight in air of a unit vo
19、lume of a permeable material (including bothpermeable and impermeable voids normal to the material) at a stated temperature to the weight in air of equal density of an equalvolume of gas-free distilled water at a stated temperature. The form of expression shall be the following:bulk specific gravity
20、 x/yC (2)where:x = temperature of the material, andy = temperature of the water.3.1.5.1 DiscussionThe accuracy of bulk density determinations is so low that corrections for air buoyancy and variations inthe value for the acceleration of gravity are not warranted. Hence, this definition is based on w
21、eights in air. (Terminology E12)3.2 Additional definition of terms applying to this test method appear in Terminology D883 and Guide D5033.4. Summary of Test Method4.1 Determine the weight of a specimen of the plastic lumber or shape in air. The specimen is then immersed in water, its weightupon imm
22、ersion is determined, and its bulk specific gravity calculated.5. Significance and Use5.1 The specific gravity or density of a solid is a property that can be measured conveniently to follow physical changes in asample, to indicate degree of uniformity among different sampling units or specimens, or
23、 to indicate the average density of a largeitem.5.2 It is possible that variations in density of a particular plastic lumber or shapes specimen will be due to changes incrystallinity, loss of plasticizer/solvent content, differences in degree of foaming, or to other causes. It is possible that porti
24、ons ofa sample will differ in density because of difference in crystallinity, thermal history, porosity, and composition (types or proportionsof resin, plasticizer, pigment, or filler).NOTE 2Reference is made to Test Method D1622.5.3 Density is useful for calculating strength to weight and cost to w
25、eight ratios.5.4 If the cross-sectional area of the specimen is required for future testing on a particular sample, it is acceptable to determineit from a specific gravity measurement, see Eq 5.6. Apparatus6.1 BalanceA balance large enough to accommodate the specimen conveniently, with a precision w
26、ithin 1.0 mg, accuracywithin 0.05 % relative (that is 0.05 % of the weight of the specimen in air), and equipped with a means of support for the immersioncage.6.1.1 Calibrate the balance at least annually in accordance with the manufacturers instructions for zero point, sensitivity, andabsolute accu
27、racy.6.2 Immersion Cage:6.2.1 WireA corrosion-resistant wire for suspending the cage.6.2.2 CageA device large enough to support the bottom of the specimen and when weighted will transfer the sinker force tothe specimen to keep it from floating. Refer to the sample immersion cage diagrammed in Fig. 1
28、.6.2.3 SinkerA sinker for use with specimens of plastics that have specific gravities less than 1.000. The sinker shall: becorrosion-resistant; have a specific gravity of not less than 7.0; have smooth surfaces and a regular shape; and be slightly heavierthan necessary to sink the specimen. It is im
29、portant that the sinker be easily attached to the cage.D6111 13a26.3 Immersion VesselA beaker, bucket, or other wide-mouthed vessel for holding the water and immersed cage.6.4 ThermometerA thermometer having not fewer than four divisions per C over a temperature range of not less than 5Cabove and be
30、low the standard temperature, and having an ice point for calibration. A thermometer short enough to be handledinside the balance case will be found convenient.ASTMThermometer 23C (see Specification E1) andAnschtz-type thermometershave been found satisfactory for this purpose.NOTE 3A thermometer sho
31、rt enough to be handled inside the balance case will be found convenient. ASTM Thermometer 23C (see SpecificationE1) and Anschtz-type thermometers have been found satisfactory for this purpose. Alternative thermometers with equivalent or better accuracy,precision, and properties while covering the t
32、emperature range of 6.4 are acceptable.7. Materials7.1 WaterThe water shall be distilled, deionized, or demineralized.8. Sampling8.1 The sampling units used for the determination of specific gravity shall be representative of the quantity of product for whichthe data are required, in accordance with
33、 Practice D1898.8.2 Plastic lumber and shapes are typically foamed, layered or hollow, varying in material properties over the cross section. Toestablish the overall specific gravity for a section, complete unmachined elements or representative cross sections of these elementsshall be used.9. Test S
34、pecimens9.1 Test specimens for determining the bulk specific gravity or bulk density of plastic lumber and shapes shall be cut from the“as manufactured” profile. Plastic lumber is generally non-uniform through the cross-section; no machining operations other thanthose required to provide flat, paral
35、lel ends shall be conducted. Care must be taken in cutting specimens to avoid changes in densityresulting from compressive stresses or frictional heating.9.2 The standard test specimen shall be in the form of a right cylinder or prism where height is twice its minimum cross-sectionor diameter.NOTE 4
36、Expect for specified tolerances, the specimen requirements given in 9.1 and 9.2 above are the same for Test Method D6108. It is acceptable,therefore, to use specimens prepared in accordance with Test Method D6108 to determine bulk specific gravity or density prior to being subjected to thedestructiv
37、e compression tests.9.3 When the cross section of the material being tested is known or suspected to be porous, hollow, or contain voids, or both,seal the cut ends to prevent ingress of water from producing false results.9.3.1 Unreinforced plastic packaging tape that is nominally 0.05 mm in thicknes
38、s has been found suitable for sealing the cutends. Because the weight of the tape is small compared to the weight of the specimens, use of the plastic tape will have a negligibleeffect on the final density and specific gravity calculations. Use of a different type of tape or any other method to seal
39、 the cut endswill require correction factors for accurate results.FIG. 1 Typical Configuration of Test ApparatusD6111 13a39.4 The specimen shall be free from oil, grease, and other foreign matter.10. Conditioning10.1 ConditioningUnless otherwise specified by the customer or product specifications, c
40、ondition the test specimens at 23 62C and 50 6 5 % relative humidity for not less than 40 hours prior to test in accordance with Procedure A of Practice D618. Incases of disagreement, the tolerances shall be 61C and 62 % relative humidity.10.2 Test ConditionsUnless otherwise specified by the custome
41、r or product specification, conduct tests in the standardlaboratory atmosphere of 23 6 2C and 50 6 5 % relative humidity. In cases of disagreement, the tolerances shall be 61C and62 % relative humidity.11. Procedure11.1 Weigh the specimen in air to the nearest 1.0 mg. Record this as a, the weight of
42、 the specimen in air.11.1.1 It is acceptable to weigh the specimen in air after hanging from the wire. When this is done, record the weight of thespecimen, a = (weight of specimen + wire + cage, in air) (weight of wire + cage, in air).11.2 Attach to the balance a piece of fine wire sufficiently long
43、 to reach from the balance to the base of the immersion vessel.Attach the immersion cage to the wire such that it is suspended a marked distance above the base of the immersion vessel. Placethe specimen in the cage, using sinkers if needed.11.3 Completely immerse the suspended specimen (and sinkers,
44、 if used) in water (see 7.1) at a temperature of 23 6 1C. Thevessel must not touch wire or specimen.11.4 Remove any bubbles adhering to the specimen, wire, cage, or sinker. Usually these bubbles can be removed by rubbingthem with another wire. If the bubbles cannot be removed by this method or if bu
45、bbles are continuously formed (as from dissolvedgases), the use of vacuum is recommended. If the water does not wet the specimen, a few drops of a wetting agent shall be added.11.5 Determine the weight of the suspended specimen to the nearest 1.0 mg. Record this weight as b (the weight of theimmerse
46、d specimen, wire, cage, and sinker). Unless otherwise specified, weigh rapidly in order to minimize absorption of waterby the specimen.11.5.1 For some materials, it will be necessary to change the sensitivity adjustment of the balance to overcome the dampingeffect of the immersed specimen.11.6 Weigh
47、 the wire, cage, and sinker, if used, in water with immersion to the same depth as used in the previous step. Recordthis weight as w (weight of the wire, cage, and sinker in liquid).11.6.1 It is acceptable to mark the level of immersion by means of a shallow notch in the wire. The finer the wire, th
48、e greaterthe tolerance permitted in adjusting the level of immersion between weighing.11.6.2 When the wire and cage are left attached to the balance during a series of determinations, determine the weight a withthe aid of a tare on the balance. When this done, take care that the change in weight of
49、the wire and cage (for example, from visiblewater) between readings does not exceed the desired precision.11.7 Repeat the procedure for a minimum of five specimens per sample.12. Calculation12.1 Calculate the bulk specific gravity of the sample as follows:Sp gr23/23C5a/a1w 2b! (3)where:a = overall weight of specimen, without wire or sinker, in air,b = overall weight of specimen (and of cage and sinker) completely immersed and of the wire partially immersed in liquid, andw = overall weight of totally immersed sinker, cage, and partially immer
