1、Designation: D4976 12Standard Specification forPolyethylene Plastics Molding and Extrusion Materials1This standard is issued under the fixed designation D4976; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.INTRODUCTIONThis specification is not intended for the selec
3、tion of materials, but only as a means to call outplastic materials to be used for the manufacture of parts. The selection of these materials is to be madeby personnel with expertise in the plastics field where the environment, inherent properties of thematerials, performance of the parts, part desi
4、gn, manufacturing process, and economics areconsidered. This specification does not specify the source of the resin to be used for the fabricationof any given article.1. Scope*1.1 This specification provides for the identification ofpolyethylene plastics molding and extrusion materials in sucha mann
5、er that the supplier and the user can agree on theacceptability of different commercial lots or shipments. Thetests involved in this specification are intended to provideinformation for identifying materials in accordance with thegroups, classes, and grades covered. It is not the function ofthis spe
6、cification to provide specific engineering data fordesign purposes.1.2 Other requirements may be necessary to identify par-ticular characteristics important to specialized applications.These shall be agreed upon between the user and the supplier,by using the suffixes given in Section 1.3.1.3 Ethylen
7、e plastic materials, being thermoplastic, arereprocessable and recyclable (see Note 1). This specificationallows for the use of those ethylene plastic materials, providedthat any specific requirements as governed by the producer andthe end user are met.NOTE 1See Guide D5033 for information and defin
8、itions related torecycled plastics.1.4 The values stated in SI units are regarded as standard.1.5 The following precautionary caveat pertains to the testmethod portion only, Section 12, of this specification. Thisstandard does not purport to address all of the safety concerns,if any, associated with
9、 its use. It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.1.6 For information regarding plastic pipe materials seeSpecification D3350. For information regarding wire and c
10、ablematerials, see Specification D1248. For information on poly-ethylenes with densities below 0.910 g/cm3, see ClassificationD5593.NOTE 2There is no similar or equivalent ISO standard.2. Referenced Documents2.1 ASTM Standards:2D257 Test Methods for DC Resistance or Conductance ofInsulating Material
11、sD568 Method of Test for Rate of Burning and/or Extent andTime of Burning of Flexible Plastics in a Vertical PositionD618 Practice for Conditioning Plastics for TestingD635 Test Method for Rate of Burning and/or Extent andTime of Burning of Plastics in a Horizontal PositionD638 Test Method for Tensi
12、le Properties of PlasticsD790 Test Methods for Flexural Properties of Unreinforcedand Reinforced Plastics and Electrical Insulating MaterialsD792 Test Methods for Density and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD883 Terminology Relating to PlasticsD1238 Test Method for Me
13、lt Flow Rates of Thermoplasticsby Extrusion PlastometerD1248 Specification for Polyethylene Plastics Extrusion1This specification is under the jurisdiction of ASTM Committee D20 onPlastics and is the direct responsibility of Subcommittee D20.15 on ThermoplasticMaterials.Current edition approved Apri
14、l 1, 2012. Published May 2012. Originallyapproved in 1995. Last previous edition approved in 2006 as D4976 - 06. DOI:10.1520/D4976-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume info
15、rmation, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Materials for Wire and CableD1505 Test Method
16、for Density of Plastics by the Density-Gradient TechniqueD1531 Test Methods for Relative Permittivity (DielectricConstant) and Dissipation Factor by Fluid DisplacementProceduresD1600 Terminology for Abbreviated Terms Relating toPlasticsD1693 Test Method for Environmental Stress-Cracking ofEthylene P
17、lasticsD1898 Practice for Sampling of Plastics3D2565 Practice for Xenon-Arc Exposure of Plastics In-tended for Outdoor ApplicationsD2839 Practice for Use of a Melt Index Strand for Deter-mining Density of PolyethyleneD2951 Test Method for Resistance of Types III and IVPolyethylene Plastics to Therma
18、l Stress-Cracking3D3350 Specification for Polyethylene Plastics Pipe andFittings MaterialsD3892 Practice for Packaging/Packing of PlasticsD4000 Classification System for Specifying Plastic Materi-alsD4703 Practice for Compression Molding ThermoplasticMaterials into Test Specimens, Plaques, or Sheets
19、D4883 Test Method for Density of Polyethylene by theUltrasound TechniqueD5033 Guide for Development of ASTM Standards Relat-ing to Recycling and Use of Recycled Plastics3D5593 Classification for Thermoplastic ElastomersOlefinic (TEO)3E29 Practice for Using Significant Digits in Test Data toDetermine
20、 Conformance with SpecificationsF1473 Test Method for Notch Tensile Test to Measure theResistance to Slow Crack Growth of Polyethylene Pipesand ResinsG23 Practice for Operating Light-Exposure Apparatus(Carbon-Arc Type) With and Without Water for Exposureof Nonmetallic Materials (Discontinued 2001)3G
21、53 Practice for Operating Light-and Water-Exposure Ap-paratus (Fluorescent UV-Condensation Type) for Exposureof Nonmetallic Materials (Discontinued 2001)32.2 Military Standard:MIL-STD-105 Sampling Procedures and Tables for Inspec-tion by Attributes42.3 DOT Standard:Federal Motor Vehicle Safety Stand
22、ard 302, Flammabilityof Interior Materials53. Terminology3.1 DefinitionsFor definitions of technical terms pertain-ing to plastics used in this specification, see Terminology D883and Terminology D1600.3.2 Historical usage and user group conventions have re-sulted in inconsistent terminology used to
23、categorize anddescribe polyethylene resins and compounds. The followingterminology is in use in ASTM specifications pertaining topolyethylene:3.2.1 Specification D1248:3.2.1.1 Type (I, II, III, IV) = density ranges (same, respec-tively, as Classes 1, 2, 3, and 4 in Specification D4976).3.2.1.2 Class
24、 (A, B, C, D) = composition and use.3.2.1.3 Category (1, 2, 3, 4, 5) = melt index ranges (same asGrade in Specification D4976).3.2.1.4 Grade (E, J, D, or W followed by one or two digits)= specific requirements from tables.3.2.2 Specification D3350:3.2.2.1 Type (I, II, III) = density ranges (same as
25、Types I, II,and III in Specification D1248 and Classes 1, 2, and 3 inSpecification D4976).3.2.2.2 Class = a line callout system consisting of “PE”followed by six cell numbers from Table 1 plus a letter (A, B,C, D, E) denoting color and UV stabilizer.3.2.2.3 Grade = simplified line callout system usi
26、ng “PE”followed by density and slow crack growth cell numbers fromTable 1.3.2.3 Specification D4976:3.2.3.1 Group (1, 2) = branched or linear polyethylene.3.2.3.2 Class (1, 2, 3, 4) = density ranges (same, respec-tively, as Types I, II, III, and IV in Specification D1248).3.2.3.3 Grade (1, 2, 3, 4,
27、5) = melt index ranges (same asCategory in Specification D1248).4. Classification4.1 Unreinforced polyethylene plastic materials are classi-fied into groups in accordance with molecular structure. Thesegroups are subdivided into classes and grades as shown inTable PE (Basic Property Table).3Withdraw
28、n. The last approved version of this historical standard is referencedon www.astm.org.4Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.5Available from United States Department of Transportation, National HighwayTraffic
29、 Safety Administration, Office of Public Affairs and Consumer Participation,400 7th St., SW, Washington, DC 20590.D4976 122TABLE PE Basic Requirement of Polyethylene PlasticsGroup Description Class Description GradeFlow Rate, D1238,g/10 minTensile Stress at Yield,D638,min,MPaNominal Strain atBreak,
30、D638,min,%Flexural Modulus at2 % Strain, D790, min,MPa1 Branched 1 low density 1 25 8 70 100. . . 2 10 to 25 8 90 1250.9100.925 3 1 to 10 8.5 100 125. . . 4 0.4 to 1 9.5 300 125. . . 5 to 0.4 9.5 400 150. 0 . . . .2 medium density 1 25 8 40 200. . . 2 10 to 25 11 50 2000.9250.940 3 1 to 10 11 70 200
31、. . . 4 0.4 to 1 11 200 250. . . 5 to 0.4 12 400 300. 0 . . . .0 . 0 . . . .2 Linear 1 low density 1 25 10 300 300. . . 2 10 to 25 10 300 3250.9100.925 3 1 to 10 10 300 350. . . 4 0.4 to 1 10 400 350. . . 5 to 0.4 12 500 400. 0 . . . .2 medium density 1 25 14 90 500. . . 2 10 to 25 14 100 5000.9250.
32、940 3 1 to 10 14 100 550. . . 4 0.4 to 1 15 200 600. . . 5 to 0.4 19 400 600. 0 . . . .3 high density 1 25 17 10 400. . . 2 10 to 25 17 50 4000.a9400.960 3 1 to 10 18 200 450. . . 4 0.4 to 1 19 400 500. . . 5 to 0.4 20 600 600. 0 . . . .4 high density 1 25 24 10 500. . . 2 10 to 25 24 10 6000.960 3
33、1 to 10 25 30 800. . . 4 0.4 to 1 28 300 900. . . 5 to 0.4 28 400 1000. 0 . . . .0 0 . 0 . . . .Cell Table A Detail Requirements for Polyethylene PlasticsDesignation Or-der NumberPropertyCell Limits0 12345678 91 Tensile Stress at Yield, Test Method D638, MPa, min unspecified 4 8 12 16 21 30 35 . . .
34、 specify value2 Nominal Strain at Break, Test Method D638, %, min unspecified 25 50 200 400 600 800 1000 . . . specify value3 Secant Flexural Modulus at 2 % Strain, D790, MPa, min unspecified 50 100 200 400 600 800 1000 . . . specify value4 Thermal stress-crack resistance, D2951, hours without crack
35、-ing, minunspecified 24 48 96 168 . . . . . . . . . . . . specify value5 Environmental stress-crack resistance, D1693, min F50, h unspecified 24 48 96 168 336 672 1008 . . . specify valueCell Table B Detail Requirements for Polyethylene PlasticsDesignation Or-der NumberPropertyCell Limits0 12345678
36、91 Tensile Stress at Yield, D638, MPa, min unspecified 4 8 12 16 21 30 35 . . . specify value2 Nominal Strain at Break, D638, %, min unspecified 25 50 200 400 600 800 1000 . . . specify value3 Secant Flexural Modulus at 2 % Strain, D790, MPa, min unspecified 50 100 200 400 600 800 1000 . . . specify
37、 value4 Thermal stress-crack resistance, D2951, hours without crack-ing, minunspecified 24 48 96 168 . . . . . . . . . . . . specify value5 Slow Crack Growth Resistance, PENT-Test Method F1473,h,minunspecified 0.3 1 3 10 30 100 300 . . . specify valueD4976 123NOTE 3An example of this classification
38、system is as follows: Thedesignation PE 112 would indicate PE, polyethylene as found in Termi-nology D1600, 1 (group) branched, 1 (class) low density, 2 (grade) 25melt index.4.2 Cell Tables A or B shall be used to specify the physicalproperty requirements that shall be shown by a five-digitdesignati
39、on. The designation shall consist of the letter A andthe five digits comprising the cell numbers for the propertyrequirements in the order they appear in Cell Table A.4.2.1 Although the values listed are necessary to include therange of properties available in the existing materials, usersshould not
40、 infer that every possible combination of theproperties exist or can be obtained.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.Similar
41、ly, there are other polyethylene plastics of very high molecularweight having densities slightly less than 0.941 that, in all other respects,are more characteristic 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 d
42、ensity,Class 2 (0.925 to 0.940) = medium density,Class 3 (0.940 to 0.960) = high density,Class 4 (0.960) = high density, andWhile Class 3 has been divided into two ranges of density, (Classes 3 and4), both are still described by the term “high density.”5. Suffixes5.1 When using the call-out for the
43、materials covered by thisspecification, the following suffixes may be used for specificrequirements of the material for the application intended. Ingeneral, the suffix letter indicates the requirement needed; thefirst number (digit) indicates the test condition, and the secondnumber (digit) indicate
44、s the specimen requirement. The suf-fixes are as follows:5.1.1 E = Electrical requirements as designated by thefollowing digits:First Digit0 =To be specified by user.1 =Specimens preconditioned 40 h at 23C and 50 % relative humidity,then 14 days in distilled water at 23 6 1C.Second Digit0 =To be spe
45、cified by user.1 =Volume resistivity, permittivity, and dissipation factor meet propertylimits as shown as follows. These are electrical limits usually appliedto unreinforced polyethylene plastics when control of their electricalproperties is required.Electrical Properties:TestMethodsPermittivity, m
46、ax D1531 2.30Dissipation factor, max D1531 0.001Volume resistivity, minV-cmD257 1 3 1015Water immersion stability D1531 shall meet the dielectricconstant and dissipationfactor requirements5.1.2 F = Flammability requirements6as designated by thefollowing digits:First digit0 = To be specified by user.
47、1 = Product is 3.05-mm thickness, min.2 = Product is 1.47-mm thickness, min.3 = Product is 0.71-mm thickness, min.4 = Product is 0.38-mm thickness, min.5 = Motor Vehicle Safety Standard 302.Second Digit0 = To be specified by user.1 = When burned horizontally in accordance with Test Method D635, a ma
48、te-rial:(a)Does not have a burning rate exceeding 38.1 mm/min over a 76.2-mmspan for specimens of 3.05 to 12.7-mm thickness; or(b)Does not have a horizontal burning rate exceeding 76.2 mm/min over a76.2-mm span for specimens of less than 3.05-mm thickness; or(c) Ceases to burn, horizontally, before
49、the 102-mm reference mark.2 = When burned vertically in accordance with Test Method D568, the mate-rial:(a)Does not have any specimens that burn with flaming combustion formore than 30 s after two applications of the test flame:(b)Does not have a total flaming combustion time exceeding 250 s for 10flame applications for each set of five specimens;(c)Does not have any specimens that burn with flaming or glowing com-bustion up to the holder clamp;(d)Has specimens that drip flaming particles that ignite the dry absorbentsurgical cotton placed 305 mm 12 in. below the tes
