1、Designation: D 4635 08aStandard Specification forPolyethylene Films Made from Low-Density Polyethylene forGeneral Use and Packaging Applications1This standard is issued under the fixed designation D 4635; the number immediately following the designation indicates the year oforiginal adoption or, in
2、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. Scope*1.1 This specification covers unpigmented, unsupported,low-density polyethylene films (
3、hereafter referred to as film orfilms) from Class 1 polyethylenes per Specification D 4976.NOTE 1The density of a film will not necessarily be equal to thedensity of a molded plaque from the same resin.NOTE 2Blends of ethylene/vinylacetate (EVA) with low-density poly-ethylene may have densities up t
4、o 0.929 g/cm3.1.2 This specification is applicable to homopolymer poly-ethylene, but is not restricted to it. It is applicable to films madefrom polyethylene copolymers, and also applicable to filmsmade from blends of homopolymers and copolymers, includ-ing ethylene/vinylacetate copolymers.1.3 The t
5、hickness of the films covered by this specificationis 100 m or less (0.004 in. or less), inclusive. The maximumwidth of the sheet or layflat is 3.00 m (120 in.).1.4 This specification does not cover oriented heat-shrinkable films.1.5 This specification allows for the use of recycled poly-ethylene fi
6、lm or resin as feedstock, in whole or in part, as longas all of the requirements of this specification are met and aslong as any specific requirements as governed by the producerand end user are also met. (See Note 3.)NOTE 3Guide D 7209 describes terminology and definitions relatedto recycled plasti
7、cs.1.6 This specification defines the levels of the variousphysical properties from which specifications for specific filmsmay be described. The levels of physical properties required bya film for a given application are selected from Section 6.However, Sections 2-5 relating to tolerances shall appl
8、ywithout change to all film falling within the scope indicated bythe title and 1.1-1.4.1.7 This specification covers dimensional tolerances, clas-sifications, intrinsic quality requirements, and test methods.The dimensional tolerances include thickness, width, andlength or yield. Classification defi
9、nes types, classes, surfaces,and finishes. The intrinsic quality requirements include density,workmanship, tensile strength, heat sealability, and odor, aswell as the classification properties for impact strength, coef-ficient of friction, optical properties, and surface treatment. Asampling method
10、is included.1.8 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.9 The following precautionary caveat pertains only to thetest methods portion, Section 10, of this specification: Thisstandard does not purport to address all of
11、 the safety concerns,if any, associated with 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.NOTE 4There is no similar or equivalent ISO specification.2. Referenc
12、ed Documents2.1 ASTM Standards:2D 618 Practice for Conditioning Plastics for TestingD 882 Test Method for Tensile Properties of Thin PlasticSheetingD 883 Terminology Relating to PlasticsD 1003 Test Method for Haze and Luminous Transmittanceof Transparent PlasticsD 1505 Test Method for Density of Pla
13、stics by the Density-Gradient TechniqueD 1709 Test Methods for Impact Resistance of Plastic Filmby the Free-Falling Dart MethodD 1984 Specification for Tall Oil Fatty Acids3D 2103 Specification for Polyethylene Film and SheetingD 2457 Test Method for Specular Gloss of Plastic Films andSolid Plastics
14、D 2578 Test Method for Wetting Tension of Polyethyleneand Polypropylene FilmsD 4321 Test Method for Package Yield of Plastic FilmD 4703 Practice for Compression Molding Thermoplastic1This specification is under the jurisdiction of ASTM Committee D20 onPlastics and is the direct responsibility of Sub
15、committee D20.19 on Film andSheeting.Current edition approved Nov. 1, 2008. Published November 2008. Originallyapproved in 1986. Last previous edition approved in 2008 as D 4635 - 08.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.
16、org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn1*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, U
17、nited States.Materials into Test Specimens, Plaques, or SheetsD 4976 Specification for Polyethylene Plastics Molding andExtrusion MaterialsD 7209 Guide for Waste Reduction, Resource Recovery,and Use of Recycled Polymeric Materials and ProductsE 1870 Test Method for Odor and Taste Transfer fromPolyme
18、ric Packaging FilmF88 Test Method for Seal Strength of Flexible BarrierMaterialsNOTE 5If this product is intended for packaging foods, medicines,drugs, and cosmetics, it is subject to applicable regulations of the Foodand Drug Administration or the Department of Agriculture and mustcomply with such
19、regulations. If it is necessary to comply with regulationsof other government agencies, such as the Consumer Product SafetyCommission, Environmental Protection Agency, Department of Transpor-tation, Federal Trade Commission, or others, such compliance should bearranged between the buyer and the sell
20、er prior to placing an order.3. Terminology3.1 DefinitionsUnless otherwise indicated, the terminol-ogy used in this specification is in accordance with Terminol-ogy D 883.4. Classification4.1 The low-density polyethylene film is, by this specifica-tion, classified by Types 1, 2, and 3; Surfaces 1, 2
21、, and 3;Classes 1, 2, 3, and 4; and Finishes 1, 2, 3, and 4. Theseclassifications are described in detail in 6.1.5. Materials5.1 The film shall be made from an ethylene homopolymer,ethylene copolymers, or blends of homopolymers or copoly-mers, or homopolymer and copolymer, so that it meets thedensit
22、y and other film requirements listed herein.5.2 The film shall be made from resins having densitiesbetween 910.0 and 925.0 kg/m3(0.910 and 0.925 g/cm3),inclusive. This is the range of standard densities in thedefinition of low-density polyethylene (see TerminologyD 883). Standard density refers to t
23、he density of the materialmolded to a thickness of 1.9 mm (0.075 in.) using Procedure Cof Annex A1 of Practice D 4703 (see Note 1).5.3 The film shall be natural in color (essentially colorless).6. Physical Requirements Physical Requirements6.1 Classification Properties:6.1.1 TypeThe dart drop impact
24、 for all thickness of filmshall be as specified in Table 1 for Types 1, 2, and 3.6.1.2 SurfaceThe kinetic coefficient of friction shall be asspecified in Table 2 for Surfaces 1, 2, and 3.6.1.3 ClassThe optical properties shall be as specified inTable 3 for Classes 1, 2, and 3. The optical properties
25、 of glossand haze do not always correlate. The particular property ofmost importance for the specific application shall be estab-lished, and the value for this property shall then govern in caseof any inconsistency.6.1.4 FinishThe surface treatment level of the film shallbe as specified in Table 4 f
26、or Finishes 1, 2, 3, and 4.6.2 Other Properties:6.2.1 Tensile PropertiesThe tensile strength and elonga-tion at break for all thicknesses shall be as specified in Table 5.6.2.2 Heat SealabilityThe minimum ratio of heat-sealstrength to the film strength in the two principal directions shallbe as spec
27、ified in Table 6.6.2.3 OdorThe odor level of the film shall average nomore than a 3.5 rating level.7. Dimensions7.1 SizeThe nominal thickness, width, length per roll orroll diameter, and yield of the film shall be established bymutual agreement between the purchaser and the supplier.7.2 Thickness To
28、leranceThe thickness variation acrossthe film shall be within the tolerances given in Table 7.7.3 Width ToleranceThe width shall be within the toler-ances given in Table 8.7.4 Yield ToleranceThe deviation of the actual yield fromnominal yield shall be within the tolerances given in Table 9.7.5 Flatn
29、essThe flatness of the film shall be within limitsas mutually agreed upon between the buyer and the seller.7.6 Dimension tolerances for “J-Sheeting” lip and gussetdepth shall be established by mutual agreement between thepurchaser and the supplier.8. Workmanship, Finish, and Appearance8.1 FilmThe fi
30、lm shall have workmanship qualities con-forming to good commercial practice. The quality of film withregard to gels, streaks, pinholes, particles of foreign matter,scratches, wrinkles, wind chatter, undispersed raw materials,holes, tears, and blisters shall be mutually established by thepurchaser an
31、d the supplier.8.2 Roll Formation:8.2.1 The diameter of cores upon which film is wound shallbe established by mutual agreement between the purchaser andthe supplier. Cores upon which film is wound must not berecessed at either edge of the roll, but may extend up to 6 mm(14 in.) beyond either edge of
32、 the roll. Rolls with cores that arecrushed and are not able to be mounted on the purchasersequipment are to be considered rejects.8.2.2 Ridges and soft spots which result in bagginess andlooseness of the unwound film are unacceptable and may beTABLE 1 Classification for TypeFilm ThicknessDrop Dart
33、(g, min)AType 1 Type 2 Type 30.52 0.2to0.53 0.2 or lessD 4635 08a2rejected by the purchaser on a roll-to-roll basis if the conditionscontribute to poor performance of the film in end-use applica-tion.8.2.3 The edges of the roll must be free of nicks and cuts,and the general condition of roll edges m
34、ust not interfere withthe unwinding of the rolls.8.2.4 The type and number of splices, flaggings of splices,or breaks (if unspliced) in rolls of more than one piece shall beestablished by mutual agreement between the supplier and thepurchaser.9. Sampling9.1 Statistically based sampling plans which a
35、re appropriatefor each particular product or quantity may be used to obtainsamples for use in determining compliance with this specifi-cation.9.2 For the purposes of developing supplier-purchaserspecifications, a lot size generally refers to the number of rollsin a lot. Sampling units are those roll
36、s selected by randomnumbers from the lot. A unit sample is the sample of film takenfrom the roll. Care must be exercised in taking unit samples.Unwind and then discard several turns from the roll and thentake more than enough sample to run all specified tests. Keepthe sample from becoming soiled. En
37、sure that the sample is notfolded or creased excessively.10. Test Methods10.1 ConditioningCondition the test specimens at 23 62C (73.4 6 3.6F) for not less than 40 h prior to test, inaccordance with Specification D 4976 or as otherwise specifiedby agreement. In cases of disagreement, the tolerances
38、shall be61C (61.8F).10.2 Test ConditionsConduct the tests at 23 6 2C (73.46 3.6F) in accordance with Specification D 4976 or asotherwise specified by agreement. In cases of disagreement, thetolerances shall be 61C (61.8F).10.3 In addition, for films containing hydrophilic fillers,co-monomers, pigmen
39、ts or other modifiers, conditioning andtesting shall be done at 50 6 10 % relative humidity. In casesof disagreement, the tolerance shall be 65 % relative humidity.10.4 WidthMeasure width with a metal rule capable ofmeasuring to an accuracy of 61mm(116 in.).10.5 ThicknessMeasure thickness in accorda
40、nce with theGeneral Test Methods section of Specification D 2103, with themodification that the specimen shall be taken as a 50-mm(2-in.) strip across the web and measured at intervals of notmore than 50 mm.10.6 YieldSee Test Method D 4321.10.7 FlatnessMeasure flatness using a method mutuallyagreed
41、upon between the purchaser and the supplier.10.8 DensityThe density of resins from which the film ismade shall be measured in accordance with Test MethodD 1505.10.9 Coeffcient of FrictionThe kinetic coefficient of fric-tion shall be measured in accordance with Test MethodD 1894. The test shall be co
42、nducted film to film, in both themachine direction and transverse direction.10.10 Optical Properties:10.10.1 ClarityMeasure clarity of the film by visual orinstrumented means, as agreed upon between the purchaser andthe supplier.10.10.2 GlossMeasure gloss of the film in accordancewith Test Method D
43、2457, using a 45 gloss head.10.10.3 HazeMeasure haze in accordance with TestMethod D 1003.10.11 Wetting TensionMeasure wetting tension in accor-dance with Test Method D 2578.10.12 Impact ResistanceMeasure impact resistance inaccordance with Test Methods D 1709, except that TestMethod A shall be used
44、 for all gages of film.10.13 Tensile PropertiesMeasure tensile strength andelongation at break in accordance with Test Methods D 882.10.14 Heat SealabilityMeasure heat sealability in accor-dance with Test Methods F88, Test Method B, Dynamic LoadTest.10.15 OdorMeasure odor level in accordance with Te
45、stMethod E 1870, low to moderate scale.11. Inspection and Certification11.1 Inspection and certification of the material suppliedunder this specification shall be for conformance to therequirements specified herein.TABLE 3 Optical Properties for ClassesClass Gloss Units Haze, %1 30 or less 252 30 to
46、 50 10 to 253 50 to 70 5 to 104 70 0to5TABLE 4 Classification for FinishFinishWetting Tension, mN/m(dynes/cm)1 32, 33, 342 35, 36, 373 38, 39, 404 41 and overTABLE 5 Tensile PropertiesProperty UnitsMachineDirectionTransverseDirectionTensile Strength, min MPa (psi) 11.7 (1700) 8.3 (1200)Tensile Elong
47、ation, min % 225 350TABLE 6 Heat SealabilityAFinish ofContact SurfacesBHeat Sealability,min2to2 0.601to2 0.601to1 0.75AHeat sealability is the ratio of the tensile strength of the heat-sealed specimento the tensile strength of the original film specimen.BHeat sealability is not applicable to films w
48、ith finish greater than two; this doesnot infer that films with finishes greater than two cannot be sealed.D 4635 08a311.2 Lot-acceptance inspection shall be the basis on whichacceptance or rejection of the lot is made. The lot-acceptanceinspection shall consist of those tests that ensure processcon
49、trol during manufacture as well as those necessary to ensurecertification in accordance with 11.4.11.3 Periodic check inspection shall consist of the testsspecified for all requirements of the material under thisspecification. Inspection frequency shall be adequate to ensurethat the material is certifiable in accordance with 11.4.11.4 Certification shall be that the material was manufac-tured, sampled, tested, and inspected in accordance with thisspecification and that average values meet the requirements ata confidence level of 95 %.
