ASTM_D_3985_-_05_2010e1.pdf

Designation:D398505(Reapproved 2010)1Standard Test Method forOxygen Gas Transmission Rate Through Plastic Film andSheeting Using a Coulometric Sensor1This standard is issued under the fixed designation D3985;the number immediately following the designation indicates the 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.1NOTEEditorial changes were made throughout in November 2010.1.Scope1.1 This test method covers a procedure for determinationof the steady-state rate of transmission of oxygen gas throughplastics in the form of film,sheeting,laminates,coextrusions,or plastic-coated papers or fabrics.It provides for the determi-nation of(1)oxygen gas transmission rate(OTR),(2)thepermeance of the film to oxygen gas(PO2),and(3)oxygenpermeability coefficient(PO2)in the case of homogeneousmaterials.1.2 This test method does not purport to be the only methodfor measurement of OTR.There may be other methods of OTRdetermination that use other oxygen sensors and procedures.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety problems,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1434 Test Method for Determining Gas Permeability Char-acteristics of Plastic Film and SheetingD1898 Practice for Sampling of Plastics(Withdrawn 1998)3E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF1927 Test Method for Determination of Oxygen Gas Trans-mission Rate,Permeability and Permeance at ControlledRelative Humidity Through Barrier Materials Using aCoulometric Detector3.Terminology3.1 Definitions:3.1.1 oxygen permeability coeffcient(PO2)the product ofthe permeance and the thickness of film.The permeability ismeaningful only for homogeneous materials,in which case it isa property characteristic of the bulk material.This quantityshould not be used,unless the relationship between thicknessand permeance has been verified on tests using several differentthicknesses of the material.The SI unit of oxygen permeabilityis the mol/(msPa).The test conditions(see 3.1.3)must bestated.3.1.2 oxygen permeance(PO2)the ratio of the OTR to thedifference between the partial pressure of O2on the two sidesof the film.The SI unit of permeance is the mol/(m2sPa).Thetest conditions(see 5.1)must be stated.3.1.3 oxygen transmission rate(OTR)the quantity ofoxygen gas passing through a unit area of the parallel surfacesof a plastic film per unit time under the conditions of test.TheSI unit of transmission rate is the mol/(m2s).The testconditions,including temperature and oxygen partial pressureon both sides of the film must be stated.3.1.3.1 A commonly used unit of OTR is the cm3(STP)/(m2d)at one atmosphere pressure difference where 1 cm3(STP)is 44.62 mol,1 atm is 0.1013 MPa,and one day is86.4 103s.The OTR in SI units is obtained by multiplying thevalue in inch-pound units by 5.160 10 10.4.Summary of Test Method4.1 The oxygen gas transmission rate is determined after thesample has equilibrated in a dry test environment.In thiscontext,a“dry”environment is considered to be one in whichthe relative humidity is less than 1%.4.2 The specimen is mounted as a sealed semi-barrierbetween two chambers at ambient atmospheric pressure.Onechamber is slowly purged by a stream of nitrogen and the otherchamber contains oxygen.As oxygen gas permeates through1This test method is under the jurisdiction ofASTM Committee F02 on FlexibleBarrier Packaging and is the direct responsibility of Subcommittee F02.10 onPermeation.Current edition approved Oct.1,2010.Published November 2010.Originallyapproved in 1981.Last previous edition approved in 2005 as D3985 051.DOI:10.1520/D3985-05R10E01.2For referenced ASTM standards,visit the ASTM website,www.astm.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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 the film into the nitrogen carrier gas,it is transported to thecoulometric detector where it produces an electrical current,the magnitude of which is proportional to the amount ofoxygen flowing into the detector per unit time.5.Significance and Use5.1 The OTR is an important determinant of the packagingprotection afforded by barrier materials.It is not,however,thesole determinant,and additional tests,based on experience,must be u