1、Designation: D5071 06 (Reapproved 2013)Standard Practice forExposure of Photodegradable Plastics in a Xenon ArcApparatus1This standard is issued under the fixed designation D5071; 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. Scope*1.1 This practice covers specific procedures and test condi-tions that are applicable for xenon arc exposure of
3、photode-gradable plastics conducted in accordance with Practices G151and G155. This practice also covers the preparation of testspecimens, the test conditions best suited for photodegradableplastics, and the evaluation of test results.1.2 This standard does not purport to address all of thesafety co
4、ncerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1This practice is technically equivalent to ISO 4892-2 andPractice D2565 wh
5、ich cover xenon arc exposures of plastics intended forlong term use in outdoor applications.2. Referenced Documents2.1 ASTM Standards:2D882 Test Method for Tensile Properties of Thin PlasticSheetingD883 Terminology Relating to PlasticsD1293 Test Methods for pH of WaterD2565 Practice for Xenon-Arc Ex
6、posure of Plastics In-tended for Outdoor ApplicationsD3593 Test Method for Molecular Weight Averages/ Distri-bution of Certain Polymers by Liquid Size-ExclusionChromatography (Gel Permeation Chromatography GPC)Using Universal Calibration (Withdrawn 1993)3D3826 Practice for Determining Degradation En
7、d Point inDegradable Polyethylene and Polypropylene Using a Ten-sile TestD3890 Test Method for Number of Strokes to Prime aMechanical Pump DispenserD5870 Practice for Calculating Property Retention Index ofPlasticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a T
8、est MethodG113 Terminology Relating to Natural and Artificial Weath-ering Tests of Nonmetallic MaterialsG141 Guide for Addressing Variability in Exposure Testingof Nonmetallic MaterialsG147 Practice for Conditioning and Handling of Nonmetal-lic Materials for Natural and Artificial Weathering TestsG1
9、51 Practice for Exposing Nonmetallic Materials in Accel-erated Test Devices that Use Laboratory Light SourcesG155 Practice for Operating Xenon Arc Light Apparatus forExposure of Non-Metallic MaterialsG169 Guide for Application of Basic Statistical Methods toWeathering Tests2.2 Other Standards:ISO 48
10、92-2 PlasticsMethod of Exposure to LaboratoryLight SourcesPart 2, Xenon Arc Sources4Publication C.I.E. No. 85 (1989)5DIN 53384 Testing of Plastics: Artificial Weathering orExposure in Laboratory Exposure Weathering or Exposurein Laboratory Exposure Apparatus to UV Radiation43. Terminology3.1 Definit
11、ionsThe definitions given in TerminologiesD883 and G113 are applicable to this practice.4. Significance and Use4.1 Materials made from photodegradable plastics are in-tended to deteriorate rapidly when exposed to solar radiation,oxygen, heat, moisture and other degrading elements of theweather. This
12、 practice is used for evaluating the photodegrad-ability of plastics when exposed in an apparatus that produces1This practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.96 on Environmentally DegradablePlastics and Biobased Products.
13、Current edition approved April 1, 2013. Published April 2013. Originallyapproved in 1991. Last previous edition approved in 2006 as D5071 - 06. DOI:10.1520/D5071-06R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual
14、 Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.5P
15、ublication No. CIE 85, 1stEd., 1989 Technical Report, “Solar SpectralIrradiance,” available from U.S. National Committee CIE, Mr. Thomas M. Lemons,TLA-Lighting Consultants, Inc., 72 Loring Ave., Salem, MA 01970.*A Summary of Changes section appears at the end of this standardCopyright ASTM Internati
16、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1simulated daylight (1,2)6and controlled temperature and mois-ture. The exposure used in this practice is not intended tosimulate the deterioration caused by localized weather phe-nomena such as atmospheric poll
17、ution, biological attack, andsalt water exposure. There can be no positive correlation ofexposure results between this and other laboratory weatheringdevices.4.2 Variations in results can be expected when operatingconditions are varied within the accepted limits of this practice.Therefore, all test
18、results using this practice must be accom-panied by the specific operating conditions required in Section9. Refer to Practice G151 for detailed information on thecaveats applicable to use of results obtained in accordance withthis practice.4.3 The results of laboratory exposure cannot be directlyext
19、rapolated to estimate absolute rate of deterioration by theenvironment because the acceleration factor is material depen-dent and can be significantly different for each material and fordifferent formulations of the same material. However, exposureof a similar material of known outdoor performance,
20、a control,at the same time as the test specimens allows comparison of thedurability relative to that of the control under the test condi-tions. Evaluation in terms of relative durabilities also greatlyimproves the agreement in test results among different labora-tories (3).4.4 Test results will depe
21、nd on the care that is taken tooperate the equipment in accordance with Practice G155.Significant factors include regulation of line voltage, freedomfrom salt or other deposits from water, temperature andhumidity control and condition and age of the burners andfilters.NOTE 2Additional information on
22、 sources of variability and onstrategies for addressing variability in the design, execution and dataanalysis of laboratory accelerated exposure tests is found in Guide G141.4.5 Before proceeding with this practice, it is commonpractice to reference the specifications of the material beingtested. An
23、y test specimen preparation, conditioning,dimensions, or testing parameters, or combination thereof,covered in the material specification shall take precedence overthose mentioned in this practice. If there are no materialspecifications, then the default conditions apply.5. Apparatus5.1 The exposure
24、 apparatus employed shall use as thesource of radiation a xenon arc lamp and apparatus whichconforms to the requirements defined in Practices G151 andG155.5.1.1 Unless otherwise specified, the spectral power distri-bution (SPD) of the xenon lamp shall conform to the require-ments of Table 1 in Pract
25、ice G155 for a xenon lamp withdaylight filters.6. Test Specimens6.1 The size and shape of specimens to be exposed will bedetermined by the specifications of the particular test methodused to evaluate the effects of the exposure on the specimens;the test method shall be determined by the parties conc
26、erned.Where practical, it is recommended that specimens be sized tofit specimen holders and racks supplied with the exposureapparatus. Unless supplied with a specific backing as anintegral part of the test, specimens shall be mounted so thatonly the minimum specimen area required for support by theh
27、older is covered. This unexposed surface must not be used aspart of the test area. To provide rigidity, flexible specimens aretypically attached to, or backed by, a panel made of aluminum,0.025-in. (0.64-mm) thick.6.2 Unless otherwise specified, prepare at least three repli-cate specimens of each te
28、st and control material to be exposed.6.3 Retain a supply of unexposed file specimens of allmaterials evaluated.6.3.1 When destructive tests are used, it is recommendedthat a sufficient number of file specimens be retained so that theproperty of interest can be determined on the file specimenseach t
29、ime the exposed materials are evaluated.6.4 Follow the procedures described in Practice G147 foridentification and conditioning and handling of specimens oftest, control, and reference materials prior to, during, and afterexposure.6.5 Do not mask the face of a specimen for the purpose ofshowing on o
30、ne panel the effects of various exposure times.Accurate results are not guaranteed since the masked portion ofthe specimen is still exposed to temperature and humiditycycles that, in many cases, will affect results.6.6 In some materials, specimen thickness markedly affectsthe test results. Thickness
31、 of test and control specimens shall bewithin 610 % of the nominal dimensions.NOTE 3Thickness of a specimen is especially important whenmechanical properties are being investigated.7. Procedure7.1 It is recommended that a control material be exposedsimultaneously with experimental materials for dete
32、rminationof relative performance, if performance comparisons are notbeing made between the test materials themselves. All con-cerned parties must agree on the control material used.7.1.1 Identification of any control specimen used shallaccompany the report.7.2 Mount the test specimens in the specime
33、n exposure areawith the test surfaces facing the lamp. When the test specimensdo not completely fill the exposure area, fill the empty spaceswith blank metal panels to maintain the test conditions withinthe chamber.7.3 Confine specimens to an exposure area where theirradiance is at least 90 % of tha
34、t measured at the center of theexposure area. In areas where the irradiance is between 70 and90 % of maximum irradiance, either reposition in accordancewith the schedule agreed upon by all concerned parties, orrandomly position replicate specimens and determine theaverage change in property. Determi
35、ne irradiance uniformity inaccordance with Practice G151.6The boldface numbers in parentheses refer to a list of references at the end ofthis standard.D5071 06 (2013)27.4 Table 1 describes three cycles that have been used forxenon arc exposure of photodegradable plastics. Unless other-wise specified
36、, use Cycle 1 for exposure of materials that willbe tested for toxicity after exposure. Obtain mutual agreementamong all concerned parties for the specific exposure cycle tobe used. Other test conditions can be used by mutual consentprovided that the conditions are reported in conformance withSectio
37、n 9. Different conditions can result in significant differ-ences in test results.7.4.1 Unless otherwise specified, operate the device so thatthe allowable deviation about the set point conditions given inTable 1 is within the limits specified in Table 2. If the actualoperating conditions do not agre
38、e with the machine settingsafter the equipment has stabilized, discontinue the test andcorrect the cause of the disagreement before continuing.7.5 Unless otherwise specified, do not remove specimensfrom the exposure apparatus for more than 24 h and thenreturned for additional testing, since this typ
39、e of interruptioncan alter results. Report any elapsed time in accordance withSection 9.NOTE 4Since the stability of the file specimen can also be time-dependent, users are cautioned that over prolonged exposure periods, orwhen small differences in the order of acceptable limits are anticipated,comp
40、arison of exposed specimens with the file specimen are not guaran-teed to be valid. Instrumental measurements are recommended wheneverpossible.7.6 Water Purity:7.6.1 The purity of water used for specimen spray is veryimportant. Without proper treatment to remove cations, anions,organics and particul
41、arly silica, exposed panels will developspots or stains that are not typical in exterior exposures.7.6.2 Follow the requirements for water purity described inPractice G151.7.6.3 If specimens are found to have deposits or stains afterexposure in the apparatus, check the water purity to determineif it
42、 meets the requirements of 7.6.2. On some occasions,exposed specimens are contaminated by deposits from bacteriathat grow in the purified water used for specimen spray. Ifbacterial contamination is detected, flush the entire systemused for specimen water spray with chlorine and thoroughlyrinse prior
43、 to resuming exposures.TABLE 1 Test Cycles Commonly Used for Xenon Arc Exposure of Photodegradable PlasticsACycleNumberCycleDescriptionB,C,DUninsulatedBlack PanelTemperature (C)C,D,ETypicalIrradianceB,C,DTypical UsesF1 Continuous light 63 0.35 W/(m2 nm)at 340 nmRequired when exposedspecimens will be
44、 used fortoxicity tests41.5 W/(m2 nm)from 300 400 nm365 W/(m2 nm)from 300 800 nm2 Continuous lightusing 102 minlight only and18 min light andwater sprayG63 0.35 W/(m2 nm)at 340 nmExposures when a slightmoisture stress is desiredH41.5 W/(m2 nm)from 300 400 nm36520W/(m2 nm)from 300 800 nm3 18 h contin
45、uous lightusing 102 minlight only and18 min light andwater sprayG63 0.35 W/(m2 nm)at 340 nmRecommended when adark period with highmoisture stress is required41.5 W/(m2 nm)from 300 400 nm365 W/(m2 nm)from 300 800 nm6 h dark using:95 % relative humidity(no water spray)repeated continuously38AThe cycle
46、s described are not listed in any order indicating importance, and are not necessarily recommended for the applications shown.BAs stated in 5.1.1, the SPD of the xenon lamp shall conform to the requirements of Practice G155 for a xenon lamp with daylight filters.CUnless otherwise specified, operate
47、the apparatus to maintain the specified operational fluctuations in Table 2 for the parameters in this table. If the actual operatingconditions do not agree with the machine settings after the equipment has stabilized, discontinue the test and correct the cause of the disagreement before continuing.
48、DSet points and operational fluctuations could either be listed independently of each other, or they could be listed in the format: Set point operational fluctuations. Theset point is the target condition for the sensor used at the operational control point as programmed by the user. Operational flu
49、ctuations are deviations from the indicatedset point at the control point indicated by the readout of the calibrated control sensor during equilibrium operation and do not include measurement uncertainty. At theoperational control point, the operational fluctuation can exceed no more than the listed value at equilibrium. When a standard calls for a particular set point, the userprograms that exact number. The operational fluctuations specified with the set point do not imply that the user is allowed to program a set point higher or lower than theexact s
