ASTM_F_1927_-_14.pdf

Designation:F192714Standard Test Method forDetermination of Oxygen Gas Transmission Rate,Permeability and Permeance at Controlled Relative HumidityThrough Barrier Materials Using a Coulometric Detector1This standard is issued under the fixed designation F1927;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.1.Scope1.1 This test method covers a procedure for determinationof the rate of transmission of oxygen gas,at steady-state,at agiven temperature and%RH level,through film,sheeting,laminates,co-extrusions,or plastic-coated papers or fabrics.This test method extends the common practice dealing withzero humidity or,at best,an assumed humidity.Humidity playsan important role in the oxygen gas transmission rate(O2GTR)of many materials.This test method provides for the determi-nation of oxygen gas transmission rate(O2GTR),the per-meance of the film to oxygen gas(PO2),the permeationcoefficient of the film to its thickness(P”O2),and oxygenpermeability coefficient(PO2)in the case of homogeneousmaterials at given temperature and%RH level(s).1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to address all of thesafety concerns,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.Specific precau-tionary statements are given in Section 9.2.Referenced Documents2.1 ASTM Standards:2D1898 Practice for Sampling of Plastics(Withdrawn 1998)3D3985 Test Method for Oxygen Gas Transmission RateThrough Plastic Film and Sheeting Using a CoulometricSensorE104 Practice for Maintaining Constant Relative Humidityby Means of Aqueous SolutionsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 oxygen permeability coeffcient(PO2)the product ofthe permeance and the thickness of the film.The permeabilityis meaningful only for homogeneous materials,in which caseit is a 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/(m s Pa).The test conditions(see 3.1.4)must bestated.3.1.2 oxygen permeance(PO2)the ratio of O2GTR to thedifference between the partial pressure of O2on the two sidesof the film.The SI unit of permeance is the mol/(m2 s Pa).The test conditions(see 3.1.4)must be stated.3.1.3 oxygen permeation coeffcient(P”O2)the ratio ofO2GTR to the thickness of the film.The SI unit of permeanceis the mol/(m2 s cm).The permeation coefficient is mean-ingful only for homogeneous materials,in which case it is aproperty characteristic of the bulk material.This quantityshould not be used unless the relationship between thicknessand transmission rate is known.3.1.4 oxygen transmission rateat a given temperature and%RH(O2GTR),the quantity of oxygen gas passing through aunit area of the parallel surfaces of a plastic film per unit timeunder the conditions of test.The SI unit of transmission rate isthe mol/(m2 s).The test conditions,including temperature,%RH and oxygen partial pressure on both sides of the filmmust be stated.3.1.5 transmission rate(O2GTR)a commonly used metricunit of O2GTR is the cm3(STP)/(m2 d)at one atmospherepressure differential where:1 cm3at Standard Temperature andPressure(STP=273.15K;1.013 105Pa)is 44.62 mol andone day is 86.4 103s.O2GTR in SI units is obtained by1This 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 April 1,2014.Published June 2014.Originallyapproved in 1998.Last previous edition approved in 2007 as F1927 07.DOI:10.1520/F1927-14.2For 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 multiplying the value in metric units by 5.165 10-10or thevalue in inch-pound units(cm3(STP)/100 in.2 d)by8.005 10-9.4.Summary of Test Method4.1 The oxygen gas transmission rate is determined after thesample has equilibrated in a given temperature and humidityenvironment.4.2 The specimen is mounted as a sealed semi-barrierbetween two chambers at ambient atmospheric pressure.Onechamber is slowly purged by a stream