1、Designation: D5644 01 (Reapproved 2013)Standard Test Methods forRubber Compounding MaterialsDetermination of ParticleSize Distribution of Recycled Vulcanizate ParticulateRubber1This standard is issued under the fixed designation D5644; the number immediately following the designation indicates the y
2、ear oforiginal adoption or, in the case of revision, 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. Scope1.1 These test methods describe the procedures for deter-
3、mining average particle size distribution of recycled vulcani-zate particulate.1.2 Method A describes the Ro-tap sieve test method for 60mesh or coarser particles.1.3 Method B describes the ultrasonic technique combinedwith optical microscope especially suitable for 80 mesh or finerparticles. This p
4、rocedure is based on Test Method D3849.1.4 The values stated in SI units are to be regarded as thestandard.1.5 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 a
5、nd health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D297 Test Methods for Rubber ProductsChemical Analy-sisD1416 Test Methods for Rubber from Synthetic SourcesChemical Analysis (Withdrawn 1996)3D1566 Terminology Relat
6、ing to RubberD3182 Practice for RubberMaterials, Equipment, and Pro-cedures for Mixing Standard Compounds and PreparingStandard Vulcanized SheetsD3191 Test Methods for Carbon Black in SBR (Styrene-Butadiene Rubber)Recipe and Evaluation ProceduresD3192 Test Methods for Carbon Black Evaluation in NR(N
7、atural Rubber)D3849 Test Method for Carbon BlackMorphologicalCharacterization of Carbon Black Using Electron Micros-copyD5603 Classification for Rubber Compounding MaterialsRecycled Vulcanizate Particulate RubberE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE105 Practice for Probab
8、ility Sampling of Materials3. Terminology3.1 Definitions:3.1.1 parent compound, noriginal compound used in theproduct.3.1.2 recycled vulcanizate rubber, nvulcanized rubber thathas been processed to give particulates or other forms ofdifferent shapes, sizes, and size distributions.3.1.3 DiscussionThe
9、 words “vulcanizate” and “vulca-nized rubber” are interchangeable. Additional terminologyassociated with this classification can be found in TerminologyD1566.4. Significance and Use4.1 The particulate size distribution of vulcanizate particu-late rubber is used for the purpose of assigning a product
10、 meshor average particle size designation.4.2 The product designation for mesh size for the Ro-tapmethod (MethodA, as follows) is based on the size designationscreen which allows a range for the upper limit retained ofmaximum 5 % for up to 850 m (20 mesh) particles, maximum10 % for 600 to 150 m (30
11、to 100 mesh), and maximum 15 %for 128 to 75 m (120 to 200 mesh). No rubber particles shallbe retained on the zero screen (see Table 1, ClassificationD5603).4.3 For Method A, the weight percent retained on a specificscreen is noted whereas in Method B (ultrasonic technique),the number of particles at
12、 a particular size is counted.1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.20 on CompoundingMaterials and Procedures.Current edition approved Nov. 1, 2013. Published January 2014. Originallyapproved in 1994. Last
13、previous edition approved in 2008 as D5644 01 (2008)1.DOI: 10.1520/D5644-01R13.2For 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 o
14、nthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.4 Method B addresses problems that may be caused bytackiness and static electrical
15、 forces that recycled rubberparticles exert on each other to form agglomerates, especiallyfor 80 mesh or finer particles. This method eliminates agglom-erate formation by ultrasonically dispersing the particles.4.5 Both methods can be used as a quality control tool.5. Method A: The Ro-tap Method5.1
16、Summary of Test Method:5.1.1 Method ARo-tap Method:5.1.1.1 A 100 6 1 g specimen of the recycled rubber iscombined with a fixed amount of talc and placed on top of aseries of mesh sieves, with the coarsest sieve being on top andthe finest on the bottom. The specimen is placed in a Ro-tapshaker for 10
17、 to 20 min, depending on the grade of the recycledrubber. The weight of the rubber retained on the individualsieves is then recorded and the mesh designation of the productdetermined.6. Apparatus6.1 Mechanical Sieve Shaker4This is a mechanically op-erated sieve shaker that imparts a uniform rotary a
18、nd tappingmotion to a stack of 200-mm (8-in.) sieves in accordance with6.2. The sieve shaker should be adjusted to accommodate astack of sieves, receiver pan, and cover plate. The bottom stopsshould be adjusted to give a clearance of 1.5 mm (0.06 in.)between the bottom plate and the screens so that
19、the screenswill be free to rotate. The sieve shaker machine shall bepowered with an electric motor operating 28.75 to 29.17 Hz(1725 to 1750 rpm). This will produce 2.33 to 2.60 Hz and 280to 320 rotary motions/min. The cover plate shall be fitted witha cork stopper that shall extend from 3.00 to 9.00
20、 mm (0.118to 0.354 in.) above the metal recess. At no time shall a rubber,wood, or other material other than cork be permitted.6.2 Standard Sieves, stainless steel or brass, 200 mm (7.9in.) in diameter in accordance with Specification E11. Thesieve set should include a lid and a bottom pan.6.3 Balan
21、ce, with a sensitivity of 0.1 g.6.4 Brush.6.4.1 A Tyler Model 1778-SB soft brass wire brush forcleaning sieves 100 mesh and coarser.6.4.2 Anylon bristle brush for cleaning sieves finer than 100mesh.6.5 Jar, capacity of 500 cm3(1 pint) with large opening.6.6 Rubber Balls,5with a diameter from 25 to 5
22、0 mm (1 to2 in.) or Plastic Rings, with a height of 20 6 3 mm, an outsidediameter of 60 6 3 mm, and an inside diameter of 58 6 3 mm.The height of the balls or rings must be lesss than the depth ofthe screens being used. Enough balls or rings are needed tohave two balls or rings per sieve. Balls and
23、rings are not to beused simultaneously.6.7 Talcum Powders, usually some mixture of magnesiumsilicate, silica, magnesium oxide, magnesium-aluminum sili-cate with at least 90 % of the particles being less than 40 m(approximately 400 mesh) in size.7. Procedure7.1 Select test screens appropriate to the
24、particle sizedistribution of the product being tested. A set of two to sixsieves and a receiver pan are normally used. The actual numberof sieves is to be agreed upon by vendor and customer.7.2 Clean each screen with brush (see 6.4), making sure allparticles are removed from both sides of screen.7.3
25、 Stack test screens in order of increasing mesh size withsmallest number on top (coarsest) and highest number onbottom (finest). For products of 425 m (40 mesh) or finer, addtwo rubber balls or plastic rings per sieve. For products coarserthan 425 m (40 mesh), the use of rubber balls or plastic ring
26、sas agitation aid is optional. Rubber balls and plastic rings arenot to be used simultaneously. Same size balls shall be used onany one screen.7.4 Add bottom receiver pan to stack.7.5 Obtain approximately 150 to 200 g of vulcanizateparticulate rubber from the lot (refer to Practice E105).7.6 Prepare
27、 a 100-g specimen as follows:7.6.1 Weigh 100 g of specimen to the nearest gram.7.6.2 Weigh talc according to product gradation designa-tion. For products designated coarser than 300 m (50 mesh),weigh 5.0 g of talc. For products designated 300 m (50 mesh)or finer, weigh 15.0 g of talc.7.6.3 Add talc
28、to specimen.7.6.4 Mix thoroughly by placing talc and specimen in a500-cm3(1-pt) jar and shake the jar for a minimum of 1 min,until agglomerates are broken and talc is uniformly mixed.7.7 Place the specimen on the top sieve and place a cover onthe stack.7.8 Place the stack in the shaker.7.9 Activate
29、the shaker for 10 min for products designatedcoarser then 300 m (50 mesh). For products designated 300m (50 mesh) or finer, activate the shaker for 20 min.7.10 After the shaker completes the appropriate cycle,remove the stack.7.11 Starting with the top sieve, remove the screenedfraction by gently ta
30、pping its contents to one side and pouringthe contents on the balance and recording its mass to thenearest 0.1 g. Record any mass less than 0.1 g as trace.7.12 Brush any material adhering to the bottom of thescreen onto the next finer screen.7.13 Zero the balance in preparation for weighing theretai
31、ned contents of the next screen.7.14 Repeat 7.11 to 7.12 until all sieves in the stack and thebottom pan have been emptied, weighed, and recorded. Thisgives percent retained on each screen.4The Ro-Tap Sieve Shaker meets the specified conditions and has been foundsatisfactory for this purpose, and is
32、 available from many scientific laboratorysuppliers.5Available from various sieve manufacturing suppliers.D5644 01 (2013)28. Calculation8.1 The sum of the masses of each fraction from the sievesand the bottom pan shall not be less than the original mass ofthe specimen plus mass of talc less 2 g, or
33、greater than theoriginal mass of the specimen plus 100 % of talc added. Repeattest if either of these conditions occurs.8.2 To adjust for the addition of talc to the specimen, themass of the contents of the bottom pan is adjusted by thefollowing equation:x 5 y 2 z 2 100! (1)where:x = mass of rubber
34、in bottom pan,y = total mass of contents in bottom pan, andz = total mass of contents of all six sieves plus bottom pan.8.3 The top screen (zero screen) selected shall be one inwhich no rubber particles are retained. This “zero percentretained screen” is designated in Classification D5603 Table 1(se
35、e Note 1).8.4 The second screen in the sieve deck is for productdesignation and can contain a maximum 5 % rubber particlesfor up to 850 m (20 mesh) and a maximum 10 % for finer than850 m (20 mesh) (see Note 1).NOTE 1An example of 8.3 and 8.4 is if an 850-m (20 mesh) sievecontains zero rubber particl
36、es and a 600-m (30-mesh) sieve contains 3 %rubber particles, then the proper product designation for this material is600-m (30-mesh) particulate rubber product.9. Report9.1 Report the following information:9.1.1 Date of test,9.1.2 Proper identification of specimens,9.1.3 Identification of each sieve
37、 used,9.1.4 The residue mass on each sieve,9.1.5 The mass on the bottom pan and its adjusted mass, and9.1.6 The product mesh size determined for the specimen.10. Precision and Bias10.1 Round-robin testing will be conducted and precisionand bias statements will be balloted for inclusion when testingi
38、s completed.11. Method BUltrasonic and Light MicroscopyTechnique11.1 Summary of Test Method:11.1.1 Method BUltrasonic Technique:11.1.1.1 A 25 6 1 mg specimen of recycled rubber isultrasonically dispersed in acetone, diluted appropriately, andplaced on a microscope slide for subsequent light opticalm
39、icroscopic analysis. Photomicrographs are taken of the speci-men and then computer software is used to automaticallydetermine area measurements of the particles. The area mea-surements are mathematically converted to diameter data,which then can be used to produce statistical data andhistograms of t
40、he particle size distribution.12. Apparatus12.1 Test tubes, 75 by 10 mm glass, with corks.12.2 A benchtop tank-type ultrasonic dispersion bath withan output of 40 to 80 KHz and 105 to 270 W power.12.3 Glass microscope slides,25by75mm.12.4 Transfer pipettes, disposable polyethylene type.12.5 Light Op
41、tical Microscope, requirements for a micro-scope for this test are that it should have a transmitted lightaccessory, and also a port to attach a camera. The microscopeshould be capable of magnifications of 30.12.6 Image Analysis System, which could consist of acamera, a video TV camera, or a digital
42、 camera system.12.6.1 If a film camera is used, a photograph scanner will beneeded to be able to scan the images and transfer them to acomputer for subsequent image analysis.12.6.2 If a video rate TV camera system is used, it must beconnected to a computer frame-grabber card that will enablethe user
43、 to directly transfer images to the computer forsubsequent image analysis.12.6.3 If a digital camera is used, the images can be directlycaptured and transferred to a computer.12.7 Computer, with adequate speed and memory to be ableto do image analysis.This may vary depending on what camerasystem is
44、used for the analysis.12.7.1 Computer software capable of dimensional imageanalysis.12.7.2 Computer program to determine statistics and histo-gram information.12.7.3 Stage micrometer.13. Reagents and Materials13.1 Acetone, commercial grade.13.2 Recycled rubber crumb.14. Sampling14.1 Put 100 6 1 g of
45、 the recycled rubber in a cappedcontainer and shake it ten times to ensure that the specimen iswell-mixed and the fine particles present have not settled,before testing.15. Test Procedures15.1 Place 25 6 1 mg of recycled rubber ina3mlglass testtube.15.2 Add 1 ml of acetone to the test tube and place
46、 a corkstopper in the test tube. At the same time, prepare another testtube with 1 ml of acetone only and put in a cork stopper.15.3 Sonicate the specimen at 105 to 270 W for 5 min 6 15s in an ultrasonic bath filled to 55 6 2 mm with the surfactantsolution recommended by the manufacturer of the ultr
47、asonicbath or use a suitable substitute solution. The test tube shouldnot be touching the bottom of the ultrasonic bath, but should besuspended in the bath by suspending a beaker. Many manufac-turers have available, as an option, a basket in which a beakercan be suspended above the bottom of the bat
48、h.D5644 01 (2013)315.4 Dilute the specimen by transferring 1 to 6 drops of thesonicated solution to the other test tube containing 1 cm3ofacetone and sonicate for an additional 5 min.15.4.1 The number of drops used for the dilution depends onthe mesh grade of the specimen being analyzed and will var
49、yfrom 1 drop for 170 mesh grades and finer up to 6 drops for thelarger particle size grades. The optimum number of drops forbest dispersion for each individual mesh grade must bedetermined by experimentation.15.4.2 After the final 5 min sonification, immediately place3 sequential drops on a clean glass microscope slide and allowthe solvent to evaporate. For some grades, it may be desirableto swirl the solvent on the microscope slide gently while thesolvent is evaporating to get an even distribution of theparticles on the slide.16. Specimen Analysis
