1、Designation: D6338 10D6338 17Standard Classification System forHighly Crosslinked Thermoplastic Vulcanizates(HCTPVs)(HCTPV) Based on ASTM Standard Test Methods1This standard is issued under the fixed designation D6338; the number immediately following the designation indicates the year oforiginal ad
2、option 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 classification system is intended as a means for the callout of m
3、aterials for the fabrication ofparts or end-use items. It is not intended for material selection, which should be performed by thosewith special expertise in the materials field. Material selection should be made after carefulconsideration of: part performance and design; the environment in which th
4、e part must function; thematerial properties covered and not covered by this classification system; the desired service lifetimeof the part; the fabrication process for the part; and material and fabrication costs.1. Scope*1.1 This classification system covers highly crosslinked thermoplastic vulcan
5、izates (HCTPVs)(HCTPV) for extrusion, moldingand other fabrication methods. HCTPVs Highly crosslinked thermoplastic vulcanizates (HCTPV) are thermoplastic elastomers(TPEs)(TPE) consisting of two or more polymer systems at least one of which is rubbery and highly (95 %) crosslinked and atleast one of
6、 which is thermoplastic, with each system having its own phase. The thermoplastic phase will tend to be continuousand the rubbery phase discontinuous. The high level of crosslinking and ultrafine particle size (ca 1 m diameter) of the rubberyphase give rise to properties more closely approaching tho
7、se of conventional thermoset rubber, when compared to the samethermoplastic/rubbery polymer composition with a lower level (95 %) of crosslinking. The HCTPV polymer compositions maycontain fillers, reinforcing agents, plasticizers, resins, antidegradants, colorants and other beneficial constituents.
8、 RecycledHCTPVsHCTPV are not covered in this classification system.1.2 Included The properties included in this classification system are the properties standard are those required to identify thecompositions covered. Other requirements necessary to identify the respective compositions. For speciali
9、zed applications, otherrequirements may be needed to identify specific characteristics.particular characteristics important to specialized applications areto be specified by using suffixes as given in Section 5.1.3 This classification system and subsequent line callout (specification) are intended t
10、o provide a means of calling out plasticmaterials used in the fabrication of end items or parts. It is not intended for the selection of materials. Material selection can bemade by those having expertise in the plastic field only after careful consideration of the design and the performance required
11、 ofthe part, the environment to which it will be exposed, the fabrication process to be employed, the costs involved, and the inherentproperties of the material other than those covered by this standard.1.4 As given in IEEE/ASTM SI-10, values in SI units are to be regarded as standard.NOTE 1There is
12、 no known ISO equivalent to this standard.1.5 This standard is based on testing completed in accordance with ASTM standard test methods.1.6 The following safety hazards caveat pertains only to the test methods portion, Section 1211, of this classification system.Thisstandard does not purport to addr
13、ess all of the safety problems,concerns, if any, associated with its use. It is the responsibility ofthe user of this standard to establish appropriate safety safety, health and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.7 This international
14、 standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.1
15、This specification is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials.Current edition approved Aug. 1, 2010Aug. 1, 2017. Published September 2010August 2017. Originally approved in 1998. Last previous edition
16、 approved in 20092010as D6338 - 09.D6338 - 10. DOI: 10.1520/D6338-10.10.1520/D6338-17.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to
17、adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright A
18、STM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12. Referenced Documents2.1 ASTM Standards:2D395 Test Methods for Rubber PropertyCompression SetD412 Test Methods for Vulcanized Rubber and Thermoplastic ElastomersTensionD471 Test Method for Rubber
19、 PropertyEffect of LiquidsD573 Test Method for RubberDeterioration in an Air OvenD618 Practice for Conditioning Plastics for TestingD638 Test Method for Tensile Properties of PlasticsD883 Terminology Relating to PlasticsD1434 Test Method for Determining Gas Permeability Characteristics of Plastic Fi
20、lm and SheetingD1566 Terminology Relating to RubberD2240 Test Method for Rubber PropertyDurometer HardnessD3182 Practice for RubberMaterials, Equipment, and Procedures for Mixing Standard Compounds and Preparing StandardVulcanized SheetsD3892 Practice for Packaging/Packing of PlasticsD4000 Classific
21、ation System for Specifying Plastic MaterialsD6869 Test Method for Coulometric and Volumetric Determination of Moisture in Plastics Using the Karl Fischer Reaction (theReaction of Iodine with Water)E29 Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationsIEE
22、E/ASTM SI-10 Standard for Use of the International System of Units (SI): The Modern Metric System3. Terminology3.1 DefinitionsExcept for the terms defined below, technical terms pertaining to materials covered by this classification systemare given in Terminologies D883 and D1566.3.2 Definitions of
23、Terms Specific to This Standard:3.2.1 dynamic vulcanization, nthe process of intimate melt mixing a thermoplastic polymer with a suitably reactive rubberypolymer to generate a thermoplastic elastomer with a chemically crosslinked rubbery phase, resulting in properties closer to thoseof a thermoset r
24、ubber when compared to the same uncrosslinked composition.3.2.2 thermoplastic elastomer (TPE), na diverse family of rubberlike materials that, unlike conventional vulcanized rubbers,can be reprocessed and recycled like thermoplastic materials.3.2.3 thermoplastic vulcanizate (TPV), na thermoplastic e
25、lastomer with a chemically crosslinked rubbery phase, produced bythe dynamic vulcanization.4. Classification4.1 Highly crosslinked thermoplastic vulcanizates are classified into groups according to the rubbery polymer(s) present. Thesegroups are subclassified into classes and grades as shown in Tabl
26、e HCTPV.4.1.1 To illustrate this classification system: the designation HCTPV 0121 would indicate HCTPV = highly crosslinkedthermoplastic vulcanizate, 01 (group) = EPDM rubber 95 % crosslinked, 2 (class) = medium hardness, and 1 (grade) meeting therequirements in Table HCTPV.4.1.2 To enable the inco
27、rporation of special or future materials, the “Other” category (0) for group, class and grade is given inTable HCTPV. Basic properties can be obtained from Table A.4.2 There is no distinction between reinforced and unreinforced highly crosslinked thermoplastic vulcanizates.4.1 Asix-character designa
28、tion shall show the specific requirements for the HCTPVs. This designation shall consist of the letterA and five digits comprising the property requirements in the order they appear in Table A.Highly crosslinked thermoplasticvulcanizates are classified into groups according to the rubbery polymer(s)
29、 present. These groups are subclassified into classes andgrades as shown in Table HCTPV.4.1.1 To illustrate this classification system: the designation HCTPV 0121 would indicate HCTPV = highly crosslinkedthermoplastic vulcanizate, 01 (group) = EPDM rubber 95 % crosslinked, 2 (class) = medium hardnes
30、s, and 1 (grade) meeting therequirements in Table HCTPV.4.1.2 To enable the incorporation of special or future materials, the “Other” category for group (00), class (0), and grade (0)is shown in Table HCTPV. Basic properties are to be obtained from Table A.4.1.2.1 Although the values listed are nece
31、ssary to include the range of properties available in existing materials, not everypossible combination of the properties exists or can be obtained.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standar
32、dsvolume information, refer to the standards Document Summary page on the ASTM website.D6338 1724.1.3 There is no distinction between reinforced and unreinforced highly crosslinked thermoplastic vulcanizates.4.1.4 Asix-character designation shall show the specific requirements for the HCTPV in the “
33、Other” category. This designationshall consist of the letter A and five digits comprising the property requirements in the order they appear in Table A.4.1.5 The following is an example of this classification system: Designation HCTPV 0110A45643 indicates the following, withthe Table A requirements:
34、where:HCTPV 0110 = fully crosslinked thermoplastic vulcanizate, based on EPDM rubber 95 % crosslinked, low hardness fromTable HCTPV,A = Table A property requirements,4 = 65 6 5 Shore A hardness, Test Method D2240, 5 s delay,5 = 14 MPa, tensile strength, min, Test Method D412 at 23C,6 = 6.0 MPa, tens
35、ile strength, min, Test Method D412 at 100C,4 = 80 %, weight change, max, Test Method D471, IRM 903 oil, 24 h/121C, and3 = 30 %, compression set, max, Test Method D395, Procedure B, 22 h/100C.The designation HCTPV 0100 would indicate no properties being specified.4.1.6 Although the values listed are
36、 necessary to include the range of properties available in existing materials, users should notinfer that every possible combination of the properties exists or can be obtained.If no properties are specified, the designationwould be HCTPV 0110 A00000.5. Suffixes5.1 Necessary requirements for superse
37、ding or supplementing the property-table or cell-table requirements shall be specifiedwith suffixes. The first suffix letter indicates the special requirements needed; the second letter indicates the test method orconditions, or both, with a three-digit number indicating the specific requirements. P
38、ermissible suffixes are listed in Table 3 ofClassificationWhen additional requirements are needed that are not covered by the basic requirements or cell-table requirements,they shall be indicated through the use of suffixes. D4000.5.1.1 A list of suffixes can be found in Classification System D4000
39、(Table 3) and are to be used for additional requirementsas appropriate. Additional suffixes will be added to this specificationthat standard as test requirementsmethods and methodsre-quirements are developed or requested, or both.and requested.6. BasicGeneral Requirements6.1 Basic requirements from
40、the property tables or cell tables are always in effect,effect unless superseded by specific suffixrequirements, which always take precedence.6.2 The plastics composition shall be uniform and shall conform to the requirements specified herein.7. General Requirements7.1 Material composition shall be
41、uniform and shall conform to the requirements of this specification. The product form andcolor of the HCTPVs shall be mutually agreed to by the parties involved.7. Detail Requirements7.1 Test specimens and their preparation The materials shall conform to Table HCTPV and Table the requirements in Tab
42、lesHCTPV, A, and applicable suffix requirements.suffix requirements as they apply.7.2 For purposes of determining conformance, all specified limits for a specification (line call out) callout) based on thisclassification system are absolute limits, as defined in Practice E29.7.2.1 With the absolute
43、method, an observed value or a calculated value using the number of significant figures, as specifiedby the test method used in determining the value, is not rounded, but is to be compared directly with the limiting value.Conformance or nonconformance is based on this comparison.8. Sampling8.1 Sampl
44、ing shall be statistically adequate to satisfy the requirements of 12.4.8.2 Sampling shall be statistically adequate to satisfy the requirements of Section 13. A unit of manufacture for shipment shallbe a production lot of HCTPV or a uniformly mixed blend of two or more such production lots.9. Speci
45、men Preparation9.1 Test specimens shall be prepared by a rigorously specified injection molding process, unless specifically mentioned to thecontrary. This process shouldprocess. This process shall be as specified in Practice D3182, or as specified by the HCTPV supplier,with due regard given to the
46、anisotropic nature of HCTPV molded parts.D6338 17310. Conditioning10.1 Prior to testing, test specimens shall be conditioned in the standard laboratory atmosphere in accordance with ProcedureA of Practice D618.10.2 Tests shall be carried out at 23 6 2C and 50 6 10 % relative humidity, in accordance
47、with Practice humidity.D618.11. Test Methods11.1 Properties covered by this classification shall be measured by the following Test Methods, as applicable: D395; D412;D471; D573; D638; D1434; D2240; D6869.11.1.1 The number of tests samples tested shall be consistent with the requirements of Section 9
48、.18.1 and 13.212.4.12. Inspection and Certification12.1 Inspection and certification of the material supplied with reference to a specification based on this classification systemshall be for conformance to the requirements specified herein.12.2 Lot-acceptance inspection shall be the basis on which
49、acceptance or rejection of the lot is made. The lot-acceptanceinspection shall consist of the tests listed as they apply: hardness; weight change in IRM 903 oil; moisture content; air permeability.12.3 Periodic-check inspection shall consist of the tests specified for all requirements of the material under this classificationsystem. Inspection frequency shall be adequate to ensure the material is certifiable in accordance with 13.412.4.12.4 Certification shall be that the material was manufactured by a process in statistical control, sampled, tested, and inspecte
