1、Designation: D4797 17Standard Test Methods forGravimetric Analysis of White and Yellow ThermoplasticPavement Marking1This standard is issued under the fixed designation D4797; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r 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 cover procedures for the gravimetricanalysis of the binder and hydrochloric Acid (HCL) insolub
3、leparticles in white and yellow thermoplastic pavement mark-ings. The HCL insoluble particles can be retroreflective optics,such as glass beads or some other type of retroreflective optic,or non-retroreflective particles such as silica sand, or a com-bination of any two or more of these materials.1.
4、2 This standard does not address the physical separationand the individual quantification of each component when amixture of two or more HCL insoluble materials is present.Rather it requires the user to visually evaluate the HCLinsoluble material (obtained from following this test method)and report
5、the types of materials present.1.3 This standard does not purport to address the titaniumdioxide or lead chromate pigment measurement (after ashing)which is detailed in Test Methods D1394 and D126.1.4 This standard will attempt to address the interference oforganic pigments with the binder results.1
6、.5 The analytical procedures appear in the following order:SectionsPercent Binder 10Percent Retroreflective Optics orNon-Retroreflective Particles111.6 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.7 This standard does not
7、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, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international sta
8、ndard was developed in 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.
9、Referenced Documents2.1 ASTM Standards:2D126 Test Methods for Analysis of Yellow, Orange, andGreen Pigments Containing Lead Chromate and Chro-mium Oxide GreenD1394 Test Methods for Chemical Analysis of White Tita-nium PigmentsD7307 Practice for Sampling of Thermoplastic Traffic Mark-ing MaterialsD73
10、08 Practice for Sample Preparation of ThermoplasticPavement Marking MaterialsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions of Terms Specific to Thi
11、s Standard:3.1.1 ash, nthe inorganic components of thermoplasticpavement marking including the pigment, retroreflectiveoptics, and filler.3.1.2 binder, nthe organic components (resinous compo-nents) of thermoplastic pavement marking that bind thepigments, retroreflective optics, and filler together
12、as a unit.3.1.3 filler, nthe inorganic components of thermoplasticpavement marking not including the pigments, retroreflectiveoptics, or non-retroreflective particles that are consideredfunctional.3.1.4 retroreflective optic, nfunctional particle that reflectsand returns a relatively high proportion
13、 of light in a directionclose to the light source. This characteristic is maintained overa wide variation of the angle made by the incident light ray andnormal to the retroreflective surface. This includes a single1These test methods are under the jurisdiction of ASTM Committee D01 onPaint and Relat
14、ed Coatings, Materials, and Applications and are the directresponsibility of Subcommittee D01.44 on Traffic Coatings.Current edition approved Dec. 1, 2017. Published February 2018. Originallyapproved in 1988. Last previous edition approved in 2012 as D4797 12a. DOI:10.1520/D4797-17.2For referenced A
15、STM 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoh
16、ocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organ
17、ization Technical Barriers to Trade (TBT) Committee.1component structure such as a spherical glass bead or acomposite optic such as a core with a surface covered by smallreflectors or such as a cluster of small reflectors bondedtogether.3.1.5 non-retroreflective particles, nfunctional particlethat i
18、s insoluble in HCL, such as aluminum oxide, groundglass, quartz, etc., that are added for skid resistance or othernon-retroreflective functional purpose.3.1.6 pigment, ntitanium dioxide, lead chromatecolorants, other inorganic or organic pigments, or combina-tions thereof.3.1.7 thermoplastic, nSee t
19、hermoplastic pavement mark-ing.3.1.8 thermoplastic pavement marking, na highly filled100 % total solids highway marking system that when heatedto a molten state can be extruded or sprayed onto a road surfaceand when cooled forms a solid durable delineator.3.1.9 hydrochloric acid (HCL) insoluble part
20、icles,nretroreflective optics, such as glass beads or some othertype of retroreflective optic, or non-retroreflective particlessuch as silica sand, or a combination of any two or more ofthese materials.4. Summary of Test Method4.1 Thermoplastic pavement marking material is preparedfor the described
21、test methods by melting a sample to itsapplication temperature under continuous agitation. The speci-men is then poured into round patties on a non-stick surfacesuch as a baking pan. The patties are then broken into piecesfor ignition in a muffle furnace. The percent binder is calcu-lated from the a
22、shed specimen. The various tests for retrore-flective optics, non-retroreflective particles, titanium dioxide,and lead chromate pigment can be performed later on the ashedresidue. Determining the binder content of organic pigmentcontaining thermoplastic may not be as straight forward.Specimen select
23、ion and preparation are the same for eithersample type.5. Significance and Use5.1 The function of these test methods is to define thepercent of binder and retroreflective optics or non-retroreflective particles in the composition of the thermoplasticpavement marking as defined by the applicable spec
24、ificationfor the manufacture of a specific thermoplastic pavementmarking. The subsequent sample, as a result of ashing can beused to later test for the presence of titanium dioxide, leadchromate and possibly organic pigments.6. Apparatus6.1 Balance, analytical, capable of weighing to 0.1 mg.6.2 Cruc
25、ibles, 30+ mL, porcelain or aluminum pan.(WarningSome aluminum pans will degrade at high tem-peratures.)6.3 Desiccator.6.4 Furnace (Muffle), capable of maintaining 540C(1004F).6.5 Hot Plate or Heating Mantle, capable of heating a can ofthermoplastic to 218C (425F).6.6 Sieve, 3 in., 45-m (No. 325) (m
26、etal).6.7 Buchner Funnel.6.8 Vacuum Flask and Rubber Hose.6.9 Vacuum Pump.6.10 Oven capable of reaching 218C (425F).6.11 Microwave Oven.6.12 400 mL Beaker or acid proof container.6.13 Magnetic Stirring Bar.6.14 Magnetic Stirring Plate.6.15 Spatula.6.16 Glass Beaker or Plastic Cup.7. Reagents7.1 Hydr
27、ochloric Acid Solution (HCL) (1 + 1 concentratedHCL diluted with equal volume of water).7.2 Hydrochloric Acid, Concentrated (HCL).8. Sampling8.1 Samples may be obtained in accordance with PracticeD7307 by an appropriate quartering or riffle sampling methodwhere deemed necessary considering the physi
28、cal form of thematerial.9. Preparation of Specimens9.1 Melt a sample of thermoplastic pavement marking inaccordance with Practice D7308 to 218C (425F) (or permanufacturers recommended processing temperature) undercontinuous agitation on a hot plate or stir every 15 min in anoven set at 218C (425F) o
29、r per manufacturers recommendedprocessing temperature.NOTE 1Thermoplastic pavement marking is manufactured in a widevariety of viscosities at 218C. Some viscosities are so low that theretroreflective optics settle quickly. In order to prevent any settlementduring the sampling process, removing the t
30、est sample at a lowertemperature is warranted. Some thermoplastic test samples are best pouredas low as 160C (320F) as long as they can flow into patties.9.2 Flow the sample out on a smooth clean non-stick surfaceand allow it to cool to room temperature. Patties approximately3mm(18 in.) thick are us
31、ually easy to break into specimens forthe described analysis.9.3 Break the specimen into small pieces and weigh to thenearest 0.1 mg into a weighed crucible that is at least twice thevolume of specimen. The binder test can be done on samples assmall as 10 g (0.353 g) and be effective. Larger samples
32、 cansupply more retroreflective optics or non-retroreflective par-ticles for their evaluation later if required.9.4 Cover the crucible and place into a muffle furnacepreheated to 540C (1004F) and ash for 1 hour or until nocarbonaceous material remains.9.5 Remove the crucible/pan with the ashed remai
33、ns of thespecimen and place into a desiccator and cool to roomtemperature.D4797 17210. Percent Binder10.1 InterferencesIf yellow organic-pigment-containingthermoplastic pavement marking samples are ashed, the or-ganic pigment may begin to degrade; therefore increasing thebinder results. If the theor
34、etical amount of organic pigmentcontent of the sample is known and an assumption can be madeas to whether some or all the organic pigment has degraded(depending on its degradation temperature and the amount offiller in the pigment), then that amount can be accounted for inthe calculation in Eq 1.10.
35、2 ProcedureWeigh the crucible and ash (see Section 9)to the nearest 0.1 mg and calculate the percent binder D asfollows:D 5 1 2 S W! 3 100 (1)where:S = ashed weight of thermoplastic specimen, g, (crucible +ash wt.) crucible wt.W = weight of thermoplastic specimen, g, (crucible + ther-moplastic speci
36、men) crucible wt.11. Percent Retroreflective Optics (RO) or Non-retroreflective Particles (NRP) using HydrochloricAcid (HCL)11.1 Procedure:11.1.1 Weigh the crucible and ash (see Section 9) to 0.1 mgand calculate the percent ash.11.1.2 After the ashed material has been weighed, transferthe ash to a 4
37、00-mL beaker or other acid-proof container andwith minimal pressure, break apart the ashed specimen withoutcrushing the retroreflective optics.11.1.3 Add to the ash approximately 50 to 150 mL (1.7 to 5oz.) of cold 1 + 1 HCL and stir occasionally until most of theeffervescence has ceased. (WarningThi
38、s is best performedunder a vented hood. Also, this procedure can be performedusing warmed HCL but is not necessary.)11.1.4 Once the solution has stopped effervescing, dilute thecontents with as much water as possible to allow the RO orNRP to settle. Decant the water and particulate carefully so asno
39、t to lose RO or NRP.11.1.5 If all the ash residue has not gone into solution,reintroduce HCL solution and stir. Continuous agitation canbest be achieved with a magnetic stirring bar and magneticstirrer. Stirring with a spatula can achieve similar results.11.1.6 Continue adding HCL or diluting with w
40、ater anddecanting until only beads and clear water are left in thecup/beaker.11.1.7 Transfer the residue into a weighed 3-in. 45-m (No.325) sieve or a Buchner funnel containing a weighed corru-gated coffee filter and wash with enough cold water to removeany residue. If the RO or NRP do not appear cl
41、ean, then repeatthe acid washing process.11.1.8 Dry the sides and the bottom of the sieve with a papertowel and dry for 1 hour in a gravity oven preheated to 100C(212F). If using a Buchner funnel and coffee filters, a vacuumcan be pulled on the system to evacuate the water and then theRO/NRP-contain
42、ing-filters can be dried in a oven or micro-wave oven.11.1.9 Place the sieve or coffee filter in a desiccator and coolto room temperature.11.1.10 Weigh the sieve/filter and HCL insoluble particles(RO or NRP) to 0.1 mg and calculate the percent as follows(see Note 2):NOTE 2Most thermoplastic pavement
43、 marking ashed residue which isinsoluble in HCL is a retroreflective optic.%HCL Insoluble Particles 5 R/W! 3100 (2)where:R = weight of residue after acid wash (g) (not includingsieve/filter wt.)W = original weight of thermoplastic specimen (g) (notincluding crucible wt.)11.1.11 After completing the
44、calculation examine thesample of acid insoluble particles obtained during the test todetermine the qualitative composition of the material. Includein the report the qualitative composition of the residue. Forexample, the HCL insoluble particles obtained from this testare composed of 100 % retrorefle
45、ctive optics, or the HCLinsoluble particles obtained from this test are composed of bothretroreflective optics and non-retroreflective particles.12. Precision and Bias312.1 The precision of this test method is based on aninterlaboratory study of ASTM D479712, Standard TestMethods for Gravimetric Ana
46、lysis of White and Yellow Ther-moplastic Traffic Marking, conducted in 2012. Seven labora-tories participated in the study, testing four different thermo-plastic materials. Every analyst was instructed to report fourreplicate test results in this study. Practice E691 was followedfor the study design
47、; the details are given in ASTM ResearchReport No. RR:D01-1166.12.1.1 Repeatability Limit (r)Two test results obtainedwithin one laboratory shall be judged not equivalent if theydiffer by more than the “r” value for that material; “r”istheinterval representing the critical difference between two tes
48、tresults for the same paint, obtained by the same operator usingthe same equipment on the same day in the same laboratory.12.1.1.1 Repeatability limits are listed in Table 1 and Table2.12.1.2 Reproducibility Limit (R)Two test results shall bejudged not equivalent if they differ by more than the “R”
49、valuefor that material; “R” is the interval representing the criticaldifference between two test results for the same paint, obtainedby different operators using different equipment in differentlaboratories.12.1.2.1 Reproducibility limits are listed in Table 1 andTable 2.12.1.3 The above terms (repeatability limit and reproduc-ibility limit) are used as specified in Practice E177.12.1.4 Any judgment in accordance with statements 12.1.1and 12.1.2 would have an approximate 95 % probability ofbeing correct.3Supporting data have
