1、Designation:D444120Standard Specification forAqueous Dispersions of Polytetrafluoroethylene1This standard is issued under the fixed designation D4441;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number
2、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 aqueous dispersions of poly-tetrafluoroethylene(PTFE)resins.These resins are homopoly-mers of tetrafluoroethylene,or in
3、 some cases modified ho-mopolymers containing not more than 1%by weight of otherfluoromonomers.1.1.1 The dispersion is usually stabilized by one or moresurfactants.Other non-PTFE materials may be present in totalat 5%or less by weight for special purposes.1.1.2 This specification is for virgin mater
4、ial only and doesnot address recycled material as it is not appropriate fordispersions.1.2 This specification is used to determine if a shipment,lot,or container of PTFE dispersion is suitable for its intended use.It covers only aqueous dispersions of polytetrafluoroethylene.It does not cover PTFE c
5、opolymers or filled dispersions.Thisspecification includes test methods for both aqueous dispersionand the PTFE in the dispersion.NOTE1Uses for the PTFE dispersion covered by this specificationinclude,but are not limited to,casting of their films,impregnation ofmechanical packings and other material
6、s,surface coatings on varioussubstrates,combined impregnation and coating of fibrous materials,andco-coagulation with other materials for subsequent processing into films,sheets,rods,and tubes.NOTE2Information in this specification is technically equivalent torelated information in ISO 20568-1 and I
7、SO 20568-2.1.3 The values stated in SI units as detailed in IEEE/ASTMSI-10 are to be regarded as standard.The values given inparentheses are for information only.1.4 The following precautionary caveat pertains only to thetest method portions of this specification.This standard doesnot purport to add
8、ress all of the safety concerns,if any,associated with its use.It is the responsibility of the user of thisstandard to establish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.Specific precautionary information is given in Notes 5and 6.1.
9、5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Tr
10、ade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD3892 Practice for Packaging/Packing of PlasticsD4464 Test Method for Particle Size Distribution of Cata-lytic Materials by Laser Light ScatteringD4591 Test Method for Determining Temperatures andHeats o
11、f Transitions of Fluoropolymers by DifferentialScanning CalorimetryD4894 Specification for Polytetrafluoroethylene(PTFE)Granular Molding and Ram Extrusion Materials3D4895 Specification for Polytetrafluoroethylene(PTFE)Resin Produced From Dispersion3E70 Test Method for pH of Aqueous Solutions With th
12、eGlass ElectrodeIEEE/ASTM SI-10 Use of the International System of Units(SI):The Modern Metric System2.2 ISO Standards:4ISO 20568-1 PlasticsFluoropolymer Dispersions andMolding and Extrusion MaterialsPart 1:Designationand SpecificationISO 20568-2 PlasticsFluoropolymer Dispersions andMolding and Extr
13、usion MaterialsPart 2:Preparation ofTest Specimens and Determination of Properties3.Terminology3.1 Definitions:3.1.1 GeneralThe terminology given in TerminologyD883 is applicable to this specification.1This specification is under the jurisdiction of ASTM Committee D20 onPlastics and is the direct re
14、sponsibility of Subcommittee D20.15 on ThermoplasticMaterials(Section D20.15.12).Current edition approved July 1,2020.Published July 2020.Originally approvedin 1984.Last previous edition approved in 2015 as D4441-15.DOI:10.1520/D4441-20.2For referenced ASTM standards,visit the ASTM website,www.astm.
15、org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Specifications for other forms of polytetrafluoroethylene may be found inSpecifications D4894 and D4895.4Available from American
16、 National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendatio
