1、Designation: D7436 12Standard Classification System forUnfilled Polyethylene Plastics Molding and ExtrusionMaterials with a Fractional Melt Index Using ISO Protocoland Methodology1This standard is issued under the fixed designation D7436; the number immediately following the designation indicates th
2、e year 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.INTRODUCTIONThis material specification is intended to provide
3、 a callout system for polyethylene utilizingspecimen preparation procedures and test methods based primarily on ISO standards.1. Scope*1.1 This classification system provides for the identificationof unfilled polyethylene plastics molding and extrusion mate-rials, with a melt index of 7to # 11 melt
4、flow rate (190C/21.6Kg).NOTE 4It is recognized that some high-density polyethylene plasticsof very high molecular weight may have densities slightly less than 0.960,yet in all other respects they are characteristic of Class 4 materials.Similarly, there are other polyethylene plastics of very high mo
5、lecularweight having densities less than 0.941 that, in all other aspects, are morecharacteristic of Class 2 than of Class 3 materials.NOTE 5Use the following terms in describing polyethylene plastics:Class 1 (0.910 to 0.925) = low densityClass 2 (0.925 to 0.940) = medium densityClass 3 (0.940 to 0.
6、960) = high density-low rangeClass 4 (0.960) = high density-high rangeTABLE PE Basic Requirement of Polyethylene PlasticsGroup Description Class Description Grade MeltFlowRateAMeltFlowRateBTensileStress atYield,CMPa,minNominalStrain atBreak,C%, minTensileModulus,DMPa,min1 Branched 1 LowDensity1 #7 .
7、0.910 #0.92527#113140.1# 0.4 9.5 400504# 1 9.5 30002 MediumDensity1 #70.925#0.94027#1131D7436 122TABLE ContinuedGroup Description Class Description Grade MeltFlowRateAMeltFlowRateBTensileStress atYield,CMPa,minNominalStrain atBreak,C%, minTensileModulus,DMPa,min40.1# 0.4 11 400504# 1 11 20000 other
8、02 Linear 1 LowDensity1 #70.910 #0.92527#113140.1# 0.4 11 500504# 1 11 400 20002 MediumDensity1 #70.925 #0.94027#113140.1# 0.4 16 400 600504# 1 16 200 50003 HighDensity1 #7 20 7000.940#0.96027#1123 9003 11 23 90040.1# 0.4 24 600 1000504# 1 25 400 110004 HighDensity1 #70.960 2 7 #113140.1# 0.4 28 400
9、504# 1 28 300 120000 other 000 Other 0 other 0AISO 1133 melt flow rate = g/10 min at 190C/21.6 Kg.BISO 1133 melt flow rate = g/10 min at 190C/2.16 Kg.CISO 3167, Type 1B tensile bars, HDPE and MDPE tested at 50 mm/min. For densities # 0.925 test at 500 mm/min.DISO 527-1 and ISO 527-2 at 1 mm/min stra
10、in rate, chord modulus between 0.05 % and 0.25 % strain.TABLE A Detail RequirementsAfor Polyethylene PlasticsDesignation orOrder No.Property 0 123456 78 91 Tensile stress at yield,BMPa ISO 527-1 and ISO 527-2,minunspecified 4 8 12 16 21 30 35 specify valueC2 Nominal strain at break,B%,ISO 527-1 and
11、ISO 527-2,minunspecified 25 50 200 400 600 800 1000 specify valueC3 Tensile Modulus,DMPa, ISO 527-1 and ISO 527-2,minunspecified 50 100 200 400 600 800 1000 specify valueC4EEnvironmental stress-crack resistance,hrs, min F50,FTest Method D1693unspecified 24 48 96 168 336 672 1008 specify valueC5 To b
12、e determined unspecified specify valueCAIt is recognized that detailed test values may not predict nor even correlate with performance of parts molded of these materials.BISO 3167, Type 1B tensile bars, HDPE and MDPE tested at 50 mm/min. For densities 0.925 test at 500 mm/min.CIf a specific value is
13、 required, it must appear on the drawing or contract, or both.DISO 527-1 and ISO 527-2 at 1 mm/min strain rate, chord modulus between 0.05 % and 0.25 % strain.EThere are environmental concerns regarding the disposal of Polyoxyethylated Nonylphenol (Nonylphenoxy poly(ethyleneoxy) ethanol (CAS 68412-5
14、4-4), for example,Igepal CO-630). Users are advised to consult their supplier or local environmental office and follow the guidelines provided for the proper disposal of this chemical.FF50is the time required for failure of 50 % of the samples tested in accordance with Test Method D1693 using undilu
15、ted Igepal CO-630. Mold samples in accordancewith Procedure C of Practice D4703, Annex A1.D7436 1234.1.1 Specific requirements for variations of polyethylenematerials shall be indicated by a six-character designator. Thedesignation will consist of the letter “A” and the five digitscomprising the cel
16、l numbers for the property requirements inthe order as they appear in Table A.4.1.2 Although the values listed are necessary to include therange of properties available in the existing materials, usersshall not assume that every combination of properties areattainable or exist.4.1.3 When the cell de
17、signation is not known or is notrequired, the use of a “0” designation shall be used (see Note6).NOTE 6An example of a high density polyethylene material of thisclassification system is as follows. The designation D7436 PE230A34350would indicate the following material requirements from Table A:PE230
18、 = High Density Polyethylene, from Table PE of this standard,A = Table A for property requirements,3 = tensile strength, 12 MPa, min,4 = tensile break elongation, 400 %, min,3 = tensile modulus, 200 MPa, min,5 = environmental stress-crack resistance, 336 F50hours, min0 = unspecifiedIf no properties
19、are specified, the designation would be D7436PE230A00000.5. Suffixes5.1 When additional requirements are needed that are notcovered by the basic or cell table requirements, they shall beindicated through the use of suffixes. The following suffixesmay be used for specific requirements of the material
20、 for theapplication intended. In general, the suffix letter indicates therequirement needed; the first number (digit) indicates the testcondition, and the second number (digit) indicates the speci-men requirement. The suffixes are as follows:5.1.1 W = Weatherability requirements, as designated bythe
21、 following digits:First Digit0 = To be specified.1 = Specimens exposed to xenon-arc type light source, in accor-dance with Practice D2565, Cycle 1. Specimens shall conform toISO 3167 tensile bars.2 = Specimens exposed to fluorescent-UV-condensation type appa-ratus, in accordance with Practice D4329,
22、 Cycle A. Specimens shallconform to ISO 3167 tensile bars.3 = Specimens exposed to xenon-arc type light source in accor-dance to SAE J2412. (Typically used to represent the effects of ex-posure to window glass filtered solar radiation). Specimens shallconform to ISO 3167 tensile bars.4 = Specimens e
23、xposed to xenon-arc type light source in accor-dance to SAE J2527. (Typically used to represent the effects of di-rect exposure to solar radiation). Specimens shall conform toISO 3167 tensile bars.Second Digit1 = 601.6 kJ/m2 340 nm2 = 1200 kJ/m2 340 nm3 = 2500 kJ/m2 340 nm5.1.1.1 The exposed specime
24、ns shall not exhibit surfacechanges (such as dulling or chalking) or deep-seated changes(such as checking, crazing or warping). The tensile stress atyield after exposure shall be no less than 50 % of the original.5.1.2 P = Impact requirements, Total Energy in Joules atMaximum Load, as designated by
25、the following digits:First Digit0 = To be specified by user.1 = Instrumented impact test in accordance to Practice D3763, 100mm diameter (or 100 mm by 100 mm plaque) by 3.2 mm thick. Testspeed = 2.2 m/s. Conducted at 23C.2 = Instrumented impact test in accordance to Practice D3763, 100mm diameter (o
26、r 100 mm by 100 mm plaque) by 3.2 mm thick. Testspeed = 6.6 m/s. Conducted at 23C.3 = Instrumented impact test in accordance to Practice D3763, 100mm diameter (or 100 mm by 100 mm plaque) by 3.2 mm thick. Testspeed = 2.2 m/s. Conducted at -30C.4 = Instrumented impact test in accordance to Practice D
27、3763, 100mm diameter (or 100 mm by 100 mm plaque) by 3.2 mm thick. Testspeed = 6.6 m/s. Conducted at -30C.Second Digit0 = To be specified by user.1 = 6 Joules, min2 = 9 Joules, min3 = 12 Joules, min4 = 18 Joules, min5 = 21 Joules, min6 = 24 Joules, min7 = 27 Joules, min5.1.3 E = Environmental Stress
28、-Crack Resistance, hours, asdesignated by the following digits:First Digit0 = To be specified by user1 = ESCR in accordance to Test Method D1693 Undiluted surfaceactive agent Igepal CO-630 and a graphical method time of F10.2 = ESCR in accordance to Test Method D1693 Undiluted surfaceactive agent an
29、d a graphical method time of F50.Second Digit0 = To be specified by user1 = 24 hours, min2 = 48 hours, min3 = 96 hours, min4 = 168 hours, min5 = 336 hours, min6 = 672 hours, min7 = 1008 hours, min5.1.4 Z = Other special requirements (for example, internalmold release agent) not covered by existing c
30、allout capabilitiesmay be assigned by the user. These will be spelled out in detailand identified in sequence, that is, 01 UV-stabilized, 02 specialcolor, and 03 etc.5.2 A list of suffixes can also be found in ClassificationD4000 (Table 3) and used for additional requirements, asappropriate. Additio
31、nal suffixes will be added to that classifi-cation system as test methods and requirements are developedand requested.6. Basic Requirements6.1 Basic requirements from property or cell tables, as theyapply, are always in effect unless these requirements aresuperseded by specific suffix requirements,
32、that always takeprecedence.7. Physical Requirements7.1 The color and form of the material shall be as agreedupon between the supplier and the user. Specification changesdue to the effects of colorants shall be noted by both partiesand, when necessary, covered by suffixes.8. Other Requirements8.1 Tes
33、t specimens shall conform to the requirements pre-scribed in Tables PE and Table A and to suffix requirements asthey apply.8.2 Observed or calculated values obtained from analysis,measurement or test, shall be rounded in accordance with theD7436 124rounding method in Practice E29 to the nearest unit
34、 in the lastright-hand place of figures used in expressing the specifiedlimiting value. The value obtained is compared directly withthe specified limiting value. Conformance or nonconformancewith the specification is based on this comparison. See GuideD6436 for reporting properties.9. Sampling9.1 Sa
35、mpling shall be statistically adequate to satisfy therequirements of 13.4.Abatch or lot of resin shall be consideredas a unit of manufacture as prepared for shipment and mayconsist of a blend of two or more production runs of material.10. Specimen Preparation10.1 Unless otherwise specified, plaques
36、shall be preparedin accordance with ISO 293 and ISO 1872-2. Test specimensshall be machined or die cut from the plaques in accordancewith ISO 2818. If insufficient flow or inadequate adhesionbetween particles is observed, materials can be roll milled toensure homogeneity in accordance with Practice
37、D4703, An-nex A1.4. If samples are prepared using roll-milling, it must benoted.10.2 ESCR test specimens shall be prepared in accordancewith Procedure C of Practice D4703.10.3 The specimen thickness shall be 4.0 mm for modulus,tensile and strain testing, 3.2 mm for Condition “A” ESCR andimpact testi
38、ng, and 1.9 mm for Condition “B” ESCR testing.Conditioning shall be as specified in 11.1 and any departurefrom that conditioning shall be reported.11. Conditioning11.1 ConditioningOnce specimens are molded, they shallbe moved to a standard laboratory atmosphere or a controlledlaboratory atmosphere.
39、For natural unfilled polyethylene plas-tics the controlled laboratory atmosphere shall be 23 6 2C.Test specimens shall be conditioned for a minimum of 40 himmediately prior to testing.11.2 Test ConditionsNatural unfilled polyethylene plas-tics shall be tested in a controlled laboratory atmosphere of
40、23 6 2C.12. Test Methods12.1 Determine the properties enumerated in this specifica-tion in accordance with the ISO and ASTM test methods,unless otherwise stated in this specification.12.1.1 Melt Flow RateTest Method in accordance withISO 1133, using condition 190C/21.6 kg or 190C/2.16 kg asspecified
41、 in Table PE, (see Note 7). Make duplicate determi-nations on the material in the form of powder, granules, orpellets. No conditioning is required.NOTE 7Since only condition 190C/2.16 is truly considered “meltindex,” the test in this standard will always be referred to as “Melt FlowRate” as many of
42、the material grades in this document require shear ratevalues that are higher than this to accurately differentiate.12.1.2 DensityTest Method ISO 1183-2. Sample shall bea chip from a molded specimen. The use of an alternativemethod of suitable accuracy is permitted.12.1.3 Tensile Stress at Yield, No
43、minal Strain at BreakTest Method ISO 527-1 and ISO 527-2 at a speed of 50 or 500mm/min as specified in Table PE. Specimens shall conform tothe dimensions given for Type 1B in ISO 527 with thickness of4.0 6 0.2 mm. Die-cut specimens are recommended; however,machine-cut specimens are acceptable. Perce
44、ntage elongationat break shall include the cold-drawing distance. Test resultsfor specimens that break outside the gage marks after extensivecold drawing need not be discarded, unless the break occursbetween the contact surfaces of a grip.12.1.4 Tensile ModulusTest Methods ISO 527-1 andISO 527-2. Us
45、e test speed of 1 mm/min strain rate and reportthe chord modulus between 0.05 % and 0.25 % strain.12.1.5 Environmental Stress-Crack ResistanceTestMethod D1693. The material shall meet the minimum require-ment shown for the appropriate cell classification (in Cell TableA) when tested in accordance wi
46、th Test Method D1693.Polyethylene materials with densities less than or equal to0.925 shall be tested in accordance with Test Method D1693,Condition A. Polyethylenes with densities greater than 0.925shall be tested in accordance to Test Method D1693, ConditionB.NOTE 8The specimen dimensions and notc
47、h depths are different forthese two conditions. An undiluted surface active agent is used for alltesting. An F10or F50time determined in accordance with the graphicalmethod described in Test Method D1693 shall be reported.13. Inspection and Certification13.1 Inspection and certification of the mater
48、ial suppliedunder this specification shall be for conformance to therequirements specified herein.13.2 Lot-acceptance inspection shall be the basis on whichacceptance or rejection of the lot is made. The lot-acceptancetests shall consist of density and melt flow rate, which are thetests typically mo
49、nitored to ensure process control duringmanufacturing. Other certifiable classification properties, in-cluding tensile stress at yield, nominal strain at break, tensilemodulus, and environmental stress-crack resistance, are notconsidered lot acceptance criteria and shall be judged based onthe history of multiple testing on multiple lots.13.3 Periodic check inspection shall consist of the testsspecified for all requirements of the material under thisspecification that are not considered lot-acceptance tests. In-spection frequency shall be adequate to ensure t
